[Diagnostic performance of biliary ultrasound vs. magnetic resonance cholangiogram in patients with recurrent biliary obstruction.].

PubMed

Chávez-Valencia, V; Espinosa-Ortega, H F; Espinoza-Peralta, D; Arce-Salinas, C A

2009-01-01

Obstructive jaundice in patients with previous cholecystectomy requires a precise diagnosis. In the diagnostic algorithm, biliary ultrasound (BUS) and magnetic resonance cholangiogram (MRC) are used, although the accuracy of each method is unknown in our setting. No previous comparison of US and MRC in subjects with cholecystectomy has been made. To determine diagnostic accuracy of BUS and MRC in patients with recurrent biliary obstruction. Patients with endoscopic retrograde cholangiopacreatography (ERCP) demonstrating recurrent biliary obstruction by stones were included. All patients underwent BUS and MRC. We determined the diagnostic performance of each image study compared with ERCP. Twenty-seven patients with a mean age of 62.9 +/- 17.3 years-old were included. Sensitivity and specificity of BUS were 0.12 and 0.58, respectively. Figures for MRC were 0.88 and 0.82. Diagnostic agreement between ERCP and MRC was k= 0.66 whereas BUS had a k of only 0.26. MRC had good diagnostic performance for recurrent choledocolithiasis. BUS demonstrated lower accuracy compared with previous reports, so should not be considered in the initial approach of recurrent choledocus obstruction.

Indexing of diagnosis accuracy studies in MEDLINE and EMBASE.

PubMed

Wilczynski, Nancy L; Haynes, R Brian

2007-10-11

STAndards for Reporting of Diagnostic Accuracy (STARD) were published in 2003 and endorsed by some journals but not others. To determine whether the quality of indexing of diagnostic accuracy studies in MEDLINE and EMBASE has improved since the STARD statement was published. Evaluate the change in the mean number of "accurate index terms" assigned to diagnostic accuracy studies, comparing STARD (endorsing) and non-STARD (non-endorsing) journals, for 2 years before and after STARD publication. In MEDLINE, no differences in indexing quality were found for STARD and non-STARD journals before or after the STARD statement was published in 2003. In EMBASE, indexing in STARD journals improved compared with non-STARD journals (p = 0.02). However, articles in STARD journals had half the number of accurate indexing terms as articles in non-STARD journals, both before and after STARD statement publication (p < 0.001).

ROC curves in clinical chemistry: uses, misuses, and possible solutions.

PubMed

Obuchowski, Nancy A; Lieber, Michael L; Wians, Frank H

2004-07-01

ROC curves have become the standard for describing and comparing the accuracy of diagnostic tests. Not surprisingly, ROC curves are used often by clinical chemists. Our aims were to observe how the accuracy of clinical laboratory diagnostic tests is assessed, compared, and reported in the literature; to identify common problems with the use of ROC curves; and to offer some possible solutions. We reviewed every original work using ROC curves and published in Clinical Chemistry in 2001 or 2002. For each article we recorded phase of the research, prospective or retrospective design, sample size, presence/absence of confidence intervals (CIs), nature of the statistical analysis, and major analysis problems. Of 58 articles, 31% were phase I (exploratory), 50% were phase II (challenge), and 19% were phase III (advanced) studies. The studies increased in sample size from phase I to III and showed a progression in the use of prospective designs. Most phase I studies were powered to assess diagnostic tests with ROC areas >/=0.70. Thirty-eight percent of studies failed to include CIs for diagnostic test accuracy or the CIs were constructed inappropriately. Thirty-three percent of studies provided insufficient analysis for comparing diagnostic tests. Other problems included dichotomization of the gold standard scale and inappropriate analysis of the equivalence of two diagnostic tests. We identify available software and make some suggestions for sample size determination, testing for equivalence in diagnostic accuracy, and alternatives to a dichotomous classification of a continuous-scale gold standard. More methodologic research is needed in areas specific to clinical chemistry.

Regression Analysis of Optical Coherence Tomography Disc Variables for Glaucoma Diagnosis.

PubMed

Richter, Grace M; Zhang, Xinbo; Tan, Ou; Francis, Brian A; Chopra, Vikas; Greenfield, David S; Varma, Rohit; Schuman, Joel S; Huang, David

2016-08-01

To report diagnostic accuracy of optical coherence tomography (OCT) disc variables using both time-domain (TD) and Fourier-domain (FD) OCT, and to improve the use of OCT disc variable measurements for glaucoma diagnosis through regression analyses that adjust for optic disc size and axial length-based magnification error. Observational, cross-sectional. In total, 180 normal eyes of 112 participants and 180 eyes of 138 participants with perimetric glaucoma from the Advanced Imaging for Glaucoma Study. Diagnostic variables evaluated from TD-OCT and FD-OCT were: disc area, rim area, rim volume, optic nerve head volume, vertical cup-to-disc ratio (CDR), and horizontal CDR. These were compared with overall retinal nerve fiber layer thickness and ganglion cell complex. Regression analyses were performed that corrected for optic disc size and axial length. Area-under-receiver-operating curves (AUROC) were used to assess diagnostic accuracy before and after the adjustments. An index based on multiple logistic regression that combined optic disc variables with axial length was also explored with the aim of improving diagnostic accuracy of disc variables. Comparison of diagnostic accuracy of disc variables, as measured by AUROC. The unadjusted disc variables with the highest diagnostic accuracies were: rim volume for TD-OCT (AUROC=0.864) and vertical CDR (AUROC=0.874) for FD-OCT. Magnification correction significantly worsened diagnostic accuracy for rim variables, and while optic disc size adjustments partially restored diagnostic accuracy, the adjusted AUROCs were still lower. Axial length adjustments to disc variables in the form of multiple logistic regression indices led to a slight but insignificant improvement in diagnostic accuracy. Our various regression approaches were not able to significantly improve disc-based OCT glaucoma diagnosis. However, disc rim area and vertical CDR had very high diagnostic accuracy, and these disc variables can serve to complement additional OCT measurements for diagnosis of glaucoma.

Diagnostic accuracy of transabdominal high-resolution US for staging gallbladder cancer and differential diagnosis of neoplastic polyps compared with EUS.

PubMed

Lee, Jeong Sub; Kim, Jung Hoon; Kim, Yong Jae; Ryu, Ji Kon; Kim, Yong-Tae; Lee, Jae Young; Han, Joon Koo

2017-07-01

To compare the diagnostic accuracy of transabdominal high-resolution ultrasound (HRUS) for staging gallbladder cancer and differential diagnosis of neoplastic polyps compared with endoscopic ultrasound (EUS) and pathology. Among 125 patients who underwent both HRUS and EUS, we included 29 pathologically proven cancers (T1 = 7, T2 = 19, T3 = 3) including 15 polypoid cancers and 50 surgically proven polyps (neoplastic = 30, non-neoplastic = 20). We reviewed formal reports and assessed the accuracy of HRUS and EUS for diagnosing cancer as well as the differential diagnosis of neoplastic polyps. Statistical analyses were performed using chi-square tests. The sensitivity, specificity, PPV, and NPV for gallbladder cancer were 82.7 %, 44.4 %, 82.7 %, and 44 % using HRUS and 86.2 %, 22.2 %, 78.1 %, and 33.3 % using EUS. HRUS and EUS correctly diagnosed the stage in 13 and 12 patients. The sensitivity, specificity, PPV, and NPV for neoplastic polyps were 80 %, 80 %, 86 %, and 73 % using HRUS and 73 %, 85 %, 88 %, and 69 % using EUS. Single polyps (8/20 vs. 21/30), larger (1.0 ± 0.28 cm vs. 1.9 ± 0.85 cm) polyps, and older age (52.5 ± 13.2 vs. 66.1 ± 10.3 years) were common in neoplastic polyps (p < 0.05). Transabdominal HRUS showed comparable accuracy for diagnosing gallbladder cancer and differentiating neoplastic polyps compared with EUS. HRUS is also easy to use during our routine ultrasound examinations. • HRUS showed comparable diagnostic accuracy for GB cancer compared with EUS. • HRUS and EUS showed similar diagnostic accuracy for differentiating neoplastic polyps. • Single, larger polyps and older age were common in neoplastic polyps. • HRUS is less invasive compared with EUS.

[Diagnostic value of cardiac magnetic resonance in patients with acute viral myocarditis].

PubMed

Ouyang, Haichun; Chen, Haixiong; Hu, Yunzhao; Wu, Yanxian; Li, Wensheng; Chen, Yuying; Cen, Yujian

2014-11-01

To assess the diagnostic value of cardiac magnetic resonance (CMR) in patients with acute viral myocarditis. Thirty patients with suspected acute viral myocarditis admitted in first people's hospital of Shunde from June 2011 to June 2013 were included in this prospective study. The diagnostic sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and accuracy of acute viral myocarditis were evaluated by clinical diagnosis. Diagnostic value among different scan methods and Lake Louise criteria were compared. Acute viral myocarditis was diagnosed in 63.33% (19/30) patients.Values for sensitivity, specificity, PPV, NPV, and diagnostic accuracy within the overall cohort were 57.89%, 72.73%, 78.57%, 50.00%, 63.33%, respectively by edema imaging (ER).Values for sensitivity, specificity, PPV, NPV, and diagnostic accuracy within the overall cohort were 78.95%, 63.64%, 78.95%, 63.64%, 73.33%, respectively using global relative enhancement (gRE).Values for sensitivity, specificity, PPV, NPV, and diagnostic accuracy within the overall cohort were 78.95%, 54.55%, 75.00%, 60.00%, 70.00%, respectively using late gadolinium enhancement (LGE) criteria.Values for sensitivity, specificity, PPV, NPV, and diagnostic accuracy within the overall cohort were 84.21%, 81.82%, 88.89%, 75.00%, 83.33% using Lake Louise criteria. The sensitivity, specificity, PPV, NPV, and diagnostic accuracy using Lake Louise criteria were significantly higher than using ER, gRE, LGE alone(all P < 0.05).Specificity was higher using ER than using gRE and LGE (both P < 0.05). The sensitivity, NPV, and diagnostic accuracy were significantly higher using gRE than using ER (all P < 0.05) and was similar as using LGE (all P > 0.05). Cardiac magnetic resonance is an excellent imaging modality for the diagnosis of acute viral myocarditis.

A Prospective, Blinded, Multicenter Clinical Trial to Compare the Efficacy, Accuracy, and Safety of In-Office Diagnostic Arthroscopy With Magnetic Resonance Imaging and Surgical Diagnostic Arthroscopy.

PubMed

Gill, Thomas J; Safran, Marc; Mandelbaum, Bert; Huber, Bryan; Gambardella, Ralph; Xerogeanes, John

2018-05-24

The purpose of this study was to compare the efficacy, accuracy, and safety of in-office diagnostic arthroscopy with magnetic resonance imaging (MRI) and surgical diagnostic arthroscopy. A prospective, blinded, multicenter, clinical trial was performed on 110 patients, ages 18 to 75 years, who presented with knee pain. The study period was April 2012 to April 2013. Each patient underwent a physical examination, an MRI, in-office diagnostic imaging, and a diagnostic arthroscopic examination in the operating room. The attending physician completed clinical report forms comparing the in-office arthroscopic examination and surgical diagnostic arthroscopy findings on each patient. Two blinded experts, unaffiliated with the clinical care of the study's subjects, reviewed the in-office arthroscopic images and MRI images using the surgical diagnostic arthroscopy images as the "control" group comparison. Patients were consecutive, and no patients were excluded from the study. In this study, the accuracy, sensitivity, and specificity of in-office arthroscopy was equivalent to surgical diagnostic arthroscopy and more accurate than MRI. When comparing in-office arthroscopy with surgical diagnostic arthroscopy, all kappa statistics were between 0.766 and 0.902. For MRI compared with surgical diagnostic arthroscopy, kappa values ranged from a low of 0.130 (considered "slight" agreement) to a high of 0.535 (considered "moderate" agreement). The comparison of MRI to in-office arthroscopy showed very similar results as the comparison of MRI with surgical diagnostic arthroscopy, ranging from a low kappa of 0.112 (slight agreement) to a high of 0.546 (moderate agreement). There were no patient-related or device-related complications related to the use of in-office arthroscopy. Needle-based diagnostic imaging that can be used in the office setting is statistically equivalent to surgical diagnostic arthroscopy with regard to the diagnosis of intra-articular, nonligamentous knee joint pathology. In-office diagnostic imaging can provide a more detailed and accurate diagnostic assessment of intra-articular knee pathology than MRI. Based on the study results, in-office diagnostic imaging provides a safe, accurate, real-time, minimally invasive diagnostic modality to evaluate intra-articular pathology without the need for surgical diagnostic arthroscopy or high-cost imaging. Level II, comparative prospective trial. Copyright © 2018 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.

Bayesian modeling and inference for diagnostic accuracy and probability of disease based on multiple diagnostic biomarkers with and without a perfect reference standard.

PubMed

Jafarzadeh, S Reza; Johnson, Wesley O; Gardner, Ian A

2016-03-15

The area under the receiver operating characteristic (ROC) curve (AUC) is used as a performance metric for quantitative tests. Although multiple biomarkers may be available for diagnostic or screening purposes, diagnostic accuracy is often assessed individually rather than in combination. In this paper, we consider the interesting problem of combining multiple biomarkers for use in a single diagnostic criterion with the goal of improving the diagnostic accuracy above that of an individual biomarker. The diagnostic criterion created from multiple biomarkers is based on the predictive probability of disease, conditional on given multiple biomarker outcomes. If the computed predictive probability exceeds a specified cutoff, the corresponding subject is allocated as 'diseased'. This defines a standard diagnostic criterion that has its own ROC curve, namely, the combined ROC (cROC). The AUC metric for cROC, namely, the combined AUC (cAUC), is used to compare the predictive criterion based on multiple biomarkers to one based on fewer biomarkers. A multivariate random-effects model is proposed for modeling multiple normally distributed dependent scores. Bayesian methods for estimating ROC curves and corresponding (marginal) AUCs are developed when a perfect reference standard is not available. In addition, cAUCs are computed to compare the accuracy of different combinations of biomarkers for diagnosis. The methods are evaluated using simulations and are applied to data for Johne's disease (paratuberculosis) in cattle. Copyright © 2015 John Wiley & Sons, Ltd.

Transbronchial Lung Cryobiopsy and Video-assisted Thoracoscopic Lung Biopsy in the Diagnosis of Diffuse Parenchymal Lung Disease. A Meta-analysis of Diagnostic Test Accuracy.

PubMed

Iftikhar, Imran H; Alghothani, Lana; Sardi, Alejandro; Berkowitz, David; Musani, Ali I

2017-07-01

Transbronchial lung cryobiopsy is increasingly being used for the assessment of diffuse parenchymal lung diseases. Several studies have shown larger biopsy samples and higher yields compared with conventional transbronchial biopsies. However, the higher risk of bleeding and other complications has raised concerns for widespread use of this modality. To study the diagnostic accuracy and safety profile of transbronchial lung cryobiopsy and compare with video-assisted thoracoscopic surgery (VATS) by reviewing available evidence from the literature. Medline and PubMed were searched from inception until December 2016. Data on diagnostic performance were abstracted by constructing two-by-two contingency tables for each study. Data on a priori selected safety outcomes were collected. Risk of bias was assessed with the Quality Assessment of Diagnostic Accuracy Studies tool. Random effects meta-analyses were performed to obtain summary estimates of the diagnostic accuracy. The pooled diagnostic yield, pooled sensitivity, and pooled specificity of transbronchial lung cryobiopsy were 83.7% (76.9-88.8%), 87% (85-89%), and 57% (40-73%), respectively. The pooled diagnostic yield, pooled sensitivity, and pooled specificity of VATS were 92.7% (87.6-95.8%), 91.0% (89-92%), and 58% (31-81%), respectively. The incidence of grade 2 (moderate to severe) endobronchial bleeding after transbronchial lung cryobiopsy and of post-procedural pneumothorax was 4.9% (2.2-10.7%) and 9.5% (5.9-14.9%), respectively. Although the diagnostic test accuracy measures of transbronchial lung cryobiopsy lag behind those of VATS, with an acceptable safety profile and potential cost savings, the former could be considered as an alternative in the evaluation of patients with diffuse parenchymal lung diseases.

Performance of search strategies to retrieve systematic reviews of diagnostic test accuracy from the Cochrane Library.

PubMed

Huang, Yuansheng; Yang, Zhirong; Wang, Jing; Zhuo, Lin; Li, Zhixia; Zhan, Siyan

2016-05-06

To compare the performance of search strategies to retrieve systematic reviews of diagnostic test accuracy from The Cochrane Library. Databases of CDSR and DARE in the Cochrane Library were searched for systematic reviews of diagnostic test accuracy published between 2008 and 2012 through nine search strategies. Each strategy consists of one group or combination of groups of searching filters about diagnostic test accuracy. Four groups of diagnostic filters were used. The Strategy combing all the filters was used as the reference to determine the sensitivity, precision, and the sensitivity x precision product for another eight Strategies. The reference Strategy retrieved 8029 records, of which 832 were eligible. The strategy only composed of MeSH terms about "accuracy measures" achieved the highest values in both precision (69.71%) and product (52.45%) with a moderate sensitivity (75.24%). The combination of MeSH terms and free text words about "accuracy measures" contributed little to increasing the sensitivity. Strategies composed of filters about "diagnosis" had similar sensitivity but lower precision and product to those composed of filters about "accuracy measures". MeSH term "exp'diagnosis' " achieved the lowest precision (9.78%) and product (7.91%), while its hyponym retrieved only half the number of records at the expense of missing 53 target articles. The precision was negatively correlated with sensitivities among the nine strategies. Compared to the filters about "diagnosis", the filters about "accuracy measures" achieved similar sensitivities but higher precision. When combining both terms, sensitivity of the strategy was enhanced obviously. The combination of MeSH terms and free text words about the same concept seemed to be meaningless for enhancing sensitivity. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Diagnostic accuracy of serological diagnosis of hepatitis C and B using dried blood spot samples (DBS): two systematic reviews and meta-analyses.

PubMed

Lange, Berit; Cohn, Jennifer; Roberts, Teri; Camp, Johannes; Chauffour, Jeanne; Gummadi, Nina; Ishizaki, Azumi; Nagarathnam, Anupriya; Tuaillon, Edouard; van de Perre, Philippe; Pichler, Christine; Easterbrook, Philippa; Denkinger, Claudia M

2017-11-01

Dried blood spots (DBS) are a convenient tool to enable diagnostic testing for viral diseases due to transport, handling and logistical advantages over conventional venous blood sampling. A better understanding of the performance of serological testing for hepatitis C (HCV) and hepatitis B virus (HBV) from DBS is important to enable more widespread use of this sampling approach in resource limited settings, and to inform the 2017 World Health Organization (WHO) guidance on testing for HBV/HCV. We conducted two systematic reviews and meta-analyses on the diagnostic accuracy of HCV antibody (HCV-Ab) and HBV surface antigen (HBsAg) from DBS samples compared to venous blood samples. MEDLINE, EMBASE, Global Health and Cochrane library were searched for studies that assessed diagnostic accuracy with DBS and agreement between DBS and venous sampling. Heterogeneity of results was assessed and where possible a pooled analysis of sensitivity and specificity was performed using a bivariate analysis with maximum likelihood estimate and 95% confidence intervals (95%CI). We conducted a narrative review on the impact of varying storage conditions or limits of detection in subsets of samples. The QUADAS-2 tool was used to assess risk of bias. For the diagnostic accuracy of HBsAg from DBS compared to venous blood, 19 studies were included in a quantitative meta-analysis, and 23 in a narrative review. Pooled sensitivity and specificity were 98% (95%CI:95%-99%) and 100% (95%CI:99-100%), respectively. For the diagnostic accuracy of HCV-Ab from DBS, 19 studies were included in a pooled quantitative meta-analysis, and 23 studies were included in a narrative review. Pooled estimates of sensitivity and specificity were 98% (CI95%:95-99) and 99% (CI95%:98-100), respectively. Overall quality of studies and heterogeneity were rated as moderate in both systematic reviews. HCV-Ab and HBsAg testing using DBS compared to venous blood sampling was associated with excellent diagnostic accuracy. However, generalizability is limited as no uniform protocol was applied and most studies did not use fresh samples. Future studies on diagnostic accuracy should include an assessment of impact of environmental conditions common in low resource field settings. Manufacturers also need to formally validate their assays for DBS for use with their commercial assays.

Stationary intraoral tomosynthesis for dental imaging

NASA Astrophysics Data System (ADS)

Inscoe, Christina R.; Wu, Gongting; Soulioti, Danai E.; Platin, Enrique; Mol, Andre; Gaalaas, Laurence R.; Anderson, Michael R.; Tucker, Andrew W.; Boyce, Sarah; Shan, Jing; Gonzales, Brian; Lu, Jianping; Zhou, Otto

2017-03-01

Despite recent advances in dental radiography, the diagnostic accuracies for some of the most common dental diseases have not improved significantly, and in some cases remain low. Intraoral x-ray is the most commonly used x-ray diagnostic tool in dental clinics. It however suffers from the typical limitations of a 2D imaging modality including structure overlap. Cone-beam computed tomography (CBCT) uses high radiation dose and suffers from image artifacts and relatively low resolution. The purpose of this study is to investigate the feasibility of developing a stationary intraoral tomosynthesis (s-IOT) using spatially distributed carbon nanotube (CNT) x-ray array technology, and to evaluate its diagnostic accuracy compared to conventional 2D intraoral x-ray. A bench-top s-IOT device was constructed using a linear CNT based X-ray source array and a digital intraoral detector. Image reconstruction was performed using an iterative reconstruction algorithm. Studies were performed to optimize the imaging configuration. For evaluation of s-IOT's diagnostic accuracy, images of a dental quality assurance phantom, and extracted human tooth specimens were acquired. Results show s-IOT increases the diagnostic sensitivity for caries compared to intraoral x-ray at a comparable dose level.

A structured proteomic approach identifies 14-3-3Sigma as a novel and reliable protein biomarker in panel based differential diagnostics of liver tumors.

PubMed

Reis, Henning; Pütter, Carolin; Megger, Dominik A; Bracht, Thilo; Weber, Frank; Hoffmann, Andreas-C; Bertram, Stefanie; Wohlschläger, Jeremias; Hagemann, Sascha; Eisenacher, Martin; Scherag, André; Schlaak, Jörg F; Canbay, Ali; Meyer, Helmut E; Sitek, Barbara; Baba, Hideo A

2015-06-01

Hepatocellular carcinoma (HCC) is a major lethal cancer worldwide. Despite sophisticated diagnostic algorithms, the differential diagnosis of small liver nodules still is difficult. While imaging techniques have advanced, adjuvant protein-biomarkers as glypican3 (GPC3), glutamine-synthetase (GS) and heat-shock protein 70 (HSP70) have enhanced diagnostic accuracy. The aim was to further detect useful protein-biomarkers of HCC with a structured systematic approach using differential proteome techniques, bring the results to practical application and compare the diagnostic accuracy of the candidates with the established biomarkers. After label-free and gel-based proteomics (n=18 HCC/corresponding non-tumorous liver tissue (NTLT)) biomarker candidates were tested for diagnostic accuracy in immunohistochemical analyses (n=14 HCC/NTLT). Suitable candidates were further tested for consistency in comparison to known protein-biomarkers in HCC (n=78), hepatocellular adenoma (n=25; HCA), focal nodular hyperplasia (n=28; FNH) and cirrhosis (n=28). Of all protein-biomarkers, 14-3-3Sigma (14-3-3S) exhibited the most pronounced up-regulation (58.8×) in proteomics and superior diagnostic accuracy (73.0%) in the differentiation of HCC from non-tumorous hepatocytes also compared to established biomarkers as GPC3 (64.7%) and GS (45.4%). 14-3-3S was part of the best diagnostic three-biomarker panel (GPC3, HSP70, 14-3-3S) for the differentiation of HCC and HCA which is of most important significance. Exclusion of GS and inclusion of 14-3-3S in the panel (>1 marker positive) resulted in a profound increase in specificity (+44.0%) and accuracy (+11.0%) while sensitivity remained stable (96.0%). 14-3-3S is an interesting protein biomarker with the potential to further improve the accuracy of differential diagnostic process of hepatocellular tumors. This article is part of a Special Issue entitled: Medical Proteomics. Copyright © 2014 Elsevier B.V. All rights reserved.

Receiver operating characteristic (ROC) curves: review of methods with applications in diagnostic medicine

NASA Astrophysics Data System (ADS)

Obuchowski, Nancy A.; Bullen, Jennifer A.

2018-04-01

Receiver operating characteristic (ROC) analysis is a tool used to describe the discrimination accuracy of a diagnostic test or prediction model. While sensitivity and specificity are the basic metrics of accuracy, they have many limitations when characterizing test accuracy, particularly when comparing the accuracies of competing tests. In this article we review the basic study design features of ROC studies, illustrate sample size calculations, present statistical methods for measuring and comparing accuracy, and highlight commonly used ROC software. We include descriptions of multi-reader ROC study design and analysis, address frequently seen problems of verification and location bias, discuss clustered data, and provide strategies for testing endpoints in ROC studies. The methods are illustrated with a study of transmission ultrasound for diagnosing breast lesions.

Diagnostic accuracy of 3D-transvaginal ultrasound in detecting uterine cavity abnormalities in infertile patients as compared with hysteroscopy.

PubMed

Apirakviriya, Chayanis; Rungruxsirivorn, Tassawan; Phupong, Vorapong; Wisawasukmongchol, Wirach

2016-05-01

To assess diagnostic accuracy of 3D transvaginal ultrasound (3D-TVS) compared with hysteroscopy in detecting uterine cavity abnormalities in infertile women. This prospective observational cross-sectional study was conducted during the July 2013 to December 2013 study period. Sixty-nine women with infertility were enrolled. In the mid to late follicular phase of each subject's menstrual cycle, 3D transvaginal ultrasound and hysteroscopy were performed on the same day in each patient. Hysteroscopy is widely considered to be the gold standard method for investigation of the uterine cavity. Uterine cavity characteristics and abnormalities were recorded. Diagnostic accuracy, sensitivity, specificity, positive predictive value, negative predictive value, and positive and negative likelihood ratios were evaluated. Hysteroscopy was successfully performed in all subjects. Hysteroscopy diagnosed pathological findings in 22 of 69 cases (31.8%). There were 18 endometrial polyps, 3 submucous myomas, and 1 septate uterus. Three-dimensional transvaginal ultrasound in comparison with hysteroscopy had 84.1% diagnostic accuracy, 68.2% sensitivity, 91.5% specificity, 79% positive predictive value, and 86% negative predictive value. The positive and negative likelihood ratios were 8.01 and 0.3, respectively. 3D-TVS successfully detected every case of submucous myoma and uterine anomaly. For detection of endometrial polyps, 3D-TVS had 61.1% sensitivity, 91.5% specificity, and 83.1% diagnostic accuracy. 3D-TVS demonstrated 84.1% diagnostic accuracy for detecting uterine cavity abnormalities in infertile women. A significant percentage of infertile patients had evidence of uterine cavity pathology. Hysteroscopy is, therefore, recommended for accurate detection and diagnosis of uterine cavity lesion. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Evaluation of diagnostic accuracy in detecting ordered symptom statuses without a gold standard

PubMed Central

Wang, Zheyu; Zhou, Xiao-Hua; Wang, Miqu

2011-01-01

Our research is motivated by 2 methodological problems in assessing diagnostic accuracy of traditional Chinese medicine (TCM) doctors in detecting a particular symptom whose true status has an ordinal scale and is unknown—imperfect gold standard bias and ordinal scale symptom status. In this paper, we proposed a nonparametric maximum likelihood method for estimating and comparing the accuracy of different doctors in detecting a particular symptom without a gold standard when the true symptom status had an ordered multiple class. In addition, we extended the concept of the area under the receiver operating characteristic curve to a hyper-dimensional overall accuracy for diagnostic accuracy and alternative graphs for displaying a visual result. The simulation studies showed that the proposed method had good performance in terms of bias and mean squared error. Finally, we applied our method to our motivating example on assessing the diagnostic abilities of 5 TCM doctors in detecting symptoms related to Chills disease. PMID:21209155

Comparison of Diagnostic Accuracy of Clinical Measures of Breast Cancer–Related Lymphedema: Area Under the Curve

PubMed Central

Smoot, Betty J.; Wong, Josephine F.; Dodd, Marylin J.

2013-01-01

Objective To compare diagnostic accuracy of measures of breast cancer–related lymphedema (BCRL). Design Cross-sectional design comparing clinical measures with the criterion standard of previous diagnosis of BCRL. Setting University of California San Francisco Translational Science Clinical Research Center. Participants Women older than 18 years and more than 6 months posttreatment for breast cancer (n=141; 70 with BCRL, 71 without BCRL). Interventions Not applicable. Main Outcome Measures Sensitivity, specificity, receiver operator characteristic curve, and area under the curve (AUC) were used to evaluate accuracy. Results A total of 141 women were categorized as having (n=70) or not having (n=71) BCRL based on past diagnosis by a health care provider, which was used as the reference standard. Analyses of ROC curves for the continuous outcomes yielded AUC of .68 to .88 (P<.001); of the physical measures bioimpedance spectroscopy yielded the highest accuracy with an AUC of .88 (95% confidence interval, .80–.96) for women whose dominant arm was the affected arm. The lowest accuracy was found using the 2-cm diagnostic cutoff score to identify previously diagnosed BCRL (AUC, .54–.65). Conclusions Our findings support the use of bioimpedance spectroscopy in the assessment of existing BCRL. Refining diagnostic cutoff values may improve accuracy of diagnosis and warrant further investigation. PMID:21440706

Diagnostic test accuracy of nutritional tools used to identify undernutrition in patients with colorectal cancer: a systematic review.

PubMed

Håkonsen, Sasja Jul; Pedersen, Preben Ulrich; Bath-Hextall, Fiona; Kirkpatrick, Pamela

2015-05-15

Effective nutritional screening, nutritional care planning and nutritional support are essential in all settings, and there is no doubt that a health service seeking to increase safety and clinical effectiveness must take nutritional care seriously. Screening and early detection of malnutrition is crucial in identifying patients at nutritional risk. There is a high prevalence of malnutrition in hospitalized patients undergoing treatment for colorectal cancer. To synthesize the best available evidence regarding the diagnostic test accuracy of nutritional tools (sensitivity and specificity) used to identify malnutrition (specifically undernutrition) in patients with colorectal cancer (such as the Malnutrition Screening Tool and Nutritional Risk Index) compared to reference tests (such as the Subjective Global Assessment or Patient Generated Subjective Global Assessment). Patients with colorectal cancer requiring either (or all) surgery, chemotherapy and/or radiotherapy in secondary care. Focus of the review: The diagnostic test accuracy of validated assessment tools/instruments (such as the Malnutrition Screening Tool and Nutritional Risk Index) in the diagnosis of malnutrition (specifically under-nutrition) in patients with colorectal cancer, relative to reference tests (Subjective Global Assessment or Patient Generated Subjective Global Assessment). Types of studies: Diagnostic test accuracy studies regardless of study design. Studies published in English, German, Danish, Swedish and Norwegian were considered for inclusion in this review. Databases were searched from their inception to April 2014. Methodological quality was determined using the Quality Assessment of Diagnostic Accuracy Studies checklist. Data was collected using the data extraction form: the Standards for Reporting Studies of Diagnostic Accuracy checklist for the reporting of studies of diagnostic accuracy. The accuracy of diagnostic tests is presented in terms of sensitivity, specificity, positive and negative predictive values. In addition, the positive likelihood ratio (sensitivity/ [1 - specificity]) and negative likelihood ratio (1 - sensitivity)/ specificity), were also calculated and presented in this review to provide information about the likelihood that a given test result would be expected when the target condition is present compared with the likelihood that the same result would be expected when the condition is absent. Not all trials reported true positive, true negative, false positive and false negative rates, therefore these rates were calculated based on the data in the published papers. A two-by-two truth table was reconstructed for each study, and sensitivity, specificity, positive predictive value, negative predictive value positive likelihood ratio and negative likelihood ratio were calculated for each study. A summary receiver operator characteristics curve was constructed to determine the relationship between sensitivity and specificity, and the area under the summary receiver operator characteristics curve which measured the usefulness of a test was calculated. Meta-analysis was not considered appropriate, therefore data was synthesized in a narrative summary. 1. One study evaluated the Malnutrition Screening Tool against the reference standard Patient-Generated Subjective Global Assessment. The sensitivity was 56% and the specificity 84%. The positive likelihood ratio was 3.100, negative likelihood ratio was 0.59, the diagnostic odds ratio (CI 95%) was 5.20 (1.09-24.90) and the Area Under the Curve (AUC) represents only a poor to fair diagnostic test accuracy. A total of two studies evaluated the diagnostic accuracy of Malnutrition Universal Screening Tool (MUST) (index test) compared to both Subjective Global Assessment (SGA) (reference standard) and PG-SGA (reference standard) in patients with colorectal cancer. In MUST vs SGA the sensitivity of the tool was 96%, specificity was 75%, LR+ 3.826, LR- 0.058, diagnostic OR (CI 95%) 66.00 (6.61-659.24) and AUC represented excellent diagnostic accuracy. In MUST vs PG-SGA the sensitivity of the tool was 72%, specificity 48.9%, LR+ 1.382, LR- 0.579, diagnostic OR (CI 95%) 2.39 (0.87-6.58) and AUC indicated that the tool failed as a diagnostic test to identify patients with colorectal cancer at nutritional risk,. The Nutrition Risk Index (NRI) was compared to SGA representing a sensitivity of 95.2%, specificity of 62.5%, LR+ 2.521, LR- 0.087, diagnostic OR (CI 95%) 28.89 (6.93-120.40) and AUC represented good diagnostic accuracy. In regard to NRI vs PG-SGA the sensitivity of the tool was 68%, specificity 64%, LR+ 1.947, LR- 0.487, diagnostic OR (CI 95%) 4.00 (1.23-13.01) and AUC indicated poor diagnostic test accuracy. There are no single, specific tools used to screen or assess the nutritional status of colorectal cancer patients. All tools showed varied diagnostic accuracies when compared to the reference standards SGA and PG-SGA. Hence clinical judgment combined with perhaps the SGA or PG-SGA should play a major role. The PG-SGA offers several advantages over the SGA tool: 1) the patient completes the medical history component, thereby decreasing the amount of time involved; 2) it contains more nutrition impact symptoms, which are important to the patient with cancer; and 3) it has a scoring system that allows patients to be triaged for nutritional intervention. Therefore, the PG-SGA could be used as a nutrition assessment tool as it allows quick identification and prioritization of colorectal cancer patients with malnutrition in combination with other parameters. This systematic review highlights the need for the following: Further studies needs to investigate the diagnostic accuracy of already existing nutritional screening tools in the context of colorectal cancer patients. If new screenings tools are developed, they should be developed and validated in the specific clinical context within the same patient population (colorectal cancer patients). The Joanna Briggs Institute.

Accuracy of radiographic caries diagnosis using different X-ray generators.

PubMed

Svenson, B; Petersson, A

1989-05-01

Dental X-ray machines utilizing five different combinations of X-ray generators and tube voltages (Philips Oralix 65 kV, Siemens Heliodent EC 60 kV, Siemens Heliodent 70 kV, Soredex Minray DC 60 kV and Soredex Minray DC 70 kV) were compared with respect to the accuracy of radiographic diagnosis of proximal caries. Nine observers diagnosed proximal caries in radiographs of extracted premolars. The findings of the observers were compared to the actual presence or absence of caries. The ROC-curve technique was used to evaluate differences in diagnostic accuracy between the X-ray machines. The results showed small differences in diagnostic accuracy between the different X-ray generators but they proved to be statistically non-significant.

Efficient strategies to find diagnostic test accuracy studies in kidney journals.

PubMed

Rogerson, Thomas E; Ladhani, Maleeka; Mitchell, Ruth; Craig, Jonathan C; Webster, Angela C

2015-08-01

Nephrologists looking for quick answers to diagnostic clinical questions in MEDLINE can use a range of published search strategies or Clinical Query limits to improve the precision of their searches. We aimed to evaluate existing search strategies for finding diagnostic test accuracy studies in nephrology journals. We assessed the accuracy of 14 search strategies for retrieving diagnostic test accuracy studies from three nephrology journals indexed in MEDLINE. Two investigators hand searched the same journals to create a reference set of diagnostic test accuracy studies to compare search strategy results against. We identified 103 diagnostic test accuracy studies, accounting for 2.1% of all studies published. The most specific search strategy was the Narrow Clinical Queries limit (sensitivity: 0.20, 95% CI 0.13-0.29; specificity: 0.99, 95% CI 0.99-0.99). Using the Narrow Clinical Queries limit, a searcher would need to screen three (95% CI 2-6) articles to find one diagnostic study. The most sensitive search strategy was van der Weijden 1999 Extended (sensitivity: 0.95; 95% CI 0.89-0.98; specificity 0.55, 95% CI 0.53-0.56) but required a searcher to screen 24 (95% CI 23-26) articles to find one diagnostic study. Bachmann 2002 was the best balanced search strategy, which was sensitive (0.88, 95% CI 0.81-0.94), but also specific (0.74, 95% CI 0.73-0.75), with a number needed to screen of 15 (95% CI 14-17). Diagnostic studies are infrequently published in nephrology journals. The addition of a strategy for diagnostic studies to a subject search strategy in MEDLINE may reduce the records needed to screen while preserving adequate search sensitivity for routine clinical use. © 2015 Asian Pacific Society of Nephrology.

Ontario multidetector computed tomographic coronary angiography study: field evaluation of diagnostic accuracy.

PubMed

Chow, Benjamin J W; Freeman, Michael R; Bowen, James M; Levin, Leslie; Hopkins, Robert B; Provost, Yves; Tarride, Jean-Eric; Dennie, Carole; Cohen, Eric A; Marcuzzi, Dan; Iwanochko, Robert; Moody, Alan R; Paul, Narinder; Parker, John D; O'Reilly, Daria J; Xie, Feng; Goeree, Ron

2011-06-13

Computed tomographic coronary angiography (CTCA) has gained clinical acceptance for the detection of obstructive coronary artery disease. Although single-center studies have demonstrated excellent accuracy, multicenter studies have yielded variable results. The true diagnostic accuracy of CTCA in the "real world" remains uncertain. We conducted a field evaluation comparing multidetector CTCA with invasive CA (ICA) to understand CTCA's diagnostic accuracy in a real-world setting. A multicenter cohort study of patients awaiting ICA was conducted between September 2006 and June 2009. All patients had either a low or an intermediate pretest probability for coronary artery disease and underwent CTCA and ICA within 10 days. The results of CTCA and ICA were interpreted visually by local expert observers who were blinded to all clinical data and imaging results. Using a patient-based analysis (diameter stenosis ≥50%) of 169 patients, the sensitivity, specificity, positive predictive value, and negative predictive value were 81.3% (95% confidence interval [CI], 71.0%-89.1%), 93.3% (95% CI, 85.9%-97.5%), 91.6% (95% CI, 82.5%-96.8%), and 84.7% (95% CI, 76.0%-91.2%), respectively; the area under receiver operating characteristic curve was 0.873. The diagnostic accuracy varied across centers (P < .001), with a sensitivity, specificity, positive predictive value, and negative predictive value ranging from 50.0% to 93.2%, 92.0% to 100%, 84.6% to 100%, and 42.9% to 94.7%, respectively. Compared with ICA, CTCA appears to have good accuracy; however, there was variability in diagnostic accuracy across centers. Factors affecting institutional variability need to be better understood before CTCA is universally adopted. Additional real-world evaluations are needed to fully understand the impact of CTCA on clinical care. clinicaltrials.gov Identifier: NCT00371891.

Diagnostic accuracy of optical coherence tomography in actinic keratosis and basal cell carcinoma.

PubMed

Olsen, J; Themstrup, L; De Carvalho, N; Mogensen, M; Pellacani, G; Jemec, G B E

2016-12-01

Early diagnosis of non-melanoma skin cancer (NMSC) is potentially possible using optical coherence tomography (OCT) which provides non-invasive, real-time images of skin with micrometre resolution and an imaging depth of up to 2mm. OCT technology for skin imaging has undergone significant developments, improving image quality substantially. The diagnostic accuracy of any method is influenced by continuous technological development making it necessary to regularly re-evaluate methods. The objective of this study is to estimate the diagnostic accuracy of OCT in basal cell carcinomas (BCC) and actinic keratosis (AK) as well as differentiating these lesions from normal skin. A study set consisting of 142 OCT images meeting selection criterea for image quality and diagnosis of AK, BCC and normal skin was presented uniformly to two groups of blinded observers: 5 dermatologists experienced in OCT-image interpretation and 5 dermatologists with no experience in OCT. During the presentation of the study set the observers filled out a standardized questionnaire regarding the OCT diagnosis. Images were captured using a commercially available OCT machine (Vivosight ® , Michelson Diagnostics, UK). Skilled OCT observers were able to diagnose BCC lesions with a sensitivity of 86% to 95% and a specificity of 81% to 98%. Skilled observers with at least one year of OCT-experience showed an overall higher diagnostic accuracy compared to inexperienced observers. The study shows an improved diagnostic accuracy of OCT in differentiating AK and BCC from healthy skin using state-of-the-art technology compared to earlier OCT technology, especially concerning BCC diagnosis. Copyright © 2016 Elsevier B.V. All rights reserved.

Comparison of dermatoscopic diagnostic algorithms based on calculation: The ABCD rule of dermatoscopy, the seven-point checklist, the three-point checklist and the CASH algorithm in dermatoscopic evaluation of melanocytic lesions.

PubMed

Unlu, Ezgi; Akay, Bengu N; Erdem, Cengizhan

2014-07-01

Dermatoscopic analysis of melanocytic lesions using the CASH algorithm has rarely been described in the literature. The purpose of this study was to compare the sensitivity, specificity, and diagnostic accuracy rates of the ABCD rule of dermatoscopy, the seven-point checklist, the three-point checklist, and the CASH algorithm in the diagnosis and dermatoscopic evaluation of melanocytic lesions on the hairy skin. One hundred and fifteen melanocytic lesions of 115 patients were examined retrospectively using dermatoscopic images and compared with the histopathologic diagnosis. Four dermatoscopic algorithms were carried out for all lesions. The ABCD rule of dermatoscopy showed sensitivity of 91.6%, specificity of 60.4%, and diagnostic accuracy of 66.9%. The seven-point checklist showed sensitivity, specificity, and diagnostic accuracy of 87.5, 65.9, and 70.4%, respectively; the three-point checklist 79.1, 62.6, 66%; and the CASH algorithm 91.6, 64.8, and 70.4%, respectively. To our knowledge, this is the first study that compares the sensitivity, specificity and diagnostic accuracy of the ABCD rule of dermatoscopy, the three-point checklist, the seven-point checklist, and the CASH algorithm for the diagnosis of melanocytic lesions on the hairy skin. In our study, the ABCD rule of dermatoscopy and the CASH algorithm showed the highest sensitivity for the diagnosis of melanoma. © 2014 Japanese Dermatological Association.

Systematic review of dermoscopy and digital dermoscopy/ artificial intelligence for the diagnosis of melanoma.

PubMed

Rajpara, S M; Botello, A P; Townend, J; Ormerod, A D

2009-09-01

Dermoscopy improves diagnostic accuracy of the unaided eye for melanoma, and digital dermoscopy with artificial intelligence or computer diagnosis has also been shown useful for the diagnosis of melanoma. At present there is no clear evidence regarding the diagnostic accuracy of dermoscopy compared with artificial intelligence. To evaluate the diagnostic accuracy of dermoscopy and digital dermoscopy/artificial intelligence for melanoma diagnosis and to compare the diagnostic accuracy of the different dermoscopic algorithms with each other and with digital dermoscopy/artificial intelligence for the detection of melanoma. A literature search on dermoscopy and digital dermoscopy/artificial intelligence for melanoma diagnosis was performed using several databases. Titles and abstracts of the retrieved articles were screened using a literature evaluation form. A quality assessment form was developed to assess the quality of the included studies. Heterogeneity among the studies was assessed. Pooled data were analysed using meta-analytical methods and comparisons between different algorithms were performed. Of 765 articles retrieved, 30 studies were eligible for meta-analysis. Pooled sensitivity for artificial intelligence was slightly higher than for dermoscopy (91% vs. 88%; P = 0.076). Pooled specificity for dermoscopy was significantly better than artificial intelligence (86% vs. 79%; P < 0.001). Pooled diagnostic odds ratio was 51.5 for dermoscopy and 57.8 for artificial intelligence, which were not significantly different (P = 0.783). There were no significance differences in diagnostic odds ratio among the different dermoscopic diagnostic algorithms. Dermoscopy and artificial intelligence performed equally well for diagnosis of melanocytic skin lesions. There was no significant difference in the diagnostic performance of various dermoscopy algorithms. The three-point checklist, the seven-point checklist and Menzies score had better diagnostic odds ratios than the others; however, these results need to be confirmed by a large-scale high-quality population-based study.

Reporting completeness and transparency of meta-analyses of depression screening tool accuracy: A comparison of meta-analyses published before and after the PRISMA statement.

PubMed

Rice, Danielle B; Kloda, Lorie A; Shrier, Ian; Thombs, Brett D

2016-08-01

Meta-analyses that are conducted rigorously and reported completely and transparently can provide accurate evidence to inform the best possible healthcare decisions. Guideline makers have raised concerns about the utility of existing evidence on the diagnostic accuracy of depression screening tools. The objective of our study was to evaluate the transparency and completeness of reporting in meta-analyses of the diagnostic accuracy of depression screening tools using the PRISMA tool adapted for diagnostic test accuracy meta-analyses. We searched MEDLINE and PsycINFO from January 1, 2005 through March 13, 2016 for recent meta-analyses in any language on the diagnostic accuracy of depression screening tools. Two reviewers independently assessed the transparency in reporting using the PRISMA tool with appropriate adaptations made for studies of diagnostic test accuracy. We identified 21 eligible meta-analyses. Twelve of 21 meta-analyses complied with at least 50% of adapted PRISMA items. Of 30 adapted PRISMA items, 11 were fulfilled by ≥80% of included meta-analyses, 3 by 50-79% of meta-analyses, 7 by 25-45% of meta-analyses, and 9 by <25%. On average, post-PRISMA meta-analyses complied with 17 of 30 items compared to 13 of 30 items pre-PRISMA. Deficiencies in the transparency of reporting in meta-analyses of the diagnostic test accuracy of depression screening tools of meta-analyses were identified. Authors, reviewers, and editors should adhere to the PRISMA statement to improve the reporting of meta-analyses of the diagnostic accuracy of depression screening tools. Copyright © 2016 Elsevier Inc. All rights reserved.

Impact of time-resolved MRA on diagnostic accuracy in patients with symptomatic peripheral artery disease of the calf station.

PubMed

Hansmann, Jan; Michaely, Henrik J; Morelli, John N; Diehl, Steffen J; Meyer, Mathias; Schoenberg, Stefan O; Attenberger, Ulrike I

2013-12-01

The purpose of this article is to evaluate the added diagnostic accuracy of time-resolved MR angiography (MRA) of the calves compared with continuous-table-movement MRA in patients with symptomatic lower extremity peripheral artery disease (PAD) using digital subtraction angiography (DSA) correlation. Eighty-four consecutive patients with symptomatic PAD underwent a low-dose 3-T MRA protocol, consisting of continuous-table-movement MRA, acquired from the diaphragm to the calves, and an additional time-resolved MRA of the calves; 0.1 mmol/kg body weight (bw) of contrast material was used (0.07 mmol/kg bw for continuous-table-movement MRA and 0.03 mmol/kg bw for time-resolved MRA). Two radiologists rated image quality on a 4-point scale and stenosis degree on a 3-point scale. An additional assessment determined the degree of venous contamination and whether time-resolved MRA improved diagnostic confidence. The accuracy of stenosis gradation with continuous-table-movement and time-resolved MRA was compared with that of DSA as a correlation. Overall diagnostic accuracy was calculated for continuous-table-movement and time-resolved MRA. Median image quality was rated as good for 578 vessel segments with continuous-table-movement MRA and as excellent for 565 vessel segments with time-resolved MRA. Interreader agreement was excellent (κ = 0.80-0.84). Venous contamination interfered with diagnosis in more than 60% of continuous-table-movement MRA examinations. The degree of stenosis was assessed for 340 vessel segments. The diagnostic accuracies (continuous-table-movement MRA/time-resolved MRA) combined for the readers were obtained for the tibioperoneal trunk (84%/93%), anterior tibial (69%/87%), posterior tibial (85%/91%), and peroneal (67%/81%) arteries. The addition of time-resolved MRA improved diagnostic confidence in 69% of examinations. The addition of time-resolved MRA at the calf station improves diagnostic accuracy over continuous-table-movement MRA alone in symptomatic patients with PAD.

Diagnostic Accuracy of the Veteran Affairs' Traumatic Brain Injury Screen.

PubMed

Louise Bender Pape, Theresa; Smith, Bridget; Babcock-Parziale, Judith; Evans, Charlesnika T; Herrold, Amy A; Phipps Maieritsch, Kelly; High, Walter M

2018-01-31

To comprehensively estimate the diagnostic accuracy and reliability of the Department of Veterans Affairs (VA) Traumatic Brain Injury (TBI) Clinical Reminder Screen (TCRS). Cross-sectional, prospective, observational study using the Standards for Reporting of Diagnostic Accuracy criteria. Three VA Polytrauma Network Sites. Operation Iraqi Freedom, Operation Enduring Freedom veterans (N=433). TCRS, Comprehensive TBI Evaluation, Structured TBI Diagnostic Interview, Symptom Attribution and Classification Algorithm, and Clinician-Administered Posttraumatic Stress Disorder (PTSD) Scale. Forty-five percent of veterans screened positive on the TCRS for TBI. For detecting occurrence of historical TBI, the TCRS had a sensitivity of .56 to .74, a specificity of .63 to .93, a positive predictive value (PPV) of 25% to 45%, a negative predictive value (NPV) of 91% to 94%, and a diagnostic odds ratio (DOR) of 4 to 13. For accuracy of attributing active symptoms to the TBI, the TCRS had a sensitivity of .64 to .87, a specificity of .59 to .89, a PPV of 26% to 32%, an NPV of 92% to 95%, and a DOR of 6 to 9. The sensitivity was higher for veterans with PTSD (.80-.86) relative to veterans without PTSD (.57-.82). The specificity, however, was higher among veterans without PTSD (.75-.81) relative to veterans with PTSD (.36-.49). All indices of diagnostic accuracy changed when participants with questionably valid (QV) test profiles were eliminated from analyses. The utility of the TCRS to screen for mild TBI (mTBI) depends on the stringency of the diagnostic reference standard to which it is being compared, the presence/absence of PTSD, and QV test profiles. Further development, validation, and use of reproducible diagnostic algorithms for symptom attribution after possible mTBI would improve diagnostic accuracy. Published by Elsevier Inc.

Comparison between fine needle aspiration cytology (FNAC) and core needle biopsy (CNB) in the diagnosis of breast lesions.

PubMed

Moschetta, M; Telegrafo, M; Carluccio, D A; Jablonska, J P; Rella, L; Serio, Gabriella; Carrozzo, M; Stabile Ianora, A A; Angelelli, G

2014-01-01

To compare the diagnostic accuracy of fine-needle aspiration cytology (FNAC) and core needle biopsy (CNB) in patients with USdetected breast lesions. Between September 2011 and May 2013, 3469 consecutive breast US examinations were performed. 400 breast nodules were detected in 398 patients. 210 FNACs and 190 CNBs were performed. 183 out of 400 (46%) lesions were surgically removed within 30 days form diagnosis; in the remaining cases, a six month follow up US examination was performed. Sensitivity, specificity, diagnostic accuracy, positive predictive (PPV) and negative predictive (NPV) values were calculated for FNAC and CNB. 174 out of 400 (43%) malignant lesions were found while the remaining 226 resulted to be benign lesions. 166 out of 210 (79%) FNACs and 154 out of 190 (81%) CNBs provided diagnostic specimens. Sensitivity, specificity, diagnostic accuracy, PPV and NPV of 97%, 94%, 95%, 91% and 98% were found for FNAC, and values of 92%, 82%, 89%, 92% and 82% were obtained for CNB. Sensitivity, specificity, diagnostic accuracy, PPV and NPV of 97%, 96%, 96%, 97% and 96% were found for FNAC, and values of 97%, 96%, 96%, 97% and 96% were obtained for CNB. FNAC and CNB provide similar values of diagnostic accuracy.

Rectal cancer staging: Multidetector-row computed tomography diagnostic accuracy in assessment of mesorectal fascia invasion

PubMed Central

Ippolito, Davide; Drago, Silvia Girolama; Franzesi, Cammillo Talei; Fior, Davide; Sironi, Sandro

2016-01-01

AIM: To assess the diagnostic accuracy of multidetector-row computed tomography (MDCT) as compared with conventional magnetic resonance imaging (MRI), in identifying mesorectal fascia (MRF) invasion in rectal cancer patients. METHODS: Ninety-one patients with biopsy proven rectal adenocarcinoma referred for thoracic and abdominal CT staging were enrolled in this study. The contrast-enhanced MDCT scans were performed on a 256 row scanner (ICT, Philips) with the following acquisition parameters: tube voltage 120 KV, tube current 150-300 mAs. Imaging data were reviewed as axial and as multiplanar reconstructions (MPRs) images along the rectal tumor axis. MRI study, performed on 1.5 T with dedicated phased array multicoil, included multiplanar T2 and axial T1 sequences and diffusion weighted images (DWI). Axial and MPR CT images independently were compared to MRI and MRF involvement was determined. Diagnostic accuracy of both modalities was compared and statistically analyzed. RESULTS: According to MRI, the MRF was involved in 51 patients and not involved in 40 patients. DWI allowed to recognize the tumor as a focal mass with high signal intensity on high b-value images, compared with the signal of the normal adjacent rectal wall or with the lower tissue signal intensity background. The number of patients correctly staged by the native axial CT images was 71 out of 91 (41 with involved MRF; 30 with not involved MRF), while by using the MPR 80 patients were correctly staged (45 with involved MRF; 35 with not involved MRF). Local tumor staging suggested by MDCT agreed with those of MRI, obtaining for CT axial images sensitivity and specificity of 80.4% and 75%, positive predictive value (PPV) 80.4%, negative predictive value (NPV) 75% and accuracy 78%; while performing MPR the sensitivity and specificity increased to 88% and 87.5%, PPV was 90%, NPV 85.36% and accuracy 88%. MPR images showed higher diagnostic accuracy, in terms of MRF involvement, than native axial images, as compared to the reference magnetic resonance images. The difference in accuracy was statistically significant (P = 0.02). CONCLUSION: New generation CT scanner, using high resolution MPR images, represents a reliable diagnostic tool in assessment of loco-regional and whole body staging of advanced rectal cancer, especially in patients with MRI contraindications. PMID:27239115

Diagnostic Accuracy of Cerebrospinal Fluid Amyloid-β Isoforms for Early and Differential Dementia Diagnosis.

PubMed

Struyfs, Hanne; Van Broeck, Bianca; Timmers, Maarten; Fransen, Erik; Sleegers, Kristel; Van Broeckhoven, Christine; De Deyn, Peter P; Streffer, Johannes R; Mercken, Marc; Engelborghs, Sebastiaan

2015-01-01

Overlapping cerebrospinal fluid biomarkers (CSF) levels between Alzheimer's disease (AD) and non-AD patients decrease differential diagnostic accuracy of the AD core CSF biomarkers. Amyloid-β (Aβ) isoforms might improve the AD versus non-AD differential diagnosis. To determine the added diagnostic value of Aβ isoforms, Aβ(1-37), Aβ(1-38), and Aβ(1-40), as compared to the AD CSF biomarkers Aβ(1-42), T-tau, and P-tau(181P). CSF from patients with dementia due to AD (n = 50), non-AD dementias (n = 50), mild cognitive impairment due to AD (n = 50) and non-demented controls (n = 50) was analyzed with a prototype multiplex assay using MSD detection technology. The non-AD group consisted of frontotemporal dementia (FTD; n = 17), dementia with Lewy bodies (DLB; n = 17), and vascular dementia (n = 16). Aβ(1-37) and Aβ(1-38) increased accuracy to differentiate AD from FTD or DLB. Aβ(1-37), Aβ(1-38), and Aβ(1-40) levels correlated with Mini-Mental State Examination scores and disease duration in dementia due to AD. The Aβ(1-42)/Aβ(1-40) ratio improved diagnostic performance of Aβ(1-42) in most differential diagnostic situations. Aβ(1-42) levels were lower in APOE ε4 carriers compared to non-carriers. Aβ isoforms help to differentiate AD from FTD and DLB. Aβ isoforms increase diagnostic performance of Aβ(1-42). In contrast to Aβ1-42, Aβ isoforms seem to be correlated with disease severity in AD. Adding the Aβ isoforms to the current biomarker panel could enhance diagnostic accuracy.

Get the Diagnosis: an evidence-based medicine collaborative Wiki for diagnostic test accuracy.

PubMed

Hammer, Mark M; Kohlberg, Gavriel D

2017-04-01

Despite widespread calls for its use, there are challenges to the implementation of evidence-based medicine (EBM) in clinical practice. In response to the challenges of finding timely, pertinent information on diagnostic test accuracy, we developed an online, crowd-sourced Wiki on diagnostic test accuracy called Get the Diagnosis (GTD, http://www.getthediagnosis.org). Since its launch in November 2008 till October 2015, GTD has accumulated information on 300 diagnoses, with 1617 total diagnostic entries. There are a total of 1097 unique diagnostic tests with a mean of 5.4 tests (range 0-38) per diagnosis. 73% of entries (1182 of 1617) have an associated sensitivity and specificity and 89% of entries (1432 of 1617) have associated peer-reviewed literature citations. Altogether, GTD contains 474 unique literature citations. For a sample of three diagnoses, the search precision (percentage of relevant results in the first 30 entries) in GTD was 100% as compared with a range of 13.3%-63.3% for PubMed and between 6.7% and 76.7% for Google Scholar. GTD offers a fast, precise and efficient way to look up diagnostic test accuracy. On three selected examples, GTD had a greater precision rate compared with PubMed and Google Scholar in identifying diagnostic test information. GTD is a free resource that complements other currently available resources. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

Sonography of the chest using linear-array versus sector transducers: Correlation with auscultation, chest radiography, and computed tomography.

PubMed

Tasci, Ozlem; Hatipoglu, Osman Nuri; Cagli, Bekir; Ermis, Veli

2016-07-08

The primary purpose of our study was to compare the efficacies of two sonographic (US) probes, a high-frequency linear-array probe and a lower-frequency phased-array sector probe in the diagnosis of basic thoracic pathologies. The secondary purpose was to compare the diagnostic performance of thoracic US with auscultation and chest radiography (CXR) using thoracic CT as a gold standard. In total, 55 consecutive patients scheduled for thoracic CT were enrolled in this prospective study. Four pathologic entities were evaluated: pneumothorax, pleural effusion, consolidation, and interstitial syndrome. A portable US scanner was used with a 5-10-MHz linear-array probe and a 1-5-MHz phased-array sector probe. The first probe used was chosen randomly. US, CXR, and auscultation results were compared with the CT results. The linear-array probe had the highest performance in the identification of pneumothorax (83% sensitivity, 100% specificity, and 99% diagnostic accuracy) and pleural effusion (100% sensitivity, 97% specificity, and 98% diagnostic accuracy); the sector probe had the highest performance in the identification of consolidation (89% sensitivity, 100% specificity, and 95% diagnostic accuracy) and interstitial syndrome (94% sensitivity, 93% specificity, and 94% diagnostic accuracy). For all pathologies, the performance of US was superior to those of CXR and auscultation. The linear probe is superior to the sector probe for identifying pleural pathologies, whereas the sector probe is superior to the linear probe for identifying parenchymal pathologies. Thoracic US has better diagnostic performance than CXR and auscultation for the diagnosis of common pathologic conditions of the chest. © 2016 Wiley Periodicals, Inc. J Clin Ultrasound 44:383-389, 2016. © 2016 Wiley Periodicals, Inc.

Comparison and validation of International Consensus Diagnostic Criteria for diagnosis of autoimmune pancreatitis from pancreatic cancer in a Taiwanese cohort.

PubMed

Chang, Ming-Chu; Liang, Po-Chin; Jan, I-Shiow; Yang, Ching-Yao; Tien, Yu-Wen; Wei, Shu-Chen; Wong, Jau-Min; Chang, Yu-Ting

2014-08-18

The International Consensus Diagnostic Criteria (ICDC) designed to diagnosis autoimmune pancreatitis (AIP) has been proposed recently. The diagnostic performance of ICDC has not been previously evaluated in diffuse-type and focal-type AIP, respectively, in comparison with the revised HISORt and Asian criteria in Taiwan. Prospective, consecutive patient cohort. Largest tertiary referred centre hospital managing pancreatic disease in Taiwan. 188 patients with AIP and 130 with tissue proofed pancreatic adenocarcinoma were consecutively recruited. The ICDC, as well as revised HISORt and Asian criteria, was applied for each participant. Each diagnostic criterion of ICDC was validated with special reference to levels 1 and 2 in diffuse-type and focal-type AIP. Sensitivity, specificity and accuracy. Each diagnostic criterion of ICDC was validated with special reference to levels 1 and 2 in AIP and focal-type AIP. The sensitivity, specificity and accuracy of ICDC for all AIP were the best: 89.4%, 100% and 93.7%, respectively, in these three criteria. The sensitivity, specificity and accuracy of ICDC for focal-type AIP (84.9%, 100% and 93.8%) were also the best among these three criteria. The area under the curve of receiver-operator characteristic of ICDC was 0.95 (95% CI 0.92 to 0.97) in all AIP and 0.93 (95% CI 0.88 to 0.97) in focal-type AIP. The sensitivity, specificity and accuracy of ICDC are higher than the revised HISORt and Asian criteria. The sensitivity, specificity and accuracy of each criterion are higher in diffuse-type AIP compared with focal-type AIP. Under the same specificity, the sensitivity and accuracy of ICDC are higher than other diagnostic criteria in focal-type AIP. ICDC has better diagnostic performance compared with previously proposed diagnostic criteria in diffuse-type and focal-type AIP. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

The value of rapid on-site evaluation during EBUS-TBNA.

PubMed

Cardoso, A V; Neves, I; Magalhães, A; Sucena, M; Barroca, H; Fernandes, G

2015-01-01

Rapid on-site evaluation (ROSE) has the potential to increase endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) accuracy in the diagnosis of mediastinal lesions and lung cancer staging. However, studies have reported controversial results. The purpose of our study was to evaluate the influence of ROSE on sample adequacy and diagnostic accuracy of EBUS-TBNA. Prospective observational study that enrolled 81 patients who underwent EBUS-TBNA for investigation of hilo-mediastinal lesions or lung cancer staging. The first 41 patients underwent EBUS-TBNA with ROSE (ROSE group) and the last 40 patients without ROSE (non-ROSE group). Sample adequacy and diagnostic accuracy of EBUS-TBNA in both groups were compared. Adequate samples were obtained in 93% of the patients in the ROSE group and 80% in non-ROSE group (p=0.10). The diagnostic accuracy of EBUS-TBNA was 91% in ROSE group and 83% in non-ROSE group (p=0.08). Analyzing the EBUS-TBNA purpose, in the subgroup of patients who underwent EBUS-TBNA for investigation of hilo-mediastinal lesions, these differences between ROSE and non-ROSE group were higher compared to lung cancer staging, 93% of patients with adequate samples in the ROSE group vs. 75% in the non-ROSE group (p=0.06) and 87% of diagnostic accuracy in ROSE group vs. 77% in non-ROSE group (p=0.10). Despite the lack of statistical significance, ROSE appears to be particularly useful in the diagnostic work-up of hilo-mediastinal lesions, increasing the diagnostic yield of EBUS-TBNA. Copyright © 2014 Sociedade Portuguesa de Pneumologia. Published by Elsevier España, S.L.U. All rights reserved.

Allergen extracts and recombinant proteins: comparison of efficiency of in vitro allergy diagnostics using multiplex assay on a biological microchip.

PubMed

Smoldovskaya, Olga; Feyzkhanova, Guzel; Arefieva, Alla; Voloshin, Sergei; Ivashkina, Olga; Reznikov, Yuriy; Rubina, Alla

2016-01-01

Immunological test systems for diagnostics of type I hypersensitivity involve the following types of antigens: whole allergen extracts, individual highly purified proteins and their recombinant analogues. The goal of this study was to compare the results obtained with whole allergen extracts (birch pollen, cat dander, and timothy grass pollen) and their respective recombinant proteins in biochip-based immunoassay. Multiplex fluorescent immunoassay of 139 patients' blood serum samples was carried out using biological microchips (biochips). sIgE concentrations for the chosen allergens and their recombinant components were measured. ROC analysis was used for comparison of the results and determination of diagnostic accuracy. The results for the birch pollen extract and its recombinant allergens have shown that the diagnostic accuracy of the methods utilizing the whole allergen extract, its major component Bet v 1 and the combination of major and minor components (Bet v 1 and Bet v 2) was the same. Values for diagnostic accuracy for the cat dander extract and its major recombinant component Fel d 1 were equal. In contrast with birch pollen and cat dander allergens, using of recombinant components of timothy grass pollen (Phl p 1, Phl p 5, Phl p 7 and Phl p 12) did not allow reaching the diagnostic accuracy of using natural extract. Multiplex analysis of samples obtained from patients with allergy to birch pollen and cat dander using biological microchips has shown that comparable accuracy was observed for the assay with natural extracts and recombinant allergens. In the case of timothy grass allergen, using the recombinant components may be insufficient.

The Screening Accuracy of the Parent and Teacher-Reported Social Responsiveness Scale (SRS): Comparison with the 3Di and ADOS

ERIC Educational Resources Information Center

Duvekot, Jorieke; van der Ende, Jan; Verhulst, Frank C.; Greaves-Lord, Kirstin

2015-01-01

The screening accuracy of the parent and teacher-reported Social Responsiveness Scale (SRS) was compared with an autism spectrum disorder (ASD) classification according to (1) the Developmental, Dimensional, and Diagnostic Interview (3Di), (2) the Autism Diagnostic Observation Schedule (ADOS), (3) both the 3Di and ADOS, in 186 children referred to…

Meta-analysis of stratus OCT glaucoma diagnostic accuracy.

PubMed

Chen, Hsin-Yi; Chang, Yue-Cune

2014-09-01

To evaluate the diagnostic accuracy of glaucoma in different stages, different types of glaucoma, and different ethnic groups using Stratus optical coherence tomography (OCT). We searched MEDLINE to identify available articles on diagnostic accuracy of glaucoma published between January 2004 and December 2011. A PubMed (National Center for Biotechnology Information) search using medical subject headings and keywords was executed using the following terms: "diagnostic accuracy" or "receiver operator characteristic" or "area under curve" or "AUC" and "Stratus OCT" and "glaucoma." The search was subsequently limited to publications in English. The area under a receiver operator characteristic (AUC) curve was used to measure the diagnostic performance. A random-effects model was used to estimate the pooled AUC value of the 17 parameters (average retinal nerve fiber layer thickness, temporal quadrant, superior quadrant, nasal quadrant, inferior quadrant, and 1 to 12 o'clock). Meta-regression analysis was used to check the significance of some important factors: (1) glaucoma severity (five stages), (2) glaucoma types (four types), and (3) ethnicity (four categories). The orders of accuracy among those parameters were as follows: average > inferior > superior > 7 o'clock > 6 o'clock > 11 o'clock > 12 o'clock > 1 o'clock > 5 o'clock > nasal > temporal > 2 o'clock > 10 o'clock > 8 o'clock > 9 o'clock > 4 o'clock > 3 o'clock. After adjusting for the effects of age, glaucoma severity, glaucoma types, and ethnicity, the average retinal nerve fiber layer thickness provided highest accuracy compared with the other parameters of OCT. The diagnostic accuracy in Asian populations was significantly lower than that in whites and the other two ethnic types. Stratus OCT demonstrated good diagnostic capability in differentiating glaucomatous from normal eyes. However, we should be more cautious in applying this instrument in Asian groups in glaucoma management.

A Statistical Evaluation of the Diagnostic Performance of MEDAS-The Medical Emergency Decision Assistance System

PubMed Central

Georgakis, D. Christine; Trace, David A.; Naeymi-Rad, Frank; Evens, Martha

1990-01-01

Medical expert systems require comprehensive evaluation of their diagnostic accuracy. The usefulness of these systems is limited without established evaluation methods. We propose a new methodology for evaluating the diagnostic accuracy and the predictive capacity of a medical expert system. We have adapted to the medical domain measures that have been used in the social sciences to examine the performance of human experts in the decision making process. Thus, in addition to the standard summary measures, we use measures of agreement and disagreement, and Goodman and Kruskal's λ and τ measures of predictive association. This methodology is illustrated by a detailed retrospective evaluation of the diagnostic accuracy of the MEDAS system. In a study using 270 patients admitted to the North Chicago Veterans Administration Hospital, diagnoses produced by MEDAS are compared with the discharge diagnoses of the attending physicians. The results of the analysis confirm the high diagnostic accuracy and predictive capacity of the MEDAS system. Overall, the agreement of the MEDAS system with the “gold standard” diagnosis of the attending physician has reached a 90% level.

Diagnostic accuracy of magnetic resonance imaging, transvaginal, and transrectal ultrasonography in deep infiltrating endometriosis

PubMed Central

Alborzi, Saeed; Rasekhi, Alireza; Shomali, Zahra; Madadi, Gooya; Alborzi, Mahshid; Kazemi, Mahboobeh; Hosseini Nohandani, Azam

2018-01-01

Abstract To determine the diagnostic accuracy of pelvic magnetic resonance imaging (MRI), transvaginal sonography (TVS), and transrectal sonography (TRS) in diagnosis of deep infiltrating endometriosis (DIE). This diagnostic accuracy study was conducted during a 2-year period including a total number of 317 patients with signs and symptoms of endometriosis. All the patients were evaluated by pelvic MRI, TVS, and TRS in the same center. The criterion standard was considered to be the laparoscopy and histopathologic examination. Of 317 patients being included in the present study, 252 tested positive for DIE. The sensitivity, specificity, positive predictive value, and negative predictive value of TVS was found to be 83.3%, 46.1%, 85.7%, and 41.6%, respectively. These variables were 80.5%, 18.6%, 79.3%, and 19.7% for TRS and 90.4%, 66.1%, 91.2%, and 64.1% for MRI, respectively. MRI had the highest accuracy (85.4%) when compared to TVS (75.7%) and TRS (67.8%). The sensitivity of TRS, TVS, and MRI in uterosacral ligament DIE was 82.8%, 70.9%, and 63.6%, respectively. On the contrary, specificity had a reverse trend, favoring MRI (93.9%, 92.8%, and 89.8% for TVS and TRS, respectively). The results of the present study demonstrated that TVS and TRS have appropriate diagnostic accuracy in diagnosis of DIE comparable to MRI. PMID:29465552

The German version of the Posttraumatic Stress Disorder Checklist for DSM-5 (PCL-5): psychometric properties and diagnostic utility.

PubMed

Krüger-Gottschalk, Antje; Knaevelsrud, Christine; Rau, Heinrich; Dyer, Anne; Schäfer, Ingo; Schellong, Julia; Ehring, Thomas

2017-11-28

The Posttraumatic Stress Disorder (PTSD) Checklist (PCL, now PCL-5) has recently been revised to reflect the new diagnostic criteria of the disorder. A clinical sample of trauma-exposed individuals (N = 352) was assessed with the Clinician Administered PTSD Scale for DSM-5 (CAPS-5) and the PCL-5. Internal consistencies and test-retest reliability were computed. To investigate diagnostic accuracy, we calculated receiver operating curves. Confirmatory factor analyses (CFA) were performed to analyze the structural validity. Results showed high internal consistency (α = .95), high test-retest reliability (r = .91) and a high correlation with the total severity score of the CAPS-5, r = .77. In addition, the recommended cutoff of 33 on the PCL-5 showed high diagnostic accuracy when compared to the diagnosis established by the CAPS-5. CFAs comparing the DSM-5 model with alternative models (the three-factor solution, the dysphoria, anhedonia, externalizing behavior and hybrid model) to account for the structural validity of the PCL-5 remained inconclusive. Overall, the findings show that the German PCL-5 is a reliable instrument with good diagnostic accuracy. However, more research evaluating the underlying factor structure is needed.

QUADAS and STARD: evaluating the quality of diagnostic accuracy studies.

PubMed

Oliveira, Maria Regina Fernandes de; Gomes, Almério de Castro; Toscano, Cristiana Maria

2011-04-01

To compare the performance of two approaches, one based on the Quality Assessment of Diagnostic Accuracy Studies (QUADAS) and another on the Standards for Reporting Studies of Diagnostic Accuracy (STARD), in evaluating the quality of studies validating the OptiMal® rapid malaria diagnostic test. Articles validating the rapid test published until 2007 were searched in the Medline/PubMed database. This search retrieved 13 articles. A combination of 12 QUADAS criteria and three STARD criteria were compared with the 12 QUADAS criteria alone. Articles that fulfilled at least 50% of QUADAS criteria were considered as regular to good quality. Of the 13 articles retrieved, 12 fulfilled at least 50% of QUADAS criteria, and only two fulfilled the STARD/QUADAS criteria combined. Considering the two criteria combination (> 6 QUADAS and > 3 STARD), two studies (15.4%) showed good methodological quality. The articles selection using the proposed combination resulted in two to eight articles, depending on the number of items assumed as cutoff point. The STARD/QUADAS combination has the potential to provide greater rigor when evaluating the quality of studies validating malaria diagnostic tests, given that it incorporates relevant information not contemplated in the QUADAS criteria alone.

Combining functional and structural tests improves the diagnostic accuracy of relevance vector machine classifiers

PubMed Central

Racette, Lyne; Chiou, Christine Y.; Hao, Jiucang; Bowd, Christopher; Goldbaum, Michael H.; Zangwill, Linda M.; Lee, Te-Won; Weinreb, Robert N.; Sample, Pamela A.

2009-01-01

Purpose To investigate whether combining optic disc topography and short-wavelength automated perimetry (SWAP) data improves the diagnostic accuracy of relevance vector machine (RVM) classifiers for detecting glaucomatous eyes compared to using each test alone. Methods One eye of 144 glaucoma patients and 68 healthy controls from the Diagnostic Innovations in Glaucoma Study were included. RVM were trained and tested with cross-validation on optimized (backward elimination) SWAP features (thresholds plus age; pattern deviation (PD); total deviation (TD)) and on Heidelberg Retina Tomograph II (HRT) optic disc topography features, independently and in combination. RVM performance was also compared to two HRT linear discriminant functions (LDF) and to SWAP mean deviation (MD) and pattern standard deviation (PSD). Classifier performance was measured by the area under the receiver operating characteristic curves (AUROCs) generated for each feature set and by the sensitivities at set specificities of 75%, 90% and 96%. Results RVM trained on combined HRT and SWAP thresholds plus age had significantly higher AUROC (0.93) than RVM trained on HRT (0.88) and SWAP (0.76) alone. AUROCs for the SWAP global indices (MD: 0.68; PSD: 0.72) offered no advantage over SWAP thresholds plus age, while the LDF AUROCs were significantly lower than RVM trained on the combined SWAP and HRT feature set and on HRT alone feature set. Conclusions Training RVM on combined optimized HRT and SWAP data improved diagnostic accuracy compared to training on SWAP and HRT parameters alone. Future research may identify other combinations of tests and classifiers that can also improve diagnostic accuracy. PMID:19528827

Diagnostic value of rectal suction biopsies using calretinin immunohistochemical staining in Hirschsprung's disease.

PubMed

Tran, Viet Quoc; Lam, Kim Thien; Truong, Dinh Quang; Dang, Minh Hoang; Doan, Thao Thi Phuong; Segers, Valerie; Butler, Marilyn West; Robert, Annie; Goyens, Philippe; Steyaert, Henri

2016-12-01

The study investigates the diagnostic value of calretinin immunohistochemical staining (CIS) on rectal suction biopsies (RSB) in Hirschsprung's disease (HD). A prospective study was conducted at Children's Hospital 2 in Ho Chi Minh City, Vietnam, from January through December 2015. Patients suspected of HD during this period underwent RSB and were followed in order to assess the accuracy of the diagnostic test with CIS compared with conventional histology (H&E). A total of 188 children with RSB were investigated. Median age was 7.1 (range 0.2-159) months with 65.4% boys. HD was confirmed in 80 (42.6%) children. There were 1 false positive and no false-negative cases. The sensitivity and specificity were 100% (80/80) and 99.1% (107/108) for CIS and 100% and 85.2% for H&E, respectively. Cohen's kappa coefficient was 0.9891 with a diagnostic accuracy of 99.5% for CIS, compared with 0.8303 and 91.5% for H&E, respectively. There were no serious complications related to the RSB. RSB with CIS is a useful diagnostic method for HD, with easy interpretation and no need for cryostat. CIS has a high diagnostic accuracy and should be considered as the primary method for the diagnosis of HD by RSB. Diagnostic Studies - Level I. Copyright © 2016 Elsevier Inc. All rights reserved.

Diagnostic Accuracy of the Neck Tornado Test as a New Screening Test in Cervical Radiculopathy.

PubMed

Park, Juyeon; Park, Woo Young; Hong, Seungbae; An, Jiwon; Koh, Jae Chul; Lee, Youn-Woo; Kim, Yong Chan; Choi, Jong Bum

2017-01-01

The Spurling test, although a highly specific provocative test of the cervical spine in cervical radiculopathy (CR), has low to moderate sensitivity. Thus, we introduced the neck tornado test (NTT) to examine the neck and the cervical spine in CR. The aim of this study was to introduce a new provocative test, the NTT, and compare the diagnostic accuracy with a widely accepted provocative test, the Spurling test. Retrospective study. Medical records of 135 subjects with neck pain (CR, n = 67; without CR, n = 68) who had undergone cervical spine magnetic resonance imaging and been referred to the pain clinic between September 2014 and August 2015 were reviewed. Both the Spurling test and NTT were performed in all patients by expert examiners. Sensitivity, specificity, and accuracy were compared for both the Spurling test and the NTT. The sensitivity of the Spurling test and the NTT was 55.22% and 85.07% ( P < 0.0001); specificity, 98.53% and 86.76% ( P = 0.0026); accuracy, 77.04% and 85.93% ( P = 0.0423), respectively. The NTT is more sensitive with superior diagnostic accuracy for CR diagnosed by magnetic resonance imaging than the Spurling test.

Accuracy of ultra-wide-field fundus ophthalmoscopy-assisted deep learning, a machine-learning technology, for detecting age-related macular degeneration.

PubMed

Matsuba, Shinji; Tabuchi, Hitoshi; Ohsugi, Hideharu; Enno, Hiroki; Ishitobi, Naofumi; Masumoto, Hiroki; Kiuchi, Yoshiaki

2018-05-09

To predict exudative age-related macular degeneration (AMD), we combined a deep convolutional neural network (DCNN), a machine-learning algorithm, with Optos, an ultra-wide-field fundus imaging system. First, to evaluate the diagnostic accuracy of DCNN, 364 photographic images (AMD: 137) were amplified and the area under the curve (AUC), sensitivity and specificity were examined. Furthermore, in order to compare the diagnostic abilities between DCNN and six ophthalmologists, we prepared yield 84 sheets comprising 50% of normal and wet-AMD data each, and calculated the correct answer rate, specificity, sensitivity, and response times. DCNN exhibited 100% sensitivity and 97.31% specificity for wet-AMD images, with an average AUC of 99.76%. Moreover, comparing the diagnostic abilities of DCNN versus six ophthalmologists, the average accuracy of the DCNN was 100%. On the other hand, the accuracy of ophthalmologists, determined only by Optos images without a fundus examination, was 81.9%. A combination of DCNN with Optos images is not better than a medical examination; however, it can identify exudative AMD with a high level of accuracy. Our system is considered useful for screening and telemedicine.

Comparing the Diagnostic Accuracy of Six Potential Screening Instruments for Bipolar Disorder in Youths Aged 5 to 17 Years.

ERIC Educational Resources Information Center

Youngstrom, Eric A.; Findling, Robert L.; Calabrese, Joseph R.; Gracious, Barbara L.; Demeter, Christine; DelPorto Bedoya, Denise; Price, Megan

2004-01-01

Objective: To compare the diagnostic efficiency of six index tests as predictors of juvenile bipolar disorder in two large outpatient samples, aged 5 to 10 and 11 to 17 years, gathered from 1997 to 2002. Method: DSM-IV diagnosis was based on a semistructured diagnostic interview (Schedule for Affective Disorders and Schizophrenia for School-Age…

The Effects of Q-Matrix Design on Classification Accuracy in the Log-Linear Cognitive Diagnosis Model.

PubMed

Madison, Matthew J; Bradshaw, Laine P

2015-06-01

Diagnostic classification models are psychometric models that aim to classify examinees according to their mastery or non-mastery of specified latent characteristics. These models are well-suited for providing diagnostic feedback on educational assessments because of their practical efficiency and increased reliability when compared with other multidimensional measurement models. A priori specifications of which latent characteristics or attributes are measured by each item are a core element of the diagnostic assessment design. This item-attribute alignment, expressed in a Q-matrix, precedes and supports any inference resulting from the application of the diagnostic classification model. This study investigates the effects of Q-matrix design on classification accuracy for the log-linear cognitive diagnosis model. Results indicate that classification accuracy, reliability, and convergence rates improve when the Q-matrix contains isolated information from each measured attribute.

Can mandibular bone resorption predict hip fracture in elderly women? A systematic review of diagnostic test accuracy.

PubMed

Devlin, Hugh; Whelton, Christopher

2015-09-01

The aim of this systematic review was to determine the diagnostic accuracy of the mandibular cortical width measurements and porosity in detecting hip osteoporosis. All of the included studies used measurements on panoramic radiographs. Studies were included if they compared the radiographic measurements (or index tests) with central dual energy X-ray absorptiometry (DXA) of the hip as the reference standard. A measure of diagnostic accuracy such as sensitivity and specificity or area under the receiver operating characteristic curve was also required for inclusion. Seven studies were identified. Meta-analysis was not possible because of the heterogeneity of the studies. The studies all demonstrated moderate diagnostic accuracy. If a patient with a thin or porous mandibular cortex is identified by a chance radiographic finding, additional clinical risk factors need to be considered and the patient referred for further investigation with DXA where necessary. © 2013 John Wiley & Sons A/S and The Gerodontology Society. Published by John Wiley & Sons Ltd.

Pooled diagnostic accuracy of resting distal to aortic coronary pressure referenced to fractional flow reserve: The importance of resting coronary physiology.

PubMed

Maini, Rohit; Moscona, John; Sidhu, Gursukhman; Katigbak, Paul; Fernandez, Camilo; Irimpen, Anand; Mogabgab, Owen; Ward, Charisse; Samson, Rohan; LeJemtel, Thierry

2018-04-29

Both resting and hyperemic physiologic methods to guide coronary revascularization improve cardiovascular outcomes compared with angiographic guidance alone. Fractional flow reserve (FFR) remains underutilized due to concerns regarding hyperemia, prompting study of resting distal to aortic coronary pressure (Pd/Pa). Pd/Pa is a vasodilator-free resting index unlike FFR. While Pd/Pa is similar to another resting index, instantaneous wave-free ratio (iFR), it is a whole-cycle measurement not limited to the wave-free diastolic period. Pd/Pa is not validated clinically although multiple accuracy studies have been performed. Our meta-analysis examines the overall diagnostic accuracy of Pd/Pa referenced to FFR, the accepted invasive standard of ischemia. We searched PubMed, EMBASE, Central, ProQuest, and Web of Science databases for full text articles published through August 9, 2017 addressing the diagnostic accuracy of Pd/Pa referenced to FFR < 0.80. The following keywords were used: "distal coronary artery pressure" OR "Pd/Pa" AND "fractional flow reserve" OR "FFR." In total, 14 studies comprising 7004 lesions were identified. Pooled diagnostic accuracy estimates of Pd/Pa versus FFR < 0.80 were: sensitivity, 0.77 (95% CI, 0.75-0.78); specificity, 0.82 (0.81-0.83); positive likelihood ratio, 4.7 (3.3-6.6); negative likelihood ratio, 0.29 (0.24-0.34); diagnostic odds ratio, 18.1 (14.4-22.6); area under the summary receiver-operating characteristic curve of 0.88; and diagnostic accuracy of 0.80 (0.76-0.83). Pd/Pa shows adequate agreement with FFR as a resting index of coronary stenosis severity without the undesired effects and cost of hyperemic agents. Pd/Pa has the potential to guide coronary revascularization with easier application and availability compared with iFR and FFR. © 2018, Wiley Periodicals, Inc.

Diagnostic Performance of a Novel Coronary CT Angiography Algorithm: Prospective Multicenter Validation of an Intracycle CT Motion Correction Algorithm for Diagnostic Accuracy.

PubMed

Andreini, Daniele; Lin, Fay Y; Rizvi, Asim; Cho, Iksung; Heo, Ran; Pontone, Gianluca; Bartorelli, Antonio L; Mushtaq, Saima; Villines, Todd C; Carrascosa, Patricia; Choi, Byoung Wook; Bloom, Stephen; Wei, Han; Xing, Yan; Gebow, Dan; Gransar, Heidi; Chang, Hyuk-Jae; Leipsic, Jonathon; Min, James K

2018-06-01

Motion artifact can reduce the diagnostic accuracy of coronary CT angiography (CCTA) for coronary artery disease (CAD). The purpose of this study was to compare the diagnostic performance of an algorithm dedicated to correcting coronary motion artifact with the performance of standard reconstruction methods in a prospective international multicenter study. Patients referred for clinically indicated invasive coronary angiography (ICA) for suspected CAD prospectively underwent an investigational CCTA examination free from heart rate-lowering medications before they underwent ICA. Blinded core laboratory interpretations of motion-corrected and standard reconstructions for obstructive CAD (≥ 50% stenosis) were compared with ICA findings. Segments unevaluable owing to artifact were considered obstructive. The primary endpoint was per-subject diagnostic accuracy of the intracycle motion correction algorithm for obstructive CAD found at ICA. Among 230 patients who underwent CCTA with the motion correction algorithm and standard reconstruction, 92 (40.0%) had obstructive CAD on the basis of ICA findings. At a mean heart rate of 68.0 ± 11.7 beats/min, the motion correction algorithm reduced the number of nondiagnostic scans compared with standard reconstruction (20.4% vs 34.8%; p < 0.001). Diagnostic accuracy for obstructive CAD with the motion correction algorithm (62%; 95% CI, 56-68%) was not significantly different from that of standard reconstruction on a per-subject basis (59%; 95% CI, 53-66%; p = 0.28) but was superior on a per-vessel basis: 77% (95% CI, 74-80%) versus 72% (95% CI, 69-75%) (p = 0.02). The motion correction algorithm was superior in subgroups of patients with severely obstructive (≥ 70%) stenosis, heart rate ≥ 70 beats/min, and vessels in the atrioventricular groove. The motion correction algorithm studied reduces artifacts and improves diagnostic performance for obstructive CAD on a per-vessel basis and in selected subgroups on a per-subject basis.

A Brief Report of the Diagnostic Accuracy of Oral Reading Fluency and Reading Inventory Levels for Reading Failure Risk among Second- and Third-Grade Students

ERIC Educational Resources Information Center

Parker, David C.; Zaslofsky, Anne F.; Burns, Matthew K.; Kanive, Rebecca; Hodgson, Jennifer; Scholin, Sarah E.; Klingbeil, David A.

2015-01-01

The availability of psychometrically sound and usable universal screeners is a key component to successful early identification within a response-to-intervention model. The purpose of this study was to compare the diagnostic accuracy of oral reading fluency (ORF) and an informal reading inventory for identifying students considered at risk for…

How to tell a patient's story? Influence of the case narrative design on the clinical reasoning process in virtual patients.

PubMed

Hege, Inga; Dietl, Anita; Kiesewetter, Jan; Schelling, Jörg; Kiesewetter, Isabel

2018-02-28

Virtual patients (VPs) are narrative-based educational activities to train clinical reasoning in a safe environment. Our aim was to explore the influence of the design of the narrative and level of difficulty on the clinical reasoning process, diagnostic accuracy and time-on-task. In a randomized controlled trial, we analyzed the clinical reasoning process of 46 medical students with six VPs in three different variations: (1) patients showing a friendly behavior, (2) patients showing a disruptive behavior and (3) a version without a patient story. For easy VPs, we did not see a significant difference in diagnostic accuracy. For difficult VPs, the diagnostic accuracy was significantly higher for participants who worked on the friendly VPs compared to the other two groups. Independent from VP difficulty, participants identified significantly more problems and tests for disruptive than for friendly VPs; time on task was comparable for these two groups. The extrinsic motivation of participants working on the VPs without a patient story was significantly lower than for the students working on the friendly VPs. Our results indicate that the measured VP difficulty has a higher influence on the clinical reasoning process and diagnostic accuracy than the variations in the narratives.

Combined diagnostic performance of coronary computed tomography angiography and computed tomography derived fractional flow reserve for the evaluation of myocardial ischemia: A meta-analysis.

PubMed

Tan, Xiao Wei; Zheng, Qishi; Shi, Luming; Gao, Fei; Allen, John Carson; Coenen, Adriaan; Baumann, Stefan; Schoepf, U Joseph; Kassab, Ghassan S; Lim, Soo Teik; Wong, Aaron Sung Lung; Tan, Jack Wei Chieh; Yeo, Khung Keong; Chin, Chee Tang; Ho, Kay Woon; Tan, Swee Yaw; Chua, Terrance Siang Jin; Chan, Edwin Shih Yen; Tan, Ru San; Zhong, Liang

2017-06-01

To evaluate the combined diagnostic accuracy of coronary computed tomography angiography (CCTA) and computed tomography derived fractional flow reserve (FFRct) in patients with suspected or known coronary artery disease (CAD). PubMed, The Cochrane library, Embase and OpenGray were searched to identify studies comparing diagnostic accuracy of CCTA and FFRct. Diagnostic test measurements of FFRct were either extracted directly from the published papers or calculated from provided information. Bivariate models were conducted to synthesize the diagnostic performance of combined CCTA and FFRct at both "per-vessel" and "per-patient" levels. 7 articles were included for analysis. The combined diagnostic outcomes from "both positive" strategy, i.e. a subject was considered as "positive" only when both CCTA and FFRct were "positive", demonstrated relative high specificity (per-vessel: 0.91; per-patient: 0.81), high positive likelihood ratio (LR+, per-vessel: 7.93; per-patient: 4.26), high negative likelihood ratio (LR-, per-vessel: 0.30; per patient: 0.24) and high accuracy (per-vessel: 0.91; per-patient: 0.81) while "either positive" strategy, i.e. a subject was considered as "positive" when either CCTA or FFRct was "positive", demonstrated relative high sensitivity (per-vessel: 0.97; per-patient: 0.98), low LR+ (per-vessel: 1.50; per-patient: 1.17), low LR- (per-vessel: 0.07; per-patient: 0.09) and low accuracy (per-vessel: 0.57; per-patient: 0.54). "Both positive" strategy showed better diagnostic performance to rule in patients with non-significant stenosis compared to "either positive" strategy, as it efficiently reduces the proportion of testing false positive subjects. Copyright © 2017 Elsevier B.V. All rights reserved.

Photoplethysmography using a smartphone application for assessment of ulnar artery patency: a randomized clinical trial

PubMed Central

Di Santo, Pietro; Harnett, David T.; Simard, Trevor; Ramirez, F. Daniel; Pourdjabbar, Ali; Yousef, Altayyeb; Moreland, Robert; Bernick, Jordan; Wells, George; Dick, Alexander; Le May, Michel; Labinaz, Marino; So, Derek; Motazedian, Pouya; Jung, Richard G.; Chandrasekhar, Jaya; Mehran, Roxana; Chong, Aun-Yeong

2018-01-01

BACKGROUND: Radial artery access is commonly performed for coronary angiography and invasive hemodynamic monitoring. Despite limitations in diagnostic accuracy, the modified Allen test (manual occlusion of radial and ulnar arteries followed by release of the latter and assessment of palmar blush) is used routinely to evaluate the collateral circulation to the hand and, therefore, to determine patient eligibility for radial artery access. We sought to evaluate whether a smartphone application may provide a superior alternative to the modified Allen test. METHODS: We compared the modified Allen test with a smartphone heart rate–monitoring application (photoplethysmography readings detected using a smartphone camera lens placed on the patient’s index finger) in patients undergoing a planned cardiac catheterization. Test order was randomly assigned in a 1:1 fashion. All patients then underwent conventional plethysmography of the index finger, followed by Doppler ultrasonography of the radial and ulnar arteries (the diagnostic standard). The primary outcome was diagnostic accuracy of the heart rate–monitoring application. RESULTS: Among 438 patients who were included in the study, we found that the heart rate–monitoring application had a superior diagnostic accuracy compared with the modified Allen test (91.8% v. 81.7%, p = 0.002), attributable to its greater specificity (93.0% v. 82.8%, p = 0.001). We also found that this application had greater diagnostic accuracy for assessment of radial or ulnar artery patency in the ipsilateral and contralateral wrist (94.0% v. 84.0%, p < 0.001). INTERPRETATION: A smartphone application used at the bedside was diagnostically superior to traditional physical examination for confirming ulnar patency before radial artery access. This study highlights the potential for smartphone-based diagnostics to aid in clinical decision-making at the patient’s bedside. Trial registration: Clinicaltrials.gov, no. NCT02519491. PMID:29615421

A Comparative Study on Diagnostic Accuracy of Colour Coded Digital Images, Direct Digital Images and Conventional Radiographs for Periapical Lesions – An In Vitro Study

PubMed Central

Mubeen; K.R., Vijayalakshmi; Bhuyan, Sanat Kumar; Panigrahi, Rajat G; Priyadarshini, Smita R; Misra, Satyaranjan; Singh, Chandravir

2014-01-01

Objectives: The identification and radiographic interpretation of periapical bone lesions is important for accurate diagnosis and treatment. The present study was undertaken to study the feasibility and diagnostic accuracy of colour coded digital radiographs in terms of presence and size of lesion and to compare the diagnostic accuracy of colour coded digital images with direct digital images and conventional radiographs for assessing periapical lesions. Materials and Methods: Sixty human dry cadaver hemimandibles were obtained and periapical lesions were created in first and second premolar teeth at the junction of cancellous and cortical bone using a micromotor handpiece and carbide burs of sizes 2, 4 and 6. After each successive use of round burs, a conventional, RVG and colour coded image was taken for each specimen. All the images were evaluated by three observers. The diagnostic accuracy for each bur and image mode was calculated statistically. Results: Our results showed good interobserver (kappa > 0.61) agreement for the different radiographic techniques and for the different bur sizes. Conventional Radiography outperformed Digital Radiography in diagnosing periapical lesions made with Size two bur. Both were equally diagnostic for lesions made with larger bur sizes. Colour coding method was least accurate among all the techniques. Conclusion: Conventional radiography traditionally forms the backbone in the diagnosis, treatment planning and follow-up of periapical lesions. Direct digital imaging is an efficient technique, in diagnostic sense. Colour coding of digital radiography was feasible but less accurate however, this imaging technique, like any other, needs to be studied continuously with the emphasis on safety of patients and diagnostic quality of images. PMID:25584318

Photoplethysmography using a smartphone application for assessment of ulnar artery patency: a randomized clinical trial.

PubMed

Di Santo, Pietro; Harnett, David T; Simard, Trevor; Ramirez, F Daniel; Pourdjabbar, Ali; Yousef, Altayyeb; Moreland, Robert; Bernick, Jordan; Wells, George; Dick, Alexander; Le May, Michel; Labinaz, Marino; So, Derek; Motazedian, Pouya; Jung, Richard G; Chandrasekhar, Jaya; Mehran, Roxana; Chong, Aun-Yeong; Hibbert, Benjamin

2018-04-03

Radial artery access is commonly performed for coronary angiography and invasive hemodynamic monitoring. Despite limitations in diagnostic accuracy, the modified Allen test (manual occlusion of radial and ulnar arteries followed by release of the latter and assessment of palmar blush) is used routinely to evaluate the collateral circulation to the hand and, therefore, to determine patient eligibility for radial artery access. We sought to evaluate whether a smartphone application may provide a superior alternative to the modified Allen test. We compared the modified Allen test with a smartphone heart rate-monitoring application (photoplethysmography readings detected using a smartphone camera lens placed on the patient's index finger) in patients undergoing a planned cardiac catheterization. Test order was randomly assigned in a 1:1 fashion. All patients then underwent conventional plethysmography of the index finger, followed by Doppler ultrasonography of the radial and ulnar arteries (the diagnostic standard). The primary outcome was diagnostic accuracy of the heart rate-monitoring application. Among 438 patients who were included in the study, we found that the heart rate-monitoring application had a superior diagnostic accuracy compared with the modified Allen test (91.8% v. 81.7%, p = 0.002), attributable to its greater specificity (93.0% v. 82.8%, p = 0.001). We also found that this application had greater diagnostic accuracy for assessment of radial or ulnar artery patency in the ipsilateral and contralateral wrist (94.0% v. 84.0%, p < 0.001). A smartphone application used at the bedside was diagnostically superior to traditional physical examination for confirming ulnar patency before radial artery access. This study highlights the potential for smartphone-based diagnostics to aid in clinical decision-making at the patient's bedside. Trial registration: Clinicaltrials.gov, no. NCT02519491. © 2018 Joule Inc. or its licensors.

Health economic assessment of Gd-EOB-DTPA MRI versus ECCM-MRI and multi-detector CT for diagnosis of hepatocellular carcinoma in China

PubMed Central

He, Xiaoning; Holtorf, Anke-Peggy; Rinde, Harald; Xie, Shuangshuang; Shen, Wen; Hou, Jiancun; Li, Xuehua; Li, Ziping; Lai, Jiaming; Wang, Yuting; Zhang, Lin; Wang, Jian; Li, Xuesong; Ma, Kuansheng; Ye, Feng; Ouyang, Han; Zhao, Hong

2018-01-01

Limited data exists in China on the comparative cost of gadolinium ethoxybenzyl diethylenetriamine magnetic resonance imaging (Gd-EOB-DTPA-MRI) with other imaging techniques. This study compared the total cost of Gd-EOB-DTPA-MRI with multidetector computed tomography (MDCT) and extracellular contrast media–enhanced MRI (ECCM-MRI) as initial imaging procedures in patients with suspected hepatocellular carcinoma (HCC). We developed a decision-tree model on the basis of the Chinese clinical guidelines for HCC, which was validated by clinical experts from China. The model compared the diagnostic accuracy and costs of alternative initial imaging procedures. Compared with MDCT and ECCM-MRI, Gd-EOB-DTPA-MRI imaging was associated with higher rates of diagnostic accuracy, i.e. higher proportions of true positives (TP) and true negatives (TN) with lower false positives (FP). Total diagnosis and treatment cost per patient after the initial Gd-EOB-DTPA-MRI evaluation was similar to MDCT (¥30,360 vs. ¥30,803) and lower than that reported with ECCM-MRI (¥30,360 vs. ¥31,465). Lower treatment cost after initial Gd-EOB-DTPA-MRI was driven by reduced utilization of confirmatory diagnostic procedures and unnecessary treatments. The findings reported that Gd-EOB-DTPA-MRI offered higher diagnostic accuracy compared with MDCT and ECCM-MRI at a comparable cost, which indicates Gd-EOB-DTPA-MRI could be the preferred initial imaging procedure for the diagnosis of HCC in China. PMID:29324837

Power calculation for comparing diagnostic accuracies in a multi-reader, multi-test design.

PubMed

Kim, Eunhee; Zhang, Zheng; Wang, Youdan; Zeng, Donglin

2014-12-01

Receiver operating characteristic (ROC) analysis is widely used to evaluate the performance of diagnostic tests with continuous or ordinal responses. A popular study design for assessing the accuracy of diagnostic tests involves multiple readers interpreting multiple diagnostic test results, called the multi-reader, multi-test design. Although several different approaches to analyzing data from this design exist, few methods have discussed the sample size and power issues. In this article, we develop a power formula to compare the correlated areas under the ROC curves (AUC) in a multi-reader, multi-test design. We present a nonparametric approach to estimate and compare the correlated AUCs by extending DeLong et al.'s (1988, Biometrics 44, 837-845) approach. A power formula is derived based on the asymptotic distribution of the nonparametric AUCs. Simulation studies are conducted to demonstrate the performance of the proposed power formula and an example is provided to illustrate the proposed procedure. © 2014, The International Biometric Society.

Diagnostic value of tendon thickness and structure in the sonographic diagnosis of supraspinatus tendinopathy: room for a two-step approach.

PubMed

Arend, Carlos Frederico; Arend, Ana Amalia; da Silva, Tiago Rodrigues

2014-06-01

The aim of our study was to systematically compare different methodologies to establish an evidence-based approach based on tendon thickness and structure for sonographic diagnosis of supraspinatus tendinopathy when compared to MRI. US was obtained from 164 symptomatic patients with supraspinatus tendinopathy detected at MRI and 42 asymptomatic controls with normal MRI. Diagnostic yield was calculated for either maximal supraspinatus tendon thickness (MSTT) and tendon structure as isolated criteria and using different combinations of parallel and sequential testing at US. Chi-squared tests were performed to assess sensitivity, specificity, and accuracy of different diagnostic approaches. Mean MSTT was 6.68 mm in symptomatic patients and 5.61 mm in asymptomatic controls (P<.05). When used as an isolated criterion, MSTT>6.0mm provided best results for accuracy (93.7%) when compared to other measurements of tendon thickness. Also as an isolated criterion, abnormal tendon structure (ATS) yielded 93.2% accuracy for diagnosis. The best overall yield was obtained by both parallel and sequential testing using either MSTT>6.0mm or ATS as diagnostic criteria at no particular order, which provided 99.0% accuracy, 100% sensitivity, and 95.2% specificity. Among these parallel and sequential tests that provided best overall yield, additional analysis revealed that sequential testing first evaluating tendon structure required assessment of 258 criteria (vs. 261 for sequential testing first evaluating tendon thickness and 412 for parallel testing) and demanded a mean of 16.1s to assess diagnostic criteria and reach the diagnosis (vs. 43.3s for sequential testing first evaluating tendon thickness and 47.4s for parallel testing). We found that using either MSTT>6.0mm or ATS as diagnostic criteria for both parallel and sequential testing provides the best overall yield for sonographic diagnosis of supraspinatus tendinopathy when compared to MRI. Among these strategies, a two-step sequential approach first assessing tendon structure was advantageous because it required a lower number of criteria to be assessed and demanded less time to assess diagnostic criteria and reach the diagnosis. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Head-to-head comparison of adaptive statistical and model-based iterative reconstruction algorithms for submillisievert coronary CT angiography.

PubMed

Benz, Dominik C; Fuchs, Tobias A; Gräni, Christoph; Studer Bruengger, Annina A; Clerc, Olivier F; Mikulicic, Fran; Messerli, Michael; Stehli, Julia; Possner, Mathias; Pazhenkottil, Aju P; Gaemperli, Oliver; Kaufmann, Philipp A; Buechel, Ronny R

2018-02-01

Iterative reconstruction (IR) algorithms allow for a significant reduction in radiation dose of coronary computed tomography angiography (CCTA). We performed a head-to-head comparison of adaptive statistical IR (ASiR) and model-based IR (MBIR) algorithms to assess their impact on quantitative image parameters and diagnostic accuracy for submillisievert CCTA. CCTA datasets of 91 patients were reconstructed using filtered back projection (FBP), increasing contributions of ASiR (20, 40, 60, 80, and 100%), and MBIR. Signal and noise were measured in the aortic root to calculate signal-to-noise ratio (SNR). In a subgroup of 36 patients, diagnostic accuracy of ASiR 40%, ASiR 100%, and MBIR for diagnosis of coronary artery disease (CAD) was compared with invasive coronary angiography. Median radiation dose was 0.21 mSv for CCTA. While increasing levels of ASiR gradually reduced image noise compared with FBP (up to - 48%, P < 0.001), MBIR provided largest noise reduction (-79% compared with FBP) outperforming ASiR (-59% compared with ASiR 100%; P < 0.001). Increased noise and lower SNR with ASiR 40% and ASiR 100% resulted in substantially lower diagnostic accuracy to detect CAD as diagnosed by invasive coronary angiography compared with MBIR: sensitivity and specificity were 100 and 37%, 100 and 57%, and 100 and 74% for ASiR 40%, ASiR 100%, and MBIR, respectively. MBIR offers substantial noise reduction with increased SNR, paving the way for implementation of submillisievert CCTA protocols in clinical routine. In contrast, inferior noise reduction by ASiR negatively affects diagnostic accuracy of submillisievert CCTA for CAD detection. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2017. For permissions, please email: journals.permissions@oup.com.

Comparison of the diagnostic accuracy of a rapid immunochromatographic test and the rapid plasma reagin test for antenatal syphilis screening in Mozambique.

PubMed Central

Montoya, Pablo J.; Lukehart, Sheila A.; Brentlinger, Paula E.; Blanco, Ana J.; Floriano, Florencia; Sairosse, Josefa; Gloyd, Stephen

2006-01-01

OBJECTIVE: Programmes to control syphilis in developing countries are hampered by a lack of laboratory services, delayed diagnosis, and doubts about current screening methods. We aimed to compare the diagnostic accuracy of an immunochromatographic strip (ICS) test and the rapid plasma reagin (RPR) test with the combined gold standard (RPR, Treponema pallidum haemagglutination assay and direct immunofluorescence stain done at a reference laboratory) for the detection of syphilis in pregnancy. METHODS: We included test results from 4789 women attending their first antenatal visit at one of six health facilities in Sofala Province, central Mozambique. We compared diagnostic accuracy (sensitivity, specificity, and positive and negative predictive values) of ICS and RPR done at the health facilities and ICS performed at the reference laboratory. We also made subgroup comparisons by human immunodeficiency virus (HIV) and malaria status. FINDINGS: For active syphilis, the sensitivity of the ICS was 95.3% at the reference laboratory, and 84.1% at the health facility. The sensitivity of the RPR at the health facility was 70.7%. Specificity and positive and negative predictive values showed a similar pattern. The ICS outperformed RPR in all comparisons (P<0.001). CONCLUSION: The diagnostic accuracy of the ICS compared favourably with that of the gold standard. The use of the ICS in Mozambique and similar settings may improve the diagnosis of syphilis in health facilities, both with and without laboratories. PMID:16501726

A whole-heart motion-correction algorithm: Effects on CT image quality and diagnostic accuracy of mechanical valve prosthesis abnormalities.

PubMed

Suh, Young Joo; Kim, Young Jin; Kim, Jin Young; Chang, Suyon; Im, Dong Jin; Hong, Yoo Jin; Choi, Byoung Wook

2017-11-01

We aimed to determine the effect of a whole-heart motion-correction algorithm (new-generation snapshot freeze, NG SSF) on the image quality of cardiac computed tomography (CT) images in patients with mechanical valve prostheses compared to standard images without motion correction and to compare the diagnostic accuracy of NG SSF and standard CT image sets for the detection of prosthetic valve abnormalities. A total of 20 patients with 32 mechanical valves who underwent wide-coverage detector cardiac CT with single-heartbeat acquisition were included. The CT image quality for subvalvular (below the prosthesis) and valvular regions (valve leaflets) of mechanical valves was assessed by two observers on a four-point scale (1 = poor, 2 = fair, 3 = good, and 4 = excellent). Paired t-tests or Wilcoxon signed rank tests were used to compare image quality scores and the number of diagnostic phases (image quality score≥3) between the standard image sets and NG SSF image sets. Diagnostic performance for detection of prosthetic valve abnormalities was compared between two image sets with the final diagnosis set by re-operation or clinical findings as the standard reference. NG SSF image sets had better image quality scores than standard image sets for both valvular and subvalvular regions (P < 0.05 for both). The number of phases that were of diagnostic image quality per patient was significantly greater in the NG SSF image set than standard image set for both valvular and subvalvular regions (P < 0.0001). Diagnostic performance of NG SSF image sets for the detection of prosthetic abnormalities (20 pannus and two paravalvular leaks) was greater than that of standard image sets (P < 0.05). Application of NG SSF can improve CT image quality and diagnostic accuracy in patients with mechanical valves compared to standard images. Copyright © 2017 Society of Cardiovascular Computed Tomography. Published by Elsevier Inc. All rights reserved.

The diagnostic test accuracy of magnetic resonance imaging, magnetic resonance arthrography and computer tomography in the detection of chondral lesions of the hip.

PubMed

Smith, Toby O; Simpson, Michael; Ejindu, Vivian; Hing, Caroline B

2013-04-01

The purpose of this study was to assess the diagnostic test accuracy of magnetic resonance imaging (MRI), magnetic resonance arthrography (MRA) and multidetector arrays in CT arthrography (MDCT) for assessing chondral lesions in the hip joint. A review of the published and unpublished literature databases was performed to identify all studies reporting the diagnostic test accuracy (sensitivity/specificity) of MRI, MRA or MDCT for the assessment of adults with chondral (cartilage) lesions of the hip with surgical comparison (arthroscopic or open) as the reference test. All included studies were reviewed using the quality assessment of diagnostic accuracy studies appraisal tool. Pooled sensitivity, specificity, likelihood ratios and diagnostic odds ratios were calculated with 95 % confidence intervals using a random-effects meta-analysis for MRI, MRA and MDCT imaging. Eighteen studies satisfied the eligibility criteria. These included 648 hips from 637 patients. MRI indicated a pooled sensitivity of 0.59 (95 % CI: 0.49-0.70) and specificity of 0.94 (95 % CI: 0.90-0.97), and MRA sensitivity and specificity values were 0.62 (95 % CI: 0.57-0.66) and 0.86 (95 % CI: 0.83-0.89), respectively. The diagnostic test accuracy for the detection of hip joint cartilage lesions is currently superior for MRI compared with MRA. There were insufficient data to perform meta-analysis for MDCT or CTA protocols. Based on the current limited diagnostic test accuracy of the use of magnetic resonance or CT, arthroscopy remains the most accurate method of assessing chondral lesions in the hip joint.

Diagnostic Accuracy Assessment of Sensititre and Agar Disk Diffusion for Determining Antimicrobial Resistance Profiles of Bovine Clinical Mastitis Pathogens▿

PubMed Central

Saini, V.; Riekerink, R. G. M. Olde; McClure, J. T.; Barkema, H. W.

2011-01-01

Determining the accuracy and precision of a measuring instrument is pertinent in antimicrobial susceptibility testing. This study was conducted to predict the diagnostic accuracy of the Sensititre MIC mastitis panel (Sensititre) and agar disk diffusion (ADD) method with reference to the manual broth microdilution test method for antimicrobial resistance profiling of Escherichia coli (n = 156), Staphylococcus aureus (n = 154), streptococcal (n = 116), and enterococcal (n = 31) bovine clinical mastitis isolates. The activities of ampicillin, ceftiofur, cephalothin, erythromycin, oxacillin, penicillin, the penicillin-novobiocin combination, pirlimycin, and tetracycline were tested against the isolates. Diagnostic accuracy was determined by estimating the area under the receiver operating characteristic curve; intertest essential and categorical agreements were determined as well. Sensititre and the ADD method demonstrated moderate to highly accurate (71 to 99%) and moderate to perfect (71 to 100%) predictive accuracies for 74 and 76% of the isolate-antimicrobial MIC combinations, respectively. However, the diagnostic accuracy was low for S. aureus-ceftiofur/oxacillin combinations and other streptococcus-ampicillin combinations by either testing method. Essential agreement between Sensititre automatic MIC readings and MIC readings obtained by the broth microdilution test method was 87%. Essential agreement between Sensititre automatic and manual MIC reading methods was 97%. Furthermore, the ADD test method and Sensititre MIC method exhibited 92 and 91% categorical agreement (sensitive, intermediate, resistant) of results, respectively, compared with the reference method. However, both methods demonstrated lower agreement for E. coli-ampicillin/cephalothin combinations than for Gram-positive isolates. In conclusion, the Sensititre and ADD methods had moderate to high diagnostic accuracy and very good essential and categorical agreement for most udder pathogen-antimicrobial combinations and can be readily employed in veterinary diagnostic laboratories. PMID:21270215

Diagnostic accuracy of language sample measures with Persian-speaking preschool children.

PubMed

Kazemi, Yalda; Klee, Thomas; Stringer, Helen

2015-04-01

This study examined the diagnostic accuracy of selected language sample measures (LSMs) with Persian-speaking children. A pre-accuracy study followed by phase I and II studies are reported. Twenty-four Persian-speaking children, aged 42 to 54 months, with primary language impairment (PLI) were compared to 27 age-matched children without PLI on a set of measures derived from play-based, conversational language samples. Results showed that correlations between age and LSMs were not statistically significant in either group of children. However, a majority of LSMs differentiated children with and without PLI at the group level (phase I), while three of the measures exhibited good diagnostic accuracy at the level of the individual (phase II). We conclude that general LSMs are promising for distinguishing between children with and without PLI. Persian-specific measures are mainly helpful in identifying children without language impairment while their ability to identify children with PLI is poor.

Squash preparation: A reliable diagnostic tool in the intraoperative diagnosis of central nervous system tumors

PubMed Central

Mitra, Sumit; Kumar, Mohan; Sharma, Vivek; Mukhopadhyay, Debasis

2010-01-01

Background: Intraoperative cytology is an important diagnostic modality improving on the accuracy of the frozen sections. It has shown to play an important role especially in the intraoperative diagnosis of central nervous system tumors. Aim: To study the diagnostic accuracy of squash preparation and frozen section (FS) in the intraoperative diagnosis of central nervous system (CNS) tumors. Materials and Methods: This prospective study of 114 patients with CNS tumors was conducted over a period of 18 months (September 2004 to February 2006). The cytological preparations were stained by the quick Papanicolaou method. The squash interpretation and FS diagnosis were later compared with the paraffin section diagnosis. Results: Of the 114 patients, cytological diagnosis was offered in 96 cases. Eighteen nonneoplastic or noncontributory cases were excluded. Using hematoxylin and eosin-stained histopathology sections as the gold standard, the diagnostic accuracy of cytology was 88.5% (85/96) and the accuracy on FS diagnosis was 90.6% (87/96). Among these cases, gliomas formed the largest category of tumors (55.2%). The cytological accuracy in this group was 84.9% (45/53) and the comparative FS figure was 86.8% (46/53). In cases where the smear and the FS diagnosis did not match, the latter opinion was offered. Conclusions: Squash preparation is a reliable, rapid and easy method and can be used as a complement to FS in the intraoperative diagnosis of CNS tumors. PMID:21187881

SLOWLY REPEATED EVOKED PAIN (SREP) AS A MARKER OF CENTRAL SENSITIZATION IN FIBROMYALGIA: DIAGNOSTIC ACCURACY AND RELIABILITY IN COMPARISON WITH TEMPORAL SUMMATION OF PAIN.

PubMed

de la Coba, Pablo; Bruehl, Stephen; Gálvez-Sánchez, Carmen María; Reyes Del Paso, Gustavo A

2018-05-01

This study examined the diagnostic accuracy and test-retest reliability of a novel dynamic evoked pain protocol (slowly repeated evoked pain; SREP) compared to temporal summation of pain (TSP), a standard index of central sensitization. Thirty-five fibromyalgia (FM) and 30 rheumatoid arthritis (RA) patients completed, in pseudorandomized order, a standard mechanical TSP protocol (10 stimuli of 1s duration at the thenar eminence using a 300g monofilament with 1s interstimulus interval) and the SREP protocol (9 suprathreshold pressure stimuli of 5s duration applied to the fingernail with a 30s interstimulus interval). In order to evaluate reliability for both protocols, they were repeated in a second session 4-7 days later. Evidence for significant pain sensitization over trials (increasing pain intensity ratings) was observed for SREP in FM (p<.001) but not in RA (p=.35), whereas significant sensitization was observed in both diagnostic groups for the TSP protocol (p's<.008). Compared to TSP, SREP demonstrated higher overall diagnostic accuracy (87.7% vs. 64.6%), greater sensitivity (0.89 vs. 0.57), and greater specificity (0.87 vs. 0.73) in discriminating between FM and RA patients. Test-retest reliability of SREP sensitization was good in FM (ICCs: 0.80), and moderate in RA (ICC: 0.68). SREP seems to be a dynamic evoked pain index tapping into pain sensitization that allows for greater diagnostic accuracy in identifying FM patients compared to a standard TSP protocol. Further research is needed to study mechanisms underlying SREP and the potential utility of adding SREP to standard pain evaluation protocols.

Diagnostic relevance of high field MRI in clinical neuroradiology: the advantages and challenges of driving a sports car.

PubMed

Wattjes, Mike P; Barkhof, Frederik

2012-11-01

High field MRI operating at 3 T is increasingly being used in the field of neuroradiology on the grounds that higher magnetic field strength should theoretically lead to a higher diagnostic accuracy in the diagnosis of several disease entities. This Editorial discusses the exhaustive review by Wardlaw and colleagues of research comparing 3 T MRI with 1.5 T MRI in the field of neuroradiology. Interestingly, the authors found no convincing evidence of improved image quality, diagnostic accuracy, or reduced total examination times using 3 T MRI instead of 1.5 T MRI. These findings are highly relevant since a new generation of high field MRI systems operating at 7 T has recently been introduced. • Higher magnetic field strengths do not necessarily lead to a better diagnostic accuracy. • Disadvantages of high field MR systems have to be considered in clinical practice. • Higher field strengths are needed for functional imaging, spectroscopy, etc. • Disappointingly there are few direct comparisons of 1.5 and 3 T MRI. • Whether the next high field MR generation (7 T) will improve diagnostic accuracy has to be investigated.

Contextual information influences diagnosis accuracy and decision making in simulated emergency medicine emergencies.

PubMed

McRobert, Allistair Paul; Causer, Joe; Vassiliadis, John; Watterson, Leonie; Kwan, James; Williams, Mark A

2013-06-01

It is well documented that adaptations in cognitive processes with increasing skill levels support decision making in multiple domains. We examined skill-based differences in cognitive processes in emergency medicine physicians, and whether performance was significantly influenced by the removal of contextual information related to a patient's medical history. Skilled (n=9) and less skilled (n=9) emergency medicine physicians responded to high-fidelity simulated scenarios under high- and low-context information conditions. Skilled physicians demonstrated higher diagnostic accuracy irrespective of condition, and were less affected by the removal of context-specific information compared with less skilled physicians. The skilled physicians generated more options, and selected better quality options during diagnostic reasoning compared with less skilled counterparts. These cognitive processes were active irrespective of the level of context-specific information presented, although high-context information enhanced understanding of the patients' symptoms resulting in higher diagnostic accuracy. Our findings have implications for scenario design and the manipulation of contextual information during simulation training.

Should learners reason one step at a time? A randomised trial of two diagnostic scheme designs.

PubMed

Blissett, Sarah; Morrison, Deric; McCarty, David; Sibbald, Matthew

2017-04-01

Making a diagnosis can be difficult for learners as they must integrate multiple clinical variables. Diagnostic schemes can help learners with this complex task. A diagnostic scheme is an algorithm that organises possible diagnoses by assigning signs or symptoms (e.g. systolic murmur) to groups of similar diagnoses (e.g. aortic stenosis and aortic sclerosis) and provides distinguishing features to help discriminate between similar diagnoses (e.g. carotid pulse). The current literature does not identify whether scheme layouts should guide learners to reason one step at a time in a terminally branching scheme or weigh multiple variables simultaneously in a hybrid scheme. We compared diagnostic accuracy, perceptual errors and cognitive load using two scheme layouts for cardiac auscultation. Focused on the task of identifying murmurs on Harvey, a cardiopulmonary simulator, 86 internal medicine residents used two scheme layouts. The terminally branching scheme organised the information into single variable decisions. The hybrid scheme combined single variable decisions with a chart integrating multiple distinguishing features. Using a crossover design, participants completed one set of murmurs (diastolic or systolic) with either the terminally branching or the hybrid scheme. The second set of murmurs was completed with the other scheme. A repeated measures manova was performed to compare diagnostic accuracy, perceptual errors and cognitive load between the scheme layouts. There was a main effect of the scheme layout (Wilks' λ = 0.841, F 3,80 = 5.1, p = 0.003). Use of a terminally branching scheme was associated with increased diagnostic accuracy (65 versus 53%, p = 0.02), fewer perceptual errors (0.61 versus 0.98 errors, p = 0.001) and lower cognitive load (3.1 versus 3.5/7, p = 0.023). The terminally branching scheme was associated with improved diagnostic accuracy, fewer perceptual errors and lower cognitive load, suggesting that terminally branching schemes are effective for improving diagnostic accuracy. These findings can inform the design of schemes and other clinical decision aids. © 2017 John Wiley & Sons Ltd and The Association for the Study of Medical Education.

Assessing the dependence of sensitivity and specificity on prevalence in meta-analysis

PubMed Central

Li, Jialiang; Fine, Jason P.

2011-01-01

We consider modeling the dependence of sensitivity and specificity on the disease prevalence in diagnostic accuracy studies. Many meta-analyses compare test accuracy across studies and fail to incorporate the possible connection between the accuracy measures and the prevalence. We propose a Pearson type correlation coefficient and an estimating equation–based regression framework to help understand such a practical dependence. The results we derive may then be used to better interpret the results from meta-analyses. In the biomedical examples analyzed in this paper, the diagnostic accuracy of biomarkers are shown to be associated with prevalence, providing insights into the utility of these biomarkers in low- and high-prevalence populations. PMID:21525421

Diagnostic Accuracy of the Neck Tornado Test as a New Screening Test in Cervical Radiculopathy

PubMed Central

Park, Juyeon; Park, Woo Young; Hong, Seungbae; An, Jiwon; Koh, Jae Chul; Lee, Youn-Woo; Kim, Yong Chan; Choi, Jong Bum

2017-01-01

Background: The Spurling test, although a highly specific provocative test of the cervical spine in cervical radiculopathy (CR), has low to moderate sensitivity. Thus, we introduced the neck tornado test (NTT) to examine the neck and the cervical spine in CR. Objectives: The aim of this study was to introduce a new provocative test, the NTT, and compare the diagnostic accuracy with a widely accepted provocative test, the Spurling test. Design: Retrospective study. Methods: Medical records of 135 subjects with neck pain (CR, n = 67; without CR, n = 68) who had undergone cervical spine magnetic resonance imaging and been referred to the pain clinic between September 2014 and August 2015 were reviewed. Both the Spurling test and NTT were performed in all patients by expert examiners. Sensitivity, specificity, and accuracy were compared for both the Spurling test and the NTT. Results: The sensitivity of the Spurling test and the NTT was 55.22% and 85.07% (P < 0.0001); specificity, 98.53% and 86.76% (P = 0.0026); accuracy, 77.04% and 85.93% (P = 0.0423), respectively. Conclusions: The NTT is more sensitive with superior diagnostic accuracy for CR diagnosed by magnetic resonance imaging than the Spurling test. PMID:28824298

Accuracy in contouring of small and low contrast lesions: Comparison between diagnostic quality computed tomography scanner and computed tomography simulation scanner-A phantom study

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ho, Yick Wing, E-mail: mpr@hksh.com; Wong, Wing Kei Rebecca; Yu, Siu Ki

2012-01-01

To evaluate the accuracy in detection of small and low-contrast regions using a high-definition diagnostic computed tomography (CT) scanner compared with a radiotherapy CT simulation scanner. A custom-made phantom with cylindrical holes of diameters ranging from 2-9 mm was filled with 9 different concentrations of contrast solution. The phantom was scanned using a 16-slice multidetector CT simulation scanner (LightSpeed RT16, General Electric Healthcare, Milwaukee, WI) and a 64-slice high-definition diagnostic CT scanner (Discovery CT750 HD, General Electric Healthcare). The low-contrast regions of interest (ROIs) were delineated automatically upon their full width at half maximum of the CT number profile inmore » Hounsfield units on a treatment planning workstation. Two conformal indexes, CI{sub in}, and CI{sub out}, were calculated to represent the percentage errors of underestimation and overestimation in the automated contours compared with their actual sizes. Summarizing the conformal indexes of different sizes and contrast concentration, the means of CI{sub in} and CI{sub out} for the CT simulation scanner were 33.7% and 60.9%, respectively, and 10.5% and 41.5% were found for the diagnostic CT scanner. The mean differences between the 2 scanners' CI{sub in} and CI{sub out} were shown to be significant with p < 0.001. A descending trend of the index values was observed as the ROI size increases for both scanners, which indicates an improved accuracy when the ROI size increases, whereas no observable trend was found in the contouring accuracy with respect to the contrast levels in this study. Images acquired by the diagnostic CT scanner allow higher accuracy on size estimation compared with the CT simulation scanner in this study. We recommend using a diagnostic CT scanner to scan patients with small lesions (<1 cm in diameter) for radiotherapy treatment planning, especially for those pending for stereotactic radiosurgery in which accurate delineation of small-sized, low-contrast regions is important for dose calculation.« less

Diagnostic Accuracy of MRI-guided Percutaneous Transthoracic Needle Biopsy of Solitary Pulmonary Nodules

DOE Office of Scientific and Technical Information (OSTI.GOV)

Liu, Shangang, E-mail: 1198685580@qq.com; Li, Chengli, E-mail: chenglilichina@yeah.net; Yu, Xuejuan, E-mail: yuxuejuan2011@126.com

2015-04-15

ObjectiveThe purpose of our study was to evaluate the diagnostic accuracy of MRI-guided percutaneous transthoracic needle biopsy (PTNB) of solitary pulmonary nodules (SPNs).MethodsRetrospective review of 69 patients who underwent MR-guided PTNB of SPNs was performed. Each case was reviewed for complications. The final diagnosis was established by surgical pathology of the nodule or clinical and imaging follow-up. Pneumothorax rate and diagnostic accuracy were compared between two groups according to nodule diameter (≤2 vs. >2 cm) using χ{sup 2} chest and Fisher’s exact test, respectively.ResultsThe success rate of single puncture was 95.6 %. Twelve (17.4 %) patients had pneumothorax, with 1 (1.4 %) requiring chestmore » tube insertion. Mild hemoptysis occurred in 7 (7.2 %) patients. All of the sample material was sufficient for histological diagnostic evaluation. Pathological analysis of biopsy specimens showed 46 malignant, 22 benign, and 1 nondiagnostic nodule. The final diagnoses were 49 malignant nodules and 20 benign nodules basing on postoperative histopathology and clinical follow-up data. One nondiagnostic sample was excluded from calculating diagnostic performance. A sensitivity, specificity, accuracy, positive predictive value, and negative predictive value in diagnosing SPNs were 95.8, 100, 97.0, 100, and 90.9 %, respectively. Pneumothorax rate, diagnostic sensitivity, and accuracy were not significantly different between the two groups (P > 0.05).ConclusionsMRI-guided PTNB is safe, feasible, and high accurate diagnostic technique for pathologic diagnosis of pulmonary nodules.« less

Protocol for accuracy of point of care (POC) or in-office urine drug testing (immunoassay) in chronic pain patients: a prospective analysis of immunoassay and liquid chromatography tandem mass spectometry (LC/MS/MS).

PubMed

Manchikanti, Laxmaiah; Malla, Yogesh; Wargo, Bradley W; Cash, Kimberly A; Pampati, Vidyasagar; Damron, Kim S; McManus, Carla D; Brandon, Doris E

2010-01-01

Therapeutic use, overuse, abuse, and diversion of controlled substances in managing chronic non-cancer pain continues to be an issue for physicians and patients. It has been stated that physicians, along with the public and federal, state, and local government; professional associations; and pharmaceutical companies all share responsibility for preventing abuse of controlled prescription drugs. The challenge is to eliminate or significantly curtail abuse of controlled prescription drugs while still assuring the proper treatment of those patients. A number of techniques, instruments, and tools have been described to monitor controlled substance use and abuse. Thus, multiple techniques and tools available for adherence monitoring include urine drug testing in conjunction with prescription monitoring programs and other screening tests. However, urine drug testing is associated with multiple methodological flaws. Multiple authors have provided conflicting results in relation to diagnostic accuracy with differing opinions about how to monitor adherence in a non-systematic fashion. Thus far, there have not been any studies systematically assessing the diagnostic accuracy of immunoassay with laboratory testing. A diagnostic accuracy study of urine drug testing. An interventional pain management practice, a specialty referral center, a private practice setting in the United States. To compare the information obtained by point of care (POC) or in-office urine drug testing (index test) to the information found when all drugs and analytes are tested by liquid chromatography tandem mass spectroscopy (LC/MS/MS) reference test in the same urine sample. The study is designed to include 1,000 patients with chronic pain receiving controlled substances. The primary outcome measure is the diagnostic accuracy. Patients will be tested for various controlled substances, including opioids, benzodiazepines, and illicit drugs. The diagnostic accuracy study is performed utilizing the Standards for Reporting of Diagnostic Accuracy Studies (STARD) initiative which established reporting guidelines for diagnostic accuracy studies to improve the quality of reporting. The prototypical flow diagram of diagnostic accuracy study as described by STARD will be utilized. Results of diagnostic accuracy and correlation of clinical factors in relation to threshold levels, prevalence of abuse, false-positives, false-negatives, influence of other drugs, and demographic characteristics will be calculated. The limitations include lack of availability of POC testing with lower cutoff levels. This article presents a protocol for a diagnostic accuracy study of urine drug testing. The protocol also will permit correlation of various clinical factors in relation to threshold levels, prevalence of abuse, false-positives, false-negatives, influence of other drugs, and demographic characteristics. NCT 01052155.

Adjusting for partial verification or workup bias in meta-analyses of diagnostic accuracy studies.

PubMed

de Groot, Joris A H; Dendukuri, Nandini; Janssen, Kristel J M; Reitsma, Johannes B; Brophy, James; Joseph, Lawrence; Bossuyt, Patrick M M; Moons, Karel G M

2012-04-15

A key requirement in the design of diagnostic accuracy studies is that all study participants receive both the test under evaluation and the reference standard test. For a variety of practical and ethical reasons, sometimes only a proportion of patients receive the reference standard, which can bias the accuracy estimates. Numerous methods have been described for correcting this partial verification bias or workup bias in individual studies. In this article, the authors describe a Bayesian method for obtaining adjusted results from a diagnostic meta-analysis when partial verification or workup bias is present in a subset of the primary studies. The method corrects for verification bias without having to exclude primary studies with verification bias, thus preserving the main advantages of a meta-analysis: increased precision and better generalizability. The results of this method are compared with the existing methods for dealing with verification bias in diagnostic meta-analyses. For illustration, the authors use empirical data from a systematic review of studies of the accuracy of the immunohistochemistry test for diagnosis of human epidermal growth factor receptor 2 status in breast cancer patients.

Impact of history of heart failure on diagnostic and prognostic value of BNP: results from the B-type Natriuretic Peptide for Acute Shortness of Breath Evaluation (BASEL) study.

PubMed

Boldanova, Tujana; Noveanu, Markus; Breidthardt, Tobias; Potocki, Mihael; Reichlin, Tobias; Taegtmeyer, Anne; Christ, Michael; Laule, Kirsten; Stelzig, Claudia; Mueller, Christian

2010-07-23

This study aimed to examine the influence of history of heart failure (HF) on circulating levels, diagnostic accuracy and prognostic value of B-type natriuretic peptide (BNP) in patients presenting with all cause dyspnea at the emergency department. BNP has been shown to be very helpful in diagnosis and prognosis of HF. Due to chronically elevated cardiac filling pressures, patients with a history of HF might have higher BNP levels and therefore diagnostic and prognostic properties of BNP may be affected. We analyzed circulating levels, diagnostic accuracy and prognostic value of BNP in 388 patients without a previous history of HF and compared these to data to 64 patients with a history of HF included in the B-type Natriuretic Peptide for Acute Shortness of Breath Evaluation (BASEL) Study. Baseline BNP levels were higher in patients with a history of HF (median 814 pg/ml [353-1300 pg/ml] vs. 216 pg/ml [45-801 pg/ml], p<0.001). Diagnostic accuracy of BNP to identify HF was comparable in patients with (AUC=0.804; 95% CI 0.628-0.980) and in patients without history of HF (AUC=0.883; 95% CI 0.848-0.919, p=0.389). Prognostic ability of BNP to predict one-year mortality was lower in overall patients with history of HF (AUC=0.458; 95%CI 0.294-0.622) compared to patients without history of HF (AUC=0.710; 95% CI 0.653-0.768, p<0.05). In patients with history of HF, BNP levels retain diagnostic accuracy. Ability to predict one-year mortality was decreased in unselected patients, but not in patients with acute HF-induced dyspnea. Copyright (c) 2009 Elsevier Ireland Ltd. All rights reserved.

Comparison of digital tomosynthesis and chest radiography for the detection of pulmonary nodules: systematic review and meta-analysis.

PubMed

Kim, Jun H; Lee, Kyung H; Kim, Kyoung-Tae; Kim, Hyun J; Ahn, Hyeong S; Kim, Yeo J; Lee, Ha Y; Jeon, Yong S

2016-12-01

To compare the diagnostic accuracy of digital tomosynthesis (DTS) with that of chest radiography for the detection of pulmonary nodules by meta-analysis. A systematic literature search was performed to identify relevant original studies from 1 January 1 1976 to 31 August 31 2016. The quality of included studies was assessed by quality assessment of diagnostic accuracy studies-2. Per-patient data were used to calculate the sensitivity and specificity and per-lesion data were used to calculate the detection rate. Summary receiver-operating characteristic curves were drawn for pulmonary nodule detection. 16 studies met the inclusion criteria. 1017 patients on a per-patient basis and 2159 lesions on a per-lesion basis from 16 eligible studies were evaluated. The pooled patient-based sensitivity of DTS was 0.85 [95% confidence interval (CI) 0.83-0.88] and the specificity was 0.95 (0.93-0.96). The pooled sensitivity and specificity of chest radiography were 0.47 (0.44-0.51) and 0.37 (0.34-0.40), respectively. The per-lesion detection rate was 2.90 (95% CI 2.63-3.19). DTS has higher diagnostic accuracy than chest radiography for detection of pulmonary nodules. Chest radiography has low sensitivity but similar specificity, comparable with that of DTS. Advances in knowledge: DTS has higher diagnostic accuracy than chest radiography for the detection of pulmonary nodules.

Gender differences in the diagnostic accuracy of SPECT myocardial perfusion imaging: a bivariate meta-analysis.

PubMed

Iskandar, Aline; Limone, Brendan; Parker, Matthew W; Perugini, Andrew; Kim, Hyejin; Jones, Charles; Calamari, Brian; Coleman, Craig I; Heller, Gary V

2013-02-01

It remains controversial whether the diagnostic accuracy of single-photon emission computed tomography myocardial perfusion imaging (SPECT MPI) is different in men as compared to women. We performed a meta-analysis to investigate gender differences of SPECT MPI for the diagnosis of CAD (≥50% stenosis). Two investigators independently performed a systematic review of the MEDLINE and EMBASE databases from inception through January 2012 for English-language studies determining the diagnostic accuracy of SPECT MPI. We included prospective studies that compared SPECT MPI with conventional coronary angiography which provided sufficient data to calculate gender-specific true and false positives and negatives. Data from studies evaluating <20 patients of one gender were excluded. Bivariate meta-analysis was used to create summary receiver operating curves. Twenty-six studies met inclusion criteria, representing 1,148 women and 1,142 men. Bivariate meta-analysis yielded a mean sensitivity and specificity of 84.2% (95% confidence interval [CI] 78.7%-88.6%) and 78.7% (CI 70.0%-85.3%) for SPECT MPI in women and 89.1% (CI 84.0%-92.7%) and 71.2% (CI 60.8%-79.8%) for SPECT MPI in men. There was no significant difference in the sensitivity (P = .15) or specificity (P = .23) between male and female subjects. In a bivariate meta-analysis of the available literature, the diagnostic accuracy of SPECT MPI is similar for both men and women.

Direct comparison of PI-RADS version 2 and version 1 regarding interreader agreement and diagnostic accuracy for the detection of clinically significant prostate cancer.

PubMed

Becker, Anton S; Cornelius, Alexander; Reiner, Cäcilia S; Stocker, Daniel; Ulbrich, Erika J; Barth, Borna K; Mortezavi, Ashkan; Eberli, Daniel; Donati, Olivio F

2017-09-01

to simultaneously evaluate interreader agreement and diagnostic accuracy in the of PI-RADS v2 and compare it to v1. A total of 67 patients (median age 65.3 y, range 51.2-78.2 y; PSA 6.8μg/L, 0.2-33μg/L) undergoing MRI of the prostate and subsequent transperineal template biopsy within ≤6 months from MRI were included. Four readers from two institutions evaluated the likelihood of prostate cancer using PI-RADS v1 and v2 in two separate reading sessions ≥3 months apart. Interreader agreement was assessed for each pulse-sequence and for total PI-RADS scores using the intraclass correlation coefficient (ICC). Differences were considered significant for non-overlapping 95%-confidence intervals. Diagnostic accuracy was assessed with the area under the receiver operating characteristic curve (A Z ). A p-value <0.05 was considered statistically significant. Interreader agreement for DCE-scores was good in v2 (ICC 2 =0.70; 95% CI: 0.66-0.74) and slightly lower in v1 (ICC 1 =0.64, 0.59-0.69). Agreement for DWI scores (ICC 1 =0.77, ICC 2 =0.76) as well as final PI-RADS scores per quadrant were nearly identical (ICC 1 =ICC 2 =0.71). Diagnostic accuracy showed no significant differences (p=0.09-0.93) between v1 and v2 in any of the readers (range: A Z =0.78-0.88). PI-RADS scores show similar interreader agreement in v2 and v1 at comparable diagnostic performance. The simplification of the DCE interpretation in v2 might slightly improve agreement while not negatively affecting diagnostic performance. Copyright © 2017 Elsevier B.V. All rights reserved.

Empirical evidence of the importance of comparative studies of diagnostic test accuracy.

PubMed

Takwoingi, Yemisi; Leeflang, Mariska M G; Deeks, Jonathan J

2013-04-02

Systematic reviews that "compare" the accuracy of 2 or more tests often include different sets of studies for each test. To investigate the availability of direct comparative studies of test accuracy and to assess whether summary estimates of accuracy differ between meta-analyses of noncomparative and comparative studies. Systematic reviews in any language from the Database of Abstracts of Reviews of Effects and the Cochrane Database of Systematic Reviews from 1994 to October 2012. 1 of 2 assessors selected reviews that evaluated at least 2 tests and identified meta-analyses that included both noncomparative studies and comparative studies. 1 of 3 assessors extracted data about review and study characteristics and test performance. 248 reviews compared test accuracy; of the 6915 studies, 2113 (31%) were comparative. Thirty-six reviews (with 52 meta-analyses) had adequate studies to compare results of noncomparative and comparative studies by using a hierarchical summary receiver-operating characteristic meta-regression model for each test comparison. In 10 meta-analyses, noncomparative studies ranked tests in the opposite order of comparative studies. A total of 25 meta-analyses showed more than a 2-fold discrepancy in the relative diagnostic odds ratio between noncomparative and comparative studies. Differences in accuracy estimates between noncomparative and comparative studies were greater than expected by chance (P < 0.001). A paucity of comparative studies limited exploration of direction in bias. Evidence derived from noncomparative studies often differs from that derived from comparative studies. Robustly designed studies in which all patients receive all tests or are randomly assigned to receive one or other of the tests should be more routinely undertaken and are preferred for evidence to guide test selection. National Institute for Health Research (United Kingdom).

Comparing Magnetic Resonance Imaging and High-Resolution Dynamic Ultrasonography for Diagnosis of Plantar Plate Pathology: A Case Series.

PubMed

Donegan, Ryan J; Stauffer, Anthony; Heaslet, Michael; Poliskie, Michael

Plantar plate pathology has gained noticeable attention in recent years as an etiology of lesser metatarsophalangeal joint pain. The heightened clinical awareness has led to the need for more effective diagnostic imaging accuracy. Numerous reports have established the accuracy of both magnetic resonance imaging and ultrasonography for the diagnosis of plantar plate pathology. However, no conclusions have been made regarding which is the superior imaging modality. The present study reports a case series directly comparing high-resolution dynamic ultrasonography and magnetic resonance imaging. A multicenter retrospective comparison of magnetic resonance imaging versus high-resolution dynamic ultrasonography to evaluate plantar plate pathology with surgical confirmation was conducted. The sensitivity, specificity, and positive and negative predictive values for magnetic resonance imaging were 60%, 100%, 100%, and 33%, respectively. The overall diagnostic accuracy compared with the intraoperative findings was 66%. The sensitivity, specificity, and positive and negative predictive values for high-resolution dynamic ultrasound imaging were 100%, 100%, 100%, and 100%, respectively. The overall diagnostic accuracy compared with the intraoperative findings was 100%. The p value using Fisher's exact test for magnetic resonance imaging and high-resolution dynamic ultrasonography was p = .45, a difference that was not statistically significant. High-resolution dynamic ultrasonography had greater accuracy than magnetic resonance imaging in diagnosing lesser metatarsophalangeal joint plantar plate pathology, although the difference was not statistically significant. The present case series suggests that high-resolution dynamic ultrasonography can be considered an equally accurate imaging modality for plantar plate pathology at a potential cost savings compared with magnetic resonance imaging. Therefore, high-resolution dynamic ultrasonography warrants further investigation in a prospective study. Copyright © 2016 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

A dual tracer (68)Ga-DOTANOC PET/CT and (18)F-FDG PET/CT pilot study for detection of cardiac sarcoidosis.

PubMed

Gormsen, Lars C; Haraldsen, Ate; Kramer, Stine; Dias, Andre H; Kim, Won Yong; Borghammer, Per

2016-12-01

Cardiac sarcoidosis (CS) is a potentially fatal condition lacking a single test with acceptable diagnostic accuracy. (18)F-FDG PET/CT has emerged as a promising imaging modality, but is challenged by physiological myocardial glucose uptake. An alternative tracer, (68)Ga-DOTANOC, binds to somatostatin receptors on inflammatory cells in sarcoid granulomas. We therefore aimed to conduct a proof-of-concept study using (68)Ga-DOTANOC to diagnose CS. In addition, we compared diagnostic accuracy and inter-observer variability of (68)Ga-DOTANOC vs. (18)F-FDG PET/CT. Nineteen patients (seven female) with suspected CS were prospectively recruited and dual tracer scanned within 7 days. PET images were reviewed by four expert readers for signs of CS and compared to the reference standard (Japanese ministry of Health and Welfare CS criteria). CS was diagnosed in 3/19 patients. By consensus, 11/19 (18)F-FDG scans and 0/19 (68)Ga-DOTANOC scans were rated as inconclusive. The sensitivity of (18)F-FDG PET for diagnosing CS was 33 %, specificity was 88 %, PPV was 33 %, NPV was 88 %, and diagnostic accuracy was 79 %. For (68)Ga-DOTANOC, accuracy was 100 %. Inter-observer agreement was poor for (18)F-FDG PET (Fleiss' combined kappa 0.27, NS) and significantly better for (68)Ga-DOTANOC (Fleiss' combined kappa 0.46, p = 0.001). Despite prolonged pre-scan fasting, a large proportion of (18)F-FDG PET/CT images were rated as inconclusive, resulting in low agreement among reviewers and correspondingly poor diagnostic accuracy. By contrast, (68)Ga-DOTANOC PET/CT had excellent diagnostic accuracy with the caveat that inter-observer variability was still significant. Nevertheless, (68)Ga-DOTANOC PET/CT looks very promising as an alternative CS PET tracer. Current Controlled Trials NCT01729169 .

Diagnostic Accuracy of Periapical Radiography and Cone-beam Computed Tomography in Identifying Root Canal Configuration of Human Premolars.

PubMed

Sousa, Thiago Oliveira; Haiter-Neto, Francisco; Nascimento, Eduarda Helena Leandro; Peroni, Leonardo Vieira; Freitas, Deborah Queiroz; Hassan, Bassam

2017-07-01

The aim of this study was to assess the diagnostic accuracy of periapical radiography (PR) and cone-beam computed tomographic (CBCT) imaging in the detection of the root canal configuration (RCC) of human premolars. PR and CBCT imaging of 114 extracted human premolars were evaluated by 2 oral radiologists. RCC was recorded according to Vertucci's classification. Micro-computed tomographic imaging served as the gold standard to determine RCC. Accuracy, sensitivity, specificity, and predictive values were calculated. The Friedman test compared both PR and CBCT imaging with the gold standard. CBCT imaging showed higher values for all diagnostic tests compared with PR. Accuracy was 0.55 and 0.89 for PR and CBCT imaging, respectively. There was no difference between CBCT imaging and the gold standard, whereas PR differed from both CBCT and micro-computed tomographic imaging (P < .0001). CBCT imaging was more accurate than PR for evaluating different types of RCC individually. Canal configuration types III, VII, and "other" were poorly identified on CBCT imaging with a detection accuracy of 50%, 0%, and 43%, respectively. With PR, all canal configurations except type I were poorly visible. PR presented low performance in the detection of RCC in premolars, whereas CBCT imaging showed no difference compared with the gold standard. Canals with complex configurations were less identifiable using both imaging methods, especially PR. Copyright © 2017 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

[Risk on bias assessment: (6) A Revised Tool for the Quality Assessment on Diagnostic Accuracy Studies (QUADAS-2)].

PubMed

Qu, Y J; Yang, Z R; Sun, F; Zhan, S Y

2018-04-10

This paper introduced the Revised Tool for the Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2), including the development and comparison with the original QUADAS, and illustrated the application of QUADAS-2 in a published paper related to the study on diagnostic accuracy which was included in systematic review and Meta-analysis. QUADAS-2 presented considerable improvement over the original tool. Confused items that included in QUADAS had disappeared and the quality assessment of the original study replaced by the rating of risk on bias and applicability. This was implemented through the description on the four main domains with minimal overlapping and answering the signal questions in each domain. The risk of bias and applicability with 'high','low' or 'unclear' was in line with the risk of bias assessment of intervention studies in Cochrane, so to replace the total score of quality assessment in QUADAS. Meanwhile, QUADAS-2 was also applicable to assess the diagnostic accuracy studies in which follow-up without prognosis was involved in golden standard. It was useful to assess the overall methodological quality of the study despite more time consuming than the original QUADAS. However, QUADAS-2 needs to be modified to apply in comparative studies on diagnostic accuracy and we hope the users would follow the updates and give their feedbacks on line.

Diagnostic Accuracy of MRI Versus CT for the Evaluation of Acute Appendicitis in Children and Young Adults.

PubMed

Kinner, Sonja; Pickhardt, Perry J; Riedesel, Erica L; Gill, Kara G; Robbins, Jessica B; Kitchin, Douglas R; Ziemlewicz, Timothy J; Harringa, John B; Reeder, Scott B; Repplinger, Michael D

2017-10-01

Appendicitis is frequently diagnosed in the emergency department, most commonly using CT. The purpose of this study was to compare the diagnostic accuracy of contrast-enhanced MRI with that of contrast-enhanced CT for the diagnosis of appendicitis in adolescents when interpreted by abdominal radiologists and pediatric radiologists. Our study included a prospectively enrolled cohort of 48 patients (12-20 years old) with nontraumatic abdominal pain who underwent CT and MRI. Fellowship-trained abdominal and pediatric radiologists reviewed all CT and MRI studies in randomized order, blinded to patient outcome. Likelihood for appendicitis was rated on a 5-point scale (1, definitely not appendicitis; 5, definitely appendicitis) for CT, the unenhanced portion of the MRI, and the entire contrast-enhanced MRI study. ROC curves were generated and AUC compared for each scan type for all six readers and then stratified by radiologist type. Image test characteristics, interrater reliability, and reading times were compared. Sensitivity and specificity were 85.9% (95% CI, 76.2-92.7%) and 93.8% (95% CI, 89.7-96.7%) for unenhanced MRI, 93.6% (95% CI, 85.6-97.9%) and 94.3% (95% CI, 90.2-97%) for contrast-enhanced MRI, and 93.6% (95% CI, 85.6-97.9%) and 94.3% (95% CI, 90.2-97%) for CT. No difference was found in the diagnostic accuracy or interpretation time when comparing abdominal radiologists to pediatric radiologists (CT, 3.0 min vs 2.8 min; contrast-enhanced MRI, 2.4 min vs 1.8 min; unenhanced MRI, 1.5 min vs 2.3 min). Substantial agreement between abdominal and pediatric radiologists was seen for all methods (κ = 0.72-0.83). The diagnostic accuracy of MRI to diagnose appendicitis was very similar to CT. No statistically significant difference in accuracy was observed between imaging modality or radiologist subspecialty.

Accuracy of clinical tests in the diagnosis of anterior cruciate ligament injury: a systematic review

PubMed Central

2014-01-01

Background Numerous clinical tests are used in the diagnosis of anterior cruciate ligament (ACL) injury but their accuracy is unclear. The purpose of this study is to evaluate the diagnostic accuracy of clinical tests for the diagnosis of ACL injury. Methods Study Design: Systematic review. The review protocol was registered through PROSPERO (CRD42012002069). Electronic databases (PubMed, MEDLINE, EMBASE, CINAHL) were searched up to 19th of June 2013 to identify diagnostic studies comparing the accuracy of clinical tests for ACL injury to an acceptable reference standard (arthroscopy, arthrotomy, or MRI). Risk of bias was appraised using the QUADAS-2 checklist. Index test accuracy was evaluated using a descriptive analysis of paired likelihood ratios and displayed as forest plots. Results A total of 285 full-text articles were assessed for eligibility, from which 14 studies were included in this review. Included studies were deemed to be clinically and statistically heterogeneous, so a meta-analysis was not performed. Nine clinical tests from the history (popping sound at time of injury, giving way, effusion, pain, ability to continue activity) and four from physical examination (anterior draw test, Lachman’s test, prone Lachman’s test and pivot shift test) were investigated for diagnostic accuracy. Inspection of positive and negative likelihood ratios indicated that none of the individual tests provide useful diagnostic information in a clinical setting. Most studies were at risk of bias and reported imprecise estimates of diagnostic accuracy. Conclusion Despite being widely used and accepted in clinical practice, the results of individual history items or physical tests do not meaningfully change the probability of ACL injury. In contrast combinations of tests have higher diagnostic accuracy; however the most accurate combination of clinical tests remains an area for future research. Clinical relevance Clinicians should be aware of the limitations associated with the use of clinical tests for diagnosis of ACL injury. PMID:25187877

Accuracy of clinical tests in the diagnosis of anterior cruciate ligament injury: a systematic review.

PubMed

Swain, Michael S; Henschke, Nicholas; Kamper, Steven J; Downie, Aron S; Koes, Bart W; Maher, Chris G

2014-01-01

Numerous clinical tests are used in the diagnosis of anterior cruciate ligament (ACL) injury but their accuracy is unclear. The purpose of this study is to evaluate the diagnostic accuracy of clinical tests for the diagnosis of ACL injury. Systematic review. The review protocol was registered through PROSPERO (CRD42012002069). Electronic databases (PubMed, MEDLINE, EMBASE, CINAHL) were searched up to 19th of June 2013 to identify diagnostic studies comparing the accuracy of clinical tests for ACL injury to an acceptable reference standard (arthroscopy, arthrotomy, or MRI). Risk of bias was appraised using the QUADAS-2 checklist. Index test accuracy was evaluated using a descriptive analysis of paired likelihood ratios and displayed as forest plots. A total of 285 full-text articles were assessed for eligibility, from which 14 studies were included in this review. Included studies were deemed to be clinically and statistically heterogeneous, so a meta-analysis was not performed. Nine clinical tests from the history (popping sound at time of injury, giving way, effusion, pain, ability to continue activity) and four from physical examination (anterior draw test, Lachman's test, prone Lachman's test and pivot shift test) were investigated for diagnostic accuracy. Inspection of positive and negative likelihood ratios indicated that none of the individual tests provide useful diagnostic information in a clinical setting. Most studies were at risk of bias and reported imprecise estimates of diagnostic accuracy. Despite being widely used and accepted in clinical practice, the results of individual history items or physical tests do not meaningfully change the probability of ACL injury. In contrast combinations of tests have higher diagnostic accuracy; however the most accurate combination of clinical tests remains an area for future research. Clinicians should be aware of the limitations associated with the use of clinical tests for diagnosis of ACL injury.

The Clinical Usefulness of Endoscopic Ultrasound-Guided Fine Needle Aspiration and Biopsy for Rectal and Perirectal Lesions

PubMed Central

Soh, Jae Seung; Lee, Ho-Su; Lee, Seohyun; Bae, Jungho; Lee, Hyo Jeong; Park, Sang Hyoung; Yang, Dong-Hoon; Kim, Kyung-Jo; Ye, Byong Duk; Myung, Seung-Jae; Yang, Suk-Kyun; Kim, Jin-Ho

2015-01-01

Background/Aims Endoscopic ultrasound-guided fine needle aspiration and/or biopsy (EUS-FNA/B) have been used to diagnose subepithelial tumors (SETs) and extraluminal lesions in the gastrointestinal tract. Our group previously reported the usefulness of EUS-FNA/B for rectal and perirectal lesions. This study reports our expanded experience with EUS-FNA/B for rectal and perirectal lesions in terms of diagnostic accuracy and safety. We also included our new experience with EUS-FNB using the recently introduced ProCore needle. Methods From April 2009 to March 2014, EUS-FNA/B for rectal and perirectal lesions was performed in 30 consecutive patients. We evaluated EUS-FNA/B performance by comparing histological diagnoses with final results. We also investigated factors affecting diagnostic accuracy. Results Among 10 patients with SETs, EUS-FNA/B specimen results revealed a gastrointestinal stromal tumor in 4 patients and malignant lymphoma in 1 patient. The diagnostic accuracy of EUS-FNA/B was 50% for SETs (5/10). Among 20 patients with non-SET lesions, 8 patients were diagnosed with malignant disease and 7 were diagnosed with benign disease based on both EUS-FNA/B and the final results. The diagnostic accuracy of EUS-FNA/B for non-SET lesions was 75% (15/20). The size of lesions was the only factor related to diagnostic accuracy (P=0.027). Two complications of mild fever and asymptomatic pneumoperitoneum occurred after EUS-FNA/B. Conclusions The overall diagnostic accuracy of EUS-FNA/B for rectal and perirectal lesions was 67% (20/30). EUS-FNA/B is a clinically useful method for cytological and histological diagnoses of rectal and perirectal lesions. PMID:25931998

Real-time teleophthalmology versus face-to-face consultation: A systematic review.

PubMed

Tan, Irene J; Dobson, Lucy P; Bartnik, Stephen; Muir, Josephine; Turner, Angus W

2017-08-01

Introduction Advances in imaging capabilities and the evolution of real-time teleophthalmology have the potential to provide increased coverage to areas with limited ophthalmology services. However, there is limited research assessing the diagnostic accuracy of face-to-face teleophthalmology consultation. This systematic review aims to determine if real-time teleophthalmology provides comparable accuracy to face-to-face consultation for the diagnosis of common eye health conditions. Methods A search of PubMed, Embase, Medline and Cochrane databases and manual citation review was conducted on 6 February and 7 April 2016. Included studies involved real-time telemedicine in the field of ophthalmology or optometry, and assessed diagnostic accuracy against gold-standard face-to-face consultation. The revised quality assessment of diagnostic accuracy studies (QUADAS-2) tool assessed risk of bias. Results Twelve studies were included, with participants ranging from four to 89 years old. A broad number of conditions were assessed and include corneal and retinal pathologies, strabismus, oculoplastics and post-operative review. Quality assessment identified a high or unclear risk of bias in patient selection (75%) due to an undisclosed recruitment processes. The index test showed high risk of bias in the included studies, due to the varied interpretation and conduct of real-time teleophthalmology methods. Reference standard risk was overall low (75%), as was the risk due to flow and timing (75%). Conclusion In terms of diagnostic accuracy, real-time teleophthalmology was considered superior to face-to-face consultation in one study and comparable in six studies. Store-and-forward image transmission coupled with real-time videoconferencing is a suitable alternative to overcome poor internet transmission speeds.

Diagnosis of Grave's disease with pulmonary hypertension on chest CT.

PubMed

Lee, Hwa Yeon; Yoo, Seung Min; Kim, Hye Rin; Chun, Eun Ju; White, Charles S

To evaluate the diagnostic accuracy of chest CT findings to diagnose Grave's disease in pulmonary hypertension. We retrospectively evaluated chest CT and the medical records of 13 patients with Grave's disease with (n=6) or without pulmonary hypertension (n=7) and in 17 control patients. Presence of iso-attenuation of diffusely enlarged thyroid glands compared with adjacent neck muscle on non-enhanced CT as a diagnostic clue of Grave's disease, and assessment of pulmonary hypertension on CT has high diagnostic accuracy. Chest CT has the potential to diagnose Grave's disease with pulmonary hypertension in the absence of other information. Copyright © 2017 Elsevier Inc. All rights reserved.

Diagnostic accuracy of routine blood examinations and CSF lactate level for post-neurosurgical bacterial meningitis.

PubMed

Zhang, Yang; Xiao, Xiong; Zhang, Junting; Gao, Zhixian; Ji, Nan; Zhang, Liwei

2017-06-01

To evaluate the diagnostic accuracy of routine blood examinations and Cerebrospinal Fluid (CSF) lactate level for Post-neurosurgical Bacterial Meningitis (PBM) at a large sample-size of post-neurosurgical patients. The diagnostic accuracies of routine blood examinations and CSF lactate level to distinguish between PAM and PBM were evaluated with the values of the Area Under the Curve of the Receiver Operating Characteristic (AUC -ROC ) by retrospectively analyzing the datasets of post-neurosurgical patients in the clinical information databases. The diagnostic accuracy of routine blood examinations was relatively low (AUC -ROC <0.7). The CSF lactate level achieved rather high diagnostic accuracy (AUC -ROC =0.891; CI 95%, 0.852-0.922). The variables of patient age, operation duration, surgical diagnosis and postoperative days (the interval days between the neurosurgery and examinations) were shown to affect the diagnostic accuracy of these examinations. The variables were integrated with routine blood examinations and CSF lactate level by Fisher discriminant analysis to improve their diagnostic accuracy. As a result, the diagnostic accuracy of blood examinations and CSF lactate level was significantly improved with an AUC -ROC value=0.760 (CI 95%, 0.737-0.782) and 0.921 (CI 95%, 0.887-0.948) respectively. The PBM diagnostic accuracy of routine blood examinations was relatively low, whereas the accuracy of CSF lactate level was high. Some variables that are involved in the incidence of PBM can also affect the diagnostic accuracy for PBM. Taking into account the effects of these variables significantly improves the diagnostic accuracies of routine blood examinations and CSF lactate level. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

Value of physical tests in diagnosing cervical radiculopathy: a systematic review.

PubMed

Thoomes, Erik J; van Geest, Sarita; van der Windt, Danielle A; Falla, Deborah; Verhagen, Arianne P; Koes, Bart W; Thoomes-de Graaf, Marloes; Kuijper, Barbara; Scholten-Peeters, Wendy G M; Vleggeert-Lankamp, Carmen L

2018-01-01

In clinical practice, the diagnosis of cervical radiculopathy is based on information from the patient's history, physical examination, and diagnostic imaging. Various physical tests may be performed, but their diagnostic accuracy is unknown. This study aimed to summarize and update the evidence on diagnostic performance of tests carried out during a physical examination for the diagnosis of cervical radiculopathy. A review of the accuracy of diagnostic tests was carried out. The study sample comprised diagnostic studies comparing results of tests performed during a physical examination in diagnosing cervical radiculopathy with a reference standard of imaging or surgical findings. Sensitivity, specificity, likelihood ratios are presented, together with pooled results for sensitivity and specificity. A literature search up to March 2016 was performed in CENTRAL, PubMed (MEDLINE), Embase, CINAHL, Web of Science, and Google Scholar. The methodological quality of studies was assessed using the QUADAS-2. Five diagnostic accuracy studies were identified. Only Spurling's test was evaluated in more than one study, showing high specificity ranging from 0.89 to 1.00 (95% confidence interval [CI]: 0.59-1.00); sensitivity varied from 0.38 to 0.97 (95% CI: 0.21-0.99). No studies were found that assessed the diagnostic accuracy of widely used neurological tests such as key muscle strength, tendon reflexes, and sensory impairments. There is limited evidence for accuracy of physical examination tests for the diagnosis of cervical radiculopathy. When consistent with patient history, clinicians may use a combination of Spurling's, axial traction, and an Arm Squeeze test to increase the likelihood of a cervical radiculopathy, whereas a combined results of four negative neurodynamics tests and an Arm Squeeze test could be used to rule out the disorder. Copyright © 2017 Elsevier Inc. All rights reserved.

Diagnostic Accuracy of Obstructive Airway Adult Test for Diagnosis of Obstructive Sleep Apnea.

PubMed

Gasparini, Giulio; Vicini, Claudio; De Benedetto, Michele; Salamanca, Fabrizio; Sorrenti, Giovanni; Romandini, Mario; Bosi, Marcello; Saponaro, Gianmarco; Foresta, Enrico; Laforì, Andreina; Meccariello, Giuseppe; Bianchi, Alessandro; Toraldo, Domenico Maurizio; Campanini, Aldo; Montevecchi, Filippo; Rizzotto, Grazia; Cervelli, Daniele; Moro, Alessandro; Arigliani, Michele; Gobbi, Riccardo; Pelo, Sandro

2015-01-01

The gold standard for the diagnosis of Obstructive Sleep Apnea (OSA) is polysomnography, whose access is however reduced by costs and limited availability, so that additional diagnostic tests are needed. To analyze the diagnostic accuracy of the Obstructive Airway Adult Test (OAAT) compared to polysomnography for the diagnosis of OSA in adult patients. Ninety patients affected by OSA verified with polysomnography (AHI ≥ 5) and ten healthy patients, randomly selected, were included and all were interviewed by one blind examiner with OAAT questions. The Spearman rho, evaluated to measure the correlation between OAAT and polysomnography, was 0.72 (p < 0.01). The area under the ROC curve (95% CI) was the parameter to evaluate the accuracy of the OAAT: it was 0.91 (0.81-1.00) for the diagnosis of OSA (AHI ≥ 5), 0.90 (0.82-0.98) for moderate OSA (AHI ≥ 15), and 0.84 (0.76-0.92) for severe OSA (AHI ≥ 30). The OAAT has shown a high correlation with polysomnography and also a high diagnostic accuracy for the diagnosis of OSA. It has also been shown to be able to discriminate among the different degrees of severity of OSA. Additional large studies aiming to validate this questionnaire as a screening or diagnostic test are needed.

Bayesian evaluation of clinical diagnostic test characteristics of visual observations and remote monitoring to diagnose bovine respiratory disease in beef calves.

PubMed

White, Brad J; Goehl, Dan R; Amrine, David E; Booker, Calvin; Wildman, Brian; Perrett, Tye

2016-04-01

Accurate diagnosis of bovine respiratory disease (BRD) in beef cattle is a critical facet of therapeutic programs through promotion of prompt treatment of diseased calves in concert with judicious use of antimicrobials. Despite the known inaccuracies, visual observation (VO) of clinical signs is the conventional diagnostic modality for BRD diagnosis. Objective methods of remotely monitoring cattle wellness could improve diagnostic accuracy; however, little information exists describing the accuracy of this method compared to traditional techniques. The objective of this research is to employ Bayesian methodology to elicit diagnostic characteristics of conventional VO compared to remote early disease identification (REDI) to diagnose BRD. Data from previous literature on the accuracy of VO were combined with trial data consisting of direct comparison between VO and REDI for BRD in two populations. No true gold standard diagnostic test exists for BRD; therefore, estimates of diagnostic characteristics of each test were generated using Bayesian latent class analysis. Results indicate a 90.0% probability that the sensitivity of REDI (median 81.3%; 95% probability interval [PI]: 55.5, 95.8) was higher than VO sensitivity (64.5%; PI: 57.9, 70.8). The specificity of REDI (median 92.9%; PI: 88.2, 96.9) was also higher compared to VO (median 69.1%; PI: 66.3, 71.8). The differences in sensitivity and specificity resulted in REDI exhibiting higher positive and negative predictive values in both high (41.3%) and low (2.6%) prevalence situations. This research illustrates the potential of remote cattle monitoring to augment conventional methods of BRD diagnosis resulting in more accurate identification of diseased cattle. Copyright © 2016 Elsevier B.V. All rights reserved.

A fast Monte Carlo EM algorithm for estimation in latent class model analysis with an application to assess diagnostic accuracy for cervical neoplasia in women with AGC

PubMed Central

Kang, Le; Carter, Randy; Darcy, Kathleen; Kauderer, James; Liao, Shu-Yuan

2013-01-01

In this article we use a latent class model (LCM) with prevalence modeled as a function of covariates to assess diagnostic test accuracy in situations where the true disease status is not observed, but observations on three or more conditionally independent diagnostic tests are available. A fast Monte Carlo EM (MCEM) algorithm with binary (disease) diagnostic data is implemented to estimate parameters of interest; namely, sensitivity, specificity, and prevalence of the disease as a function of covariates. To obtain standard errors for confidence interval construction of estimated parameters, the missing information principle is applied to adjust information matrix estimates. We compare the adjusted information matrix based standard error estimates with the bootstrap standard error estimates both obtained using the fast MCEM algorithm through an extensive Monte Carlo study. Simulation demonstrates that the adjusted information matrix approach estimates the standard error similarly with the bootstrap methods under certain scenarios. The bootstrap percentile intervals have satisfactory coverage probabilities. We then apply the LCM analysis to a real data set of 122 subjects from a Gynecologic Oncology Group (GOG) study of significant cervical lesion (S-CL) diagnosis in women with atypical glandular cells of undetermined significance (AGC) to compare the diagnostic accuracy of a histology-based evaluation, a CA-IX biomarker-based test and a human papillomavirus (HPV) DNA test. PMID:24163493

Diagnostic accuracy of an artificial neural network compared with statistical quantitation of myocardial perfusion images: a Japanese multicenter study.

PubMed

Nakajima, Kenichi; Kudo, Takashi; Nakata, Tomoaki; Kiso, Keisuke; Kasai, Tokuo; Taniguchi, Yasuyo; Matsuo, Shinro; Momose, Mitsuru; Nakagawa, Masayasu; Sarai, Masayoshi; Hida, Satoshi; Tanaka, Hirokazu; Yokoyama, Kunihiko; Okuda, Koichi; Edenbrandt, Lars

2017-12-01

Artificial neural networks (ANN) might help to diagnose coronary artery disease. This study aimed to determine whether the diagnostic accuracy of an ANN-based diagnostic system and conventional quantitation are comparable. The ANN was trained to classify potentially abnormal areas as true or false based on the nuclear cardiology expert interpretation of 1001 gated stress/rest 99m Tc-MIBI images at 12 hospitals. The diagnostic accuracy of the ANN was compared with 364 expert interpretations that served as the gold standard of abnormality for the validation study. Conventional summed stress/rest/difference scores (SSS/SRS/SDS) were calculated and compared with receiver operating characteristics (ROC) analysis. The ANN generated a better area under the ROC curves (AUC) than SSS (0.92 vs. 0.82, p < 0.0001), indicating better identification of stress defects. The ANN also generated a better AUC than SDS (0.90 vs. 0.75, p < 0.0001) for stress-induced ischemia. The AUC for patients with old myocardial infarction based on rest defects was 0.97 (0.91 for SRS, p = 0.0061), and that for patients with and without a history of revascularization based on stress defects was 0.94 and 0.90 (p = 0.0055 and p < 0.0001 vs. SSS, respectively). The SSS/SRS/SDS steeply increased when ANN values (probability of abnormality) were >0.80. The ANN was diagnostically accurate in various clinical settings, including that of patients with previous myocardial infarction and coronary revascularization. The ANN could help to diagnose coronary artery disease.

The Generalized Anxiety Disorder Screener (GAD-7) and the anxiety module of the Hospital and Depression Scale (HADS-A) as screening tools for generalized anxiety disorder among cancer patients.

PubMed

Esser, Peter; Hartung, Tim J; Friedrich, Michael; Johansen, Christoffer; Wittchen, Hans-Ulrich; Faller, Hermann; Koch, Uwe; Härter, Martin; Keller, Monika; Schulz, Holger; Wegscheider, Karl; Weis, Joachim; Mehnert, Anja

2018-06-01

Anxiety in cancer patients may represent a normal psychological reaction. To detect patients with pathological levels, appropriate screeners with established cut-offs are needed. Given that previous research is sparse, we investigated the diagnostic accuracy of 2 frequently used screening tools in detecting generalized anxiety disorder (GAD). We used data of a multicenter study including 2141 cancer patients. Diagnostic accuracy was investigated for the Generalized Anxiety Disorder Screener (GAD-7) and the anxiety module of the Hospital Anxiety and Depression Scale (HADS-A). GAD, assessed with the Composite International Diagnostic Interview for Oncology, served as a reference standard. Overall accuracy was measured with the area under the receiver operating characteristics curve (AUC). The AUC of the 2 screeners were statistically compared. We also calculated accuracy measures for selected cut-offs. Diagnostic accuracy could be interpreted as adequate for both screeners, with an identical AUC of .81 (95% CI: .79-.82). Consequently, the 2 screeners did not differ in their performance (P = .86). The best balance between sensitivity and specificity was found for cut-offs ≥7 (GAD-7) and ≥8 (HADS-A). The officially recommended thresholds for the GAD-7 (≥ 10) and the HADS-A (≥11) showed low sensitivities of 55% and 48%, respectively. The GAD-7 and HADS-A showed AUC of adequate diagnostic accuracy and hence are applicable for GAD screening in cancer patients. Nevertheless, the choice of optimal cut-offs should be carefully evaluated. Copyright © 2018 John Wiley & Sons, Ltd.

The Screening Accuracy of the Parent and Teacher-Reported Social Responsiveness Scale (SRS): Comparison with the 3Di and ADOS.

PubMed

Duvekot, Jorieke; van der Ende, Jan; Verhulst, Frank C; Greaves-Lord, Kirstin

2015-06-01

The screening accuracy of the parent and teacher-reported Social Responsiveness Scale (SRS) was compared with an autism spectrum disorder (ASD) classification according to (1) the Developmental, Dimensional, and Diagnostic Interview (3 Di), (2) the Autism Diagnostic Observation Schedule (ADOS), (3) both the 3 Di and ADOS, in 186 children referred to six mental health centers. The parent report showed excellent correspondence to an ASD classification according to the 3 Di and both the 3 Di and ADOS. The teacher report added significantly to the screening accuracy over and above the parent report when compared with the ADOS classification. Findings support the screening utility of the parent-reported SRS among clinically referred children and indicate that different informants may provide unique information relevant for ASD assessment.

Diagnostic performance of an automated analysis software for the diagnosis of Alzheimer’s dementia with 18F FDG PET

PubMed Central

Partovi, Sasan; Yuh, Roger; Pirozzi, Sara; Lu, Ziang; Couturier, Spencer; Grosse, Ulrich; Schluchter, Mark D; Nelson, Aaron; Jones, Robert; O’Donnell, James K; Faulhaber, Peter

2017-01-01

The objective of this study was to assess the ability of a quantitative software-aided approach to improve the diagnostic accuracy of 18F FDG PET for Alzheimer’s dementia over visual analysis alone. Twenty normal subjects (M:F-12:8; mean age 80.6 years) and twenty mild AD subjects (M:F-12:8; mean age 70.6 years) with 18F FDG PET scans were obtained from the ADNI database. Three blinded readers interpreted these PET images first using a visual qualitative approach and then using a quantitative software-aided approach. Images were classified on two five-point scales based on normal/abnormal (1-definitely normal; 5-definitely abnormal) and presence of AD (1-definitely not AD; 5-definitely AD). Diagnostic sensitivity, specificity, and accuracy for both approaches were compared based on the aforementioned scales. The sensitivity, specificity, and accuracy for the normal vs. abnormal readings of all readers combined were higher when comparing the software-aided vs. visual approach (sensitivity 0.93 vs. 0.83 P = 0.0466; specificity 0.85 vs. 0.60 P = 0.0005; accuracy 0.89 vs. 0.72 P<0.0001). The specificity and accuracy for absence vs. presence of AD of all readers combined were higher when comparing the software-aided vs. visual approach (specificity 0.90 vs. 0.70 P = 0.0008; accuracy 0.81 vs. 0.72 P = 0.0356). Sensitivities of the software-aided and visual approaches did not differ significantly (0.72 vs. 0.73 P = 0.74). The quantitative software-aided approach appears to improve the performance of 18F FDG PET for the diagnosis of mild AD. It may be helpful for experienced 18F FDG PET readers analyzing challenging cases. PMID:28123864

Diagnostic Efficiency in Digital Pathology: A Comparison of Optical Versus Digital Assessment in 510 Surgical Pathology Cases.

PubMed

Mills, Anne M; Gradecki, Sarah E; Horton, Bethany J; Blackwell, Rebecca; Moskaluk, Christopher A; Mandell, James W; Mills, Stacey E; Cathro, Helen P

2018-01-01

Prior work has shown that digital images and microscopic slides can be interpreted with comparable diagnostic accuracy. Although accuracy has been well-validated, the interpretative time for digital images has scarcely been studied and concerns about efficiency remain a major barrier to adoption. We investigated the efficiency of digital pathology when compared with glass slide interpretation in the diagnosis of surgical pathology biopsy and resection specimens. Slides were pulled from 510 surgical pathology cases from 5 organ systems (gastrointestinal, gynecologic, liver, bladder, and brain). Original diagnoses were independently confirmed by 2 validating pathologists. Diagnostic slides were scanned using the Philips IntelliSite Pathology Solution. Each case was assessed independently on digital and optical by 3 reading pathologists, with a ≥6 week washout period between modalities. Reading pathologists recorded assessment times for each modality; digital times included time to load the case. Diagnostic accuracy was determined based on whether a rendered diagnosis differed significantly from the original diagnosis. Statistical analysis was performed to assess for differences in interpretative times across modalities. All 3 reading pathologists showed comparable diagnostic accuracy across optical and digital modalities (mean major discordance rates with original diagnosis: 4.8% vs. 4.4%, respectively). Mean assessment times ranged from 1.2 to 9.1 seconds slower on digital versus optical. The slowest reader showed a significant learning effect during the course of the study so that digital assessment times decreased over time and were comparable with optical times by the end of the series. Organ site and specimen type did not significantly influence differences in interpretative times. In summary, digital image reading times compare favorably relative to glass slides across a variety of organ systems and specimen types. Mean increase in assessment time is 4 seconds/case. This time can be minimized with experience and may be further balanced by the improved ease of electronic chart access allowed by digital slide viewing, as well as quantitative assessments which can be expedited on digital images.

Diagnostic accuracy of functional, imaging and biochemical tests for patients presenting with chest pain to the emergency department: A systematic review and meta-analysis.

PubMed

Iannaccone, Mario; Gili, Sebastiano; De Filippo, Ovidio; D'Amico, Salvatore; Gagliardi, Marco; Bertaina, Maurizio; Mazzilli, Silvia; Rettegno, Sara; Bongiovanni, Federica; Gatti, Paolo; Ugo, Fabrizio; Boccuzzi, Giacomo G; Colangelo, Salvatore; Prato, Silvia; Moretti, Claudio; D'Amico, Maurizio; Noussan, Patrizia; Garbo, Roberto; Hildick-Smith, David; Gaita, Fiorenzo; D'Ascenzo, Fabrizio

2018-01-01

Non-invasive ischaemia tests and biomarkers are widely adopted to rule out acute coronary syndrome in the emergency department. Their diagnostic accuracy has yet to be precisely defined. Medline, Cochrane Library CENTRAL, EMBASE and Biomed Central were systematically screened (start date 1 September 2016, end date 1 December 2016). Prospective studies (observational or randomised controlled trial) comparing functional/imaging or biochemical tests for patients presenting with chest pain to the emergency department were included. Overall, 77 studies were included, for a total of 49,541 patients (mean age 59.9 years). Fast and six-hour highly sensitive troponin T protocols did not show significant differences in their ability to detect acute coronary syndromes, as they reported a sensitivity and specificity of 0.89 (95% confidence interval 0.79-0.94) and 0.84 (0.74-0.9) vs 0.89 (0.78-0.94) and 0.83 (0.70-0.92), respectively. The addition of copeptin to troponin increased sensitivity and reduced specificity, without improving diagnostic accuracy. The diagnostic value of non-invasive tests for patients without troponin increase was tested. Coronary computed tomography showed the highest level of diagnostic accuracy (sensitivity 0.93 (0.81-0.98) and specificity 0.90 (0.93-0.94)), along with myocardial perfusion scintigraphy (sensitivity 0.85 (0.77-0.91) and specificity 0.92 (0.83-0.96)). Stress echography was inferior to coronary computed tomography but non-inferior to myocardial perfusion scintigraphy, while exercise testing showed the lower level of diagnostic accuracy. Fast and six-hour highly sensitive troponin T protocols provide an overall similar level of diagnostic accuracy to detect acute coronary syndrome. Among the non-invasive ischaemia tests for patients without troponin increase, coronary computed tomography and myocardial perfusion scintigraphy showed the highest sensitivity and specificity.

Preferred Reporting Items for a Systematic Review and Meta-analysis of Diagnostic Test Accuracy Studies: The PRISMA-DTA Statement.

PubMed

McInnes, Matthew D F; Moher, David; Thombs, Brett D; McGrath, Trevor A; Bossuyt, Patrick M; Clifford, Tammy; Cohen, Jérémie F; Deeks, Jonathan J; Gatsonis, Constantine; Hooft, Lotty; Hunt, Harriet A; Hyde, Christopher J; Korevaar, Daniël A; Leeflang, Mariska M G; Macaskill, Petra; Reitsma, Johannes B; Rodin, Rachel; Rutjes, Anne W S; Salameh, Jean-Paul; Stevens, Adrienne; Takwoingi, Yemisi; Tonelli, Marcello; Weeks, Laura; Whiting, Penny; Willis, Brian H

2018-01-23

Systematic reviews of diagnostic test accuracy synthesize data from primary diagnostic studies that have evaluated the accuracy of 1 or more index tests against a reference standard, provide estimates of test performance, allow comparisons of the accuracy of different tests, and facilitate the identification of sources of variability in test accuracy. To develop the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) diagnostic test accuracy guideline as a stand-alone extension of the PRISMA statement. Modifications to the PRISMA statement reflect the specific requirements for reporting of systematic reviews and meta-analyses of diagnostic test accuracy studies and the abstracts for these reviews. Established standards from the Enhancing the Quality and Transparency of Health Research (EQUATOR) Network were followed for the development of the guideline. The original PRISMA statement was used as a framework on which to modify and add items. A group of 24 multidisciplinary experts used a systematic review of articles on existing reporting guidelines and methods, a 3-round Delphi process, a consensus meeting, pilot testing, and iterative refinement to develop the PRISMA diagnostic test accuracy guideline. The final version of the PRISMA diagnostic test accuracy guideline checklist was approved by the group. The systematic review (produced 64 items) and the Delphi process (provided feedback on 7 proposed items; 1 item was later split into 2 items) identified 71 potentially relevant items for consideration. The Delphi process reduced these to 60 items that were discussed at the consensus meeting. Following the meeting, pilot testing and iterative feedback were used to generate the 27-item PRISMA diagnostic test accuracy checklist. To reflect specific or optimal contemporary systematic review methods for diagnostic test accuracy, 8 of the 27 original PRISMA items were left unchanged, 17 were modified, 2 were added, and 2 were omitted. The 27-item PRISMA diagnostic test accuracy checklist provides specific guidance for reporting of systematic reviews. The PRISMA diagnostic test accuracy guideline can facilitate the transparent reporting of reviews, and may assist in the evaluation of validity and applicability, enhance replicability of reviews, and make the results from systematic reviews of diagnostic test accuracy studies more useful.

Comparison of digital tomosynthesis and chest radiography for the detection of pulmonary nodules: systematic review and meta-analysis

PubMed Central

Kim, Jun H; Lee, Kyung H; Kim, Kyoung-Tae; Ahn, Hyeong S; Kim, Yeo J; Lee, Ha Y; Jeon, Yong S

2016-01-01

Objective: To compare the diagnostic accuracy of digital tomosynthesis (DTS) with that of chest radiography for the detection of pulmonary nodules by meta-analysis. Methods: A systematic literature search was performed to identify relevant original studies from 1 January 1 1976 to 31 August 31 2016. The quality of included studies was assessed by quality assessment of diagnostic accuracy studies-2. Per-patient data were used to calculate the sensitivity and specificity and per-lesion data were used to calculate the detection rate. Summary receiver-operating characteristic curves were drawn for pulmonary nodule detection. Results: 16 studies met the inclusion criteria. 1017 patients on a per-patient basis and 2159 lesions on a per-lesion basis from 16 eligible studies were evaluated. The pooled patient-based sensitivity of DTS was 0.85 [95% confidence interval (CI) 0.83–0.88] and the specificity was 0.95 (0.93–0.96). The pooled sensitivity and specificity of chest radiography were 0.47 (0.44–0.51) and 0.37 (0.34–0.40), respectively. The per-lesion detection rate was 2.90 (95% CI 2.63–3.19). Conclusion: DTS has higher diagnostic accuracy than chest radiography for detection of pulmonary nodules. Chest radiography has low sensitivity but similar specificity, comparable with that of DTS. Advances in knowledge: DTS has higher diagnostic accuracy than chest radiography for the detection of pulmonary nodules. PMID:27759428

Diagnostic performance of semi-quantitative and quantitative stress CMR perfusion analysis: a meta-analysis.

PubMed

van Dijk, R; van Assen, M; Vliegenthart, R; de Bock, G H; van der Harst, P; Oudkerk, M

2017-11-27

Stress cardiovascular magnetic resonance (CMR) perfusion imaging is a promising modality for the evaluation of coronary artery disease (CAD) due to high spatial resolution and absence of radiation. Semi-quantitative and quantitative analysis of CMR perfusion are based on signal-intensity curves produced during the first-pass of gadolinium contrast. Multiple semi-quantitative and quantitative parameters have been introduced. Diagnostic performance of these parameters varies extensively among studies and standardized protocols are lacking. This study aims to determine the diagnostic accuracy of semi- quantitative and quantitative CMR perfusion parameters, compared to multiple reference standards. Pubmed, WebOfScience, and Embase were systematically searched using predefined criteria (3272 articles). A check for duplicates was performed (1967 articles). Eligibility and relevance of the articles was determined by two reviewers using pre-defined criteria. The primary data extraction was performed independently by two researchers with the use of a predefined template. Differences in extracted data were resolved by discussion between the two researchers. The quality of the included studies was assessed using the 'Quality Assessment of Diagnostic Accuracy Studies Tool' (QUADAS-2). True positives, false positives, true negatives, and false negatives were subtracted/calculated from the articles. The principal summary measures used to assess diagnostic accuracy were sensitivity, specificity, andarea under the receiver operating curve (AUC). Data was pooled according to analysis territory, reference standard and perfusion parameter. Twenty-two articles were eligible based on the predefined study eligibility criteria. The pooled diagnostic accuracy for segment-, territory- and patient-based analyses showed good diagnostic performance with sensitivity of 0.88, 0.82, and 0.83, specificity of 0.72, 0.83, and 0.76 and AUC of 0.90, 0.84, and 0.87, respectively. In per territory analysis our results show similar diagnostic accuracy comparing anatomical (AUC 0.86(0.83-0.89)) and functional reference standards (AUC 0.88(0.84-0.90)). Only the per territory analysis sensitivity did not show significant heterogeneity. None of the groups showed signs of publication bias. The clinical value of semi-quantitative and quantitative CMR perfusion analysis remains uncertain due to extensive inter-study heterogeneity and large differences in CMR perfusion acquisition protocols, reference standards, and methods of assessment of myocardial perfusion parameters. For wide spread implementation, standardization of CMR perfusion techniques is essential. CRD42016040176 .

STARD 2015: An Updated List of Essential Items for Reporting Diagnostic Accuracy Studies.

PubMed

Bossuyt, Patrick M; Reitsma, Johannes B; Bruns, David E; Gatsonis, Constantine A; Glasziou, Paul P; Irwig, Les; Lijmer, Jeroen G; Moher, David; Rennie, Drummond; de Vet, Henrica C W; Kressel, Herbert Y; Rifai, Nader; Golub, Robert M; Altman, Douglas G; Hooft, Lotty; Korevaar, Daniël A; Cohen, Jérémie F

2015-12-01

Incomplete reporting has been identified as a major source of avoidable waste in biomedical research. Essential information is often not provided in study reports, impeding the identification, critical appraisal, and replication of studies. To improve the quality of reporting of diagnostic accuracy studies, the Standards for Reporting of Diagnostic Accuracy Studies (STARD) statement was developed. Here we present STARD 2015, an updated list of 30 essential items that should be included in every report of a diagnostic accuracy study. This update incorporates recent evidence about sources of bias and variability in diagnostic accuracy and is intended to facilitate the use of STARD. As such, STARD 2015 may help to improve completeness and transparency in reporting of diagnostic accuracy studies.

Diagnostic accuracy of automatic normalization of CBV in glioma grading using T1- weighted DCE-MRI.

PubMed

Sahoo, Prativa; Gupta, Rakesh K; Gupta, Pradeep K; Awasthi, Ashish; Pandey, Chandra M; Gupta, Mudit; Patir, Rana; Vaishya, Sandeep; Ahlawat, Sunita; Saha, Indrajit

2017-12-01

Aim of this retrospective study was to compare diagnostic accuracy of proposed automatic normalization method to quantify the relative cerebral blood volume (rCBV) with existing contra-lateral region of interest (ROI) based CBV normalization method for glioma grading using T1-weighted dynamic contrast enhanced MRI (DCE-MRI). Sixty patients with histologically confirmed gliomas were included in this study retrospectively. CBV maps were generated using T1-weighted DCE-MRI and are normalized by contralateral ROI based method (rCBV_contra), unaffected white matter (rCBV_WM) and unaffected gray matter (rCBV_GM), the latter two of these were generated automatically. An expert radiologist with >10years of experience in DCE-MRI and a non-expert with one year experience were used independently to measure rCBVs. Cutoff values for glioma grading were decided from ROC analysis. Agreement of histology with rCBV_WM, rCBV_GM and rCBV_contra respectively was studied using Kappa statistics and intra-class correlation coefficient (ICC). The diagnostic accuracy of glioma grading using the measured rCBV_contra by expert radiologist was found to be high (sensitivity=1.00, specificity=0.96, p<0.001) compared to the non-expert user (sensitivity=0.65, specificity=0.78, p<0.001). On the other hand, both the expert and non-expert user showed similar diagnostic accuracy for automatic rCBV_WM (sensitivity=0.89, specificity=0.87, p=0.001) and rCBV_GM (sensitivity=0.81, specificity=0.78, p=0.001) measures. Further, it was also observed that, contralateral based method by expert user showed highest agreement with histological grading of tumor (kappa=0.96, agreement 98.33%, p<0.001), however; automatic normalization method showed same percentage of agreement for both expert and non-expert user. rCBV_WM showed an agreement of 88.33% (kappa=0.76,p<0.001) with histopathological grading. It was inferred from this study that, in the absence of expert user, automated normalization of CBV using the proposed method could provide better diagnostic accuracy compared to the manual contralateral based approach. Copyright © 2017 Elsevier Inc. All rights reserved.

Comparison of the Diagnostic Accuracy of DSC- and Dynamic Contrast-Enhanced MRI in the Preoperative Grading of Astrocytomas.

PubMed

Nguyen, T B; Cron, G O; Perdrizet, K; Bezzina, K; Torres, C H; Chakraborty, S; Woulfe, J; Jansen, G H; Sinclair, J; Thornhill, R E; Foottit, C; Zanette, B; Cameron, I G

2015-11-01

Dynamic contrast-enhanced MR imaging parameters can be biased by poor measurement of the vascular input function. We have compared the diagnostic accuracy of dynamic contrast-enhanced MR imaging by using a phase-derived vascular input function and "bookend" T1 measurements with DSC MR imaging for preoperative grading of astrocytomas. This prospective study included 48 patients with a new pathologic diagnosis of an astrocytoma. Preoperative MR imaging was performed at 3T, which included 2 injections of 5-mL gadobutrol for dynamic contrast-enhanced and DSC MR imaging. During dynamic contrast-enhanced MR imaging, both magnitude and phase images were acquired to estimate plasma volume obtained from phase-derived vascular input function (Vp_Φ) and volume transfer constant obtained from phase-derived vascular input function (K(trans)_Φ) as well as plasma volume obtained from magnitude-derived vascular input function (Vp_SI) and volume transfer constant obtained from magnitude-derived vascular input function (K(trans)_SI). From DSC MR imaging, corrected relative CBV was computed. Four ROIs were placed over the solid part of the tumor, and the highest value among the ROIs was recorded. A Mann-Whitney U test was used to test for difference between grades. Diagnostic accuracy was assessed by using receiver operating characteristic analysis. Vp_ Φ and K(trans)_Φ values were lower for grade II compared with grade III astrocytomas (P < .05). Vp_SI and K(trans)_SI were not significantly different between grade II and grade III astrocytomas (P = .08-0.15). Relative CBV and dynamic contrast-enhanced MR imaging parameters except for K(trans)_SI were lower for grade III compared with grade IV (P ≤ .05). In differentiating low- and high-grade astrocytomas, we found no statistically significant difference in diagnostic accuracy between relative CBV and dynamic contrast-enhanced MR imaging parameters. In the preoperative grading of astrocytomas, the diagnostic accuracy of dynamic contrast-enhanced MR imaging parameters is similar to that of relative CBV. © 2015 by American Journal of Neuroradiology.

FNA diagnostic value in patients with neck masses in two teaching hospitals in Iran.

PubMed

Saatian, Minoo; Badie, Banafsheh Moradmand; Shahriari, Sogol; Fattahi, Fahimeh; Rasoolinejad, Mehrnaz

2011-01-01

The FNA (fine needle aspiration) procedure is simple, inexpensive, available and a safe method for the diagnosis of a neck mass. FNA has numerous advantages over open surgical biopsies as an initial diagnostic tool; therefore we decided to compare the accuracy of this method with open biopsy. This retrospective as well as descriptive study comparing preoperative FNA results with existing data in the Pathology Department in Bu-Ali and Amir Alam Hospitals. Our study included 100 patients with neck masses of which 22 were thyroid masses, 31 were salivary gland masses, and 47 were other masses. Age ranged from 3 years to 80 years with the mean age of 42.6 years. There were 59 men and 41 women. The Sensitivity was 72%, Specificity 87%, PPV 85%, NPV 75% and diagnostic Accuracy 79%. In this study we had also 26% false negative and 15% false positive. FNA is a valuable diagnostic tool in the management of neck masses; also it has been used for staging and planning of treatment for the wide and metastatic malignancy. This technique reduces the need for more invasive and costly procedures. According to the high sensitivity and high accuracy in this study, FNA can be used as the first step of diagnoses test in neck masses.

Limits of the possible: diagnostic image quality in coronary angiography with third-generation dual-source CT.

PubMed

Ochs, Marco M; Siepen, Fabian Aus dem; Fritz, Thomas; Andre, Florian; Gitsioudis, Gitsios; Korosoglou, Grigorios; Seitz, Sebastian; Bogomazov, Yuriy; Schlett, Christopher L; Sokiranski, Roman; Sommer, Andre; Gückel, Friedemann; Brado, Matthias; Kauczor, Hans-Ulrich; Görich, Johannes; Friedrich, Matthias G W; Katus, Hugo A; Buss, Sebastian J

2017-07-01

The usage of coronary CT angiography (CTA) is appropriate in patients with acute or chronic chest pain; however the diagnostic accuracy may be challenged with increased Agatston score (AS), increased heart rate, arrhythmia and severe obesity. Thus, we aim to determine the potential of the recently introduced third-generation dual-source CT (DSCT) for CTA in a 'real-life' clinical setting. Two hundred and sixty-eight consecutive patients (age: 67 ± 10 years; BMI: 27 ± 5 kg/m²; 61% male) undergoing clinically indicated CTA with DSCT were included in the retrospective single-center analysis. A contrast-enhanced volume dataset was acquired in sequential (SSM) (n = 151) or helical scan mode (HSM) (n = 117). Coronary segments were classified in diagnostic or non-diagnostic image quality. A subset underwent invasive angiography to determine the diagnostic accuracy of CTA. SSM (96.8 ± 6%) and HSM (97.5 ± 8%) provided no significant differences in the overall diagnostic image quality. However, AS had significant influence on diagnostic image quality exclusively in SSM (B = 0.003; p = 0.0001), but not in HSM. Diagnostic image quality significantly decreased in SSM in patients with AS ≥2,000 (p = 0.03). SSM (sensitivity: 93.9%; specificity: 96.7%; PPV: 88.6%; NPV: 98.3%) and HSM (sensitivity: 97.4%; specificity: 94.3%; PPV: 86.0%; NPV: 99.0%) provided comparable diagnostic accuracy (p = n.s.). SSM yielded significantly lower radiation doses as compared to HSM (2.1 ± 2.0 vs. 5.1 ± 3.3 mSv; p = 0.0001) in age and BMI-matched cohorts. SSM in third-generation DSCT enables significant dose savings and provides robust diagnostic image quality in patients with AS ≤2000 independent of heart rate, heart rhythm or obesity.

The diagnostic accuracy and outcomes after coronary computed tomography angiography vs. conventional functional testing in patients with stable angina pectoris: a systematic review and meta-analysis.

PubMed

Nielsen, Lene H; Ortner, Nino; Nørgaard, Bjarne L; Achenbach, Stephan; Leipsic, Jonathon; Abdulla, Jawdat

2014-09-01

To systematically review and perform a meta-analysis of the diagnostic accuracy and post-test outcomes of conventional exercise electrocardiography (XECG) and single-photon emission computed tomography (SPECT) compared with coronary computed tomography angiography (coronary CTA) in patients suspected of stable coronary artery disease (CAD). We systematically searched for studies published from January 2002 to February 2013 examining the diagnostic accuracy (defined as at least ≥50% luminal obstruction on invasive coronary angiography) and outcomes of coronary CTA (≥16 slice) in comparison with XECG and SPECT. The search revealed 11 eligible studies (N = 1575) comparing the diagnostic accuracy and 7 studies (N = 216.603) the outcomes of coronary CTA vs. XECG or/and SPECT. The per-patient sensitivity [95% confidence interval (95% CI)] to identify significant CAD was 98% (93-99%) for coronary CTA vs. 67% (54-78%) (P < 0.001) for XECG and 99% (96-100%) vs. 73% (59-83%) (P = 0.001) for SPECT. The specificity (95% CI) of coronary CTA was 82% (63-93%) vs. 46% (30-64%) (P < 0.001) for XECG and 71% (60-80%) vs. 48% (31-64%) (P = 0.14) for SPECT. The odds ratio (OR) of downstream test utilization (DTU) for coronary CTA vs. XECG/SPECT was 1.38 (1.33-1.43, P < 0.001), for revascularization 2.63 (2.50-2.77, P < 0.001), for non-fatal myocardial infarction 0.53 (0.39-0.72, P < 0.001), and for all-cause mortality 1.01 (0.87-1.18, P = 0.87). The up-front diagnostic performance of coronary CTA is higher than of XECG and SPECT. When compared with XECG/SPECT testing, coronary CTA testing is associated with increased DTU and coronary revascularization. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2014. For permissions please email: journals.permissions@oup.com.

Diagnostic accuracy of level 3 portable sleep tests versus level 1 polysomnography for sleep-disordered breathing: a systematic review and meta-analysis

PubMed Central

El Shayeb, Mohamed; Topfer, Leigh-Ann; Stafinski, Tania; Pawluk, Lawrence; Menon, Devidas

2014-01-01

Background: Greater awareness of sleep-disordered breathing and rising obesity rates have fueled demand for sleep studies. Sleep testing using level 3 portable devices may expedite diagnosis and reduce the costs associated with level 1 in-laboratory polysomnography. We sought to assess the diagnostic accuracy of level 3 testing compared with level 1 testing and to identify the appropriate patient population for each test. Methods: We conducted a systematic review and meta-analysis of comparative studies of level 3 versus level 1 sleep tests in adults with suspected sleep-disordered breathing. We searched 3 research databases and grey literature sources for studies that reported on diagnostic accuracy parameters or disease management after diagnosis. Two reviewers screened the search results, selected potentially relevant studies and extracted data. We used a bivariate mixed-effects binary regression model to estimate summary diagnostic accuracy parameters. Results: We included 59 studies involving a total of 5026 evaluable patients (mostly patients suspected of having obstructive sleep apnea). Of these, 19 studies were included in the meta-analysis. The estimated area under the receiver operating characteristics curve was high, ranging between 0.85 and 0.99 across different levels of disease severity. Summary sensitivity ranged between 0.79 and 0.97, and summary specificity ranged between 0.60 and 0.93 across different apnea–hypopnea cut-offs. We saw no significant difference in the clinical management parameters between patients who underwent either test to receive their diagnosis. Interpretation: Level 3 portable devices showed good diagnostic performance compared with level 1 sleep tests in adult patients with a high pretest probability of moderate to severe obstructive sleep apnea and no unstable comorbidities. For patients suspected of having other types of sleep-disordered breathing or sleep disorders not related to breathing, level 1 testing remains the reference standard. PMID:24218531

Novel rapid molecular diagnosis of fetal chromosomal abnormalities associated with recurrent pregnancy loss.

PubMed

Yang, Lan; Tang, Ye; Lu, Mudan; Yang, Yuefen; Xiao, Jianping; Wang, Qiaoxia; Yang, Canfeng; Tao, Hehua; Xiang, Jingying

2016-12-01

Labor-intensive karyotyping is used as the reference standard diagnostic test to identify copy number variants (CNVs) in the fetal genome after recurrent pregnancy loss. Our aim was to present and evaluate a novel molecular assay called CNVplex that could potentially be used as an alternative method to conventional karyotyping for diagnosing fetal chromosomal abnormalities associated with recurrent pregnancy loss. Using karyotyping as the reference standard, CNVplex was performed to identify fetal chromosomal abnormalities in the chorionic villus samples from 76 women experiencing at least two pregnancy losses. Its diagnostic accuracy, sensitivity, and specificity were evaluated to detect aneuploidies associated with recurrent pregnancy loss. Turnaround time and costs of CNVplex were also measured. Diagnostic accuracy of CNVplex in aneuploidies that are associated with recurrent pregnancy loss was 1.0 (95% CI 0.94-1.0), sensitivity was 100% (95% CI 0.89-1.0), and specificity was 100% (95% CI 0.875-1.0). Diagnostic accuracy of CNVplex was similar to that of karyotyping. Both karyotyping and CNVplex assay detected 27 autosomal trisomies, three 45,X monosomies, and three polyploidies. CNVplex also detected additional novel structural abnormalities of the fetal genome. Compared with karyotyping, CNVplex significantly (p = 0.001) reduced the waiting time by 13.98 days (95% CI 13.88-14.08) and the cost by US $241 (95% CI 234.53-247.47). CNVplex is a novel effective assay for diagnosing fetal chromosomal abnormalities associated with recurrent pregnancy loss. In the routine clinical work-up of recurrent pregnancy loss, diagnostic accuracy of CNVplex is comparable to that of conventional karyotyping but it requires less waiting time and has lower cost. © 2016 Nordic Federation of Societies of Obstetrics and Gynecology.

Diagnostic accuracy of fine-needle aspiration cytology in Warthin tumors.

PubMed

Veder, Laura L; Kerrebijn, Jeroen D F; Smedts, Frank M; den Bakker, Michael A

2010-12-01

Our aim was to evaluate the diagnostic accuracy of fine-needle aspiration cytology (FNAC) for Warthin tumors of the parotid gland. All cytologic diagnoses of Warthin tumor between 1990 and 2007 were correlated with available histology. In addition, our results were compared to current literature. In 310 cases, Warthin tumor was diagnosed by FNAC. In 133 cases, (43%) both cytology and histology were available. In 127 of these 133 cases (95.5%), the diagnosis Warthin tumor was confirmed by histology. In 4 cases (3%), a benign lesion was diagnosed and 2 (1.5%) revealed a malignant lesion. On review, those cytologic diagnoses were not certain. In the literature, 11 missed malignancies (5.4%) in 202 cases were reported. The diagnostic accuracy of FNAC for the diagnosis of Warthin tumor is high and the percentage of missed malignant tumors is very low. Our results imply that a cytologic diagnosis of Warthin tumor may justify conservative treatment.

Myocardial perfusion imaging with PET

PubMed Central

Nakazato, Ryo; Berman, Daniel S; Alexanderson, Erick; Slomka, Piotr

2013-01-01

PET-myocardial perfusion imaging (MPI) allows accurate measurement of myocardial perfusion, absolute myocardial blood flow and function at stress and rest in a single study session performed in approximately 30 min. Various PET tracers are available for MPI, and rubidium-82 or nitrogen-13-ammonia is most commonly used. In addition, a new fluorine-18-based PET-MPI tracer is currently being evaluated. Relative quantification of PET perfusion images shows very high diagnostic accuracy for detection of obstructive coronary artery disease. Dynamic myocardial blood flow analysis has demonstrated additional prognostic value beyond relative perfusion imaging. Patient radiation dose can be reduced and image quality can be improved with latest advances in PET/CT equipment. Simultaneous assessment of both anatomy and perfusion by hybrid PET/CT can result in improved diagnostic accuracy. Compared with SPECT-MPI, PET-MPI provides higher diagnostic accuracy, using lower radiation doses during a shorter examination time period for the detection of coronary artery disease. PMID:23671459

Identification of coronary artery anatomy on dual-source cardiac computed tomography before arterial switch operation in newborns and young infants: comparison with transthoracic echocardiography.

PubMed

Goo, Hyun Woo

2018-02-01

Considering inherent limitations of transthoracic echocardiography, the diagnostic accuracy of cardiac CT in identifying coronary artery anatomy before arterial switch operation needs to be investigated with recently improved coronary artery visibility using electrocardiogram (ECG)-synchronized dual-source CT. To compare diagnostic accuracy between cardiac CT using a dual-source scanner and transthoracic echocardiography in identifying coronary artery anatomy before arterial switch operation in newborns and young infants. The study included 101 infants (median age 4 days, range 0 days to 10 months; M:F=78:23) who underwent ECG-synchronized cardiac dual-source CT and transthoracic echocardiography before arterial switch operation between July 2011 and December 2016. We evaluated and classified coronary artery anatomy on cardiac CT and transthoracic echocardiography. With the surgical findings as the reference standard, we compared the diagnostic accuracy for identifying coronary artery anatomy between cardiac CT and transthoracic echocardiography. The most common coronary artery pattern was the usual pattern (left coronary artery from sinus 1 and right coronary artery from sinus 2; 64.4%, 65/101), followed by a single coronary artery from sinus 2 and a conal branch from sinus 1 (7.9%, 8/101), the inverted pattern (5.9%, 6/101), the right coronary artery and left anterior descending artery from sinus 1 and the left circumflex artery from sinus 2 (5.9%, 6/101), and others. In 96 infants with surgically proven coronary artery anatomy, the diagnostic accuracy of cardiac CT was significantly higher than that of transthoracic echocardiography (91.7%, 88/96 vs. 54.2%, 52/96; P<0.0001). Diagnostic accuracy of cardiac CT is significantly higher than that of echocardiography in identifying coronary artery anatomy before arterial switch operation in newborns and young infants.

Accuracy of LightCycler(R) SeptiFast for the detection and identification of pathogens in the blood of patients with suspected sepsis: a systematic review protocol.

PubMed

Dark, Paul; Wilson, Claire; Blackwood, Bronagh; McAuley, Danny F; Perkins, Gavin D; McMullan, Ronan; Gates, Simon; Warhurst, Geoffrey

2012-01-01

Background There is growing interest in the potential utility of molecular diagnostics in improving the detection of life-threatening infection (sepsis). LightCycler® SeptiFast is a multipathogen probe-based real-time PCR system targeting DNA sequences of bacteria and fungi present in blood samples within a few hours. We report here the protocol of the first systematic review of published clinical diagnostic accuracy studies of this technology when compared with blood culture in the setting of suspected sepsis. Methods/design Data sources: the Cochrane Database of Systematic Reviews, the Database of Abstracts of Reviews of Effects (DARE), the Health Technology Assessment Database (HTA), the NHS Economic Evaluation Database (NHSEED), The Cochrane Library, MEDLINE, EMBASE, ISI Web of Science, BIOSIS Previews, MEDION and the Aggressive Research Intelligence Facility Database (ARIF). diagnostic accuracy studies that compare the real-time PCR technology with standard culture results performed on a patient's blood sample during the management of sepsis. three reviewers, working independently, will determine the level of evidence, methodological quality and a standard data set relating to demographics and diagnostic accuracy metrics for each study. Statistical analysis/data synthesis: heterogeneity of studies will be investigated using a coupled forest plot of sensitivity and specificity and a scatter plot in Receiver Operator Characteristic (ROC) space. Bivariate model method will be used to estimate summary sensitivity and specificity. The authors will investigate reporting biases using funnel plots based on effective sample size and regression tests of asymmetry. Subgroup analyses are planned for adults, children and infection setting (hospital vs community) if sufficient data are uncovered. Dissemination Recommendations will be made to the Department of Health (as part of an open-access HTA report) as to whether the real-time PCR technology has sufficient clinical diagnostic accuracy potential to move forward to efficacy testing during the provision of routine clinical care. Registration PROSPERO-NIHR Prospective Register of Systematic Reviews (CRD42011001289).

Diagnostic accuracy of a clinical diagnosis of idiopathic pulmonary fibrosis: an international case–cohort study

PubMed Central

Maher, Toby M.; Kolb, Martin; Poletti, Venerino; Nusser, Richard; Richeldi, Luca; Vancheri, Carlo; Wilsher, Margaret L.; Antoniou, Katerina M.; Behr, Jüergen; Bendstrup, Elisabeth; Brown, Kevin; Calandriello, Lucio; Corte, Tamera J.; Crestani, Bruno; Flaherty, Kevin; Glaspole, Ian; Grutters, Jan; Inoue, Yoshikazu; Kokosi, Maria; Kondoh, Yasuhiro; Kouranos, Vasileios; Kreuter, Michael; Johannson, Kerri; Judge, Eoin; Ley, Brett; Margaritopoulos, George; Martinez, Fernando J.; Molina-Molina, Maria; Morais, António; Nunes, Hilario; Raghu, Ganesh; Ryerson, Christopher J.; Selman, Moises; Spagnolo, Paolo; Taniguchi, Hiroyuki; Tomassetti, Sara; Valeyre, Dominique; Wijsenbeek, Marlies; Wuyts, Wim; Hansell, David; Wells, Athol

2017-01-01

We conducted an international study of idiopathic pulmonary fibrosis (IPF) diagnosis among a large group of physicians and compared their diagnostic performance to a panel of IPF experts. A total of 1141 respiratory physicians and 34 IPF experts participated. Participants evaluated 60 cases of interstitial lung disease (ILD) without interdisciplinary consultation. Diagnostic agreement was measured using the weighted kappa coefficient (κw). Prognostic discrimination between IPF and other ILDs was used to validate diagnostic accuracy for first-choice diagnoses of IPF and were compared using the C-index. A total of 404 physicians completed the study. Agreement for IPF diagnosis was higher among expert physicians (κw=0.65, IQR 0.53–0.72, p<0.0001) than academic physicians (κw=0.56, IQR 0.45–0.65, p<0.0001) or physicians with access to multidisciplinary team (MDT) meetings (κw=0.54, IQR 0.45–0.64, p<0.0001). The prognostic accuracy of academic physicians with >20 years of experience (C-index=0.72, IQR 0.0–0.73, p=0.229) and non-university hospital physicians with more than 20 years of experience, attending weekly MDT meetings (C-index=0.72, IQR 0.70–0.72, p=0.052), did not differ significantly (p=0.229 and p=0.052 respectively) from the expert panel (C-index=0.74 IQR 0.72–0.75). Experienced respiratory physicians at university-based institutions diagnose IPF with similar prognostic accuracy to IPF experts. Regular MDT meeting attendance improves the prognostic accuracy of experienced non-university practitioners to levels achieved by IPF experts. PMID:28860269

Diagnostic Accuracy of Coronary Computed Tomography Before Aortic Valve Replacement: Systematic Review and Meta-Analysis.

PubMed

Chaikriangkrai, Kongkiat; Jhun, Hye Yeon; Shantha, Ghanshyam Palamaner Subash; Abdulhak, Aref Bin; Tandon, Rudhir; Alqasrawi, Musab; Klappa, Anthony; Pancholy, Samir; Deshmukh, Abhishek; Bhama, Jay; Sigurdsson, Gardar

2018-07-01

In aortic stenosis patients referred for surgical and transcatheter aortic valve replacement (AVR), the evidence of diagnostic accuracy of coronary computed tomography angiography (CCTA) has been limited. The objective of this study was to investigate the diagnostic accuracy of CCTA for significant coronary artery disease (CAD) in patients referred for AVR using invasive coronary angiography (ICA) as the gold standard. We searched databases for all diagnostic studies of CCTA in patients referred for AVR, which reported diagnostic testing characteristics on patient-based analysis required to pool summary sensitivity, specificity, positive-likelihood ratio, and negative-likelihood ratio. Significant CAD in both CCTA and ICA was defined by >50% stenosis in any coronary artery, coronary stent, or bypass graft. Thirteen studies evaluated 1498 patients (mean age, 74 y; 47% men; 76% transcatheter AVR). The pooled prevalence of significant stenosis determined by ICA was 43%. Hierarchical summary receiver-operating characteristic analysis demonstrated a summary area under curve of 0.96. The pooled sensitivity, specificity, and positive-likelihood and negative-likelihood ratios of CCTA in identifying significant stenosis determined by ICA were 95%, 79%, 4.48, and 0.06, respectively. In subgroup analysis, the diagnostic profiles of CCTA were comparable between surgical and transcatheter AVR. Despite the higher prevalence of significant CAD in patients with aortic stenosis than with other valvular heart diseases, our meta-analysis has shown that CCTA has a suitable diagnostic accuracy profile as a gatekeeper test for ICA. Our study illustrates a need for further study of the potential role of CCTA in preoperative planning for AVR.

Effects of disease severity distribution on the performance of quantitative diagnostic methods and proposal of a novel 'V-plot' methodology to display accuracy values.

PubMed

Petraco, Ricardo; Dehbi, Hakim-Moulay; Howard, James P; Shun-Shin, Matthew J; Sen, Sayan; Nijjer, Sukhjinder S; Mayet, Jamil; Davies, Justin E; Francis, Darrel P

2018-01-01

Diagnostic accuracy is widely accepted by researchers and clinicians as an optimal expression of a test's performance. The aim of this study was to evaluate the effects of disease severity distribution on values of diagnostic accuracy as well as propose a sample-independent methodology to calculate and display accuracy of diagnostic tests. We evaluated the diagnostic relationship between two hypothetical methods to measure serum cholesterol (Chol rapid and Chol gold ) by generating samples with statistical software and (1) keeping the numerical relationship between methods unchanged and (2) changing the distribution of cholesterol values. Metrics of categorical agreement were calculated (accuracy, sensitivity and specificity). Finally, a novel methodology to display and calculate accuracy values was presented (the V-plot of accuracies). No single value of diagnostic accuracy can be used to describe the relationship between tests, as accuracy is a metric heavily affected by the underlying sample distribution. Our novel proposed methodology, the V-plot of accuracies, can be used as a sample-independent measure of a test performance against a reference gold standard.

A systematic review of the PTSD Checklist's diagnostic accuracy studies using QUADAS.

PubMed

McDonald, Scott D; Brown, Whitney L; Benesek, John P; Calhoun, Patrick S

2015-09-01

Despite the popularity of the PTSD Checklist (PCL) as a clinical screening test, there has been no comprehensive quality review of studies evaluating its diagnostic accuracy. A systematic quality assessment of 22 diagnostic accuracy studies of the English-language PCL using the Quality Assessment of Diagnostic Accuracy Studies (QUADAS) assessment tool was conducted to examine (a) the quality of diagnostic accuracy studies of the PCL, and (b) whether quality has improved since the 2003 STAndards for the Reporting of Diagnostic accuracy studies (STARD) initiative regarding reporting guidelines for diagnostic accuracy studies. Three raters independently applied the QUADAS tool to each study, and a consensus among the 4 authors is reported. Findings indicated that although studies generally met standards in several quality areas, there is still room for improvement. Areas for improvement include establishing representativeness, adequately describing clinical and demographic characteristics of the sample, and presenting better descriptions of important aspects of test and reference standard execution. Only 2 studies met each of the 14 quality criteria. In addition, study quality has not appreciably improved since the publication of the STARD Statement in 2003. Recommendations for the improvement of diagnostic accuracy studies of the PCL are discussed. (c) 2015 APA, all rights reserved).

ECG Rhythm Analysis with Expert and Learner-Generated Schemas in Novice Learners

ERIC Educational Resources Information Center

Blissett, Sarah; Cavalcanti, Rodrigo; Sibbald, Matthew

2015-01-01

Although instruction using expert-generated schemas is associated with higher diagnostic performance, implementation is resource intensive. Learner-generated schemas are an alternative, but may be limited by increases in cognitive load. We compared expert- and learner-generated schemas for learning ECG rhythm interpretation on diagnostic accuracy,…

STARD 2015: An Updated List of Essential Items for Reporting Diagnostic Accuracy Studies.

PubMed

Bossuyt, Patrick M; Reitsma, Johannes B; Bruns, David E; Gatsonis, Constantine A; Glasziou, Paul P; Irwig, Les; Lijmer, Jeroen G; Moher, David; Rennie, Drummond; de Vet, Henrica C W; Kressel, Herbert Y; Rifai, Nader; Golub, Robert M; Altman, Douglas G; Hooft, Lotty; Korevaar, Daniël A; Cohen, Jérémie F

2015-12-01

Incomplete reporting has been identified as a major source of avoidable waste in biomedical research. Essential information is often not provided in study reports, impeding the identification, critical appraisal, and replication of studies. To improve the quality of reporting of diagnostic accuracy studies, the Standards for Reporting of Diagnostic Accuracy Studies (STARD) statement was developed. Here we present STARD 2015, an updated list of 30 essential items that should be included in every report of a diagnostic accuracy study. This update incorporates recent evidence about sources of bias and variability in diagnostic accuracy and is intended to facilitate the use of STARD. As such, STARD 2015 may help to improve completeness and transparency in reporting of diagnostic accuracy studies. © 2015 American Association for Clinical Chemistry.

Rolling bearing fault diagnosis based on information fusion using Dempster-Shafer evidence theory

NASA Astrophysics Data System (ADS)

Pei, Di; Yue, Jianhai; Jiao, Jing

2017-10-01

This paper presents a fault diagnosis method for rolling bearing based on information fusion. Acceleration sensors are arranged at different position to get bearing vibration data as diagnostic evidence. The Dempster-Shafer (D-S) evidence theory is used to fuse multi-sensor data to improve diagnostic accuracy. The efficiency of the proposed method is demonstrated by the high speed train transmission test bench. The results of experiment show that the proposed method in this paper improves the rolling bearing fault diagnosis accuracy compared with traditional signal analysis methods.

Hounsfield Unit inaccuracy in computed tomography lesion size and density, diagnostic quality vs attenuation correction

NASA Astrophysics Data System (ADS)

Szczepura, Katy; Thompson, John; Manning, David

2017-03-01

In computed tomography the Hounsfield Units (HU) are used as an indicator of the tissue type based on the linear attenuation coefficients of the tissue. HU accuracy is essential when this metric is used in any form to support diagnosis. In hybrid imaging, such as SPECT/CT and PET/CT, the information is used for attenuation correction (AC) of the emission images. This work investigates the HU accuracy of nodules of known size and HU, comparing diagnostic quality (DQ) images with images used for AC.

Diagnostic accuracy of MRI in the measurement of glenoid bone loss.

PubMed

Gyftopoulos, Soterios; Hasan, Saqib; Bencardino, Jenny; Mayo, Jason; Nayyar, Samir; Babb, James; Jazrawi, Laith

2012-10-01

The purpose of this study is to assess the accuracy of MRI quantification of glenoid bone loss and to compare the diagnostic accuracy of MRI to CT in the measurement of glenoid bone loss. MRI, CT, and 3D CT examinations of 18 cadaveric glenoids were obtained after the creation of defects along the anterior and anteroinferior glenoid. The defects were measured by three readers separately and blindly using the circle method. These measurements were compared with measurements made on digital photographic images of the cadaveric glenoids. Paired sample Student t tests were used to compare the imaging modalities. Concordance correlation coefficients were also calculated to measure interobserver agreement. Our data show that MRI could be used to accurately measure glenoid bone loss with a small margin of error (mean, 3.44%; range, 2.06-5.94%) in estimated percentage loss. MRI accuracy was similar to that of both CT and 3D CT for glenoid loss measurements in our study for the readers familiar with the circle method, with 1.3% as the maximum expected difference in accuracy of the percentage bone loss between the different modalities (95% confidence). Glenoid bone loss can be accurately measured on MRI using the circle method. The MRI quantification of glenoid bone loss compares favorably to measurements obtained using 3D CT and CT. The accuracy of the measurements correlates with the level of training, and a learning curve is expected before mastering this technique.

Competency-based assessment in surgeon-performed head and neck ultrasonography: A validity study.

PubMed

Todsen, Tobias; Melchiors, Jacob; Charabi, Birgitte; Henriksen, Birthe; Ringsted, Charlotte; Konge, Lars; von Buchwald, Christian

2018-06-01

Head and neck ultrasonography (HNUS) increasingly is used as a point-of-care diagnostic tool by otolaryngologists. However, ultrasonography (US) is a very operator-dependent image modality. Hence, this study aimed to explore the diagnostic accuracy of surgeon-performed HNUS and to establish validity evidence for an objective structured assessment of ultrasound skills (OSAUS) used for competency-based assessment. A prospective experimental study. Six otolaryngologists and 11 US novices were included in a standardized test setup for which they had to perform focused HNUS of eight patients suspected for different head and neck lesions. Their diagnostic accuracy was calculated based on the US reports, and two blinded raters assessed the video-recorded US performance using the OSAUS scale. The otolaryngologists obtained a high diagnostic accuracy on 88% (range 63%-100%) compared to the US novices on 38% (range 0-63%); P < 0.001. The OSAUS score demonstrated good inter-case reliability (0.85) and inter-rater reliability (0.76), and significant discrimination between otolaryngologist and US novices; P < 0.001. A strong correlation between the OSAUS score and the diagnostic accuracy was found (Spearman's ρ, 0.85; P < P 0.001), and a pass/fail score was established at 2.8. Strong validity evidence supported the use of the OSAUS scale to assess HNUS competence with good reliability, significant discrimination between US competence levels, and a strong correlation of assessment score to diagnostic accuracy. An OSAUS pass/fail score was established and could be used for competence-based assessment in surgeon-performed HNUS. NA. Laryngoscope, 128:1346-1352, 2018. © 2017 The American Laryngological, Rhinological and Otological Society, Inc.

BRIEF REPORT: Beyond Clinical Experience: Features of Data Collection and Interpretation That Contribute to Diagnostic Accuracy

PubMed Central

Nendaz, Mathieu R; Gut, Anne M; Perrier, Arnaud; Louis-Simonet, Martine; Blondon-Choa, Katherine; Herrmann, François R; Junod, Alain F; Vu, Nu V

2006-01-01

BACKGROUND Clinical experience, features of data collection process, or both, affect diagnostic accuracy, but their respective role is unclear. OBJECTIVE, DESIGN Prospective, observational study, to determine the respective contribution of clinical experience and data collection features to diagnostic accuracy. METHODS Six Internists, 6 second year internal medicine residents, and 6 senior medical students worked up the same 7 cases with a standardized patient. Each encounter was audiotaped and immediately assessed by the subjects who indicated the reasons underlying their data collection. We analyzed the encounters according to diagnostic accuracy, information collected, organ systems explored, diagnoses evaluated, and final decisions made, and we determined predictors of diagnostic accuracy by logistic regression models. RESULTS Several features significantly predicted diagnostic accuracy after correction for clinical experience: early exploration of correct diagnosis (odds ratio [OR] 24.35) or of relevant diagnostic hypotheses (OR 2.22) to frame clinical data collection, larger number of diagnostic hypotheses evaluated (OR 1.08), and collection of relevant clinical data (OR 1.19). CONCLUSION Some features of data collection and interpretation are related to diagnostic accuracy beyond clinical experience and should be explicitly included in clinical training and modeled by clinical teachers. Thoroughness in data collection should not be considered a privileged way to diagnostic success. PMID:17105525

Combining independent decisions increases diagnostic accuracy of reading lumbosacral radiographs and magnetic resonance imaging.

PubMed

Kurvers, Ralf H J M; de Zoete, Annemarie; Bachman, Shelby L; Algra, Paul R; Ostelo, Raymond

2018-01-01

Diagnosing the causes of low back pain is a challenging task, prone to errors. A novel approach to increase diagnostic accuracy in medical decision making is collective intelligence, which refers to the ability of groups to outperform individual decision makers in solving problems. We investigated whether combining the independent ratings of chiropractors, chiropractic radiologists and medical radiologists can improve diagnostic accuracy when interpreting diagnostic images of the lumbosacral spine. Evaluations were obtained from two previously published studies: study 1 consisted of 13 raters independently rating 300 lumbosacral radiographs; study 2 consisted of 14 raters independently rating 100 lumbosacral magnetic resonance images. In both studies, raters evaluated the presence of "abnormalities", which are indicators of a serious health risk and warrant immediate further examination. We combined independent decisions of raters using a majority rule which takes as final diagnosis the decision of the majority of the group. We compared the performance of the majority rule to the performance of single raters. Our results show that with increasing group size (i.e., increasing the number of independent decisions) both sensitivity and specificity increased in both data-sets, with groups consistently outperforming single raters. These results were found for radiographs and MR image reading alike. Our findings suggest that combining independent ratings can improve the accuracy of lumbosacral diagnostic image reading.

Immunohistochemical identification of varicella-zoster virus gene 63-encoded protein (IE63) and late (gE) protein on smears and cutaneous biopsies: implications for diagnostic use.

PubMed

Nikkels, A F; Debrus, S; Sadzot-Delvaux, C; Piette, J; Rentier, B; Piérard, G E

1995-12-01

Early and specific recognition of varicella zoster virus (VZV) infection is of vital concern in immunocompromised patients. The aim of this study was to compare the diagnostic accuracy of histochemical and immunohistochemical identification of the VZV ORF63 encoded protein (IE63) and of the VZV late protein gE on smears and formalin-fixed paraffin-embedded skin sections taken from lesions clinically diagnosed as varicella (n = 15) and herpes zoster (n = 51). Microscopic examinations of Tzanck smears and skin sections yielded a diagnostic accuracy of Herpesviridae infections in 66.7% (10/15) and 92.3% (12/13) of varicella, and 74.4% (29/39) and 87.8% (43/49) of herpes zoster, respectively. Immunohistochemistry applied to varicella provided a type-specific virus diagnostic accuracy of 86.7% (13/15; IE63) and 100% (15/15; gE) on smears, and of 92.3% for both VZV proteins on skin sections. In herpes zoster, the diagnostic accuracy of immunohistochemistry reached 92.3% (36/39; IE63) and 94.9% (37/39; gE) on smears, and 91.7% (44/48; IE63) and 91.8% (45/49; gE) on skin sections. These findings indicate that the immunohistochemical detection of IE63 and gE on both smears and skin sections yields a higher specificity and sensitivity than standard microscopic assessments.

Diagnostic Accuracy of Rating Scales for Attention-Deficit/Hyperactivity Disorder: A Meta-analysis.

PubMed

Chang, Ling-Yin; Wang, Mei-Yeh; Tsai, Pei-Shan

2016-03-01

The Child Behavior Checklist-Attention Problem (CBCL-AP) scale and Conners Rating Scale-Revised (CRS-R) are commonly used behavioral rating scales for diagnosing attention-deficit/hyperactivity disorder (ADHD) in children and adolescents. To evaluate and compare the diagnostic performance of CBCL-AP and CRS-R in diagnosing ADHD in children and adolescents. PubMed, Ovid Medline, and other relevant electronic databases were searched for articles published up to May 2015. We included studies evaluating the diagnostic performance of either CBCL-AP scale or CRS-R for diagnosing ADHD in pediatric populations in comparison with a defined reference standard. Bivariate random effects models were used for pooling and comparing diagnostic performance. We identified and evaluated 14 and 11 articles on CBCL-AP and CRS-R, respectively. The results revealed pooled sensitivities of 0.77, 0.75, 0.72, and 0.83 and pooled specificities of 0.73, 0.75, 0.84, and 0.84 for CBCL-AP, Conners Parent Rating Scale-Revised, Conners Teacher Rating Scale-Revised, and Conners Abbreviated Symptom Questionnaire (ASQ), respectively. No difference was observed in the diagnostic performance of the various scales. Study location, age of participants, and percentage of female participants explained the heterogeneity in the specificity of the CBCL-AP. CBCL-AP and CRS-R both yielded moderate sensitivity and specificity in diagnosing ADHD. According to the comparable diagnostic performance of all examined scales, ASQ may be the most effective diagnostic tool in assessing ADHD because of its brevity and high diagnostic accuracy. CBCL is recommended for more comprehensive assessments. Copyright © 2016 by the American Academy of Pediatrics.

Comparative analysis of ERCP, IDUS, EUS and CT in predicting malignant bile duct strictures

PubMed Central

Heinzow, Hauke S; Kammerer, Sara; Rammes, Carina; Wessling, Johannes; Domagk, Dirk; Meister, Tobias

2014-01-01

AIM: To compare endoscopic retrograde cholangio-pancreatography (ERCP), intraductal ultrasound (IDUS), endosonography (EUS), endoscopic transpapillary forceps biopsies (ETP) and computed tomography (CT) with respect to diagnosing malignant bile duct strictures. METHODS: A patient cohort with bile duct strictures of unknown etiology was examined by ERCP and IDUS, ETP, EUS, and CT. The sensitivity, specificity, and accuracy rates of the diagnostic procedures were calculated based on the definite diagnoses proved by histopathology or long-term follow-up in those patients who did not undergo surgery. For each of the diagnostic measures, the sensitivity, specificity, and accuracy rates were calculated. In all cases, the gold standard was the histopathologic staging of specimens or long-term follow-up of at least 12 mo. A comparison of the accuracy rates between the localization of strictures was performed by using the Mann-Whitney U-test and the χ2 test as appropriate. A comparison of the accuracy rates between the diagnostic procedures was performed by using the McNemar’s test. Differences were considered statistically significant if P < 0.05. RESULTS: A total of 234 patients (127 males, 107 females, median age 64, range 20-90 years) with indeterminate bile duct strictures were included. A total of 161 patients underwent operative exploration; thus, a surgical histopathological correlation was available for those patients. A total of 113 patients had malignant disease proven by surgery; in 48 patients, benign disease was surgically found. In these patients, the decision for surgical exploration was made due to the suspicion of malignant disease in multimodal diagnostics (ERCP, CT, or EUS). Fifty patients had a benign diagnosis and were followed by a surveillance protocol with a follow-up of at least 12 mo; the median follow-up was 34 mo. Twenty-three patients had extended malignant disease, and thus were considered palliative. A comparison of the different diagnostic tools for detecting bile duct malignancy resulted in accuracy rates of 91% (ERCP/IDUS), 59% (ETP), 92% (IDUS + ETP), 74% (EUS), and 73% (CT), respectively. In the subgroup analysis, the accuracy rates (%, ERCP + IDUS/ETP/IDUS + ETP; EUS; CT) for each tumor entity were as follows: cholangiocellular carcinoma: 92%/74%/92%/70%/79%; pancreatic carcinoma: 90%/68%/90%/81%/76%; and ampullary carcinoma: 88%/90%/90%/76%/76%. The detection rate of malignancy by ERCP/IDUS was superior to ETP (91% vs 59%, P < 0.0001), EUS (91% vs 74%, P < 0.0001) and CT (91% vs 73%, P < 0.0001); EUS was comparable to CT (74% vs 73%, P = 0.649). When analyzing accuracy rates with regard to localization of the bile duct stenosis, the accuracy rate of EUS for proximal vs distal stenosis was significantly higher for distal stenosis (79% vs 57%, P < 0.0001). CONCLUSION: ERCP/IDUS is superior to EUS and CT in providing accurate diagnoses of bile duct strictures of uncertain etiology. Multimodal diagnostics is recommended. PMID:25132767

Emergency department CT screening of patients with nontraumatic neurological symptoms referred to the posterior fossa: comparison of thin versus thick slice images.

PubMed

Kamalian, Shervin; Atkinson, Wendy L; Florin, Lauren A; Pomerantz, Stuart R; Lev, Michael H; Romero, Javier M

2014-06-01

Evaluation of the posterior fossa (PF) on 5-mm-thick helical CT images (current default) has improved diagnostic accuracy compared to 5-mm sequential CT images; however, 5-mm-thick images may not be ideal for PF pathology due to volume averaging of rapid changes in anatomy in the Z-direction. Therefore, we sought to determine if routine review of 1.25-mm-thin helical CT images has superior accuracy in screening for nontraumatic PF pathology. MRI proof of diagnosis was obtained within 6 h of helical CT acquisition for 90 consecutive ED patients with, and 88 without, posterior fossa lesions. Helical CT images were post-processed at 1.25 and 5-mm-axial slice thickness. Two neuroradiologists blinded to the clinical/MRI findings reviewed both image sets. Interobserver agreement and accuracy were rated using Kappa statistics and ROC analysis, respectively. Of the 90/178 (51 %) who were MR positive, 60/90 (66 %) had stroke and 30/90 (33 %) had other etiologies. There was excellent interobserver agreement (κ > 0.97) for both thick and thin slice assessments. The accuracy, sensitivity, and specificity for 1.25-mm images were 65, 44, and 84 %, respectively, and for 5-mm images were 67, 45, and 85 %, respectively. The diagnostic accuracy was not significantly different (p > 0.5). In this cohort of patients with nontraumatic neurological symptoms referred to the posterior fossa, 1.25-mm-thin slice CT reformatted images do not have superior accuracy compared to 5-mm-thick images. This information has implications on optimizing resource utilizations and efficiency in a busy emergency room. Review of 1.25-mm-thin images may help diagnostic accuracy only when review of 5-mm-thick images as current default is inconclusive.

Teledermatology consultation using a smartphone multimedia messaging service for common skin diseases in the Korean army: a clinical evaluation of its diagnostic accuracy.

PubMed

Shin, Hyoseung; Kim, Dong Hyun; Ryu, Hyeong Ho; Yoon, So Young; Jo, Seong Jin

2014-03-01

We evaluated the diagnostic accuracy of teleconsultations for skin diseases common in the army using a smartphone multimedia messaging service (MMS). Images of skin lesions were obtained from 100 army patients using digital cameras built into smartphones. Three remotely located dermatologists received the dermatology images and associated clinical information via the MMS. The teledermatologists' diagnoses were compared with those obtained from face-to-face examinations. The three most common diagnoses made at the dermatology clinics were eczema, viral warts and fungal infections. The mean diagnostic agreement between face-to-face and teledermatology consultations was 71% (SD 2). The mean kappa coefficient was 0.73 (SD 0.06) for the three most common diagnostic categories. The mean values for sensitivity were 78% (SD 0), 88% (SD 21) and 61% (SD 11) for eczema, viral warts and fungal infections, respectively, and the specificity values were above 90% for these skin diseases. Teledermatology consultation using smartphones is simple. Although diagnoses using telemedicine do not perfectly match diagnoses from face-to-face consultations the diagnostic accuracy using smartphones is superior to that of clinicians who are not specialized in dermatology.

Rapid, comprehensive, and affordable mycobacterial diagnosis with whole-genome sequencing: a prospective study

PubMed Central

Pankhurst, Louise J; del Ojo Elias, Carlos; Votintseva, Antonina A; Walker, Timothy M; Cole, Kevin; Davies, Jim; Fermont, Jilles M; Gascoyne-Binzi, Deborah M; Kohl, Thomas A; Kong, Clare; Lemaitre, Nadine; Niemann, Stefan; Paul, John; Rogers, Thomas R; Roycroft, Emma; Smith, E Grace; Supply, Philip; Tang, Patrick; Wilcox, Mark H; Wordsworth, Sarah; Wyllie, David; Xu, Li; Crook, Derrick W

2016-01-01

Summary Background Slow and cumbersome laboratory diagnostics for Mycobacterium tuberculosis complex (MTBC) risk delayed treatment and poor patient outcomes. Whole-genome sequencing (WGS) could potentially provide a rapid and comprehensive diagnostic solution. In this prospective study, we compare real-time WGS with routine MTBC diagnostic workflows. Methods We compared sequencing mycobacteria from all newly positive liquid cultures with routine laboratory diagnostic workflows across eight laboratories in Europe and North America for diagnostic accuracy, processing times, and cost between Sept 6, 2013, and April 14, 2014. We sequenced specimens once using local Illumina MiSeq platforms and processed data centrally using a semi-automated bioinformatics pipeline. We identified species or complex using gene presence or absence, predicted drug susceptibilities from resistance-conferring mutations identified from reference-mapped MTBC genomes, and calculated genetic distance to previously sequenced UK MTBC isolates to detect outbreaks. WGS data processing and analysis was done by staff masked to routine reference laboratory and clinical results. We also did a microcosting analysis to assess the financial viability of WGS-based diagnostics. Findings Compared with routine results, WGS predicted species with 93% (95% CI 90–96; 322 of 345 specimens; 356 mycobacteria specimens submitted) accuracy and drug susceptibility also with 93% (91–95; 628 of 672 specimens; 168 MTBC specimens identified) accuracy, with one sequencing attempt. WGS linked 15 (16% [95% CI 10–26]) of 91 UK patients to an outbreak. WGS diagnosed a case of multidrug-resistant tuberculosis before routine diagnosis was completed and discovered a new multidrug-resistant tuberculosis cluster. Full WGS diagnostics could be generated in a median of 9 days (IQR 6–10), a median of 21 days (IQR 14–32) faster than final reference laboratory reports were produced (median of 31 days [IQR 21–44]), at a cost of £481 per culture-positive specimen, whereas routine diagnosis costs £518, equating to a WGS-based diagnosis cost that is 7% cheaper annually than are present diagnostic workflows. Interpretation We have shown that WGS has a scalable, rapid turnaround, and is a financially feasible method for full MTBC diagnostics. Continued improvements to mycobacterial processing, bioinformatics, and analysis will improve the accuracy, speed, and scope of WGS-based diagnosis. Funding National Institute for Health Research, Department of Health, Wellcome Trust, British Colombia Centre for Disease Control Foundation for Population and Public Health, Department of Clinical Microbiology, Trinity College Dublin. PMID:26669893

A Web-Based Education Program for Colorectal Lesion Diagnosis with Narrow Band Imaging Classification.

PubMed

Aihara, Hiroyuki; Kumar, Nitin; Thompson, Christopher C

2018-04-19

An education system for narrow band imaging (NBI) interpretation requires sufficient exposure to key features. However, access to didactic lectures by experienced teachers is limited in the United States. To develop and assess the effectiveness of a colorectal lesion identification tutorial. In the image analysis pretest, subjects including 9 experts and 8 trainees interpreted 50 white light (WL) and 50 NBI images of colorectal lesions. Results were not reviewed with subjects. Trainees then participated in an online tutorial emphasizing NBI interpretation in colorectal lesion analysis. A post-test was administered and diagnostic yields were compared to pre-education diagnostic yields. Under the NBI mode, experts showed higher diagnostic yields (sensitivity 91.5% [87.3-94.4], specificity 90.6% [85.1-94.2], and accuracy 91.1% [88.5-93.7] with substantial interobserver agreement [κ value 0.71]) compared to trainees (sensitivity 89.6% [84.8-93.0], specificity 80.6% [73.5-86.3], and accuracy 86.0% [82.6-89.2], with substantial interobserver agreement [κ value 0.69]). The online tutorial improved the diagnostic yields of trainees to the equivalent level of experts (sensitivity 94.1% [90.0-96.6], specificity 89.0% [83.0-93.2], and accuracy 92.0% [89.3-94.7], p < 0.001 with substantial interobserver agreement [κ value 0.78]). This short, online tutorial improved diagnostic performance and interobserver agreement. © 2018 S. Karger AG, Basel.

Partial verification bias and incorporation bias affected accuracy estimates of diagnostic studies for biomarkers that were part of an existing composite gold standard.

PubMed

Karch, Annika; Koch, Armin; Zapf, Antonia; Zerr, Inga; Karch, André

2016-10-01

To investigate how choice of gold standard biases estimates of sensitivity and specificity in studies reassessing the diagnostic accuracy of biomarkers that are already part of a lifetime composite gold standard (CGS). We performed a simulation study based on the real-life example of the biomarker "protein 14-3-3" used for diagnosing Creutzfeldt-Jakob disease. Three different types of gold standard were compared: perfect gold standard "autopsy" (available in a small fraction only; prone to partial verification bias), lifetime CGS (including the biomarker under investigation; prone to incorporation bias), and "best available" gold standard (autopsy if available, otherwise CGS). Sensitivity was unbiased when comparing 14-3-3 with autopsy but overestimated when using CGS or "best available" gold standard. Specificity of 14-3-3 was underestimated in scenarios comparing 14-3-3 with autopsy (up to 24%). In contrast, overestimation (up to 20%) was observed for specificity compared with CGS; this could be reduced to 0-10% when using the "best available" gold standard. Choice of gold standard affects considerably estimates of diagnostic accuracy. Using the "best available" gold standard (autopsy where available, otherwise CGS) leads to valid estimates of specificity, whereas sensitivity is estimated best when tested against autopsy alone. Copyright © 2016 Elsevier Inc. All rights reserved.

Combining diffusion-weighted MRI with Gd-EOB-DTPA-enhanced MRI improves the detection of colorectal liver metastases.

PubMed

Koh, D-M; Collins, D J; Wallace, T; Chau, I; Riddell, A M

2012-07-01

To compare the diagnostic accuracy of gadolinium-ethoxybenzyl-diethylenetriaminepentaacetic acid (Gd-EOB-DTPA)-enhanced MRI, diffusion-weighted MRI (DW-MRI) and a combination of both techniques for the detection of colorectal hepatic metastases. 72 patients with suspected colorectal liver metastases underwent Gd-EOB-DTPA MRI and DW-MRI. Images were retrospectively reviewed with unenhanced T(1) and T(2) weighted images as Gd-EOB-DTPA image set, DW-MRI image set and combined image set by two independent radiologists. Each lesion detected was scored for size, location and likelihood of metastasis, and compared with surgery and follow-up imaging. Diagnostic accuracy was compared using receiver operating characteristics and interobserver agreement by kappa statistics. 417 lesions (310 metastases, 107 benign) were found in 72 patients. For both readers, diagnostic accuracy using the combined image set was higher [area under the curve (Az)=0.96, 0.97] than Gd-EOB-DTPA image set (Az=0.86, 0.89) or DW-MRI image set (Az=0.93, 0.92). Using combined image set improved identification of liver metastases compared with Gd-EOB-DTPA image set (p<0.001) or DW-MRI image set (p<0.001). There was very good interobserver agreement for lesion classification (κ=0.81-0.88). Combining DW-MRI with Gd-EOB-DTPA-enhanced T(1) weighted MRI significantly improved the detection of colorectal liver metastases.

Independent value of image fusion in unenhanced breast MRI using diffusion-weighted and morphological T2-weighted images for lesion characterization in patients with recently detected BI-RADS 4/5 x-ray mammography findings.

PubMed

Bickelhaupt, Sebastian; Tesdorff, Jana; Laun, Frederik Bernd; Kuder, Tristan Anselm; Lederer, Wolfgang; Teiner, Susanne; Maier-Hein, Klaus; Daniel, Heidi; Stieber, Anne; Delorme, Stefan; Schlemmer, Heinz-Peter

2017-02-01

The aim of this study was to evaluate the accuracy and applicability of solitarily reading fused image series of T2-weighted and high-b-value diffusion-weighted sequences for lesion characterization as compared to sequential or combined image analysis of these unenhanced sequences and to contrast- enhanced breast MRI. This IRB-approved study included 50 female participants with suspicious breast lesions detected in screening X-ray mammograms, all of which provided written informed consent. Prior to biopsy, all women underwent MRI including diffusion-weighted imaging (DWIBS, b = 1500s/mm 2 ). Images were analyzed as follows: prospective image fusion of DWIBS and T2-weighted images (FU), side-by-side analysis of DWIBS and T2-weighted series (CO), combination of the first two methods (CO+FU), and full contrast-enhanced diagnostic protocol (FDP). Diagnostic indices, confidence, and image quality of the protocols were compared by two blinded readers. Reading the CO+FU (accuracy 0.92; NPV 96.1 %; PPV 87.6 %) and the CO series (0.90; 96.1 %; 83.7 %) provided a diagnostic performance similar to the FDP (0.95; 96.1 %; 91.3 %; p > 0.05). FU reading alone significantly reduced the diagnostic accuracy (0.82; 93.3 %; 73.4 %; p = 0.023). MR evaluation of suspicious BI-RADS 4 and 5 lesions detected on mammography by using a non-contrast-enhanced T2-weighted and DWIBS sequence protocol is most accurate if MR images were read using the CO+FU protocol. • Unenhanced breast MRI with additional DWIBS/T2w-image fusion allows reliable lesion characterization. • Abbreviated reading of fused DWIBS/T2w-images alone decreases diagnostic confidence and accuracy. • Reading fused DWIBS/T2w-images as the sole diagnostic method should be avoided.

A comparison of bivariate, multivariate random-effects, and Poisson correlated gamma-frailty models to meta-analyze individual patient data of ordinal scale diagnostic tests.

PubMed

Simoneau, Gabrielle; Levis, Brooke; Cuijpers, Pim; Ioannidis, John P A; Patten, Scott B; Shrier, Ian; Bombardier, Charles H; de Lima Osório, Flavia; Fann, Jesse R; Gjerdingen, Dwenda; Lamers, Femke; Lotrakul, Manote; Löwe, Bernd; Shaaban, Juwita; Stafford, Lesley; van Weert, Henk C P M; Whooley, Mary A; Wittkampf, Karin A; Yeung, Albert S; Thombs, Brett D; Benedetti, Andrea

2017-11-01

Individual patient data (IPD) meta-analyses are increasingly common in the literature. In the context of estimating the diagnostic accuracy of ordinal or semi-continuous scale tests, sensitivity and specificity are often reported for a given threshold or a small set of thresholds, and a meta-analysis is conducted via a bivariate approach to account for their correlation. When IPD are available, sensitivity and specificity can be pooled for every possible threshold. Our objective was to compare the bivariate approach, which can be applied separately at every threshold, to two multivariate methods: the ordinal multivariate random-effects model and the Poisson correlated gamma-frailty model. Our comparison was empirical, using IPD from 13 studies that evaluated the diagnostic accuracy of the 9-item Patient Health Questionnaire depression screening tool, and included simulations. The empirical comparison showed that the implementation of the two multivariate methods is more laborious in terms of computational time and sensitivity to user-supplied values compared to the bivariate approach. Simulations showed that ignoring the within-study correlation of sensitivity and specificity across thresholds did not worsen inferences with the bivariate approach compared to the Poisson model. The ordinal approach was not suitable for simulations because the model was highly sensitive to user-supplied starting values. We tentatively recommend the bivariate approach rather than more complex multivariate methods for IPD diagnostic accuracy meta-analyses of ordinal scale tests, although the limited type of diagnostic data considered in the simulation study restricts the generalization of our findings. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Diagnostic accuracy of 22/25-gauge core needle in endoscopic ultrasound-guided sampling: systematic review and meta-analysis.

PubMed

Oh, Hyoung-Chul; Kang, Hyun; Lee, Jae Young; Choi, Geun Joo; Choi, Jung Sik

2016-11-01

To compare the diagnostic accuracy of endoscopic ultrasound-guided core needle aspiration with that of standard fine-needle aspiration by systematic review and meta-analysis. Studies using 22/25-gauge core needles, irrespective of comparison with standard fine needles, were comprehensively reviewed. Pooled sensitivity, specificity, diagnostic odds ratio (DOR), and summary receiver operating characteristic curves for the diagnosis of malignancy were used to estimate the overall diagnostic efficiency. The pooled sensitivity, specificity, and DOR of the core needle for the diagnosis of malignancy were 0.88 (95% confidence interval [CI], 0.84 to 0.90), 0.99 (95% CI, 0.96 to 1), and 167.37 (95% CI, 65.77 to 425.91), respectively. The pooled sensitivity, specificity, and DOR of the standard needle were 0.84 (95% CI, 0.79 to 0.88), 1 (95% CI, 0.97 to 1), and 130.14 (95% CI, 34.00 to 495.35), respectively. The area under the curve of core and standard needle in the diagnosis of malignancy was 0.974 and 0.955, respectively. The core and standard needle were comparable in terms of pancreatic malignancy diagnosis. There was no significant difference in procurement of optimal histologic cores between core and standard needles (risk ratio [RR], 0.545; 95% CI, 0.187 to 1.589). The number of needle passes for diagnosis was significantly lower with the core needle (standardized mean difference, -0.72; 95% CI, -1.02 to -0.41). There were no significant differences in overall complications (RR, 1.26; 95% CI, 0.34 to 4.62) and technical failure (RR, 5.07; 95% CI, 0.68 to 37.64). Core and standard needles were comparable in terms of diagnostic accuracy, technical performance, and safety profile.

Identification of Nasal Bone Fractures on Conventional Radiography and Facial CT: Comparison of the Diagnostic Accuracy in Different Imaging Modalities and Analysis of Interobserver Reliability.

PubMed

Baek, Hye Jin; Kim, Dong Wook; Ryu, Ji Hwa; Lee, Yoo Jin

2013-09-01

There has been no study to compare the diagnostic accuracy of an experienced radiologist with a trainee in nasal bone fracture. To compare the diagnostic accuracy between conventional radiography and computed tomography (CT) for the identification of nasal bone fractures and to evaluate the interobserver reliability between a staff radiologist and a trainee. A total of 108 patients who underwent conventional radiography and CT after acute nasal trauma were included in this retrospective study. Two readers, a staff radiologist and a second-year resident, independently assessed the results of the imaging studies. Of the 108 patients, the presence of a nasal bone fracture was confirmed in 88 (81.5%) patients. The number of non-depressed fractures was higher than the number of depressed fractures. In nine (10.2%) patients, nasal bone fractures were only identified on conventional radiography, including three depressed and six non-depressed fractures. CT was more accurate as compared to conventional radiography for the identification of nasal bone fractures as determined by both readers (P <0.05), all diagnostic indices of an experienced radiologist were similar to or higher than those of a trainee, and κ statistics showed moderate agreement between the two diagnostic tools for both readers. There was no statistical difference in the assessment of interobserver reliability for both imaging modalities in the identification of nasal bone fractures. For the identification of nasal bone fractures, CT was significantly superior to conventional radiography. Although a staff radiologist showed better values in the identification of nasal bone fracture and differentiation between depressed and non-depressed fractures than a trainee, there was no statistically significant difference in the interpretation of conventional radiography and CT between a radiologist and a trainee.

An index with improved diagnostic accuracy for the diagnosis of Crohn's disease derived from the Lennard-Jones criteria.

PubMed

Reinisch, S; Schweiger, K; Pablik, E; Collet-Fenetrier, B; Peyrin-Biroulet, L; Alfaro, I; Panés, J; Moayyedi, P; Reinisch, W

2016-09-01

The Lennard-Jones criteria are considered the gold standard for diagnosing Crohn's disease (CD) and include the items granuloma, macroscopic discontinuity, transmural inflammation, fibrosis, lymphoid aggregates and discontinuous inflammation on histology. The criteria have never been subjected to a formal validation process. To develop a validated and improved diagnostic index based on the items of Lennard-Jones criteria. Included were 328 adult patients with long-standing CD (median disease duration 10 years) from three centres and classified as 'established', 'probable' or 'non-CD' by Lennard-Jones criteria at time of diagnosis. Controls were patients with ulcerative colitis (n = 170). The performance of each of the six diagnostic items of Lennard-Jones criteria was modelled by logistic regression and a new index based on stepwise backward selection and cut-offs was developed. The diagnostic value of the new index was analysed by comparing sensitivity, specificity and accuracy vs. Lennard-Jones criteria. By Lennard-Jones criteria 49% (n = 162) of CD patients would have been diagnosed as 'non-CD' at time of diagnosis (sensitivity/specificity/accuracy, 'established' CD: 0.34/0.99/0.67; 'probable' CD: 0.51/0.95/0.73). A new index was derived from granuloma, fibrosis, transmural inflammation and macroscopic discontinuity, but excluded lymphoid aggregates and discontinuous inflammation on histology. Our index provided improved diagnostic accuracy for 'established' and 'probable' CD (sensitivity/specificity/accuracy, 'established' CD: 0.45/1/0.72; 'probable' CD: 0.8/0.85/0.82), including the subgroup isolated colonic CD ('probable' CD, new index: 0.73/0.85/0.79; Lennard-Jones criteria: 0.43/0.95/0.69). We developed an index based on items of Lennard-Jones criteria providing improved diagnostic accuracy for the differential diagnosis between CD and UC. © 2016 John Wiley & Sons Ltd.

Enhanced CT images by the wavelet transform improving diagnostic accuracy of chest nodules.

PubMed

Guo, Xiuhua; Liu, Xiangye; Wang, Huan; Liang, Zhigang; Wu, Wei; He, Qian; Li, Kuncheng; Wang, Wei

2011-02-01

The objective of this study was to compare the diagnostic accuracy in the interpretation of chest nodules using original CT images versus enhanced CT images based on the wavelet transform. The CT images of 118 patients with cancers and 60 with benign nodules were used in this study. All images were enhanced through an algorithm based on the wavelet transform. Two experienced radiologists interpreted all the images in two reading sessions. The reading sessions were separated by a minimum of 1 month in order to minimize the effect of observer's recall. The Mann-Whitney U nonparametric test was used to analyze the interpretation results between original and enhanced images. The Kruskal-Wallis H nonparametric test of K independent samples was used to investigate the related factors which could affect the diagnostic accuracy of observers. The area under the ROC curves for the original and enhanced images was 0.681 and 0.736, respectively. There is significant difference in diagnosing the malignant nodules between the original and enhanced images (z = 7.122, P < 0.001), whereas there is no significant difference in diagnosing the benign nodules (z = 0.894, P = 0.371). The results showed that there is significant difference between original and enhancement images when the size of nodules was larger than 2 cm (Z = -2.509, P = 0.012, indicating the size of the nodules is a critical evaluating factor of the diagnostic accuracy of observers). This study indicated that the image enhancement based on wavelet transform could improve the diagnostic accuracy of radiologists for the malignant chest nodules.

Non-invasive diagnosis of acute rejection in renal transplant patients using mass spectrometry of urine samples - a multicentre phase 3 diagnostic accuracy study.

PubMed

Zapf, Antonia; Gwinner, Wilfried; Karch, Annika; Metzger, Jochen; Haller, Hermann; Koch, Armin

2015-09-15

Reliable and timely detection of acute rejection in renal transplant patients is important to preserve the allograft function and to prevent premature allograft failure. The current gold standard for the rejection diagnosis is an allograft biopsy which is usually performed upon an unexplained decline in allograft function. Because of the invasiveness of the biopsy, non-invasive tests have been suggested to diagnose acute rejection including mass spectrometry analysis of urine samples. The aim of this study is to examine the diagnostic accuracy of mass spectrometry analysis in urine for the diagnosis of acute rejections using the biopsy as gold-standard. The study is an ongoing prospective, single-arm, multicentre, phase 3 diagnostic accuracy study. It started in October 2011 and will be concluded in December 2015. Patient within the first year after transplantation who are scheduled for a biopsy to clarify unexplained impairment of the allograft are consecutively recruited into the study. The overall sample size (n = 600) was calculated to demonstrate a sensitivity of 83 % and a specificity of 70 % for a one-sided type one error of 2.5 % and a power of 80 % per hypothesis. Biopsy evaluation and mass spectrometry analysis of urine samples (obtained immediately before biopsy) are performed independently by different readers without knowledge from the respective other assessment. The follow-up observation period is 6 months. For the primary analysis, the lower limits of the two-sided 95 % Wald confidence intervals for sensitivity and specificity will be compared with the pre-specified thresholds (83 % for sensitivity and 70 % for specificity). In secondary analyses the predictive values, the diagnostic measures in subgroups, and the clinical course will be assessed. Previous phase 2 diagnostic accuracy studies (in small selected study populations) provided sufficient evidence to suggest mass spectrometry on urine samples as a promising approach to detect acute rejections. This study determines the diagnostic performance of the test in the routine setting of post-transplant patient care, compared to the biopsy-based rejection diagnosis. The next step would be a randomized trial to compare the two diagnostic strategies (including the urine test or not) in relation to patient relevant endpoints. NCT01315067 ; March 14, 2011.

Effects of disease severity distribution on the performance of quantitative diagnostic methods and proposal of a novel ‘V-plot’ methodology to display accuracy values

PubMed Central

Dehbi, Hakim-Moulay; Howard, James P; Shun-Shin, Matthew J; Sen, Sayan; Nijjer, Sukhjinder S; Mayet, Jamil; Davies, Justin E; Francis, Darrel P

2018-01-01

Background Diagnostic accuracy is widely accepted by researchers and clinicians as an optimal expression of a test’s performance. The aim of this study was to evaluate the effects of disease severity distribution on values of diagnostic accuracy as well as propose a sample-independent methodology to calculate and display accuracy of diagnostic tests. Methods and findings We evaluated the diagnostic relationship between two hypothetical methods to measure serum cholesterol (Cholrapid and Cholgold) by generating samples with statistical software and (1) keeping the numerical relationship between methods unchanged and (2) changing the distribution of cholesterol values. Metrics of categorical agreement were calculated (accuracy, sensitivity and specificity). Finally, a novel methodology to display and calculate accuracy values was presented (the V-plot of accuracies). Conclusion No single value of diagnostic accuracy can be used to describe the relationship between tests, as accuracy is a metric heavily affected by the underlying sample distribution. Our novel proposed methodology, the V-plot of accuracies, can be used as a sample-independent measure of a test performance against a reference gold standard. PMID:29387424

Selective parathyroid venous sampling in primary hyperparathyroidism: A systematic review and meta-analysis.

PubMed

Ibraheem, Kareem; Toraih, Eman A; Haddad, Antoine B; Farag, Mahmoud; Randolph, Gregory W; Kandil, Emad

2018-05-14

Minimally invasive parathyroidectomy requires accurate preoperative localization techniques. There is considerable controversy about the effectiveness of selective parathyroid venous sampling (sPVS) in primary hyperparathyroidism (PHPT) patients. The aim of this meta-analysis is to examine the diagnostic accuracy of sPVS as a preoperative localization modality in PHPT. Studies evaluating the diagnostic accuracy of sPVS for PHPT were electronically searched in the PubMed, EMBASE, Web of Science, and Cochrane Controlled Trials Register databases. Two independent authors reviewed the studies, and revised quality assessment of diagnostic accuracy study tool was used for the quality assessment. Study heterogeneity and pooled estimates were calculated. Two hundred and two unique studies were identified. Of those, 12 studies were included in the meta-analysis. Pooled sensitivity, specificity, and positive likelihood ratio (PLR) of sPVS were 74%, 41%, and 1.55, respectively. The area-under-the-receiver operating characteristic curve was 0.684, indicating an average discriminatory ability of sPVS. On comparison between sPVS and noninvasive imaging modalities, sensitivity, PLR, and positive posttest probability were significantly higher in sPVS compared to noninvasive imaging modalities. Interestingly, super-selective venous sampling had the highest sensitivity, accuracy, and positive posttest probability compared to other parathyroid venous sampling techniques. This is the first meta-analysis to examine the accuracy of sPVS in PHPT. sPVS had higher pooled sensitivity when compared to noninvasive modalities in revision parathyroid surgery. However, the invasiveness of this technique does not favor its routine use for preoperative localization. Super-selective venous sampling was the most accurate among all other parathyroid venous sampling techniques. Laryngoscope, 2018. © 2018 The American Laryngological, Rhinological and Otological Society, Inc.

Diagnostic accuracy of tuberculous lymphadenitis fine needle aspiration biopsy confirmed by PCR as gold standard

NASA Astrophysics Data System (ADS)

DSuryadi; Delyuzar; Soekimin

2018-03-01

Indonesia is the second country with the TB (tuberculosis) burden in the world. Improvement in controlling TB and reducing the complications can accelerate early diagnosis and correct treatment. PCR test is a gold standard. However, it is quite expensive for routine diagnosis. Therefore, an accurate and cheaper diagnostic method such as fine needle aspiration biopsy is needed. The study aimsto determine the accuracy of fine needle aspiration biopsy cytology in the diagnosis of tuberculous lymphadenitis. A cross-sectional analytic study was conducted to the samples from patients suspected with tuberculous lymphadenitis. The fine needle aspiration biopsy (FNAB)test was performed and confirmed by PCR test.There is a comparison to the sensitivity, specificity, accuracy, positive predictive value and negative predictive value of both methods. Sensitivity (92.50%), specificity (96.49%), accuracy (94.85%), positive predictive value (94.87%) and negative predictive value (94.83%) were in FNAB test compared to gold standard. We concluded that fine needle aspiration biopsy is a recommendation for a cheaper and accurate diagnostic test for tuberculous lymphadenitis diagnosis.

The effects of divided attention at study and reporting procedure on regulation and monitoring for episodic recall.

PubMed

Sauer, James; Hope, Lorraine

2016-09-01

Eyewitnesses regulate the level of detail (grain size) reported to balance competing demands for informativeness and accuracy. However, research to date has predominantly examined metacognitive monitoring for semantic memory tasks, and used relatively artificial phased reporting procedures. Further, although the established role of confidence in this regulation process may affect the confidence-accuracy relation for volunteered responses in predictable ways, previous investigations of the confidence-accuracy relation for eyewitness recall have largely overlooked the regulation of response granularity. Using a non-phased paradigm, Experiment 1 compared reporting and monitoring following optimal and sub-optimal (divided attention) encoding conditions. Participants showed evidence of sacrificing accuracy for informativeness, even when memory quality was relatively weak. Participants in the divided (cf. full) attention condition showed reduced accuracy for fine- but not coarse-grained responses. However, indices of discrimination and confidence diagnosticity showed no effect of divided attention. Experiment 2 compared the effects of divided attention at encoding on reporting and monitoring using both non-phased and 2-phase procedures. Divided attention effects were consistent with Experiment 1. However, compared to those in the non-phased condition, participants in the 2-phase condition displayed a more conservative control strategy, and confidence ratings were less diagnostic of accuracy. When memory quality was reduced, although attempts to balance informativeness and accuracy increased the chance of fine-grained response errors, confidence provided an index of the likely accuracy of volunteered fine-grained responses for both condition. Copyright © 2016 Elsevier B.V. All rights reserved.

The Effects of Q-Matrix Design on Classification Accuracy in the Log-Linear Cognitive Diagnosis Model

ERIC Educational Resources Information Center

Madison, Matthew J.; Bradshaw, Laine P.

2015-01-01

Diagnostic classification models are psychometric models that aim to classify examinees according to their mastery or non-mastery of specified latent characteristics. These models are well-suited for providing diagnostic feedback on educational assessments because of their practical efficiency and increased reliability when compared with other…

Displaying chest X-ray by beamer or monitor: comparison of diagnostic accuracy for subtle abnormalities.

PubMed

Kuiper, L M; Thijs, A; Smulders, Y M

2012-01-01

The advent of beamer projection of radiological images raises the issue of whether such projection compromises diagnostic accuracy. The purpose of this study was to evaluate whether beamer projection of chest X-rays is inferior to monitor display. We selected 53 chest X-rays with subtle abnormalities and 15 normal X-rays. The images were independently judged by a senior radiologist and a senior pulmonologist with a state-of-art computer monitor. We used their unanimous or consensus judgment as the reference test. Subsequently, four observers (one senior pulmonologist, one senior radiologist and one resident from each speciality) judged these X-rays on a standard clinical computer monitor and with beamer projection. We compared the number of correct results for each method. Overall, the sensitivity and specificity did not differ between monitor and beamer projection. Separate analyses in senior and junior examiners suggested that senior examiners had a moderate loss of diagnostic accuracy (8% lower sensitivity, pp<0.05, and 6% lower specificity, p=ns) associated with the use of beamer projection, whereas juniors showed similar performance on both imaging modalities. These initial data suggest that beamer projection may be associated with a small loss of diagnostic accuracy in specific subgroups of physicians. This finding illustrates the need for more extensive studies.

Proximal pulmonary vein stenosis detection in pediatric patients: value of multiplanar and 3-D VR imaging evaluation.

PubMed

Lee, Edward Y; Jenkins, Kathy J; Muneeb, Muhammad; Marshall, Audrey C; Tracy, Donald A; Zurakowski, David; Boiselle, Phillip M

2013-08-01

One of the important benefits of using multidetector computed tomography (MDCT) is its capability to generate high-quality two-dimensional (2-D) multiplanar (MPR) and three-dimensional (3-D) images from volumetric and isotropic axial CT data. However, to the best of our knowledge, no results have been published on the potential diagnostic role of multiplanar and 3-D volume-rendered (VR) images in detecting pulmonary vein stenosis, a condition in which MDCT has recently assumed a role as the initial noninvasive imaging modality of choice. The purpose of this study was to compare diagnostic accuracy and interpretation time of axial, multiplanar and 3-D VR images for detection of proximal pulmonary vein stenosis in children, and to assess the potential added diagnostic value of multiplanar and 3-D VR images. We used our hospital information system to identify all consecutive children (< 18 years of age) with proximal pulmonary vein stenosis who had both a thoracic MDCT angiography study and a catheter-based conventional angiography within 2 months from June 2005 to February 2012. Two experienced pediatric radiologists independently reviewed each MDCT study for the presence of proximal pulmonary vein stenosis defined as ≥ 50% of luminal narrowing on axial, multiplanar and 3-D VR images. Final diagnosis was confirmed by angiographic findings. Diagnostic accuracy was compared using the z-test. Confidence level of diagnosis (scale 1-5, 5 = highest), perceived added diagnostic value (scale 1-5, 5 = highest), and interpretation time of multiplanar or 3-D VR images were compared using paired t-tests. Interobserver agreement was measured using the chance-corrected kappa coefficient. The final study population consisted of 28 children (15 boys and 13 girls; mean age: 5.2 months). Diagnostic accuracy based on 116 individual pulmonary veins for detection of proximal pulmonary vein stenosis was 72.4% (84 of 116) for axial MDCT images, 77.5% (90 of 116 cases) for multiplanar MDCT images, and 93% (108 of 116 cases) for 3-D VR images with significantly higher accuracy with 3-D VR compared to axial (z = 4.17, P < 0.001) and multiplanar (z = 3.34, P < 0.001) images. Confidence levels for detection of proximal pulmonary vein stenosis were significantly higher with 3-D VR images (mean level: 4.6) compared to axial MDCT images (mean level: 1.7) and multiplanar MDCT images (mean level: 2.0) (paired t-tests, P < 0.001). Thus, 3-D VR images (mean added diagnostic value: 4.7) were found to provide added diagnostic value for detecting proximal pulmonary vein stenosis (paired t-test, P < 0.001); however, multiplanar MDCT images did not provide added value (paired t-test, P = 0.89). Interpretation time was significantly longer and interobserver agreement was higher when using 3-D VR images than using axial MDCT images or MPR MDCT images for diagnosing proximal pulmonary vein stenosis (paired t-tests, P < 0.001). Use of 3-D VR images in the diagnosis of proximal pulmonary vein stenosis in children significantly increases accuracy, confidence level, added diagnostic value and interobserver agreement. Thus, the routine use of this technique should be encouraged despite its increased interpretation time.

Accuracy of the Canadian C-spine rule and NEXUS to screen for clinically important cervical spine injury in patients following blunt trauma: a systematic review

PubMed Central

Michaleff, Zoe A.; Maher, Chris G.; Verhagen, Arianne P.; Rebbeck, Trudy; Lin, Chung-Wei Christine

2012-01-01

Background: There is uncertainty about the optimal approach to screen for clinically important cervical spine (C-spine) injury following blunt trauma. We conducted a systematic review to investigate the diagnostic accuracy of the Canadian C-spine rule and the National Emergency X-Radiography Utilization Study (NEXUS) criteria, 2 rules that are available to assist emergency physicians to assess the need for cervical spine imaging. Methods: We identified studies by an electronic search of CINAHL, Embase and MEDLINE. We included articles that reported on a cohort of patients who experienced blunt trauma and for whom clinically important cervical spine injury detectable by diagnostic imaging was the differential diagnosis; evaluated the diagnostic accuracy of the Canadian C-spine rule or NEXUS or both; and used an adequate reference standard. We assessed the methodologic quality using the Quality Assessment of Diagnostic Accuracy Studies criteria. We used the extracted data to calculate sensitivity, specificity, likelihood ratios and post-test probabilities. Results: We included 15 studies of modest methodologic quality. For the Canadian C-spine rule, sensitivity ranged from 0.90 to 1.00 and specificity ranged from 0.01 to 0.77. For NEXUS, sensitivity ranged from 0.83 to 1.00 and specificity ranged from 0.02 to 0.46. One study directly compared the accuracy of these 2 rules using the same cohort and found that the Canadian C-spine rule had better accuracy. For both rules, a negative test was more informative for reducing the probability of a clinically important cervical spine injury. Interpretation: Based on studies with modest methodologic quality and only one direct comparison, we found that the Canadian C-spine rule appears to have better diagnostic accuracy than the NEXUS criteria. Future studies need to follow rigorous methodologic procedures to ensure that the findings are as free of bias as possible. PMID:23048086

Evaluating the diagnostic accuracy of the Xpert MTB/RIF assay on bronchoalveolar lavage fluid: A retrospective study.

PubMed

Lu, Yanjun; Zhu, Yaowu; Shen, Na; Tian, Lei; Sun, Ziyong

2018-02-08

Limited data on the diagnostic accuracy of the Xpert MTB/RIF assay using bronchoalveolar lavage fluid from patients with suspected pulmonary tuberculosis (PTB) have been reported in China. Therefore, a retrospective study was designed to evaluate the diagnostic accuracy of this assay. Clinical, radiological, and microbiological characteristics of 238 patients with suspected PTB were reviewed retrospectively. The sensitivity, specificity, positive predictive value, and negative predictive value for the diagnosis of active PTB were calculated for the Xpert MTB/RIF assay using TB culture or final diagnosis based on clinical and radiological evaluation as the reference standard. The sensitivity and specificity of the Xpert MTB/RIF assay were 84.5% and 98.9%, respectively, and those for smear microscopy were 36.2% and 100%, respectively, when compared to the culture method. However, compared with the sensitivity and specificity of final diagnosis based on clinical and radiological evaluation, the sensitivity and specificity of the assay were 72.9% and 98.7%, respectively, which were significantly higher than those for smear microscopy. The Xpert MTB/RIF assay on bronchoalveolar lavage fluid could serve as an additional rapid diagnostic tool for PTB in a high TB-burden country and improve the time to TB treatment initiation in patients with PTB. Copyright © 2018 The Author(s). Published by Elsevier Ltd.. All rights reserved.

Methodological quality of diagnostic accuracy studies on non-invasive coronary CT angiography: influence of QUADAS (Quality Assessment of Diagnostic Accuracy Studies included in systematic reviews) items on sensitivity and specificity.

PubMed

Schueler, Sabine; Walther, Stefan; Schuetz, Georg M; Schlattmann, Peter; Dewey, Marc

2013-06-01

To evaluate the methodological quality of diagnostic accuracy studies on coronary computed tomography (CT) angiography using the QUADAS (Quality Assessment of Diagnostic Accuracy Studies included in systematic reviews) tool. Each QUADAS item was individually defined to adapt it to the special requirements of studies on coronary CT angiography. Two independent investigators analysed 118 studies using 12 QUADAS items. Meta-regression and pooled analyses were performed to identify possible effects of methodological quality items on estimates of diagnostic accuracy. The overall methodological quality of coronary CT studies was merely moderate. They fulfilled a median of 7.5 out of 12 items. Only 9 of the 118 studies fulfilled more than 75 % of possible QUADAS items. One QUADAS item ("Uninterpretable Results") showed a significant influence (P = 0.02) on estimates of diagnostic accuracy with "no fulfilment" increasing specificity from 86 to 90 %. Furthermore, pooled analysis revealed that each QUADAS item that is not fulfilled has the potential to change estimates of diagnostic accuracy. The methodological quality of studies investigating the diagnostic accuracy of non-invasive coronary CT is only moderate and was found to affect the sensitivity and specificity. An improvement is highly desirable because good methodology is crucial for adequately assessing imaging technologies. • Good methodological quality is a basic requirement in diagnostic accuracy studies. • Most coronary CT angiography studies have only been of moderate design quality. • Weak methodological quality will affect the sensitivity and specificity. • No improvement in methodological quality was observed over time. • Authors should consider the QUADAS checklist when undertaking accuracy studies.

Systematic review of proposed definitions of nocturnal polyuria and population-based evidence of their diagnostic accuracy.

PubMed

Olesen, Tine Kold; Denys, Marie-Astrid; Vande Walle, Johan; Everaert, Karel

2018-02-06

Background Evidence of diagnostic accuracy for proposed definitions of nocturnal polyuria is currently unclear. Purpose Systematic review to determine population-based evidence of the diagnostic accuracy of proposed definitions of nocturnal polyuria based on data from frequency-volume charts. Methods Seventeen pre-specified search terms identified 351 unique investigations published from 1990 to 2016 in BIOSIS, Embase, Embase Alerts, International Pharmaceutical Abstract, Medline, and Cochrane. Thirteen original communications were included in this review based on pre-specified exclusion criteria. Data were extracted from each paper regarding subject age, sex, ethnicity, health status, sample size, data collection methods, and diagnostic discrimination of proposed definitions including sensitivity, specificity, positive and negative predictive value. Results The sample size of study cohorts, participant age, sex, ethnicity, and health status varied considerably in 13 studies reporting on the diagnostic performance of seven different definitions of nocturnal polyuria using frequency-volume chart data from 4968 participants. Most study cohorts were small, mono-ethnic, including only Caucasian males aged 50 or higher with primary or secondary polyuria that were compared to a control group of healthy men without nocturia in prospective or retrospective settings. Proposed definitions had poor discriminatory accuracy in evaluations based on data from subjects independent from the original study cohorts with findings being similar regarding the most widely evaluated definition endorsed by ICS. Conclusions Diagnostic performance characteristics for proposed definitions of nocturnal polyuria show poor to modest discrimination and are not based on sufficient level of evidence from representative, multi-ethnic population-based data from both females and males of all adult ages.

The accuracy and cost-effectiveness of strategies used to identify peripheral artery disease among patients with diabetic foot ulcers.

PubMed

Barshes, Neal R; Flores, Everardo; Belkin, Michael; Kougias, Panos; Armstrong, David G; Mills, Joseph L

2016-12-01

Patients with diabetic foot ulcers (DFUs) should be evaluated for peripheral artery disease (PAD). We sought to estimate the overall diagnostic accuracy for various strategies that are used to identify PAD in this population. A Markov model with probabilistic and deterministic sensitivity analyses was used to simulate the clinical events in a population of 10,000 patients with diabetes. One of 14 different diagnostic strategies was applied to those who developed DFUs. Baseline data on diagnostic accuracy of individual noninvasive tests were based on a meta-analysis of previously reported studies. The overall sensitivity and cost-effectiveness of the 14 strategies were then compared. The overall sensitivity of various combinations of diagnostic testing strategies ranged from 32.6% to 92.6%. Cost-effective strategies included ankle-brachial indices for all patients; skin perfusion pressures (SPPs) or toe-brachial indices (TBIs) for all patients; and SPPs or TBIs to corroborate normal pulse examination findings, a strategy that lowered leg amputation rates by 36%. Strategies that used noninvasive vascular testing to investigate only abnormal pulse examination results had low overall diagnostic sensitivity and were weakly dominated in cost-effectiveness evaluations. Population prevalence of PAD did not alter strategy ordering by diagnostic accuracy or cost-effectiveness. TBIs or SPPs used uniformly or to corroborate a normal pulse examination finding are among the most sensitive and cost-effective strategies to improve the identification of PAD among patients presenting with DFUs. These strategies may significantly reduce leg amputation rates with only modest increases in cost. Published by Elsevier Inc.

Accuracy and precision of four value-added blood glucose meters: the Abbott Optium, the DDI Prodigy, the HDI True Track, and the HypoGuard Assure Pro.

PubMed

Sheffield, Catherine A; Kane, Michael P; Bakst, Gary; Busch, Robert S; Abelseth, Jill M; Hamilton, Robert A

2009-09-01

This study compared the accuracy and precision of four value-added glucose meters. Finger stick glucose measurements in diabetes patients were performed using the Abbott Diabetes Care (Alameda, CA) Optium, Diagnostic Devices, Inc. (Miami, FL) DDI Prodigy, Home Diagnostics, Inc. (Fort Lauderdale, FL) HDI True Track Smart System, and Arkray, USA (Minneapolis, MN) HypoGuard Assure Pro. Finger glucose measurements were compared with laboratory reference results. Accuracy was assessed by a Clarke error grid analysis (EGA), a Parkes EGA, and within 5%, 10%, 15%, and 20% of the laboratory value criteria (chi2 analysis). Meter precision was determined by calculating absolute mean differences in glucose values between duplicate samples (Kruskal-Wallis test). Finger sticks were obtained from 125 diabetes patients, of which 90.4% were Caucasian, 51.2% were female, 83.2% had type 2 diabetes, and average age of 59 years (SD 14 years). Mean venipuncture blood glucose was 151 mg/dL (SD +/-65 mg/dL; range, 58-474 mg/dL). Clinical accuracy by Clarke EGA was demonstrated in 94% of Optium, 82% of Prodigy, 61% of True Track, and 77% of the Assure Pro samples (P < 0.05 for Optium and True Track compared to all others). By Parkes EGA, the True Track was significantly less accurate than the other meters. Within 5% accuracy was achieved in 34%, 24%, 29%, and 13%, respectively (P < 0.05 for Optium, Prodigy, and Assure Pro compared to True Track). Within 10% accuracy was significantly greater for the Optium, Prodigy, and Assure Pro compared to True Track. Significantly more Optium results demonstrated within 15% and 20% accuracy compared to the other meter systems. The HDI True Track was significantly less precise than the other meter systems. The Abbott Optium was significantly more accurate than the other meter systems, whereas the HDI True Track was significantly less accurate and less precise compared to the other meter systems.

Network meta-analysis of diagnostic test accuracy studies identifies and ranks the optimal diagnostic tests and thresholds for health care policy and decision-making.

PubMed

Owen, Rhiannon K; Cooper, Nicola J; Quinn, Terence J; Lees, Rosalind; Sutton, Alex J

2018-07-01

Network meta-analyses (NMA) have extensively been used to compare the effectiveness of multiple interventions for health care policy and decision-making. However, methods for evaluating the performance of multiple diagnostic tests are less established. In a decision-making context, we are often interested in comparing and ranking the performance of multiple diagnostic tests, at varying levels of test thresholds, in one simultaneous analysis. Motivated by an example of cognitive impairment diagnosis following stroke, we synthesized data from 13 studies assessing the efficiency of two diagnostic tests: Mini-Mental State Examination (MMSE) and Montreal Cognitive Assessment (MoCA), at two test thresholds: MMSE <25/30 and <27/30, and MoCA <22/30 and <26/30. Using Markov chain Monte Carlo (MCMC) methods, we fitted a bivariate network meta-analysis model incorporating constraints on increasing test threshold, and accounting for the correlations between multiple test accuracy measures from the same study. We developed and successfully fitted a model comparing multiple tests/threshold combinations while imposing threshold constraints. Using this model, we found that MoCA at threshold <26/30 appeared to have the best true positive rate, whereas MMSE at threshold <25/30 appeared to have the best true negative rate. The combined analysis of multiple tests at multiple thresholds allowed for more rigorous comparisons between competing diagnostics tests for decision making. Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.

The Hospital Anxiety and Depression Scale (HADS) and the 9-item Patient Health Questionnaire (PHQ-9) as screening instruments for depression in patients with cancer.

PubMed

Hartung, Tim J; Friedrich, Michael; Johansen, Christoffer; Wittchen, Hans-Ulrich; Faller, Herman; Koch, Uwe; Brähler, Elmar; Härter, Martin; Keller, Monika; Schulz, Holger; Wegscheider, Karl; Weis, Joachim; Mehnert, Anja

2017-11-01

Depression screening in patients with cancer is recommended by major clinical guidelines, although the evidence on individual screening tools is limited for this population. Here, the authors assess and compare the diagnostic accuracy of 2 established screening instruments: the depression modules of the 9-item Patient Health Questionnaire (PHQ-9) and the Hospital Anxiety and Depression Scale (HADS-D), in a representative sample of patients with cancer. This multicenter study was conducted with a proportional, stratified, random sample of 2141 patients with cancer across all major tumor sites and treatment settings. The PHQ-9 and HADS-D were assessed and compared in terms of diagnostic accuracy and receiver operating characteristic (ROC) curves for Diagnostic and Statistical Manual of Mental Disorders, 4th edition diagnosis of major depressive disorder using the Composite International Diagnostic Interview for Oncology as the criterion standard. The diagnostic accuracy of the PHQ-9 and HADS-D was fair for diagnosing major depressive disorder, with areas under the ROC curves of 0.78 (95% confidence interval, 0.76-0.79) and 0.75 (95% confidence interval, 0.74-0.77), respectively. The 2 questionnaires did not differ significantly in their areas under the ROC curves (P = .15). The PHQ-9 with a cutoff score ≥7 had the best screening performance, with a sensitivity of 83% (95% confidence interval, 78%-89%) and a specificity of 61% (95% confidence interval, 59%-63%). The American Society of Clinical Oncology guideline screening algorithm had a sensitivity of 44% (95% confidence interval, 36%-51%) and a specificity of 84% (95% confidence interval, 83%-85%). In patients with cancer, the screening performance of both the PHQ-9 and the HADS-D was limited compared with a standardized diagnostic interview. Costs and benefits of routinely screening all patients with cancer should be weighed carefully. Cancer 2017;123:4236-4243. © 2017 American Cancer Society. © 2017 American Cancer Society.

Rapid detection of health-care-associated bloodstream infection in critical care using multipathogen real-time polymerase chain reaction technology: a diagnostic accuracy study and systematic review.

PubMed

Warhurst, Geoffrey; Dunn, Graham; Chadwick, Paul; Blackwood, Bronagh; McAuley, Daniel; Perkins, Gavin D; McMullan, Ronan; Gates, Simon; Bentley, Andrew; Young, Duncan; Carlson, Gordon L; Dark, Paul

2015-05-01

There is growing interest in the potential utility of real-time polymerase chain reaction (PCR) in diagnosing bloodstream infection by detecting pathogen deoxyribonucleic acid (DNA) in blood samples within a few hours. SeptiFast (Roche Diagnostics GmBH, Mannheim, Germany) is a multipathogen probe-based system targeting ribosomal DNA sequences of bacteria and fungi. It detects and identifies the commonest pathogens causing bloodstream infection. As background to this study, we report a systematic review of Phase III diagnostic accuracy studies of SeptiFast, which reveals uncertainty about its likely clinical utility based on widespread evidence of deficiencies in study design and reporting with a high risk of bias. Determine the accuracy of SeptiFast real-time PCR for the detection of health-care-associated bloodstream infection, against standard microbiological culture. Prospective multicentre Phase III clinical diagnostic accuracy study using the standards for the reporting of diagnostic accuracy studies criteria. Critical care departments within NHS hospitals in the north-west of England. Adult patients requiring blood culture (BC) when developing new signs of systemic inflammation. SeptiFast real-time PCR results at species/genus level compared with microbiological culture in association with independent adjudication of infection. Metrics of diagnostic accuracy were derived including sensitivity, specificity, likelihood ratios and predictive values, with their 95% confidence intervals (CIs). Latent class analysis was used to explore the diagnostic performance of culture as a reference standard. Of 1006 new patient episodes of systemic inflammation in 853 patients, 922 (92%) met the inclusion criteria and provided sufficient information for analysis. Index test assay failure occurred on 69 (7%) occasions. Adult patients had been exposed to a median of 8 days (interquartile range 4-16 days) of hospital care, had high levels of organ support activities and recent antibiotic exposure. SeptiFast real-time PCR, when compared with culture-proven bloodstream infection at species/genus level, had better specificity (85.8%, 95% CI 83.3% to 88.1%) than sensitivity (50%, 95% CI 39.1% to 60.8%). When compared with pooled diagnostic metrics derived from our systematic review, our clinical study revealed lower test accuracy of SeptiFast real-time PCR, mainly as a result of low diagnostic sensitivity. There was a low prevalence of BC-proven pathogens in these patients (9.2%, 95% CI 7.4% to 11.2%) such that the post-test probabilities of both a positive (26.3%, 95% CI 19.8% to 33.7%) and a negative SeptiFast test (5.6%, 95% CI 4.1% to 7.4%) indicate the potential limitations of this technology in the diagnosis of bloodstream infection. However, latent class analysis indicates that BC has a low sensitivity, questioning its relevance as a reference test in this setting. Using this analysis approach, the sensitivity of the SeptiFast test was low but also appeared significantly better than BC. Blood samples identified as positive by either culture or SeptiFast real-time PCR were associated with a high probability (> 95%) of infection, indicating higher diagnostic rule-in utility than was apparent using conventional analyses of diagnostic accuracy. SeptiFast real-time PCR on blood samples may have rapid rule-in utility for the diagnosis of health-care-associated bloodstream infection but the lack of sensitivity is a significant limiting factor. Innovations aimed at improved diagnostic sensitivity of real-time PCR in this setting are urgently required. Future work recommendations include technology developments to improve the efficiency of pathogen DNA extraction and the capacity to detect a much broader range of pathogens and drug resistance genes and the application of new statistical approaches able to more reliably assess test performance in situation where the reference standard (e.g. blood culture in the setting of high antimicrobial use) is prone to error. The systematic review is registered as PROSPERO CRD42011001289. The National Institute for Health Research Health Technology Assessment programme. Professor Daniel McAuley and Professor Gavin D Perkins contributed to the systematic review through their funded roles as codirectors of the Intensive Care Foundation (UK).

Clinical decision making using teleradiology in urology.

PubMed

Lee, B R; Allaf, M; Moore, R; Bohlman, M; Wang, G M; Bishoff, J T; Jackman, S V; Cadeddu, J A; Jarrett, T W; Khazan, R; Kavoussi, L R

1999-01-01

Using a personal computer-based teleradiology system, we compared accuracy, confidence, and diagnostic ability in the interpretation of digitized radiographs to determine if teleradiology-imported studies convey sufficient information to make relevant clinical decisions involving urology. Variables of diagnostic accuracy, confidence, image quality, interpretation, and the impact of clinical decisions made after viewing digitized radiographs were compared with those of original radiographs. We evaluated 956 radiographs that included 94 IV pyelograms, four voiding cystourethrograms, and two nephrostograms. The radiographs were digitized and transferred over an Ethernet network to a remote personal computer-based viewing station. The digitized images were viewed by urologists and graded according to confidence in making a diagnosis, image quality, diagnostic difficulty, clinical management based on the image itself, and brief patient history. The hard-copy radiographs were then interpreted immediately afterward, and diagnostic decisions were reassessed. All analog radiographs were reviewed by an attending radiologist. Ninety-seven percent of the decisions made from the digitized radiographs did not change after reviewing conventional radiographs of the same case. When comparing the variables of clinical confidence, quality of the film on the teleradiology system versus analog films, and diagnostic difficulty, we found no statistical difference (p > .05) between the two techniques. Overall accuracy in interpreting the digitized images on the teleradiology system was 88% by urologists compared with that of the attending radiologist's interpretation of the analog radiographs. However, urologists detected findings on five (5%) analog radiographs that had been previously unreported by the radiologist. Viewing radiographs transmitted to a personal computer-based viewing station is an appropriate means of reviewing films with sufficient quality on which to base clinical decisions. Our focus was whether decisions made after viewing the transmitted radiographs would change after viewing the hard-copy images of the same case. In 97% of the cases, the decision did not change. In those cases in which management was altered, recommendation of further imaging studies was the most common factor.

How to conduct a high-quality original study on a diagnostic research topic.

PubMed

Yao, Xiaomei; Vella, Emily

2017-09-01

As health research methodologists and journal reviewers, we noticed that the methodological rigor of many publications on diagnostic or prognostic topics in the medical literature could be improved. We present a concise and clear series of reviews to help clinicians and health researchers to master the basic key components of how to conduct a high-quality original study or systematic review on a diagnostic or prognostic research topic from a methodological perspective. This is the first review of the series, which focuses on how to conduct a high-quality diagnostic study. We are introducing four aspects: clarifying the objectives; generating an appropriate research question; planning the study design; and reporting and analyzing data. This review highlights that diagnostic test accuracy outcomes are surrogates for patient outcomes, a diagnostic test has three roles, the "PIRO" components should be included in a diagnostic research question, a new study should be registered, multiple index tests can be compared in one study, and prevalence affects test accuracy outcomes. This review also emphasizes reporting any thresholds, calculating sample size, and performing a two-by-three table to calculate diagnostic outcomes. Copyright © 2017 Elsevier Ltd. All rights reserved.

CSE database: extended annotations and new recommendations for ECG software testing.

PubMed

Smíšek, Radovan; Maršánová, Lucie; Němcová, Andrea; Vítek, Martin; Kozumplík, Jiří; Nováková, Marie

2017-08-01

Nowadays, cardiovascular diseases represent the most common cause of death in western countries. Among various examination techniques, electrocardiography (ECG) is still a highly valuable tool used for the diagnosis of many cardiovascular disorders. In order to diagnose a person based on ECG, cardiologists can use automatic diagnostic algorithms. Research in this area is still necessary. In order to compare various algorithms correctly, it is necessary to test them on standard annotated databases, such as the Common Standards for Quantitative Electrocardiography (CSE) database. According to Scopus, the CSE database is the second most cited standard database. There were two main objectives in this work. First, new diagnoses were added to the CSE database, which extended its original annotations. Second, new recommendations for diagnostic software quality estimation were established. The ECG recordings were diagnosed by five new cardiologists independently, and in total, 59 different diagnoses were found. Such a large number of diagnoses is unique, even in terms of standard databases. Based on the cardiologists' diagnoses, a four-round consensus (4R consensus) was established. Such a 4R consensus means a correct final diagnosis, which should ideally be the output of any tested classification software. The accuracy of the cardiologists' diagnoses compared with the 4R consensus was the basis for the establishment of accuracy recommendations. The accuracy was determined in terms of sensitivity = 79.20-86.81%, positive predictive value = 79.10-87.11%, and the Jaccard coefficient = 72.21-81.14%, respectively. Within these ranges, the accuracy of the software is comparable with the accuracy of cardiologists. The accuracy quantification of the correct classification is unique. Diagnostic software developers can objectively evaluate the success of their algorithm and promote its further development. The annotations and recommendations proposed in this work will allow for faster development and testing of classification software. As a result, this might facilitate cardiologists' work and lead to faster diagnoses and earlier treatment.

Integrated 68Gallium Labelled Prostate-Specific Membrane Antigen-11 Positron Emission Tomography/Magnetic Resonance Imaging Enhances Discriminatory Power of Multi-Parametric Prostate Magnetic Resonance Imaging.

PubMed

Al-Bayati, Mohammad; Grueneisen, Johannes; Lütje, Susanne; Sawicki, Lino M; Suntharalingam, Saravanabavaan; Tschirdewahn, Stephan; Forsting, Michael; Rübben, Herbert; Herrmann, Ken; Umutlu, Lale; Wetter, Axel

2018-01-01

To evaluate diagnostic accuracy of integrated 68Gallium labelled prostate-specific membrane antigen (68Ga-PSMA)-11 positron emission tomography (PET)/MRI in patients with primary prostate cancer (PCa) as compared to multi-parametric MRI. A total of 22 patients with recently diagnosed primary PCa underwent clinically indicated 68Ga-PSMA-11 PET/CT for initial staging followed by integrated 68Ga-PSMA-11 PET/MRI. Images of multi-parametric magnetic resonance imaging (mpMRI), PET and PET/MRI were evaluated separately by applying Prostate Imaging Reporting and Data System (PIRADSv2) for mpMRI and a 5-point Likert scale for PET and PET/MRI. Results were compared with pathology reports of biopsy or resection. Statistical analyses including receiver operating characteristics analysis were performed to compare the diagnostic performance of mpMRI, PET and PET/MRI. PET and integrated PET/MRI demonstrated a higher diagnostic accuracy than mpMRI (area under the curve: mpMRI: 0.679, PET and PET/MRI: 0.951). The proportion of equivocal results (PIRADS 3 and Likert 3) was considerably higher in mpMRI than in PET and PET/MRI. In a notable proportion of equivocal PIRADS results, PET led to a correct shift towards higher suspicion of malignancy and enabled correct lesion classification. Integrated 68Ga-PSMA-11 PET/MRI demonstrates higher diagnostic accuracy than mpMRI and is particularly valuable in tumours with equivocal results from PIRADS classification. © 2018 S. Karger AG, Basel.

Gadolinium Ethoxybenzyl Diethylenetriamine Pentaacetic Acid (Gd-EOB-DTPA)-Enhanced Magnetic Resonance Imaging and Multidetector-Row Computed Tomography for the Diagnosis of Hepatocellular Carcinoma: A Systematic Review and Meta-analysis.

PubMed

Ye, Feng; Liu, Jun; Ouyang, Han

2015-08-01

The purpose of this meta-analysis was to compare the diagnostic accuracy of gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid (Gd-EOB-DTPA)-enhanced magnetic resonance imaging (MRI) and multidetector-row computed tomography (MDCT) for hepatocellular carcinoma (HCC).Medline, Cochrane, EMBASE, and Google Scholar databases were searched until July 4, 2014, using combinations of the following terms: gadoxetic acid disodium, Gd-EOB-DTPA, multidetector CT, contrast-enhanced computed tomography, and magnetic resonance imaging. Inclusion criteria were as follows: confirmed diagnosis of primary HCC by histopathological examination of a biopsy specimen; comparative study of MRI using Gd-EOB-DTPA and MDCT for diagnosis of HCC; and studies that provided quantitative outcome data. The pooled sensitivity and specificity of the 2 methods were compared, and diagnostic accuracy was assessed with alternative-free response receiver-operating characteristic analysis.Nine studies were included in the meta-analysis, and a total of 1439 lesions were examined. The pooled sensitivity and specificity for 1.5T MRI were 0.95 and 0.96, respectively, for 3.0T MRI were 0.91 and 0.96, respectively, and for MDCT were 0.74 and 0.93, respectively. The pooled diagnostic odds ratio for 1.5T and 3.0T MRI was 242.96, respectively, and that of MDCT was 33.47. To summarize, Gd-EOB-DTPA-enhanced MRI (1.5T and 3.0T) has better diagnostic accuracy for HCC than MDCT.

Additive value of 3T cardiovascular magnetic resonance coronary angiography for detecting coronary artery disease.

PubMed

Zhang, Lijun; Song, Xiantao; Dong, Li; Li, Jianan; Dou, Ruiyu; Fan, Zhanming; An, Jing; Li, Debiao

2018-04-30

The purpose of the work was to evaluate the incremental diagnostic value of free-breathing, contrast-enhanced, whole-heart, 3 T cardiovascular magnetic resonance coronary angiography (CE-MRCA) to stress/rest myocardial perfusion imaging (MPI) and late gadolinium enhancement (LGE) imaging for detecting coronary artery disease (CAD). Fifty-one patients with suspected CAD underwent a comprehensive cardiovascular magnetic resonance (CMR) examination (CE-MRCA, MPI, and LGE). The additive diagnostic value of MRCA to MPI and LGE was evaluated using invasive x-ray coronary angiography (XA) as the standard for defining functionally significant CAD (≥ 50% stenosis in vessels > 2 mm in diameter). 90.2% (46/51) patients (54.0 ± 11.5 years; 71.7% men) completed CE-MRCA successfully. On per-patient basis, compared to MPI/LGE alone or MPI alone, the addition of MRCA resulted in higher sensitivity (100% vs. 76.5%, p < 0.01), no change in specificity (58.3% vs. 66.7%, p = 0.6), and higher accuracy (89.1% vs 73.9%, p < 0.01) for CAD detection (prevalence = 73.9%). Compared to LGE alone, the addition of CE-MRCA resulted in higher sensitivity (97.1% vs. 41.2%, p < 0.01), inferior specificity (83.3% vs. 91.7%, p = 0.02), and higher diagnostic accuracy (93.5% vs. 54.3%, p < 0.01). The inclusion of successful free-breathing, whole-heart, 3 T CE-MRCA significantly improved the sensitivity and diagnostic accuracy as compared to MPI and LGE alone for CAD detection.

Biparametric 3T Magnetic Resonance Imaging for prostatic cancer detection in a biopsy-naïve patient population: a further improvement of PI-RADS v2?

PubMed

Stanzione, Arnaldo; Imbriaco, Massimo; Cocozza, Sirio; Fusco, Ferdinando; Rusconi, Giovanni; Nappi, Carmela; Mirone, Vincenzo; Mangiapia, Francesco; Brunetti, Arturo; Ragozzino, Alfonso; Longo, Nicola

2016-12-01

To prospectively determine the diagnostic accuracy of a biparametric 3T magnetic resonance imaging protocol (BP-MRI) for prostatic cancer detection, compared to a multiparametric MRI protocol (MP-MRI), in a biopsy naïve patient population. Eighty-two untreated patients (mean age 65±7.6years) with clinical suspicion of prostate cancer and/or altered prostate-specific antigen (PSA) levels underwent a MP-MRI, including T2-weighted imaging, diffusion-weighted imaging (with the correspondent apparent diffusion coefficient maps) and dynamic contrast enhanced sequence, followed by prostate biopsy. Two radiologists reviewed both the BP-MRI and the MP-MRI protocols to establish a radiological diagnosis. Receiver operating characteristics curves were obtained to determine the diagnostic performance of the two protocols. The mean PSA level was 8.8±8.1ng/ml. A total of 34 prostatic tumors were identified, with a Gleason score that ranged from 3+3 to 5+4. Of these 34 tumors, 29 were located within the peripheral zone and 5 in the transitional zone. BP-MRI and MP-MRI showed a similar performance in terms of overall diagnostic accuracy, with an area under the curve of 0.91 and 0.93, respectively (p=n.s.). BP-MRI prostate protocol is feasible for prostatic cancer detection compared to a standard MP-MRI protocol, requiring a shorter acquisition and interpretation time, with comparable diagnostic accuracy to the conventional protocol, without the administration of gadolinium-based contrast agent. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Diagnostic accuracy for major depression in multiple sclerosis using self-report questionnaires.

PubMed

Fischer, Anja; Fischer, Marcus; Nicholls, Robert A; Lau, Stephanie; Poettgen, Jana; Patas, Kostas; Heesen, Christoph; Gold, Stefan M

2015-09-01

Multiple sclerosis and major depressive disorder frequently co-occur but depression often remains undiagnosed in this population. Self-rated depression questionnaires are a good option where clinician-based standardized diagnostics are not feasible. However, there is a paucity of data on diagnostic accuracy of self-report measures for depression in multiple sclerosis (MS). Moreover, head-to-head comparisons of common questionnaires are largely lacking. This could be particularly relevant for high-risk patients with depressive symptoms. Here, we compare the diagnostic accuracy of the Beck Depression Inventory (BDI) and 30-item version of the Inventory of Depressive Symptomatology Self-Rated (IDS-SR30) for major depressive disorder (MSS) against diagnosis by a structured clinical interview. Patients reporting depressive symptoms completed the BDI, the IDS-SR30 and underwent diagnostic assessment (Mini International Neuropsychiatric Interview, M.I.N.I.). Receiver-Operating Characteristic analyses were performed, providing error estimates and false-positive/negative rates of suggested thresholds. Data from n = 31 MS patients were available. BDI and IDS-SR30 total score were significantly correlated (r = 0.82). The IDS-SR30total score, cognitive subscore, and BDI showed excellent to good accuracy (area under the curve (AUC) 0.86, 0.91, and 0.85, respectively). Both the IDS-SR30 and the BDI are useful to quantify depressive symptoms showing good sensitivity and specificity. The IDS-SR30 cognitive subscale may be useful as a screening tool and to quantify affective/cognitive depressive symptomatology.

Improving the histopathologic diagnosis of pediatric malignancies in a low-resource setting by combining focused training and telepathology strategies.

PubMed

Santiago, Teresa C; Jenkins, Jesse J; Pedrosa, Francisco; Billups, Catherine; Quintana, Yuri; Ribeiro, Raul C; Qaddoumi, Ibrahim

2012-08-01

Accurate diagnosis is critical for optimal management of pediatric cancer. Pathologists with experience in pediatric oncology are in short supply in the developing world. Telepathology is increasingly used for consultations but its overall contribution to diagnostic accuracy is unknown. We developed a strategy to provide a focused training in pediatric cancer and telepathology support to pathologists in the developing world. After the training period, we compared trainee's diagnoses with those of an experienced pathologist. We next compared the effectiveness of static versus dynamic telepathology review in 127 cases. Results were compared by Fisher's exact test. The diagnoses of the trainee and the expert pathologist differed in only 6.5% of cases (95% CI, 1.2-20.0%). The overall concordance between the telepathology and original diagnoses was 90.6% (115/127; 95% CI, 84.1-94.6%). Brief, focused training in pediatric cancer histopathology can improve diagnostic accuracy. Dynamic and static telepathology analyses are equally effective for diagnostic review. Copyright © 2012 Wiley Periodicals, Inc.

Unenhanced breast MRI (STIR, T2-weighted TSE, DWIBS): An accurate and alternative strategy for detecting and differentiating breast lesions.

PubMed

Telegrafo, Michele; Rella, Leonarda; Stabile Ianora, Amato Antonio; Angelelli, Giuseppe; Moschetta, Marco

2015-10-01

To assess the role of STIR, T2-weighted TSE and DWIBS sequences for detecting and characterizing breast lesions and to compare unenhanced (UE)-MRI results with contrast-enhanced (CE)-MRI and histological findings, having the latter as the reference standard. Two hundred eighty consecutive patients (age range, 27-73 years; mean age±standard deviation (SD), 48.8±9.8years) underwent MR examination with a diagnostic protocol including STIR, T2-weighted TSE, THRIVE and DWIBS sequences. Two radiologists blinded to both dynamic sequences and histological findings evaluated in consensus STIR, T2-weighted TSE and DWIBS sequences and after two weeks CE-MRI images searching for breast lesions. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and diagnostic accuracy for UE-MRI and CE-MRI were calculated. UE-MRI results were also compared with CE- MRI. UE-MRI sequences obtained sensitivity, specificity, diagnostic accuracy, PPV and NPV values of 94%, 79%, 86%, 79% and 94%, respectively. CE-MRI sequences obtained sensitivity, specificity, diagnostic accuracy, PPV and NPV values of 98%, 83%, 90%, 84% and 98%, respectively. No statistically significant difference between UE-MRI and CE-MRI was found. Breast UE-MRI could represent an accurate diagnostic tool and a valid alternative to CE-MRI for evaluating breast lesions. STIR and DWIBS sequences allow to detect breast lesions while T2-weighted TSE sequences and ADC values could be useful for lesion characterization. Copyright © 2015 Elsevier Inc. All rights reserved.

Emotion Perception in Asperger's Syndrome and High-Functioning Autism: The Importance of Diagnostic Criteria and Cue Intensity

ERIC Educational Resources Information Center

Mazefsky, Carla A.; Oswald, Donald P.

2007-01-01

This study compared emotion perception accuracy between children with Asperger's syndrome (AS) and high-functioning autism (HFA). Thirty children were diagnosed with AS or HFA based on empirically supported diagnostic criteria and administered an emotion perception test consisting of facial expressions and tone of voice cues that varied in…

Giant cell arteritis: diagnostic accuracy of MR imaging of superficial cranial arteries in initial diagnosis-results from a multicenter trial.

PubMed

Klink, Thorsten; Geiger, Julia; Both, Marcus; Ness, Thomas; Heinzelmann, Sonja; Reinhard, Matthias; Holl-Ulrich, Konstanze; Duwendag, Dirk; Vaith, Peter; Bley, Thorsten Alexander

2014-12-01

To assess the diagnostic accuracy of contrast material-enhanced magnetic resonance (MR) imaging of superficial cranial arteries in the initial diagnosis of giant cell arteritis ( GCA giant cell arteritis ). Following institutional review board approval and informed consent, 185 patients suspected of having GCA giant cell arteritis were included in a prospective three-university medical center trial. GCA giant cell arteritis was diagnosed or excluded clinically in all patients (reference standard [final clinical diagnosis]). In 53.0% of patients (98 of 185), temporal artery biopsy ( TAB temporal artery biopsy ) was performed (diagnostic standard [ TAB temporal artery biopsy ]). Two observers independently evaluated contrast-enhanced T1-weighted MR images of superficial cranial arteries by using a four-point scale. Diagnostic accuracy, involvement pattern, and systemic corticosteroid ( sCS systemic corticosteroid ) therapy effects were assessed in comparison with the reference standard (total study cohort) and separately in comparison with the diagnostic standard TAB temporal artery biopsy ( TAB temporal artery biopsy subcohort). Statistical analysis included diagnostic accuracy parameters, interobserver agreement, and receiver operating characteristic analysis. Sensitivity of MR imaging was 78.4% and specificity was 90.4% for the total study cohort, and sensitivity was 88.7% and specificity was 75.0% for the TAB temporal artery biopsy subcohort (first observer). Diagnostic accuracy was comparable for both observers, with good interobserver agreement ( TAB temporal artery biopsy subcohort, κ = 0.718; total study cohort, κ = 0.676). MR imaging scores were significantly higher in patients with GCA giant cell arteritis -positive results than in patients with GCA giant cell arteritis -negative results ( TAB temporal artery biopsy subcohort and total study cohort, P < .001). Diagnostic accuracy of MR imaging was high in patients without and with sCS systemic corticosteroid therapy for 5 days or fewer (area under the curve, ≥0.9) and was decreased in patients receiving sCS systemic corticosteroid therapy for 6-14 days. In 56.5% of patients with TAB temporal artery biopsy -positive results (35 of 62), MR imaging displayed symmetrical and simultaneous inflammation of arterial segments. MR imaging of superficial cranial arteries is accurate in the initial diagnosis of GCA giant cell arteritis . Sensitivity probably decreases after more than 5 days of sCS systemic corticosteroid therapy; thus, imaging should not be delayed. Clinical trial registration no. DRKS00000594 . © RSNA, 2014.

Computer-Aided Medical Diagnosis. Literature Review

DTIC Science & Technology

1978-12-15

Croft found a 13% difference in diagnostic accuracy. He considered this difference insignificant in relation to the diagnostic differences caused ...type of diseases diagnosed probably are the major cause of cross-study variability in diagnostic accuracy. The consistency of diagnostic accuracy...REFERENCES ALPEROVITCH, A. and FRAGU, P., A suggestion for an effective use of a computer-aided diagnosis system in screening for hyperthyroidism , Method

Diagnostic accuracy of CTA and MRI/MRA in the evaluation of the cortical venous reflux in the intracranial dural arteriovenous fistula DAVF.

PubMed

Lin, Yen-Heng; Wang, Yu-Fen; Liu, Hon-Man; Lee, Chung-Wei; Chen, Ya-Fang; Hsieh, Hong-Jen

2018-01-01

Computed tomography angiography (CTA) and magnetic resonance imaging/angiography (MRI/MRA) are used for the diagnosis of intracranial dural arteriovenous fistulas (DAVFs). The purpose of this study was to compare the diagnostic accuracy of CTA and magnetic resonance imaging/angiography (MRI/MRA) for detection of cortical venous reflux (CVR) in intracranial DAVFs. The records of patients with angiography-confirmed intracranial DAVFs who also received CTA and MRI/MRA from January 2008 to July 2016 were reviewed. CTA and MRI/MRA were reviewed for signs of CVR, and the diagnostic accuracy of individual signs was evaluated by receiver operating curve (ROC) analysis. A total 108 patients were included in this study. CTA signs of CVR included abnormal dilatation, early enhancement, and the presence of a medullary or pial vein. MRI/MRA signs of CVR included abnormal dilatation, early enhancement, flow-related enhancement, flow void, and medullary or pial venous collaterals. The sensitivity of individual CTA signs ranged from 62 to 96%, and specificities from 79 to 94%. The sensitivities of individual MRI/MRA signs ranged from 58 to 83%, and specificities from 77 to 93%. The area under ROC curve (AUC) of CTA and MRI/MRA were 0.91 and 0.87, respectively (P = 0.04 in direct comparison). In subgroup analysis, CTA had better diagnostic accuracy for higher grade disease (P = 0.05) and non-aggressive manifestation (P = 0.04). Both CTA and MRI/MRA have good diagnostic accuracy for detection of CVR in patients with intracranial DAVFs. There is modest evidence that CTA is better than MRI/MRA.

Accuracy of the radioactive copper incorporation test in the diagnosis of Wilson disease.

PubMed

Członkowska, Anna; Rodo, Maria; Wierzchowska-Ciok, Agata; Smolinski, Lukasz; Litwin, Tomasz

2018-02-08

In Wilson disease (WD), copper accumulates in the liver and other tissues because of mutations in the ATP7B copper transporter gene. Early and effective anticopper treatment is crucial. However, routine diagnostic methods based on clinical findings, copper metabolism tests, liver biopsies and DNA analyses do not always provide a conclusive diagnosis. The aim was to evaluate radioactive copper incorporation as a diagnostic test. We included cases with a diagnosis of WD supported by radiocopper testing and later, when available, confirmed by DNA analysis. Incorporation of 64 Cu was measured at 2, 24 and 48 hours following intravenous injection. Diagnostic accuracy (area under the receiver operating characteristic curve [AUC]), sensitivity, specificity and predictive value were assessed for 24 hours/2 hours and 48 hours/2 hours 64 Cu ratios and compared with serum measurements of ceruloplasmin, copper, non-ceruloplasmin-bound copper and urinary 24-hours copper excretion. Patients having two pathogenic ATP7B mutations (homozygotes/compound heterozygotes) (n = 74) had significantly lower 24 hours/2 hours and 48 hours/2 hours 64 Cu ratios than heterozygote controls (n = 21) (mean 0.14 and 0.12 vs 0.49 and 0.63, respectively; both P < .001). Of note, 24 hours/2 hours and 48 hours/2 hours 64 Cu ratios had excellent diagnostic accuracy, with AUCs approaching 1, and only 24-hours urinary copper excretion displayed similar positive features. Other copper metabolism tests studied had lower accuracy, specificity and sensitivity. The radioactive copper test had excellent diagnostic accuracy and may be useful in the evaluation of new therapies aimed at restoring ATP7B function. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Accuracy of computed tomographic features in differentiating intestinal tuberculosis from Crohn's disease: a systematic review with meta-analysis.

PubMed

Kedia, Saurabh; Sharma, Raju; Sreenivas, Vishnubhatla; Madhusudhan, Kumble Seetharama; Sharma, Vishal; Bopanna, Sawan; Pratap Mouli, Venigalla; Dhingra, Rajan; Yadav, Dawesh Prakash; Makharia, Govind; Ahuja, Vineet

2017-04-01

Abdominal computed tomography (CT) can noninvasively image the entire gastrointestinal tract and assess extraintestinal features that are important in differentiating Crohn's disease (CD) and intestinal tuberculosis (ITB). The present meta-analysis pooled the results of all studies on the role of CT abdomen in differentiating between CD and ITB. We searched PubMed and Embase for all publications in English that analyzed the features differentiating between CD and ITB on abdominal CT. The features included comb sign, necrotic lymph nodes, asymmetric bowel wall thickening, skip lesions, fibrofatty proliferation, mural stratification, ileocaecal area, long segment, and left colonic involvements. Sensitivity, specificity, positive and negative likelihood ratios, and diagnostic odds ratio (DOR) were calculated for all the features. Symmetric receiver operating characteristic curve was plotted for features present in >3 studies. Heterogeneity and publication bias was assessed and sensitivity analysis was performed by excluding studies that compared features on conventional abdominal CT instead of CT enterography (CTE). We included 6 studies (4 CTE, 1 conventional abdominal CT, and 1 CTE+conventional abdominal CT) involving 417 and 195 patients with CD and ITB, respectively. Necrotic lymph nodes had the highest diagnostic accuracy (sensitivity, 23%; specificity, 100%; DOR, 30.2) for ITB diagnosis, and comb sign (sensitivity, 82%; specificity, 81%; DOR, 21.5) followed by skip lesions (sensitivity, 86%; specificity, 74%; DOR, 16.5) had the highest diagnostic accuracy for CD diagnosis. On sensitivity analysis, the diagnostic accuracy of other features excluding asymmetric bowel wall thickening remained similar. Necrotic lymph nodes and comb sign on abdominal CT had the best diagnostic accuracy in differentiating CD and ITB.

Comparison of 3T and 7T susceptibility-weighted angiography of the substantia nigra in diagnosing Parkinson disease.

PubMed

Cosottini, M; Frosini, D; Pesaresi, I; Donatelli, G; Cecchi, P; Costagli, M; Biagi, L; Ceravolo, R; Bonuccelli, U; Tosetti, M

2015-03-01

Standard neuroimaging fails in defining the anatomy of the substantia nigra and has a marginal role in the diagnosis of Parkinson disease. Recently 7T MR target imaging of the substantia nigra has been useful in diagnosing Parkinson disease. We performed a comparative study to evaluate whether susceptibility-weighted angiography can diagnose Parkinson disease with a 3T scanner. Fourteen patients with Parkinson disease and 13 healthy subjects underwent MR imaging examination at 3T and 7T by using susceptibility-weighted angiography. Two expert blinded observers and 1 neuroradiology fellow evaluated the 3T and 7T images of the sample to identify substantia nigra abnormalities indicative of Parkinson disease. Diagnostic accuracy and intra- and interobserver agreement were calculated separately for 3T and 7T acquisitions. Susceptibility-weighted angiography 7T MR imaging can diagnose Parkinson disease with a mean sensitivity of 93%, specificity of 100%, and diagnostic accuracy of 96%. 3T MR imaging diagnosed Parkinson disease with a mean sensitivity of 79%, specificity of 94%, and diagnostic accuracy of 86%. Intraobserver and interobserver agreement was excellent at 7T. At 3T, intraobserver agreement was excellent for experts, and interobserver agreement ranged between good and excellent. The less expert reader obtained a diagnostic accuracy of 89% at 3T. Susceptibility-weighted angiography images obtained at 3T and 7T differentiate controls from patients with Parkinson disease with a higher diagnostic accuracy at 7T. The capability of 3T in diagnosing Parkinson disease might encourage its use in clinical practice. The use of the more accurate 7T should be supported by a dedicated cost-effectiveness study. © 2015 by American Journal of Neuroradiology.

Comparison of Diagnostic Accuracy of Radiation Dose-Equivalent Radiography, Multidetector Computed Tomography and Cone Beam Computed Tomography for Fractures of Adult Cadaveric Wrists

PubMed Central

Neubauer, Jakob; Benndorf, Matthias; Reidelbach, Carolin; Krauß, Tobias; Lampert, Florian; Zajonc, Horst; Kotter, Elmar; Langer, Mathias; Fiebich, Martin; Goerke, Sebastian M.

2016-01-01

Purpose To compare the diagnostic accuracy of radiography, to radiography equivalent dose multidetector computed tomography (RED-MDCT) and to radiography equivalent dose cone beam computed tomography (RED-CBCT) for wrist fractures. Methods As study subjects we obtained 10 cadaveric human hands from body donors. Distal radius, distal ulna and carpal bones (n = 100) were artificially fractured in random order in a controlled experimental setting. We performed radiation dose equivalent radiography (settings as in standard clinical care), RED-MDCT in a 320 row MDCT with single shot mode and RED-CBCT in a device dedicated to musculoskeletal imaging. Three raters independently evaluated the resulting images for fractures and the level of confidence for each finding. Gold standard was evaluated by consensus reading of a high-dose MDCT. Results Pooled sensitivity was higher in RED-MDCT with 0.89 and RED-MDCT with 0.81 compared to radiography with 0.54 (P = < .004). No significant differences were detected concerning the modalities’ specificities (with values between P = .98). Raters' confidence was higher in RED-MDCT and RED-CBCT compared to radiography (P < .001). Conclusion The diagnostic accuracy of RED-MDCT and RED-CBCT for wrist fractures proved to be similar and in some parts even higher compared to radiography. Readers are more confident in their reporting with the cross sectional modalities. Dose equivalent cross sectional computed tomography of the wrist could replace plain radiography for fracture diagnosis in the long run. PMID:27788215

Artificial neural network retrained to detect myocardial ischemia using a Japanese multicenter database.

PubMed

Nakajima, Kenichi; Okuda, Koichi; Watanabe, Satoru; Matsuo, Shinro; Kinuya, Seigo; Toth, Karin; Edenbrandt, Lars

2018-03-07

An artificial neural network (ANN) has been applied to detect myocardial perfusion defects and ischemia. The present study compares the diagnostic accuracy of a more recent ANN version (1.1) with the initial version 1.0. We examined 106 patients (age, 77 ± 10 years) with coronary angiographic findings, comprising multi-vessel disease (≥ 50% stenosis) (52%) or old myocardial infarction (27%), or who had undergone coronary revascularization (30%). The ANN versions 1.0 and 1.1 were trained in Sweden (n = 1051) and Japan (n = 1001), respectively, using 99m Tc-methoxyisobutylisonitrile myocardial perfusion images. The ANN probabilities (from 0.0 to 1.0) of stress defects and ischemia were calculated in candidate regions of abnormalities. The diagnostic accuracy was compared using receiver-operating characteristics (ROC) analysis and the calculated area under the ROC curve (AUC) using expert interpretation as the gold standard. Although the AUC for stress defects was 0.95 and 0.93 (p = 0.27) for versions 1.1 and 1.0, respectively, that for detecting ischemia was significantly improved in version 1.1 (p = 0.0055): AUC 0.96 for version 1.1 (sensitivity 87%, specificity 96%) vs. 0.89 for version 1.0 (sensitivity 78%, specificity 97%). The improvement in the AUC shown by version 1.1 was also significant for patients with neither coronary revascularization nor old myocardial infarction (p = 0.0093): AUC = 0.98 for version 1.1 (sensitivity 88%, specificity 100%) and 0.88 for version 1.0 (sensitivity 76%, specificity 100%). Intermediate ANN probability between 0.1 and 0.7 was more often calculated by version 1.1 compared with version 1.0, which contributed to the improved diagnostic accuracy. The diagnostic accuracy of the new version was also improved in patients with either single-vessel disease or no stenosis (n = 47; AUC, 0.81 vs. 0.66 vs. p = 0.0060) when coronary stenosis was used as a gold standard. The diagnostic ability of the ANN version 1.1 was improved by retraining using the Japanese database, particularly for identifying ischemia.

Assessment of Breast Specimens With or Without Calcifications in Diagnosing Malignant and Atypia for Mammographic Breast Microcalcifications Without Mass: A STARD-Compliant Diagnostic Accuracy Article.

PubMed

Cheung, Yun-Chung; Juan, Yu-Hsiang; Ueng, Shir-Hwa; Lo, Yung-Feng; Huang, Pei-Chin; Lin, Yu-Ching; Chen, Shin-Cheh

2015-10-01

Presence of microcalcifications within the specimens frequently signifies a successful attempt of stereotactic vacuum-assisted breast biopsy (VABB) in obtaining a pathologic diagnosis of the breast microcalcifications. In this study, the authors aimed to assess and compare the accuracy and consistency of calcified or noncalcified specimens obtained from same sites of sampling on isolated microcalcifications without mass in diagnosing high-risk and malignant lesions. To the best of our knowledge, an individual case-based prospective comparison has not been reported.With the approval from institutional review board of our hospital (Chang Gung Memorial Hospital), the authors retrospectively reviewed all clinical cases of stereotactic VABBs on isolated breast microcalcifications without mass from our database. The authors included those having either surgery performed or had clinical follow-up of at least 3 years for analysis. All the obtained specimens with or without calcification were identified using specimen radiographs and separately submitted for pathologic evaluation. The concordance of diagnosis was assessed for both atypia and malignant lesions.A total of 390 stereotactic VABB procedures (1206 calcified and 1456 noncalcified specimens) were collected and reviewed. The consistent rates between calcified and noncalcified specimens were low for atypia and malignant microcalcifications (44.44% in flat epithelial atypia, 46.51% in atypical ductal hyperplasia, 55.73% in ductal carcinoma in situ, and 71.42% in invasive ductal carcinoma). The discordance in VABB diagnoses indicated that 41.33% of malignant lesions would be misdiagnosed by noncalcified specimens. Furthermore, calcified specimens showed higher diagnostic accuracy of breast cancer as compared with the noncalcified specimens (91.54 % versus 69.49%, respectively). The evaluation of both noncalcified specimens and calcified specimens did not show improvement of diagnostic accuracy as compared with evaluating calcified specimens alone (91.54% versus 91.54%, respectively).The high prevalence of diagnostic discordance between the calcified and noncalcified specimens indicated the higher value of calcified specimens in diagnosing atypia and malignant microcalcifications. Noncalcified specimens did not provide additional diagnostic benefit from this study. The separation of calcified and noncalcified specimens may facilitate more focused interpretation from pathologists among the large number of specimens.

Systematic Review and Meta-Analysis of Studies Evaluating Diagnostic Test Accuracy: A Practical Review for Clinical Researchers-Part II. Statistical Methods of Meta-Analysis

PubMed Central

Lee, Juneyoung; Kim, Kyung Won; Choi, Sang Hyun; Huh, Jimi

2015-01-01

Meta-analysis of diagnostic test accuracy studies differs from the usual meta-analysis of therapeutic/interventional studies in that, it is required to simultaneously analyze a pair of two outcome measures such as sensitivity and specificity, instead of a single outcome. Since sensitivity and specificity are generally inversely correlated and could be affected by a threshold effect, more sophisticated statistical methods are required for the meta-analysis of diagnostic test accuracy. Hierarchical models including the bivariate model and the hierarchical summary receiver operating characteristic model are increasingly being accepted as standard methods for meta-analysis of diagnostic test accuracy studies. We provide a conceptual review of statistical methods currently used and recommended for meta-analysis of diagnostic test accuracy studies. This article could serve as a methodological reference for those who perform systematic review and meta-analysis of diagnostic test accuracy studies. PMID:26576107

Diffusion Tensor Imaging in Chronic Inflammatory Demyelinating Polyneuropathy: Diagnostic Accuracy and Correlation With Electrophysiology.

PubMed

Kronlage, Moritz; Pitarokoili, Kalliopi; Schwarz, Daniel; Godel, Tim; Heiland, Sabine; Yoon, Min-Suk; Bendszus, Martin; Bäumer, Philipp

2017-11-01

The aims of this study were to assess diagnostic accuracy of diffusion tensor imaging (DTI) in chronic inflammatory demyelinating polyneuropathy (CIDP), to correlate DTI with electrophysiological parameters, and to evaluate whether radial diffusivity (RD) and axial diffusivity (AD) might serve as specific biomarkers of demyelinating and axonal pathology. This prospective study was approved by the institutional ethics committee, and written informed consent was obtained from all participants. Magnetic resonance neurography of upper and lower extremity nerves (median, ulnar, radial, sciatic, tibial) was performed by single-shot DTI sequences at 3.0 T in 18 patients with a diagnosis of CIDP and 18 healthy controls, matched to age and sex. The scalar readout parameters nerve fractional anisotropy (FA), mean diffusivity (MD), RD, and AD were obtained after manual segmentation and postprocessing and compared between patients and controls. Diagnostic accuracy was assessed by receiver operating characteristic analysis, and cutoff values were calculated by maximizing the Youden index. All patients underwent a complementary electroneurography and correlation of electrophysiological markers and DTI parameters was analyzed and described by Pearson and Spearman coefficients. Nerve FA was decreased to a mean of 0.42 ± 0.08 in patients compared with 0.52 ± 0.04 in healthy controls (P < 0.001). This decrease in FA was a result of an increase of RD (P = 0.02), whereas AD did not differ between the two groups. Of all DTI parameters, FA showed best diagnostic accuracy with a receiver operating characteristic area under the curve of 0.90. Optimal cutoff for an average FA of all analyzed nerves was 0.47, yielding a sensitivity of 0.83 and a specificity of 0.94. Fractional anisotropy and RD correlated strongly with electrophysiological markers of demyelination, whereas AD did not correlate with markers of axonal neuropathy. Diffusion tensor imaging yields valid quantitative biomarkers in CIDP and might aid in diagnosis with high diagnostic accuracy. Fractional anisotropy and RD may serve as parameters of myelin sheath integrity, but AD is unable to reflect axonal damage in CIDP.

Accuracy of LightCycler® SeptiFast for the detection and identification of pathogens in the blood of patients with suspected sepsis: a systematic review protocol

PubMed Central

Wilson, Claire; Blackwood, Bronagh; McAuley, Danny F; Perkins, Gavin D; McMullan, Ronan; Gates, Simon; Warhurst, Geoffrey

2012-01-01

Background There is growing interest in the potential utility of molecular diagnostics in improving the detection of life-threatening infection (sepsis). LightCycler® SeptiFast is a multipathogen probe-based real-time PCR system targeting DNA sequences of bacteria and fungi present in blood samples within a few hours. We report here the protocol of the first systematic review of published clinical diagnostic accuracy studies of this technology when compared with blood culture in the setting of suspected sepsis. Methods/design Data sources: the Cochrane Database of Systematic Reviews, the Database of Abstracts of Reviews of Effects (DARE), the Health Technology Assessment Database (HTA), the NHS Economic Evaluation Database (NHSEED), The Cochrane Library, MEDLINE, EMBASE, ISI Web of Science, BIOSIS Previews, MEDION and the Aggressive Research Intelligence Facility Database (ARIF). Study selection: diagnostic accuracy studies that compare the real-time PCR technology with standard culture results performed on a patient's blood sample during the management of sepsis. Data extraction: three reviewers, working independently, will determine the level of evidence, methodological quality and a standard data set relating to demographics and diagnostic accuracy metrics for each study. Statistical analysis/data synthesis: heterogeneity of studies will be investigated using a coupled forest plot of sensitivity and specificity and a scatter plot in Receiver Operator Characteristic (ROC) space. Bivariate model method will be used to estimate summary sensitivity and specificity. The authors will investigate reporting biases using funnel plots based on effective sample size and regression tests of asymmetry. Subgroup analyses are planned for adults, children and infection setting (hospital vs community) if sufficient data are uncovered. Dissemination Recommendations will be made to the Department of Health (as part of an open-access HTA report) as to whether the real-time PCR technology has sufficient clinical diagnostic accuracy potential to move forward to efficacy testing during the provision of routine clinical care. Registration PROSPERO—NIHR Prospective Register of Systematic Reviews (CRD42011001289). PMID:22240646

Tourniquet Test for Dengue Diagnosis: Systematic Review and Meta-analysis of Diagnostic Test Accuracy.

PubMed

Grande, Antonio Jose; Reid, Hamish; Thomas, Emma; Foster, Charlie; Darton, Thomas C

2016-08-01

Dengue fever is a ubiquitous arboviral infection in tropical and sub-tropical regions, whose incidence has increased over recent decades. In the absence of a rapid point of care test, the clinical diagnosis of dengue is complex. The World Health Organisation has outlined diagnostic criteria for making the diagnosis of dengue infection, which includes the use of the tourniquet test (TT). To assess the quality of the evidence supporting the use of the TT and perform a diagnostic accuracy meta-analysis comparing the TT to antibody response measured by ELISA. A comprehensive literature search was conducted in the following databases to April, 2016: MEDLINE (PubMed), EMBASE, Cochrane Central Register of Controlled Trials, BIOSIS, Web of Science, SCOPUS. Studies comparing the diagnostic accuracy of the tourniquet test with ELISA for the diagnosis of dengue were included. Two independent authors extracted data using a standardized form. A total of 16 studies with 28,739 participants were included in the meta-analysis. Pooled sensitivity for dengue diagnosis by TT was 58% (95% Confidence Interval (CI), 43%-71%) and the specificity was 71% (95% CI, 60%-80%). In the subgroup analysis sensitivity for non-severe dengue diagnosis was 55% (95% CI, 52%-59%) and the specificity was 63% (95% CI, 60%-66%), whilst sensitivity for dengue hemorrhagic fever diagnosis was 62% (95% CI, 53%-71%) and the specificity was 60% (95% CI, 48%-70%). Receiver-operator characteristics demonstrated a test accuracy (AUC) of 0.70 (95% CI, 0.66-0.74). The tourniquet test is widely used in resource poor settings despite currently available evidence demonstrating only a marginal benefit in making a diagnosis of dengue infection alone. The protocol for this systematic review was registered at CRD42015020323.

Quality of data regarding diagnoses of spinal disorders in administrative databases. A multicenter study.

PubMed

Faciszewski, T; Broste, S K; Fardon, D

1997-10-01

The purpose of the present study was to evaluate the accuracy of data regarding diagnoses of spinal disorders in administrative databases at eight different institutions. The records of 189 patients who had been managed for a disorder of the lumbar spine were independently reviewed by a physician who assigned the appropriate diagnostic codes according to the International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM). The age range of the 189 patients was seventeen to eighty-four years. The six major diagnostic categories studied were herniation of a lumbar disc, a previous operation on the lumbar spine, spinal stenosis, cauda equina syndrome, acquired spondylolisthesis, and congenital spondylolisthesis. The diagnostic codes assigned by the physician were compared with the codes that had been assigned during the ordinary course of events by personnel in the medical records department of each of the eight hospitals. The accuracy of coding was also compared among the eight hospitals, and it was found to vary depending on the diagnosis. Although there were both false-negative and false-positive codes at each institution, most errors were related to the low sensitivity of coding for previous spinal operations: only seventeen (28 per cent) of sixty-one such diagnoses were coded correctly. Other errors in coding were less frequent, but their implications for conclusions drawn from the information in administrative databases depend on the frequency of a diagnosis and its importance in an analysis. This study demonstrated that the accuracy of a diagnosis of a spinal disorder recorded in an administrative database varies according to the specific condition being evaluated. It is necessary to document the relative accuracy of specific ICD-9-CM diagnostic codes in order to improve the ability to validate the conclusions derived from investigations based on administrative databases.

High diagnostic accuracy of subcutaneous Triptorelin test compared with GnRH test for diagnosing central precocious puberty in girls.

PubMed

Freire, Analía Verónica; Escobar, María Eugenia; Gryngarten, Mirta Graciela; Arcari, Andrea Josefina; Ballerini, María Gabriela; Bergadá, Ignacio; Ropelato, María Gabriela

2013-03-01

The GnRH test is the gold standard to confirm the diagnosis of central precocious puberty (CPP); however, this compound is not always readily available. Diagnostic accuracy of subcutaneous GnRH analogues tests compared to classical GnRH test has not been reported. To evaluate the diagnostic accuracy of Triptorelin test (index test) compared to the GnRH test (reference test) in girls with suspicion of CPP. A prospective, case-control, randomized clinical trial was performed. CPP or precocious thelarche (PT) was diagnosed according to maximal LH response to GnRH test and clinical characteristics during follow-up. Forty-six girls with premature breast development randomly underwent two tests: (i) intravenous GnRH 100 μg, (ii) subcutaneous Triptorelin acetate (0.1 mg/m(2), to a maximum of 0.1 mg) with blood sampling at 0, 3 and 24 h for LH, FSH and estradiol ascertainment. Gonadotrophins and estradiol responses to Triptorelin test were measured by ultrasensitive assays. Clinical features were similar between CPP (n = 33) and PT (n = 13) groups. Using receiver operating characteristic curves, maximal LH response (LH-3 h) under Triptorelin test ≥ 7 IU/l by immunofluorometric assay (IFMA) or ≥ 8 IU/l by electrochemiluminescence immunoassay (ECLIA) confirmed the diagnosis of CPP with specificity of 1.00 (95% CI: 0.75-1.00) and sensitivity 0.76 (95% CI: 0.58-0.89). Considering either LH-3 h or maximal estradiol response at 24 h (cut-off value, 295 pm), maintaining the specificity at 1.00, the test sensitivity increased to 0.94 (95% CI: 0.80-0.99) and the diagnostic efficiency to 96%. The Triptorelin test had high accuracy for the differential diagnosis of CPP vs PT in girls providing a valid alternative to the classical GnRH test. This test also allowed a comprehensive evaluation of the pituitary-ovarian axis. © 2012 Blackwell Publishing Ltd.

Diagnostic efficiency of demographically corrected Wechsler Adult Intelligence Scale-III and Wechsler Memory Scale-III indices in moderate to severe traumatic brain injury and lower education levels.

PubMed

Walker, Alexandra J; Batchelor, Jennifer; Shores, E Arthur; Jones, Mike

2009-11-01

Despite the sensitivity of neuropsychological tests to educational level, improved diagnostic accuracy for demographically corrected scores has yet to be established. Diagnostic efficiency statistics of Wechsler Adult Intelligence Scale-III (WAIS-III) and Wechsler Memory Scale-III (WMS-III) indices that were corrected for education, sex, and age (demographically corrected) were compared with age corrected indices in individuals aged 16 to 75 years with moderate to severe traumatic brain injury (TBI) and 12 years or less education. TBI participants (n = 100) were consecutive referrals to an outpatient rehabilitation service and met careful selection criteria. Controls (n = 100) were obtained from the WAIS-III/WMS-III standardization sample. Demographically corrected indices did not provide higher diagnostic efficiency than age corrected indices and this result was supported by reanalysis of the TBI group against a larger and unmatched control group. Processing Speed Index provided comparable diagnostic accuracy to that of combined indices. Demographically corrected indices were associated with higher cut-scores to maximize overall classification, reflecting the upward adjustment of those scores in a lower education sample. This suggests that, in clinical practice, the test results of individuals with limited education may be more accurately interpreted with the application of demographic corrections. Diagnostic efficiency statistics are presented, and future research directions are discussed.

Magnetic Resonance Angiography in the Diagnosis of Cerebral Arteriovenous Malformation and Dural Arteriovenous Fistulas: Comparison of Time-Resolved Magnetic Resonance Angiography and Three Dimensional Time-of-Flight Magnetic Resonance Angiography

PubMed Central

Cheng, Yu-Ching; Chen, Hung-Chieh; Wu, Chen-Hao; Wu, Yi-Ying; Sun, Ming-His; Chen, Wen-Hsien; Chai, Jyh-Wen; Chi-Chang Chen, Clayton

2016-01-01

Background Traditional digital subtraction angiography (DSA) is currently the gold standard diagnostic method for the diagnosis and evaluation of cerebral arteriovenous malformation (AVM) and dural arteriovenous fistulas (dAVF). Objectives The aim of this study was to analyze different less invasive magnetic resonance angiography (MRA) images, time-resolved MRA (TR-MRA) and three-dimensional time-of-flight MRA (3D TOF MRA) to identify their diagnostic accuracy and to determine which approach is most similar to DSA. Patients and Methods A total of 41 patients with AVM and dAVF at their initial evaluation or follow-up after treatment were recruited in this study. We applied time-resolved angiography using keyhole (4D-TRAK) MRA to perform TR-MRA and 3D TOF MRA examinations simultaneously followed by DSA, which was considered as a standard reference. Two experienced neuroradiologists reviewed the images to compare the diagnostic accuracy, arterial feeder and venous drainage between these two MRA images. Inter-observer agreement for different MRA images was assessed by Kappa coefficient and the differences of diagnostic accuracy between MRA images were evaluated by the Wilcoxon rank sum test. Results Almost all vascular lesions (92.68%) were correctly diagnosed using 4D-TRAK MRA. However, 3D TOF MRA only diagnosed 26 patients (63.41%) accurately. There were statistically significant differences regarding lesion diagnostic accuracy (P = 0.008) and venous drainage identification (P < 0.0001) between 4D-TRAK MRA and 3D TOF MRA. The results indicate that 4D-TRAK MRA is superior to 3D TOF MRA in the assessment of lesions. Conclusion Compared with 3D TOF MRA, 4D-TRAK MRA proved to be a more reliable screening modality and follow-up method for the diagnosis of cerebral AVM and dAVF. PMID:27679690

Progressing Toward a Cohesive Pediatric 18F-FDG PET/MR Protocol: Is Administration of Gadolinium Chelates Necessary?

PubMed

Klenk, Christopher; Gawande, Rakhee; Tran, Vy Thao; Leung, Jennifer Trinh; Chi, Kevin; Owen, Daniel; Luna-Fineman, Sandra; Sakamoto, Kathleen M; McMillan, Alex; Quon, Andy; Daldrup-Link, Heike E

2016-01-01

With the increasing availability of integrated PET/MR scanners, the utility and need for MR contrast agents for combined scans is questioned. The purpose of our study was to evaluate whether administration of gadolinium chelates is necessary for evaluation of pediatric tumors on (18)F-FDG PET/MR images. First, in 119 pediatric patients with primary and secondary tumors, we used 14 diagnostic criteria to compare the accuracy of several MR sequences: unenhanced T2-weighted fast spin-echo imaging; unenhanced diffusion-weighted imaging; and-before and after gadolinium chelate contrast enhancement-T1-weighted 3-dimensional spoiled gradient echo LAVA (liver acquisition with volume acquisition) imaging. Next, in a subset of 36 patients who had undergone (18)F-FDG PET within 3 wk of MRI, we fused the PET images with the unenhanced T2-weighted MR images (unenhanced (18)F-FDG PET/MRI) and the enhanced T1-weighted MR images (enhanced (18)F-FDG PET/MRI). Using the McNemar test, we compared the accuracy of the two types of fused images using the 14 diagnostic criteria. We also evaluated the concordance between (18)F-FDG avidity and gadolinium chelate enhancement. The standard of reference was histopathologic results, surgical notes, and follow-up imaging. There was no significant difference in diagnostic accuracy between the unenhanced and enhanced MR images. Accordingly, there was no significant difference in diagnostic accuracy between the unenhanced and enhanced (18)F-FDG PET/MR images. (18)F-FDG avidity and gadolinium chelate enhancement were concordant in 30 of the 36 patients and 106 of their 123 tumors. Gadolinium chelate administration is not necessary for accurate diagnostic characterization of most solid pediatric malignancies on (18)F-FDG PET/MR images, with the possible exception of focal liver lesions. © 2016 by the Society of Nuclear Medicine and Molecular Imaging, Inc.

The STARD statement for reporting diagnostic accuracy studies: application to the history and physical examination.

PubMed

Simel, David L; Rennie, Drummond; Bossuyt, Patrick M M

2008-06-01

The Standards for Reporting of Diagnostic Accuracy (STARD) statement provided guidelines for investigators conducting diagnostic accuracy studies. We reviewed each item in the statement for its applicability to clinical examination diagnostic accuracy research, viewing each discrete aspect of the history and physical examination as a diagnostic test. Nonsystematic review of the STARD statement. Two former STARD Group participants and 1 editor of a journal series on clinical examination research reviewed each STARD item. Suggested interpretations and comments were shared to develop consensus. The STARD Statement applies generally well to clinical examination diagnostic accuracy studies. Three items are the most important for clinical examination diagnostic accuracy studies, and investigators should pay particular attention to their requirements: describe carefully the patient recruitment process, describe participant sampling and address if patients were from a consecutive series, and describe whether the clinicians were masked to the reference standard tests and whether the interpretation of the reference standard test was masked to the clinical examination components or overall clinical impression. The consideration of these and the other STARD items in clinical examination diagnostic research studies would improve the quality of investigations and strengthen conclusions reached by practicing clinicians. The STARD statement provides a very useful framework for diagnostic accuracy studies. The group correctly anticipated that there would be nuances applicable to studies of the clinical examination. We offer guidance that should enhance their usefulness to investigators embarking on original studies of a patient's history and physical examination.

Usefulness of composite methionine-positron emission tomography/3.0-tesla magnetic resonance imaging to detect the localization and extent of early-stage Cushing adenoma.

PubMed

Ikeda, Hidetoshi; Abe, Takehiko; Watanabe, Kazuo

2010-04-01

Fifty to eighty percent of Cushing disease is diagnosed by typical endocrine responses. Recently, the number of diagnoses of Cushing disease without typical Cushing syndrome has been increasing; therefore, improving ways to determine the localization of the adenoma and making an early diagnosis is important. This study was undertaken to determine the present diagnostic accuracy for Cushing microadenoma and to compare the differences in diagnostic accuracy between MR imaging and PET/MR imaging. During the past 3 years the authors analyzed the diagnostic accuracy in a series of 35 patients with Cushing adenoma that was verified by surgical pituitary exploration. All 35 cases of Cushing disease, including 20 cases of "overt" and 15 cases of "preclinical" Cushing disease, were studied. Superconductive MR images (1.5 or 3.0 T) and composite images from FDG-PET or methionine (MET)-PET and 3.0-T MR imaging were compared with the localization of adenomas verified by surgery. The diagnostic accuracy of superconductive MR imaging for detecting the localization of Cushing microadenoma was only 40%. The causes of unsatisfactory results for superconductive MR imaging were false-negative results (10 cases), false-positive results (6 cases), and instances of double pituitary adenomas (3 cases). In contrast, the accuracy of microadenoma localization using MET-PET/3.0-T MR imaging was 100% and that of FDG-PET/3.0-T MR imaging was 73%. Moreover, the adenoma location was better delineated on MET-PET/MR images than on FDG-PET/MR images. There was no significant difference in maximum standard uptake value of adenomas evaluated by MET-PET between preclinical Cushing disease and overt Cushing disease. Composite MET-PET/3.0-T MR imaging is useful for the improvement of the delineation of Cushing microadenoma and offers high-quality detectability for early-stage Cushing adenoma.

Comparison of fine-needle aspiration and core needle biopsy under ultrasonographic guidance for detecting malignancy and for the tissue-specific diagnosis of salivary gland tumors.

PubMed

Eom, H-J; Lee, J H; Ko, M-S; Choi, Y J; Yoon, R G; Cho, K J; Nam, S Y; Baek, J H

2015-06-01

Diagnostic test accuracy studies for ultrasonography-guided fine-needle aspiration and ultrasonography-guided core needle biopsy have shown inconclusive results due to their heterogenous study designs. Our aim was to compare the diagnostic accuracy of ultrasonography-guided fine-needle aspiration versus ultrasonography-guided core needle biopsy for detecting malignant tumors of the salivary gland and for the tissue-specific diagnosis of salivary gland tumors in a single tertiary hospital. This retrospective study was approved by our institutional review board and informed consent was waived. Four hundred twelve patients who underwent ultrasonography-guided fine-needle aspiration (n = 155) or ultrasonography-guided core needle biopsy (n = 257) with subsequent surgical confirmation or clinical follow-up were enrolled. We compared the diagnostic accuracy of ultrasonography-guided fine-needle aspiration and ultrasonography-guided core needle biopsy regarding malignant salivary gland tumors and the correct tissue-specific diagnosis of benign and malignant tumors. We also tested the difference between these procedures according to the operator's experience and lesion characteristics. The inconclusive rates of ultrasonography-guided fine-needle aspiration and ultrasonography-guided core needle biopsy were 19% and 4%, respectively (P < .001). The overall accuracy of ultrasonography-guided core needle biopsy for diagnosing malignant tumors was significantly higher than that of ultrasonography-guided fine-needle aspiration (P = .024). The correct tissue-specific diagnosis rates of ultrasonography-guided fine-needle aspiration and ultrasonography-guided core needle biopsy were 95% versus 97% for benign tumors (P = .648) and 67% versus 80% for malignant tumors (P = .310). Trainees showed significantly lower accuracy with ultrasonography-guided fine-needle aspiration than with ultrasonography-guided core needle biopsy for diagnosing malignant tumors (P = .021). There was no difference between the diagnostic accuracy of ultrasonography-guided fine-needle aspiration and ultrasonography-guided core needle biopsy according to the internal composition of the lesions. There were no complications requiring intervention or hospitalization in our patients. Ultrasonography-guided core needle biopsy is superior to ultrasonography-guided fine-needle aspiration in detecting and characterizing malignant tumors of the salivary gland and could emerge as the diagnostic method of choice for patients presenting with a salivary gland mass. © 2015 by American Journal of Neuroradiology.

The role of computerized diagnostic proposals in the interpretation of the 12-lead electrocardiogram by cardiology and non-cardiology fellows.

PubMed

Novotny, Tomas; Bond, Raymond; Andrsova, Irena; Koc, Lumir; Sisakova, Martina; Finlay, Dewar; Guldenring, Daniel; Spinar, Jindrich; Malik, Marek

2017-05-01

Most contemporary 12-lead electrocardiogram (ECG) devices offer computerized diagnostic proposals. The reliability of these automated diagnoses is limited. It has been suggested that incorrect computer advice can influence physician decision-making. This study analyzed the role of diagnostic proposals in the decision process by a group of fellows of cardiology and other internal medicine subspecialties. A set of 100 clinical 12-lead ECG tracings was selected covering both normal cases and common abnormalities. A team of 15 junior Cardiology Fellows and 15 Non-Cardiology Fellows interpreted the ECGs in 3 phases: without any diagnostic proposal, with a single diagnostic proposal (half of them intentionally incorrect), and with four diagnostic proposals (only one of them being correct) for each ECG. Self-rated confidence of each interpretation was collected. Availability of diagnostic proposals significantly increased the diagnostic accuracy (p<0.001). Nevertheless, in case of a single proposal (either correct or incorrect) the increase of accuracy was present in interpretations with correct diagnostic proposals, while the accuracy was substantially reduced with incorrect proposals. Confidence levels poorly correlated with interpretation scores (rho≈2, p<0.001). Logistic regression showed that an interpreter is most likely to be correct when the ECG offers a correct diagnostic proposal (OR=10.87) or multiple proposals (OR=4.43). Diagnostic proposals affect the diagnostic accuracy of ECG interpretations. The accuracy is significantly influenced especially when a single diagnostic proposal (either correct or incorrect) is provided. The study suggests that the presentation of multiple computerized diagnoses is likely to improve the diagnostic accuracy of interpreters. Copyright © 2017 Elsevier B.V. All rights reserved.

[Contrast agent improves diagnostic value of dobutamine stress echocardiography].

PubMed

Uehara, H; Yamamoto, T; Hirano, Y; Ozasa, Y; Yamada, S; Ikawa, H; Ishikawa, K

2001-03-01

Suboptimal endocardial definition reduces the diagnostic value of stress echocardiography for coronary artery disease, but intravenous infusion of a left ventricular contrast agent (Albunex) may enhance endocardial border delineation and improve the diagnostic value of dobutamine stress echocardiography. Fifty-six patients, 38 with myocardial infarction, 16 with angina pectoris and two normal subjects, were enrolled in this study. Dobutamine was infused in scalar doses of 5 to 40 micrograms/kg/min. Intravenous infusion of Albunex (0.15 ml/kg) was administered at rest and during peak dobutamine stress during monitoring of the apical four-chamber view. The left ventricle in the apical four-chamber view was divided into six segments and an endocardial delineation score of 0 to 3 (none to excellent visualization) was given to each segment. Endocardial delineation score was increased after Albunex infusion from 2.0 to 2.3 in the basal-septal, 2.0 to 2.4 in the mid-septal, 1.1 to 1.8 in the apical-septal, 0.7 to 1.2 in the apical-lateral, 0.9 to 1.6 in the mid-lateral, and 1.2 to 1.9 in the basal-lateral segments during peak dobutamine administration. Endocardial border resolution in the lateral wall showed greater improvement than in the septal wall after Albunex infusion. Diagnostic values in the left anterior descending artery territory failed to improve with Albunex infusion (sensitivity 82% to 89%, specificity 94% to 89%, and accuracy 86% to 89%), whereas a higher diagnostic accuracy was noted in the left circumflex artery territory with Albunex compared to without Albunex (sensitivity 63% to 81%, specificity 88% to 98%, and accuracy 80% to 93%, p < 0.05). Contrast agent improves the diagnostic accuracy of dobutamine stress echocardiography in the left circumflex artery territory.

Seeking a valid gold standard for an innovative, dialect-neutral language test.

PubMed

Pearson, Barbara Zurer; Jackson, Janice E; Wu, Haotian

2014-04-01

PURPOSE In this study, the authors explored alternative gold standards to validate an innovative, dialect-neutral language assessment. METHOD Participants were 78 African American children, ages 5;0 (years;months) to 6;11. Twenty participants had previously been identified as having language impairment. The Diagnostic Evaluation of Language Variation-Norm Referenced (DELV-NR; Seymour, Roeper, & J. de Villiers, 2005) was administered, and concurrent language samples (LSs) were collected. Using LS profiles as the gold standard, sensitivity, specificity, and other measures of diagnostic accuracy were compared for diagnoses made from the DELV-NR and participants' clinical status prior to recruitment. In a second analysis, the authors used results from the first analysis to make evidence-based adjustments in the estimates of DELV-NR diagnostic accuracy. RESULTS Accuracy of the DELV-NR relative to LS profiles was greater than that of prior diagnoses, indicating that the DELV-NR was an improvement over preexisting diagnoses for this group. Specificity met conventional standards, but sensitivity was somewhat low. Reanalysis using the positive and negative predictive power of the preexisting diagnosis in a discrepant-resolution procedure revealed that estimates for sensitivity and specificity for the DELV-NR were .85 and .93, respectively. CONCLUSION The authors found that, even after making allowances for the imperfection of available gold standards, clinical decisions made with the DELV-NR achieved high values on conventional measures of diagnostic accuracy.

The diagnostic accuracy of dermoscopy for scabies.

PubMed

Park, Ju Hyuk; Kim, Chul Woo; Kim, Sang Seok

2012-05-01

Scabies is a contagious skin infestation characterized clinically by nocturnal pruritus, visible burrows and contagiousness. Dermoscopy has been suggested as an alternative for diagnosing scabies. But, there have been few well-designed studies evaluating the diagnostic accuracy of dermoscopy. We tried to confirm the diagnostic accuracy of dermoscopy for diagnosing scabies. We also tried to demonstrate specific circumstances in which dermoscopic identification of mites ("with dermoscopy") is more useful in diagnosing scabies, and to identify the specific clinical findings that could be used as a possible marker in diagnosing scabies. We compared the scraping procedure "with dermoscopy" and "without it" in 49 patients, measuring the duration and outcome of each procedure. Also, we tried to find the specific clinical factors associated with our objects. The skin scraping "with dermoscopy" was superior to "without it" with respect to the duration and accuracy of the procedure. A history of previous steroid treatment was associated with the superiority of dermoscopy. The correlation between the presence of visible burrows and the positive outcomes of "with dermoscopy" was statistically significant. Skin scraping with dermoscopy is implicated as the diagnostic method of choice for scabies at the present time. Dermoscopy is especially useful in diagnosis of incognito scabies. In addition, the presence of visible burrows could be a reliable positive marker of scabies in the absence of dermoscopy or microscopy data.

Diagnostic accuracy of presepsin (sCD14-ST) as a biomarker of infection and sepsis in the emergency department.

PubMed

de Guadiana Romualdo, Luis García; Torrella, Patricia Esteban; Acebes, Sergio Rebollo; Otón, María Dolores Albaladejo; Sánchez, Roberto Jiménez; Holgado, Ana Hernando; Santos, Enrique Jiménez; Freire, Alejandro Ortín

2017-01-01

Presepsin is a promising biomarker for the diagnosis and prognosis of sepsis. However, results reported about its value to diagnose sepsis in an emergency department (ED) are controversial, probably due to differences in the design of the studies. We have evaluated the diagnostic accuracy of presepsin for infection and sepsis, compared with procalcitonin (PCT) and C-reactive protein (CRP), in patients presenting to the emergency department (ED) with suspected infection. 223 patients with suspected infection were enrolled for the study. Blood samples were collected on admission for measurement of biomarkers. Definitive diagnosis was obtained afterwards by analysis of digital medical records. Receiver operating characteristic (ROC) curve analysis was conducted to determine the diagnostic accuracy. Infection was confirmed in 200 patients, including 130 with non-complicated infection and 70 with sepsis. Median CRP, PCT and presepsin levels were significantly higher in patients with infection and sepsis. PCT was the biomarker with the highest performance for infection (ROC AUC: 0.910); for sepsis, PCT (ROC AUC: 0.815) and presepsin (ROC AUC: 0.775) shown a similar performance. Although presepsin is a valuable biomarker for diagnosis of infection and sepsis, its diagnostic accuracy in our study does not improve that of PCT. Its introduction in clinical practice is not justified. Copyright © 2016 Elsevier B.V. All rights reserved.

Clinical Evaluation of a Loop-Mediated Amplification Kit for Diagnosis of Imported Malaria

PubMed Central

Polley, Spencer D.; González, Iveth J.; Mohamed, Deqa; Daly, Rosemarie; Bowers, Kathy; Watson, Julie; Mewse, Emma; Armstrong, Margaret; Gray, Christen; Perkins, Mark D.; Bell, David; Kanda, Hidetoshi; Tomita, Norihiro; Kubota, Yutaka; Mori, Yasuyoshi; Chiodini, Peter L.; Sutherland, Colin J.

2013-01-01

Background. Diagnosis of malaria relies on parasite detection by microscopy or antigen detection; both fail to detect low-density infections. New tests providing rapid, sensitive diagnosis with minimal need for training would enhance both malaria diagnosis and malaria control activities. We determined the diagnostic accuracy of a new loop-mediated amplification (LAMP) kit in febrile returned travelers. Methods. The kit was evaluated in sequential blood samples from returned travelers sent for pathogen testing to a specialist parasitology laboratory. Microscopy was performed, and then malaria LAMP was performed using Plasmodium genus and Plasmodium falciparum–specific tests in parallel. Nested polymerase chain reaction (PCR) was performed on all samples as the reference standard. Primary outcome measures for diagnostic accuracy were sensitivity and specificity of LAMP results, compared with those of nested PCR. Results. A total of 705 samples were tested in the primary analysis. Sensitivity and specificity were 98.4% and 98.1%, respectively, for the LAMP P. falciparum primers and 97.0% and 99.2%, respectively, for the Plasmodium genus primers. Post hoc repeat PCR analysis of all 15 tests with discrepant results resolved 4 results in favor of LAMP, suggesting that the primary analysis had underestimated diagnostic accuracy. Conclusions. Malaria LAMP had a diagnostic accuracy similar to that of nested PCR, with a greatly reduced time to result, and was superior to expert microscopy. PMID:23633403

Macular versus Retinal Nerve Fiber Layer Parameters for Diagnosing Manifest Glaucoma: A Systematic Review of Diagnostic Accuracy Studies.

PubMed

Oddone, Francesco; Lucenteforte, Ersilia; Michelessi, Manuele; Rizzo, Stanislao; Donati, Simone; Parravano, Mariacristina; Virgili, Gianni

2016-05-01

Macular parameters have been proposed as an alternative to retinal nerve fiber layer (RNFL) parameters to diagnose glaucoma. Comparing the diagnostic accuracy of macular parameters, specifically the ganglion cell complex (GCC) and ganglion cell inner plexiform layer (GCIPL), with the accuracy of RNFL parameters for detecting manifest glaucoma is important to guide clinical practice and future research. Studies using spectral domain optical coherence tomography (SD OCT) and reporting macular parameters were included if they allowed the extraction of accuracy data for diagnosing manifest glaucoma, as confirmed with automated perimetry or a clinician's optic nerve head (ONH) assessment. Cross-sectional cohort studies and case-control studies were included. The QUADAS 2 tool was used to assess methodological quality. Only direct comparisons of macular versus RNFL parameters (i.e., in the same study) were conducted. Summary sensitivity and specificity of each macular or RNFL parameter were reported, and the relative diagnostic odds ratio (DOR) was calculated in hierarchical summary receiver operating characteristic (HSROC) models to compare them. Thirty-four studies investigated macular parameters using RTVue OCT (Optovue Inc., Fremont, CA) (19 studies, 3094 subjects), Cirrus OCT (Carl Zeiss Meditec Inc., Dublin, CA) (14 studies, 2164 subjects), or 3D Topcon OCT (Topcon, Inc., Tokyo, Japan) (4 studies, 522 subjects). Thirty-two of these studies allowed comparisons between macular and RNFL parameters. Studies generally reported sensitivities at fixed specificities, more commonly 0.90 or 0.95, with sensitivities of most best-performing parameters between 0.65 and 0.75. For all OCT devices, compared with RNFL parameters, macular parameters were similarly or slightly less accurate for detecting glaucoma at the highest reported specificity, which was confirmed in analyses at the lowest specificity. Included studies suffered from limitations, especially the case-control study design, which is known to overestimate accuracy. However, this flaw is less relevant as a source of bias in direct comparisons conducted within studies. With the use of OCT, RNFL parameters are still preferable to macular parameters for diagnosing manifest glaucoma, but the differences are small. Because of high heterogeneity, direct comparative or randomized studies of OCT devices or OCT parameters and diagnostic strategies are essential. Copyright © 2016 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.

Usefulness of 3-dimensional stereotactic surface projection FDG PET images for the diagnosis of dementia

PubMed Central

Kim, Jahae; Cho, Sang-Geon; Song, Minchul; Kang, Sae-Ryung; Kwon, Seong Young; Choi, Kang-Ho; Choi, Seong-Min; Kim, Byeong-Chae; Song, Ho-Chun

2016-01-01

Abstract To compare diagnostic performance and confidence of a standard visual reading and combined 3-dimensional stereotactic surface projection (3D-SSP) results to discriminate between Alzheimer disease (AD)/mild cognitive impairment (MCI), dementia with Lewy bodies (DLB), and frontotemporal dementia (FTD). [18F]fluorodeoxyglucose (FDG) PET brain images were obtained from 120 patients (64 AD/MCI, 38 DLB, and 18 FTD) who were clinically confirmed over 2 years follow-up. Three nuclear medicine physicians performed the diagnosis and rated diagnostic confidence twice; once by standard visual methods, and once by adding of 3D-SSP. Diagnostic performance and confidence were compared between the 2 methods. 3D-SSP showed higher sensitivity, specificity, accuracy, positive, and negative predictive values to discriminate different types of dementia compared with the visual method alone, except for AD/MCI specificity and FTD sensitivity. Correction of misdiagnosis after adding 3D-SSP images was greatest for AD/MCI (56%), followed by DLB (13%) and FTD (11%). Diagnostic confidence also increased in DLB (visual: 3.2; 3D-SSP: 4.1; P < 0.001), followed by AD/MCI (visual: 3.1; 3D-SSP: 3.8; P = 0.002) and FTD (visual: 3.5; 3D-SSP: 4.2; P = 0.022). Overall, 154/360 (43%) cases had a corrected misdiagnosis or improved diagnostic confidence for the correct diagnosis. The addition of 3D-SSP images to visual analysis helped to discriminate different types of dementia in FDG PET scans, by correcting misdiagnoses and enhancing diagnostic confidence in the correct diagnosis. Improvement of diagnostic accuracy and confidence by 3D-SSP images might help to determine the cause of dementia and appropriate treatment. PMID:27930593

Diagnostic validity of methods for assessment of swallowing sounds: a systematic review.

PubMed

Taveira, Karinna Veríssimo Meira; Santos, Rosane Sampaio; Leão, Bianca Lopes Cavalcante de; Neto, José Stechman; Pernambuco, Leandro; Silva, Letícia Korb da; De Luca Canto, Graziela; Porporatti, André Luís

2018-02-03

Oropharyngeal dysphagia is a highly prevalent comorbidity in neurological patients and presents a serious health threat, which may lead to outcomes of aspiration pneumonia, ranging from hospitalization to death. This assessment proposes a non-invasive, acoustic-based method to differentiate between individuals with and without signals of penetration and aspiration. This systematic review evaluated the diagnostic validity of different methods for assessment of swallowing sounds, when compared to Videofluroscopic of Swallowing Study (VFSS) to detect oropharyngeal dysphagia. Articles in which the primary objective was to evaluate the accuracy of swallowing sounds were searched in five electronic databases with no language or time limitations. Accuracy measurements described in the studies were transformed to construct receiver operating characteristic curves and forest plots with the aid of Review Manager v. 5.2 (The Nordic Cochrane Centre, Copenhagen, Denmark). The methodology of the selected studies was evaluated using the Quality Assessment Tool for Diagnostic Accuracy Studies-2. The final electronic search revealed 554 records, however only 3 studies met the inclusion criteria. The accuracy values (area under the curve) were 0.94 for microphone, 0.80 for Doppler, and 0.60 for stethoscope. Based on limited evidence and low methodological quality because few studies were included, with a small sample size, from all index testes found for this systematic review, Doppler showed excellent diagnostic accuracy for the discrimination of swallowing sounds, whereas microphone-reported good accuracy discrimination of swallowing sounds of dysphagic patients and stethoscope showed best screening test. Copyright © 2018 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. Published by Elsevier Editora Ltda. All rights reserved.

The Diagnostic Accuracy of Cytology for the Diagnosis of Hepatobiliary and Pancreatic Cancers.

PubMed

Al-Hajeili, Marwan; Alqassas, Maryam; Alomran, Astabraq; Batarfi, Bashaer; Basunaid, Bashaer; Alshail, Reem; Alaydarous, Shahad; Bokhary, Rana; Mosli, Mahmoud

2018-06-13

Although cytology testing is considered a valuable method to diagnose tumors that are difficult to access such as hepato-biliary-pancreatic (HBP) malignancies, its diagnostic accuracy remains unclear. We therefore aimed to investigate the diagnostic accuracy of cytology testing for HBP tumors. We performed a retrospective study of all cytology samples that were used to confirm radiologically detected HBP tumors between 2002 and 2016. The cytology techniques used in our center included fine needle aspiration (FNA), brush cytology, and aspiration of bile. Sensitivity, specificity, positive and negative predictive values, and likelihood ratios were calculated in comparison to histological confirmation. From a total of 133 medical records, we calculated an overall sensitivity of 76%, specificity of 74%, a negative likelihood ratio of 0.30, and a positive likelihood ratio of 2.9. Cytology was more accurate in diagnosing lesions of the liver (sensitivity 79%, specificity 57%) and biliary tree (sensitivity 100%, specificity 50%) compared to pancreatic (sensitivity 60%, specificity 83%) and gallbladder lesions (sensitivity 50%, specificity 85%). Cytology was more accurate in detecting primary cancers (sensitivity 77%, specificity 73%) when compared to metastatic cancers (sensitivity 73%, specificity 100%). FNA was the most frequently used cytological technique to diagnose HBP lesions (sensitivity 78.8%). Cytological testing is efficient in diagnosing HBP cancers, especially for hepatobiliary tumors. Given its relative simplicity, cost-effectiveness, and paucity of alternative diagnostic methods, cytology should still be considered as a first-line tool for diagnosing HBP malignancies. © 2018 S. Karger AG, Basel.

Compact Intraoperative MRI: Stereotactic Accuracy and Future Directions.

PubMed

Markowitz, Daniel; Lin, Dishen; Salas, Sussan; Kohn, Nina; Schulder, Michael

2017-01-01

Intraoperative imaging must supply data that can be used for accurate stereotactic navigation. This information should be at least as accurate as that acquired from diagnostic imagers. The aim of this study was to compare the stereotactic accuracy of an updated compact intraoperative MRI (iMRI) device based on a 0.15-T magnet to standard surgical navigation on a 1.5-T diagnostic scan MRI and to navigation with an earlier model of the same system. The accuracy of each system was assessed using a water-filled phantom model of the brain. Data collected with the new system were compared to those obtained in a previous study assessing the older system. The accuracy of the new iMRI was measured against standard surgical navigation on a 1.5-T MRI using T1-weighted (W) images. The mean error with the iMRI using T1W images was lower than that based on images from the 1.5-T scan (1.24 vs. 2.43 mm). T2W images from the newer iMRI yielded a lower navigation error than those acquired with the prior model (1.28 vs. 3.15 mm). Improvements in magnet design can yield progressive increases in accuracy, validating the concept of compact, low-field iMRI. Avoiding the need for registration between image and surgical space increases navigation accuracy. © 2017 S. Karger AG, Basel.

Diagnostic Accuracy of an MRI Protocol of the Knee Accelerated Through Parallel Imaging in Correlation to Arthroscopy.

PubMed

Schnaiter, Johannes Walter; Roemer, Frank; McKenna-Kuettner, Axel; Patzak, Hans-Joachim; May, Matthias Stefan; Janka, Rolf; Uder, Michael; Wuest, Wolfgang

2018-03-01

 Parallel imaging allows for a considerable shortening of examination times. Limited data is available about the diagnostic accuracy of an accelerated knee MRI protocol based on parallel imaging evaluating all knee joint compartments in a large patient population compared to arthroscopy.  162 consecutive patients with a knee MRI (1.5 T, Siemens Aera) and arthroscopy were included. The total MRI scan time was less than 9 minutes. Meniscus and cartilage injuries, cruciate ligament lesions, loose joint bodies and medial patellar plicae were evaluated. Sensitivity (SE), specificity (SP), positive predictive value (PPV), and negative predictive value (NPV), as well as diagnostic accuracy were determined.  For the medial meniscus, the values were: SE 97 %, SP 88 %, PPV 94 %, and NPV 94 %. For the lateral meniscus the values were: SE 77 %, SP 99 %, PPV 98 %, and NPV 89 %. For cartilage injuries the values were: SE 72 %, SP 80 %, PPV 86 %, and NPV 61 %. For the anterior cruciate ligament the values were: SE 90 %, SP 94 %, PPV 77 %, and NPV 98 %, while all values were 100 % for the posterior cruciate ligament. For loose bodies the values were: SE 48 %, SP 96 %, PPV 62 %, and NPV 93 %, and for the medial patellar plicae the values were: SE 57 %, SP 88 %, PPV 18 %, and NPV 98 %.  A knee MRI examination with parallel imaging and a scan time of less than 9 minutes delivers reliable results with high diagnostic accuracy.   · An accelerated knee MRI protocol with parallel imaging allows for high diagnostic accuracy.. · Especially meniscal and cruciate ligament injuries are well depicted.. · Cartilage injuries seem to be overestimated.. · Schnaiter JW, Roemer F, McKenna-Kuettner A et al. Diagnostic Accuracy of an MRI Protocol of the Knee Accelerated Through Parallel Imaging in Correlation to Arthroscopy. Fortschr Röntgenstr 2018; 190: 265 - 272. © Georg Thieme Verlag KG Stuttgart · New York.

Diagnostic Accuracy of Computed Tomography Angiography as Compared to Conventional Angiography in Patients Undergoing Noncoronary Cardiac Surgery

PubMed Central

Joshi, Hasit; Shah, Ronak; Prajapati, Jayesh; Bhangdiya, Vipin; Shah, Jayal; Kandre, Yogini; Shah, Komal

2016-01-01

Objective: To compare the diagnostic accuracy of multi-slice computed tomography (MSCT) angiography with conventional angiography in patients undergoing major noncoronary cardiac surgeries. Materials and Methods: We studied fifty major noncoronary cardiac surgery patients scheduled for invasive coronary angiography, 29 (58%) female and 21 (42%) male. Inclusion criteria of the study were age of the patients ≥40 years, having low or intermediate probability of coronary artery disease (CAD), left ventricular ejection fraction (LVEF) >35%, and patient giving informed consent for undergoing MSCT and conventional coronary angiography. The patients with LVEF <35%, high pretest probability of CAD, and hemodynamically unstable were excluded from the study. Results: The diagnostic accuracy of CT coronary angiography was evaluated regarding true positive, true negative values. The overall sensitivity and specificity of CT angiography technique was 100% (95% confidence interval [CI]: 39.76%–100%) and 91.30% (95% CI: 79.21%–97.58%). The positive (50%; 95% CI: 15.70%–84.30%) and negative predictive values (100%; 95% CI: 91.59%–100%) of CT angiography were also fairly high in these patients. Conclusion: Our study suggests that this non-invasive technique may improve perioperative risk stratification in patients undegoing non-cardiac surgery. PMID:27867455

Multiple performance measures are needed to evaluate triage systems in the emergency department.

PubMed

Zachariasse, Joany M; Nieboer, Daan; Oostenbrink, Rianne; Moll, Henriëtte A; Steyerberg, Ewout W

2018-02-01

Emergency department triage systems can be considered prediction rules with an ordinal outcome, where different directions of misclassification have different clinical consequences. We evaluated strategies to compare the performance of triage systems and aimed to propose a set of performance measures that should be used in future studies. We identified performance measures based on literature review and expert knowledge. Their properties are illustrated in a case study evaluating two triage modifications in a cohort of 14,485 pediatric emergency department visits. Strengths and weaknesses of the performance measures were systematically appraised. Commonly reported performance measures are measures of statistical association (34/60 studies) and diagnostic accuracy (17/60 studies). The case study illustrates that none of the performance measures fulfills all criteria for triage evaluation. Decision curves are the performance measures with the most attractive features but require dichotomization. In addition, paired diagnostic accuracy measures can be recommended for dichotomized analysis, and the triage-weighted kappa and Nagelkerke's R 2 for ordinal analyses. Other performance measures provide limited additional information. When comparing modifications of triage systems, decision curves and diagnostic accuracy measures should be used in a dichotomized analysis, and the triage-weighted kappa and Nagelkerke's R 2 in an ordinal approach. Copyright © 2017 Elsevier Inc. All rights reserved.

The comparative accuracy of rapid diagnostic test with microscopy to diagnose malaria in subdistrict lima puluh batubara regency North Sumatera province

NASA Astrophysics Data System (ADS)

Rezeki, S.; Pasaribu, A. P.

2018-03-01

Indonesia is the country where malaria is still the most common population problem. The high rate of mortality and morbidity occurred due to delays in diagnosis whichis strongly influenced by the availability of diagnostic tools and personnel with required laboratory skill. This diagnostic study aims to compare the accuracy of a Rapid Diagnostic Test (RDT) without skill requirement, to agold standard microscopic method for malaria diagnosis. The study was conducted in Subdistrict Lima Puluh North Sumatera Province from December 2015 to January 2016. The subject was taken cross-sectionally from a population with characteristics typically found in malaria patients in Subdistrict Lima Puluh. The result showed a sensitivity of 100% and a specificity of 72.4% with a positive predictive value of 89.9% and a negative predictive value of 100%; the negative likelihood ratio is 0 and the positive likelihood ratio of 27.6 for Parascreen. This research indicates that Parascreen had a high sensitivity and specificity and may be consideredas an alternative for the diagnosis of malaria in Subdistrict Lima Puluh North Sumatera Province especially in areas where no skilled microscopist is available.

Thoracic injury rule out criteria and NEXUS chest in predicting the risk of traumatic intra-thoracic injuries: A diagnostic accuracy study.

PubMed

Safari, Saeed; Radfar, Fatemeh; Baratloo, Alireza

2018-05-01

This study aimed to compare the diagnostic accuracy of NEXUS chest and Thoracic Injury Rule out criteria (TIRC) models in predicting the risk of intra-thoracic injuries following blunt multiple trauma. In this diagnostic accuracy study, using the 2 mentioned models, blunt multiple trauma patients over the age of 15 years presenting to emergency department were screened regarding the presence of intra-thoracic injuries that are detectable via chest x-ray and screening performance characteristics of the models were compared. In this study, 3118 patients with the mean (SD) age of 37.4 (16.9) years were studied (57.4% male). Based on TIRC and NEXUS chest, respectively, 1340 (43%) and 1417 (45.4%) patients were deemed in need of radiography performance. Sensitivity, specificity, and positive and negative predictive values of TIRC were 98.95%, 62.70%, 21.19% and 99.83%. These values were 98.61%, 59.94%, 19.97% and 99.76%, for NEXUS chest, respectively. Accuracy of TIRC and NEXUS chest models were 66.04 (95% CI: 64.34-67.70) and 63.50 (95% CI: 61.78-65.19), respectively. TIRC and NEXUS chest models have proper and similar sensitivity in prediction of blunt traumatic intra-thoracic injuries that are detectable via chest x-ray. However, TIRC had a significantly higher specificity in this regard. Copyright © 2018 Elsevier Ltd. All rights reserved.

Accuracy of Immunofluorescence in the Diagnosis of Primary Ciliary Dyskinesia

PubMed Central

Frost, Emily; Dixon, Mellisa; Ollosson, Sarah; Kilpin, Kate; Patel, Mitali; Scully, Juliet; Rogers, Andrew V.; Mitchison, Hannah M.; Bush, Andrew; Hogg, Claire

2017-01-01

Rationale: The standard approach to diagnosis of primary ciliary dyskinesia (PCD) in the United Kingdom consists of assessing ciliary function by high-speed microscopy and ultrastructure by election microscopy, but equipment and expertise is not widely available internationally. The identification of biallelic disease-causing mutations is also diagnostic, but many disease-causing genes are unknown, and testing is not widely available outside the United States. Fluorescent antibodies to ciliary proteins are used to validate research genetic studies, but diagnostic utility in this disease has not been systematically evaluated. Objectives: To determine utility of a panel of six fluorescent labeled antibodies as a diagnostic tool for PCD. Methods: The study used immunofluorescent labeling of nasal brushings from a discovery cohort of 35 patients diagnosed with PCD by ciliary ultrastructure, and a diagnostic accuracy cohort of 386 patients referred with symptoms suggestive of disease. The results were compared with diagnostic outcome. Measurements and Main Results: Immunofluorescence correctly identified mislocalized or absent staining in 100% of the discovery cohort. In the diagnostic cohort immunofluorescence successfully identified 22 of 25 patients with PCD and normal staining in all 252 in whom PCD was considered highly unlikely. In addition, immunofluorescence provided a result in 55% (39) of cases that were previously inconclusive. Immunofluorescence results were available within 14 days, costing $187 per sample compared with electron microscopy (27 days; cost $1,452). Conclusions: Immunofluorescence is a highly specific diagnostic test for PCD, and it improves the speed and availability of diagnostic testing. However, sensitivity is limited and immunofluorescence is not suitable as a stand-alone test. PMID:28199173

Improved image quality and diagnostic potential using ultra-high-resolution computed tomography of the lung with small scan FOV: A prospective study

PubMed Central

Wang, Yali; Hamal, Preeti; You, Xiaofang; Mao, Haixia; Li, Fei; Sun, Xiwen

2017-01-01

The aim of this study was to assess whether CT imaging using an ultra-high-resolution CT (UHRCT) scan with a small scan field of view (FOV) provides higher image quality and helps to reduce the follow-up period compared with a conventional high-resolution CT (CHRCT) scan. We identified patients with at least one pulmonary nodule at our hospital from July 2015 to November 2015. CHRCT and UHRCT scans were conducted in all enrolled patients. Three experienced radiologists evaluated the image quality using a 5-point score and made diagnoses. The paired images were displayed side by side in a random manner and annotations of scan information were removed. The following parameters including image quality, diagnostic confidence of radiologists, follow-up recommendations and diagnostic accuracy were assessed. A total of 52 patients (62 nodules) were included in this study. UHRCT scan provides a better image quality regarding the margin of nodules and solid internal component compared to that of CHRCT (P < 0.05). Readers have higher diagnostic confidence based on the UHRCT images than of CHRCT images (P<0.05). The follow-up recommendations were significantly different between UHRCT and CHRCT images (P<0.05). Compared with the surgical pathological findings, UHRCT had a relative higher diagnostic accuracy than CHRCT (P > 0.05). These findings suggest that the UHRCT prototype scanner provides a better image quality of subsolid nodules compared to CHRCT and contributes significantly to reduce the patients' follow-up period. PMID:28231320

Contrast-enhanced small-animal PET/CT in cancer research: strong improvement of diagnostic accuracy without significant alteration of quantitative accuracy and NEMA NU 4-2008 image quality parameters.

PubMed

Lasnon, Charline; Quak, Elske; Briand, Mélanie; Gu, Zheng; Louis, Marie-Hélène; Aide, Nicolas

2013-01-17

The use of iodinated contrast media in small-animal positron emission tomography (PET)/computed tomography (CT) could improve anatomic referencing and tumor delineation but may introduce inaccuracies in the attenuation correction of the PET images. This study evaluated the diagnostic performance and accuracy of quantitative values in contrast-enhanced small-animal PET/CT (CEPET/CT) as compared to unenhanced small animal PET/CT (UEPET/CT). Firstly, a NEMA NU 4-2008 phantom (filled with 18F-FDG or 18F-FDG plus contrast media) and a homemade phantom, mimicking an abdominal tumor surrounded by water or contrast media, were used to evaluate the impact of iodinated contrast media on the image quality parameters and accuracy of quantitative values for a pertinent-sized target. Secondly, two studies in 22 abdominal tumor-bearing mice and rats were performed. The first animal experiment studied the impact of a dual-contrast media protocol, comprising the intravenous injection of a long-lasting contrast agent mixed with 18F-FDG and the intraperitoneal injection of contrast media, on tumor delineation and the accuracy of quantitative values. The second animal experiment compared the diagnostic performance and quantitative values of CEPET/CT versus UEPET/CT by sacrificing the animals after the tracer uptake period and imaging them before and after intraperitoneal injection of contrast media. There was minimal impact on IQ parameters (%SDunif and spillover ratios in air and water) when the NEMA NU 4-2008 phantom was filled with 18F-FDG plus contrast media. In the homemade phantom, measured activity was similar to true activity (-0.02%) and overestimated by 10.30% when vials were surrounded by water or by an iodine solution, respectively. The first animal experiment showed excellent tumor delineation and a good correlation between small-animal (SA)-PET and ex vivo quantification (r2 = 0.87, P < 0.0001). The second animal experiment showed a good correlation between CEPET/CT and UEPET/CT quantitative values (r2 = 0.99, P < 0.0001). Receiver operating characteristic analysis demonstrated better diagnostic accuracy of CEPET/CT versus UEPET/CT (senior researcher, area under the curve (AUC) 0.96 versus 0.77, P = 0.004; junior researcher, AUC 0.78 versus 0.58, P = 0.004). The use of iodinated contrast media for small-animal PET imaging significantly improves tumor delineation and diagnostic performance, without significant alteration of SA-PET quantitative accuracy and NEMA NU 4-2008 IQ parameters.

Diagnostic accuracy of sequential co-registered PET+MR in comparison to PET/CT in local thoracic staging of malignant pleural mesothelioma.

PubMed

Martini, Katharina; Meier, Andreas; Opitz, Isabelle; Weder, Walter; Veit-Haibach, Patrick; Stahel, Rolf A; Frauenfelder, Thomas

2016-04-01

To investigate the diagnostic accuracy of sequential co-registered PET+MR (PET+MR) for local staging of malignant pleural mesothelioma (MPM) compared to PET/CT. In a prospective clinical trial 34 consecutive patients (median age 66 years; range 40-79 years; 1 female, 33 male) with known MPM, who underwent PET/CT and PET+MR exams for either staging or re-staging/follow-up were evaluated. Imaging was conducted using a tri-modality PET/CT-MR set-up (Discovery PET/CT 690, 3T Discovery MR 750w, both GE Healthcare, Waukesha, WI, USA). In 26 cases histopathology served as standard of reference. Two independent readers evaluated images for T and N stage, confidence level (sure to unsure; 1-3) and subjective overall image quality (very good to non-diagnostic; 1-4). Inter-observer agreement of T and N stages (Cohen's kappa) and interclass correlation coefficient (ICC) between PET/CT vs. PET+MR was calculated. Inter observer agreement for evaluation of T and N Stage in PET/CT images was excellent (k=0.844 and k=0.824, respectively), whereas PET+MR imaging showed substantial agreement in T and N stage (k=0.729 and k=0.691, respectively). The ICC of PET/CT vs. PET+MR for evaluation of both, T and N Stage, was excellent (ICC=0.951 and ICC=0.93, respectively). Diagnostic confidence was scored significantly higher in PET+MR compared to PET/CT (mean score=1.66 and 1.93, respectively; p=0.004). Image quality was diagnostic for all image series. Comparing pT and pN stage vs cT and cN stage (n=26 cases), both imaging modalities showed excellent agreement for T stage (ICCPET+MR=0.888 vs. ICCPET/CT=0.853, respectively) and substantial to moderate agreement for N stage (ICCPET+MR=0.683 vs. ICC=0.595PET/CT, respectively). Our findings suggest that diagnostic accuracy of PET+MR is comparable to PET/CT for local staging of MPM, whereas radiologists felt significantly more confident staging PET+MR compared to PET/CT images (p=0003), using dedicated sequences. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

The diagnostic accuracy of multi-frequency bioelectrical impedance analysis in diagnosing dehydration after stroke.

PubMed

Kafri, Mohannad W; Myint, Phyo Kway; Doherty, Danielle; Wilson, Alexander Hugh; Potter, John F; Hooper, Lee

2013-07-10

Non-invasive methods for detecting water-loss dehydration following acute stroke would be clinically useful. We evaluated the diagnostic accuracy of multi-frequency bioelectrical impedance analysis (MF-BIA) against reference standards serum osmolality and osmolarity. Patients admitted to an acute stroke unit were recruited. Blood samples for electrolytes and osmolality were taken within 20 minutes of MF-BIA. Total body water (TBW%), intracellular (ICW%) and extracellular water (ECW%), as percentages of total body weight, were calculated by MF-BIA equipment and from impedance measures using published equations for older people. These were compared to hydration status (based on serum osmolality and calculated osmolarity). The most promising Receiver Operating Characteristics curves were plotted. 27 stroke patients were recruited (mean age 71.3, SD10.7). Only a TBW% cut-off at 46% was consistent with current dehydration (serum osmolality >300 mOsm/kg) and TBW% at 47% impending dehydration (calculated osmolarity ≥295-300 mOsm/L) with sensitivity and specificity both >60%. Even here diagnostic accuracy of MF-BIA was poor, a third of those with dehydration were wrongly classified as hydrated and a third classified as dehydrated were well hydrated. Secondary analyses assessing diagnostic accuracy of TBW% for men and women separately, and using TBW as a percentage of lean body mass showed some promise, but did not provide diagnostically accurate measures across the population. MF-BIA appears ineffective at diagnosing water-loss dehydration after stroke and cannot be recommended as a test for dehydration, but separating assessment by sex, and using TBW as a percentage of lean body weight may warrant further investigation.

Diagnostic accuracy for major depression in multiple sclerosis using self-report questionnaires

PubMed Central

Fischer, Anja; Fischer, Marcus; Nicholls, Robert A; Lau, Stephanie; Poettgen, Jana; Patas, Kostas; Heesen, Christoph; Gold, Stefan M

2015-01-01

Objective Multiple sclerosis and major depressive disorder frequently co-occur but depression often remains undiagnosed in this population. Self-rated depression questionnaires are a good option where clinician-based standardized diagnostics are not feasible. However, there is a paucity of data on diagnostic accuracy of self-report measures for depression in multiple sclerosis (MS). Moreover, head-to-head comparisons of common questionnaires are largely lacking. This could be particularly relevant for high-risk patients with depressive symptoms. Here, we compare the diagnostic accuracy of the Beck Depression Inventory (BDI) and 30-item version of the Inventory of Depressive Symptomatology Self-Rated (IDS-SR30) for major depressive disorder (MSS) against diagnosis by a structured clinical interview. Methods Patients reporting depressive symptoms completed the BDI, the IDS-SR30 and underwent diagnostic assessment (Mini International Neuropsychiatric Interview, M.I.N.I.). Receiver-Operating Characteristic analyses were performed, providing error estimates and false-positive/negative rates of suggested thresholds. Results Data from n = 31 MS patients were available. BDI and IDS-SR30 total score were significantly correlated (r = 0.82). The IDS-SR30total score, cognitive subscore, and BDI showed excellent to good accuracy (area under the curve (AUC) 0.86, 0.91, and 0.85, respectively). Conclusion Both the IDS-SR30 and the BDI are useful to quantify depressive symptoms showing good sensitivity and specificity. The IDS-SR30 cognitive subscale may be useful as a screening tool and to quantify affective/cognitive depressive symptomatology. PMID:26445703

Use of diagnostic accuracy as a metric for evaluating laboratory proficiency with microarray assays using mixed-tissue RNA reference samples.

PubMed

Pine, P S; Boedigheimer, M; Rosenzweig, B A; Turpaz, Y; He, Y D; Delenstarr, G; Ganter, B; Jarnagin, K; Jones, W D; Reid, L H; Thompson, K L

2008-11-01

Effective use of microarray technology in clinical and regulatory settings is contingent on the adoption of standard methods for assessing performance. The MicroArray Quality Control project evaluated the repeatability and comparability of microarray data on the major commercial platforms and laid the groundwork for the application of microarray technology to regulatory assessments. However, methods for assessing performance that are commonly applied to diagnostic assays used in laboratory medicine remain to be developed for microarray assays. A reference system for microarray performance evaluation and process improvement was developed that includes reference samples, metrics and reference datasets. The reference material is composed of two mixes of four different rat tissue RNAs that allow defined target ratios to be assayed using a set of tissue-selective analytes that are distributed along the dynamic range of measurement. The diagnostic accuracy of detected changes in expression ratios, measured as the area under the curve from receiver operating characteristic plots, provides a single commutable value for comparing assay specificity and sensitivity. The utility of this system for assessing overall performance was evaluated for relevant applications like multi-laboratory proficiency testing programs and single-laboratory process drift monitoring. The diagnostic accuracy of detection of a 1.5-fold change in signal level was found to be a sensitive metric for comparing overall performance. This test approaches the technical limit for reliable discrimination of differences between two samples using this technology. We describe a reference system that provides a mechanism for internal and external assessment of laboratory proficiency with microarray technology and is translatable to performance assessments on other whole-genome expression arrays used for basic and clinical research.

Diagnostic value of 3.0T (1)H MRS with choline-containing compounds ratio (∆CCC) in primary malignant hepatic tumors.

PubMed

Zhang, Li; Zhao, Xinming; Ouyang, Han; Wang, Shuang; Zhou, Chunwu

2016-08-22

The purpose of this study was to investigate the diagnostic value of 3.0-T (1)H magnetic resonance spectroscopy ((1)H MRS) in primary malignant hepatic tumors and to compare the effects of (1)H MRS on the diagnostic accuracy of liver-occupying lesions between junior and experienced radiologists. This study included 50 healthy volunteers and 40 consecutive patients (50 lesions). Informed consent was obtained from each subject. Images were obtained on clinical whole-body 3.0-T MR system. Point -Resolved Spectroscopy was used to obtain the spectroscopy image. All conventional images were reviewed blindly by junior radiologist and experienced radiologist, respectively. The choline-containing compounds peak area (CCC-A) was measured with SAGE software, and the choline-containing compound ratio (∆CCC) was calculated. The efficacy of CCC-A and ∆CCC in the diagnosis of primary malignant hepatic tumors was determined by plotting receiver operating characteristic (ROC) curves. We also compared the effects of MRS on the diagnostic accuracy of liver-occupying lesions with junior and experienced radiologist. A significant increase in mean CCC-A was observed in malignant tumors compared with benign tumors. The ROC curve showed ∆CCC had a high discriminatory ability in diagnosing primary malignant hepatic tumors with a sensitivity and specificity of 94.3 and 93.3 %, respectively. The ∆CCC area under the curve (AUC) was 0.97 that was larger than that of both junior and experienced radiologist, while the significantly statistical difference was only obtained between ∆CCC and junior radiologist (P = 0.01). (1)H MRS with ∆CCC demonstrates good efficacy in diagnosing primary malignant hepatic tumors. The technique improves the accuracy of diagnosing liver-occupying lesions, particularly for junior radiologists.

Using Meta-Analysis to Inform the Design of Subsequent Studies of Diagnostic Test Accuracy

ERIC Educational Resources Information Center

Hinchliffe, Sally R.; Crowther, Michael J.; Phillips, Robert S.; Sutton, Alex J.

2013-01-01

An individual diagnostic accuracy study rarely provides enough information to make conclusive recommendations about the accuracy of a diagnostic test; particularly when the study is small. Meta-analysis methods provide a way of combining information from multiple studies, reducing uncertainty in the result and hopefully providing substantial…

STARD 2015 guidelines for reporting diagnostic accuracy studies: explanation and elaboration

PubMed Central

Cohen, Jérémie F; Korevaar, Daniël A; Altman, Douglas G; Bruns, David E; Gatsonis, Constantine A; Hooft, Lotty; Irwig, Les; Levine, Deborah; Reitsma, Johannes B; de Vet, Henrica C W; Bossuyt, Patrick M M

2016-01-01

Diagnostic accuracy studies are, like other clinical studies, at risk of bias due to shortcomings in design and conduct, and the results of a diagnostic accuracy study may not apply to other patient groups and settings. Readers of study reports need to be informed about study design and conduct, in sufficient detail to judge the trustworthiness and applicability of the study findings. The STARD statement (Standards for Reporting of Diagnostic Accuracy Studies) was developed to improve the completeness and transparency of reports of diagnostic accuracy studies. STARD contains a list of essential items that can be used as a checklist, by authors, reviewers and other readers, to ensure that a report of a diagnostic accuracy study contains the necessary information. STARD was recently updated. All updated STARD materials, including the checklist, are available at http://www.equator-network.org/reporting-guidelines/stard. Here, we present the STARD 2015 explanation and elaboration document. Through commented examples of appropriate reporting, we clarify the rationale for each of the 30 items on the STARD 2015 checklist, and describe what is expected from authors in developing sufficiently informative study reports. PMID:28137831

Accuracy of imaging methods for detection of bone tissue invasion in patients with oral squamous cell carcinoma

PubMed Central

Uribe, S; Rojas, LA; Rosas, CF

2013-01-01

The objective of this review is to evaluate the diagnostic accuracy of imaging methods for detection of mandibular bone tissue invasion by squamous cell carcinoma (SCC). A systematic review was carried out of studies in MEDLINE, SciELO and ScienceDirect, published between 1960 and 2012, in English, Spanish or German, which compared detection of mandibular bone tissue invasion via different imaging tests against a histopathology reference standard. Sensitivity and specificity data were extracted from each study. The outcome measure was diagnostic accuracy. We found 338 articles, of which 5 fulfilled the inclusion criteria. Tests included were: CT (four articles), MRI (four articles), panoramic radiography (one article), positron emission tomography (PET)/CT (one article) and cone beam CT (CBCT) (one article). The quality of articles was low to moderate and the evidence showed that all tests have a high diagnostic accuracy for detection of mandibular bone tissue invasion by SCC, with sensitivity values of 94% (MRI), 91% (CBCT), 83% (CT) and 55% (panoramic radiography), and specificity values of 100% (CT, MRI, CBCT), 97% (PET/CT) and 91.7% (panoramic radiography). Available evidence is scarce and of only low to moderate quality. However, it is consistently shown that current imaging methods give a moderate to high diagnostic accuracy for the detection of mandibular bone tissue invasion by SCC. Recommendations are given for improving the quality of future reports, in particular provision of a detailed description of the patients' conditions, the imaging instrument and both imaging and histopathological invasion criteria. PMID:23420854

Role of Arrival Time Difference Between Lesions and Lung Tissue on Contrast-Enhanced Sonography in the Differential Diagnosis of Subpleural Pulmonary Lesions.

PubMed

Bai, Jing; Yang, Wei; Wang, Song; Guan, Rui-Hong; Zhang, Hui; Fu, Jing-Jing; Wu, Wei; Yan, Kun

2016-07-01

The purpose of this study was to explore the diagnostic value of the arrival time difference between lesions and surrounding lung tissue on contrast-enhanced sonography of subpleural pulmonary lesions. A total of 110 patients with subpleural pulmonary lesions who underwent both conventional and contrast-enhanced sonography and had a definite diagnosis were enrolled. After contrast agent injection, the arrival times in the lesion, lung, and chest wall were recorded. The arrival time differences between various tissues were also calculated. Statistical analysis showed a significant difference in the lesion arrival time, the arrival time difference between the lesion and lung, and the arrival time difference between the chest wall and lesion (all P < .001) for benign and malignant lesions. Receiver operating characteristic curve analysis revealed that the optimal diagnostic criterion was the arrival time difference between the lesion and lung, and that the best cutoff point was 2.5 seconds (later arrival signified malignancy). This new diagnostic criterion showed superior diagnostic accuracy (97.1%) compared to conventional diagnostic criteria. The individualized diagnostic method based on an arrival time comparison using contrast-enhanced sonography had high diagnostic accuracy (97.1%) with good feasibility and could provide useful diagnostic information for subpleural pulmonary lesions.

Diagnostic Tools for Acute Anterior Cruciate Ligament Injury: GNRB, Lachman Test, and Telos.

PubMed

Ryu, Seung Min; Na, Ho Dong; Shon, Oog Jin

2018-06-01

The purpose of this study is to compare the accuracy of the GNRB arthrometer (Genourob), Lachman test, and Telos device (GmbH) in acute anterior cruciate ligament (ACL) injuries and to evaluate the accuracy of each diagnostic tool according to the length of time from injury to examination. From September 2015 to September 2016, 40 cases of complete ACL rupture were reviewed. We divided the time from injury to examination into three periods of 10 days each and analyzed the diagnostic tools according to the time frame. An analysis of the area under the curve (AUC) of a receiver operating characteristic curve showed that all diagnostic tools were fairly informative. The GNRB showed a higher AUC than other diagnostic tools. In 10 cases assessed within 10 days after injury, the GNRB showed statistically significant side-to-side difference in laxity (p＜0.001), whereas the Telos test and Lachman test did not show significantly different laxity (p=0.541 and p=0.413, respectively). All diagnostic values of the GNRB were better than other diagnostic tools in acute ACL injuries. The GNRB was more effective in acute ACL injuries examined within 10 days of injury. The GNRB arthrometer can be a useful diagnostic tool for acute ACL injuries.

The STARD Statement for Reporting Diagnostic Accuracy Studies: Application to the History and Physical Examination

PubMed Central

Rennie, Drummond; Bossuyt, Patrick M. M.

2008-01-01

Summary Objective The Standards for Reporting of Diagnostic Accuracy (STARD) statement provided guidelines for investigators conducting diagnostic accuracy studies. We reviewed each item in the statement for its applicability to clinical examination diagnostic accuracy research, viewing each discrete aspect of the history and physical examination as a diagnostic test. Setting Nonsystematic review of the STARD statement. Interventions Two former STARD Group participants and 1 editor of a journal series on clinical examination research reviewed each STARD item. Suggested interpretations and comments were shared to develop consensus. Measurements and Main Results The STARD Statement applies generally well to clinical examination diagnostic accuracy studies. Three items are the most important for clinical examination diagnostic accuracy studies, and investigators should pay particular attention to their requirements: describe carefully the patient recruitment process, describe participant sampling and address if patients were from a consecutive series, and describe whether the clinicians were masked to the reference standard tests and whether the interpretation of the reference standard test was masked to the clinical examination components or overall clinical impression. The consideration of these and the other STARD items in clinical examination diagnostic research studies would improve the quality of investigations and strengthen conclusions reached by practicing clinicians. Conclusions The STARD statement provides a very useful framework for diagnostic accuracy studies. The group correctly anticipated that there would be nuances applicable to studies of the clinical examination. We offer guidance that should enhance their usefulness to investigators embarking on original studies of a patient’s history and physical examination. PMID:18347878

Diagnostic accuracy of the Thessaly test, standardised clinical history and other clinical examination tests (Apley's, McMurray's and joint line tenderness) for meniscal tears in comparison with magnetic resonance imaging diagnosis.

PubMed

Blyth, Mark; Anthony, Iain; Francq, Bernard; Brooksbank, Katriona; Downie, Paul; Powell, Andrew; Jones, Bryn; MacLean, Angus; McConnachie, Alex; Norrie, John

2015-08-01

Reliable non-invasive diagnosis of meniscal tears is difficult. Magnetic resonance imaging (MRI) is often used but is expensive and incidental findings are problematic. There are a number of physical examination tests for the diagnosis of meniscal tears that are simple, cheap and non-invasive. To determine the diagnostic accuracy of the Thessaly test and to determine if the Thessaly test (alone or in combination with other physical tests) can obviate the need for further investigation by MRI or arthroscopy for patients with a suspected meniscal tear. Single-centre prospective diagnostic accuracy study. Although the study was performed in a secondary care setting, it was designed to replicate the results that would have been achieved in a primary care setting. Two cohorts of patients were recruited: patients with knee pathology (n = 292) and a control cohort with no knee pathology (n = 75). Sensitivity, specificity and diagnostic accuracy of the Thessaly test in determining the presence of meniscal tears. Participants were assessed by both a primary care clinician and a musculoskeletal clinician. Both clinicians performed the Thessaly test, McMurray's test, Apley's test, joint line tenderness test and took a standardised clinical history from the patient. The Thessaly test had a sensitivity of 0.66, a specificity of 0.39 and a diagnostic accuracy of 54% when utilised by primary care clinicians. This compared with a sensitivity of 0.62, a specificity of 0.55 and diagnostic accuracy of 59% when used by musculoskeletal clinicians. The diagnostics accuracy of the other tests when used by primary care clinicians was 54% for McMurray's test, 53% for Apley's test, 54% for the joint line tenderness test and 55% for clinical history. For primary care clinicians, age and past history of osteoarthritis were both significant predictors of MRI diagnosis of meniscal tears. For musculoskeletal clinicians age and a positive diagnosis of meniscal tears on clinical history taking were significant predictors of MRI diagnosis. No physical tests were significant predictors of MRI diagnosis in our multivariate models. The specificity of MRI diagnosis was tested in subgroup of patients who went on to have a knee arthroscopy and was found to be low [0.53 (95% confidence interval 0.28 to 0.77)], although the sensitivity was 1.0. The Thessaly test was no better at diagnosing meniscal tears than other established physical tests. The sensitivity, specificity and diagnostic accuracy of all physical tests was too low to be of routine clinical value as an alternative to MRI. Caution needs to be exercised in the indiscriminate use of MRI scanning in the identification of meniscal tears in the diagnosis of the painful knee, due to the low specificity seen in the presence of concomitant knee pathology. Further research is required to determine the true diagnostic accuracy and cost-effectiveness of MRI for the detection of meniscal tears. Current Controlled Trial ISRCTN43527822. The National Institute for Health Research Health Technology Assessment programme.

Comparative analysis of diagnostic performance, feasibility and cost of different test-methods for thyroid nodules with indeterminate cytology

PubMed Central

Sciacchitano, Salvatore; Lavra, Luca; Ulivieri, Alessandra; Magi, Fiorenza; De Francesco, Gian Paolo; Bellotti, Carlo; Salehi, Leila B.; Trovato, Maria; Drago, Carlo; Bartolazzi, Armando

2017-01-01

Since it is impossible to recognize malignancy at fine needle aspiration (FNA) cytology in indeterminate thyroid nodules, surgery is recommended for all of them. However, cancer rate at final histology is <30%. Many different test-methods have been proposed to increase diagnostic accuracy in such lesions, including Galectin-3-ICC (GAL-3-ICC), BRAF mutation analysis (BRAF), Gene Expression Classifier (GEC) alone and GEC+BRAF, mutation/fusion (M/F) panel, alone, M/F panel+miRNA GEC, and M/F panel by next generation sequencing (NGS), FDG-PET/CT, MIBI-Scan and TSHR mRNA blood assay. We performed systematic reviews and meta-analyses to compare their features, feasibility, diagnostic performance and cost. GEC, GEC+BRAF, M/F panel+miRNA GEC and M/F panel by NGS were the best in ruling-out malignancy (sensitivity = 90%, 89%, 89% and 90% respectively). BRAF and M/F panel alone and by NGS were the best in ruling-in malignancy (specificity = 100%, 93% and 93%). The M/F by NGS showed the highest accuracy (92%) and BRAF the highest diagnostic odds ratio (DOR) (247). GAL-3-ICC performed well as rule-out (sensitivity = 83%) and rule-in test (specificity = 85%), with good accuracy (84%) and high DOR (27) and is one of the cheapest (113 USD) and easiest one to be performed in different clinical settings. In conclusion, the more accurate molecular-based test-methods are still expensive and restricted to few, highly specialized and centralized laboratories. GAL-3-ICC, although limited by some false negatives, represents the most suitable screening test-method to be applied on a large-scale basis in the diagnostic algorithm of indeterminate thyroid lesions. PMID:28472764

Diagnostic accuracy of the Patient Health Questionnaire-9 for assessment of depression in type II diabetes mellitus and/or coronary heart disease in primary care.

PubMed

van der Zwaan, G Lennart; van Dijk, Susan E M; Adriaanse, Marcel C; van Marwijk, Harm W J; van Tulder, Maurits W; Pols, Alide D; Bosmans, Judith E

2016-01-15

Depression is common among type 2 diabetes mellitus (DM2)/coronary heart disease (CHD) patients and is associated with adverse health effects. A promising strategy to reduce burden of disease is to identify patients at risk for depression in order to offer indicated prevention. This study aims to assess the diagnostic accuracy of the Patient Health Questionnaire-9 (PHQ-9) to be used as a tool to identify high risk patients. In this cross-sectional study, 586 consecutive DM2/CHD patients aged >18 were recruited through 23 general practices. PHQ-9 outcomes were compared to the Mini International Neuropsychiatric Interview (MINI), which was considered the reference standard. Diagnostic accuracy was evaluated for minor and major depression, comparing both sum- and algorithm based PHQ-9 scores. For minor depression, the optimal cut-off score was 8 (sensitivity 71%, specificity 71% and an AUC of 0.74). For major depression, the optimal cut-off score was 10 resulting in a sensitivity of 84%, a specificity of 82%, and an AUC of 0.88. The positive predictive value of the PHQ-9 algorithm for diagnosing minor and major depression was 25% and 33%, respectively. Two main limitations apply. MINI Interviewers were not blinded for PHQ-9 scores and less than 10% of all invited patients could be included in the analyses. This could have resulted in biased outcomes. The PHQ-9 sum score performs well in identifying patients at high risk of minor and major depression. However, the PHQ-9 showed suboptimal results for diagnostic purposes. Therefore, it is recommended to combine the use of the PHQ-9 with further diagnostics to identify depression. Copyright © 2015 Elsevier B.V. All rights reserved.

Characterization and classification of lupus patients based on plasma thermograms

PubMed Central

Chaires, Jonathan B.; Mekmaysy, Chongkham S.; DeLeeuw, Lynn; Sivils, Kathy L.; Harley, John B.; Rovin, Brad H.; Kulasekera, K. B.; Jarjour, Wael N.

2017-01-01

Objective Plasma thermograms (thermal stability profiles of blood plasma) are being utilized as a new diagnostic approach for clinical assessment. In this study, we investigated the ability of plasma thermograms to classify systemic lupus erythematosus (SLE) patients versus non SLE controls using a sample of 300 SLE and 300 control subjects from the Lupus Family Registry and Repository. Additionally, we evaluated the heterogeneity of thermograms along age, sex, ethnicity, concurrent health conditions and SLE diagnostic criteria. Methods Thermograms were visualized graphically for important differences between covariates and summarized using various measures. A modified linear discriminant analysis was used to segregate SLE versus control subjects on the basis of the thermograms. Classification accuracy was measured based on multiple training/test splits of the data and compared to classification based on SLE serological markers. Results Median sensitivity, specificity, and overall accuracy based on classification using plasma thermograms was 86%, 83%, and 84% compared to 78%, 95%, and 86% based on a combination of five antibody tests. Combining thermogram and serology information together improved sensitivity from 78% to 86% and overall accuracy from 86% to 89% relative to serology alone. Predictive accuracy of thermograms for distinguishing SLE and osteoarthritis / rheumatoid arthritis patients was comparable. Both gender and anemia significantly interacted with disease status for plasma thermograms (p<0.001), with greater separation between SLE and control thermograms for females relative to males and for patients with anemia relative to patients without anemia. Conclusion Plasma thermograms constitute an additional biomarker which may help improve diagnosis of SLE patients, particularly when coupled with standard diagnostic testing. Differences in thermograms according to patient sex, ethnicity, clinical and environmental factors are important considerations for application of thermograms in a clinical setting. PMID:29149219

Examining Curricular Integration Strategies To Optimize Learning Of The Anatomical Sciences

NASA Astrophysics Data System (ADS)

Lisk, Kristina Adriana Ayako

Background: Integration of basic and clinical science knowledge is essential to clinical practice. Although the importance of these two knowledge domains is well-recognized, successfully supporting the development of learners' integrated basic and clinical science knowledge, remains an educational challenge. In this dissertation, I examine curricular integration strategies to optimize learning of the anatomical sciences. Objectives: The studies were designed to achieve the following research aims: 1) to objectively identify clinically relevant content for an integrated musculoskeletal anatomy curriculum; 2) to examine the value of integrated anatomy and clinical science instruction compared to clinical science instruction alone on novices' diagnostic accuracy and diagnostic reasoning process; 3) to compare the effect of integrating and segregating anatomy and clinical science instruction along with a learning strategy (self-explanation) on novices' diagnostic accuracy. Methods: A modified Delphi was used to objectively select clinically relevant content for an integrated musculoskeletal anatomy curriculum. Two experimental studies were created to compare different instructional strategies to optimize learning of the curricular content. In both of these studies, novice learners were taught the clinical features of musculoskeletal pathologies using different learning approaches. Diagnostic performance was measured immediately after instruction and one-week later. Results: The results show that the Delphi method is an effective strategy to select clinically relevant content for integrated anatomy curricula. The findings also demonstrate that novices who were explicitly taught the clinical features of musculoskeletal diseases using causal basic science descriptions had superior diagnostic accuracy and a better understanding of the relative importance of key clinical features for disease categories. Conclusions: This research demonstrates how integration strategies can be applied at multiple levels of the curriculum. Further, this work shows the value of cognitive integration of anatomy and clinical science and it emphasizes the importance of purposefully linking the anatomical and clinical sciences in day-to-day teaching.

Identification of Nasal Bone Fractures on Conventional Radiography and Facial CT: Comparison of the Diagnostic Accuracy in Different Imaging Modalities and Analysis of Interobserver Reliability

PubMed Central

Baek, Hye Jin; Kim, Dong Wook; Ryu, Ji Hwa; Lee, Yoo Jin

2013-01-01

Background There has been no study to compare the diagnostic accuracy of an experienced radiologist with a trainee in nasal bone fracture. Objectives To compare the diagnostic accuracy between conventional radiography and computed tomography (CT) for the identification of nasal bone fractures and to evaluate the interobserver reliability between a staff radiologist and a trainee. Patients and Methods A total of 108 patients who underwent conventional radiography and CT after acute nasal trauma were included in this retrospective study. Two readers, a staff radiologist and a second-year resident, independently assessed the results of the imaging studies. Results Of the 108 patients, the presence of a nasal bone fracture was confirmed in 88 (81.5%) patients. The number of non-depressed fractures was higher than the number of depressed fractures. In nine (10.2%) patients, nasal bone fractures were only identified on conventional radiography, including three depressed and six non-depressed fractures. CT was more accurate as compared to conventional radiography for the identification of nasal bone fractures as determined by both readers (P <0.05), all diagnostic indices of an experienced radiologist were similar to or higher than those of a trainee, and κ statistics showed moderate agreement between the two diagnostic tools for both readers. There was no statistical difference in the assessment of interobserver reliability for both imaging modalities in the identification of nasal bone fractures. Conclusion For the identification of nasal bone fractures, CT was significantly superior to conventional radiography. Although a staff radiologist showed better values in the identification of nasal bone fracture and differentiation between depressed and non-depressed fractures than a trainee, there was no statistically significant difference in the interpretation of conventional radiography and CT between a radiologist and a trainee. PMID:24348599

Comparison of the diagnostic efficacy between ultrasound elastography and magnetic resonance imaging for breast masses

PubMed Central

Cheng, Rong; Li, Jing; Ji, Li; Liu, Huining; Zhu, Limin

2018-01-01

The present study compared the efficacy of ultrasound elastography (UE), magnetic resonance imaging (MRI) and the combination of the two methods (UE+MRI) in the differential diagnosis of benign and malignant breast tumors. In total, 86 patients with breast masses were recruited and evaluated by UE, MRI and UE+MRI. Strain ratios of UE were calculated for the breast mass and adjacent normal tissues. In addition, the receiver operating characteristic (ROC) curve was obtained, while the sensitivity and specificity were calculated to determine the optimal cut-off point for the differential diagnosis. The area under the ROC curve (AUC) was also calculated to evaluate the diagnostic performance of these methods. The results indicated that the diagnostic accuracy of UE+MRI was significantly higher compared with the UE or MRI methods in the differential diagnosis of invasive ductal, invasive lobular, intraductal papillary, medullary and mucinous carcinomas (all P<0.05). The optimal cut-off points of ROC curve of the Strain Ratio in the diagnosis of breast lesions were 2.81, 3.76 and 3.42 for UE, MRI and UE+MRI, respectively. Furthermore, the AUC values were 86.7, 79.2 and 91.4%, while the diagnostic accuracy rates were 82.5, 75.5 and 95.3%, for UE, MRI and UE+MRI, respectively. Accuracy rate differences between UE and MRI or between UE and UE+MRI were statistically significant (P<0.05), whereas no significant difference existed between MRI and UE+MRI (P>0.05). Finally, the diagnostic consistency of the UE+MRI method with the pathological diagnosis was higher compared with UE or MRI alone. In conclusion, the combination of UE and MRI is superior to the use of UE or MRI alone in the differential diagnosis of benign and malignant breast masses. PMID:29456656

Receiver operating characteristic analysis of eyewitness memory: comparing the diagnostic accuracy of simultaneous versus sequential lineups.

PubMed

Mickes, Laura; Flowe, Heather D; Wixted, John T

2012-12-01

A police lineup presents a real-world signal-detection problem because there are two possible states of the world (the suspect is either innocent or guilty), some degree of information about the true state of the world is available (the eyewitness has some degree of memory for the perpetrator), and a decision is made (identifying the suspect or not). A similar state of affairs applies to diagnostic tests in medicine because, in a patient, the disease is either present or absent, a diagnostic test yields some degree of information about the true state of affairs, and a decision is made about the presence or absence of the disease. In medicine, receiver operating characteristic (ROC) analysis is the standard method for assessing diagnostic accuracy. By contrast, in the eyewitness memory literature, this powerful technique has never been used. Instead, researchers have attempted to assess the diagnostic performance of different lineup procedures using methods that cannot identify the better procedure (e.g., by computing a diagnosticity ratio). Here, we describe the basics of ROC analysis, explaining why it is needed and showing how to use it to measure the performance of different lineup procedures. To illustrate the unique advantages of this technique, we also report 3 ROC experiments that were designed to investigate the diagnostic accuracy of simultaneous versus sequential lineups. According to our findings, the sequential procedure appears to be inferior to the simultaneous procedure in discriminating between the presence versus absence of a guilty suspect in a lineup.

Accuracy of Four Imaging Techniques for Diagnosis of Posterior Pelvic Floor Disorders.

PubMed

van Gruting, Isabelle M A; Stankiewicz, Aleksandra; Kluivers, Kirsten; De Bin, Riccardo; Blake, Helena; Sultan, Abdul H; Thakar, Ranee

2017-11-01

To establish the diagnostic test accuracy of evacuation proctography, magnetic resonance imaging (MRI), transperineal ultrasonography, and endovaginal ultrasonography for detecting posterior pelvic floor disorders (rectocele, enterocele, intussusception, and anismus) in women with obstructed defecation syndrome and secondarily to identify the most patient-friendly imaging technique. In this prospective cohort study, 131 women with symptoms of obstructed defecation syndrome underwent evacuation proctogram, MRI, and transperineal and endovaginal ultrasonography. Images were analyzed by two blinded observers. In the absence of a reference standard, latent class analysis was used to assess diagnostic test accuracy of multiple tests with area under the curve (AUC) as the primary outcome measure. Secondary outcome measures were interobserver agreement calculated as Cohen's κ and patient acceptability using a visual analog scale. No significant differences in diagnostic accuracy were found among the imaging techniques for all the target conditions. Estimates of diagnostic test accuracy were highest for rectocele using MRI (AUC 0.79) or transperineal ultrasonography (AUC 0.85), for enterocele using transperineal (AUC 0.73) or endovaginal ultrasonography (AUC 0.87), for intussusception using evacuation proctography (AUC 0.76) or endovaginal ultrasonography (AUC 0.77), and for anismus using endovaginal (AUC 0.95) or transperineal ultrasonography (AUC 0.78). Interobserver agreement for the diagnosis of rectocele (κ 0.53-0.72), enterocele (κ 0.54-0.94) and anismus (κ 0.43-0.81) was moderate to excellent, but poor to fair for intussusception (κ -0.03 to 0.37) with all techniques. Patient acceptability was better for transperineal and endovaginal ultrasonography as compared with MRI and evacuation proctography (P<.001). Evacuation proctography, MRI, and transperineal and endovaginal ultrasonography were shown to have similar diagnostic test accuracy. Evacuation proctography is not the best available imaging technique. There is no one optimal test for the diagnosis of all posterior pelvic floor disorders. Because transperineal and endovaginal ultrasonography have good test accuracy and patient acceptability, we suggest these could be used for initial assessment of obstructed defecation syndrome. ClinicalTrials.gov, NCT02239302.

Linear combination methods to improve diagnostic/prognostic accuracy on future observations

PubMed Central

Kang, Le; Liu, Aiyi; Tian, Lili

2014-01-01

Multiple diagnostic tests or biomarkers can be combined to improve diagnostic accuracy. The problem of finding the optimal linear combinations of biomarkers to maximise the area under the receiver operating characteristic curve has been extensively addressed in the literature. The purpose of this article is threefold: (1) to provide an extensive review of the existing methods for biomarker combination; (2) to propose a new combination method, namely, the nonparametric stepwise approach; (3) to use leave-one-pair-out cross-validation method, instead of re-substitution method, which is overoptimistic and hence might lead to wrong conclusion, to empirically evaluate and compare the performance of different linear combination methods in yielding the largest area under receiver operating characteristic curve. A data set of Duchenne muscular dystrophy was analysed to illustrate the applications of the discussed combination methods. PMID:23592714

Diagnostic accuracy of tests to detect Hepatitis C antibody: a meta-analysis and review of the literature.

PubMed

Tang, Weiming; Chen, Wen; Amini, Ali; Boeras, Debi; Falconer, Jane; Kelly, Helen; Peeling, Rosanna; Varsaneux, Olivia; Tucker, Joseph D; Easterbrook, Philippa

2017-11-01

Although direct-acting antivirals can achieve sustained virological response rates greater than 90% in Hepatitis C Virus (HCV) infected persons, at present the majority of HCV-infected individuals remain undiagnosed and therefore untreated. While there are a wide range of HCV serological tests available, there is a lack of formal assessment of their diagnostic performance. We undertook a systematic review and meta-analysis to evaluate he diagnostic accuracy of available rapid diagnostic tests (RDT) and laboratory based EIA assays in detecting antibodies to HCV. We used the PRISMA checklist and Cochrane guidance to develop our search protocol. The search strategy was registered in PROSPERO (CRD42015023567). The search focused on hepatitis C, diagnostic tests, and diagnostic accuracy within eight databases (MEDLINE, EMBASE, the Cochrane Central Register of Controlled Trials, Science Citation Index Expanded, Conference Proceedings Citation Index-Science, SCOPUS, Literatura Latino-Americana e do Caribe em Ciências da Saúde and WHO Global Index Medicus. Studies were included if they evaluated an assay to determine the sensitivity and specificity of HCV antibody (HCV Ab) in humans. Two reviewers independently extracted data and performed a quality assessment of the studies using the QUADAS tool. We pooled test estimates using the DerSimonian-Laird method, by using the software R and RevMan. 5.3. A total of 52 studies were identified that included 52,673 unique test measurements. Based on five studies, the pooled sensitivity and specificity of HCV Ab rapid diagnostic tests (RDTs) were 98% (95% CI 98-100%) and 100% (95% CI 100-100%) compared to an enzyme immunoassay (EIA) reference standard. High HCV Ab RDTs sensitivity and specificity were observed across screening populations (general population, high risk populations, and hospital patients) using different reference standards (EIA, nucleic acid testing, immunoblot). There were insufficient studies to undertake subanalyses based on HIV co-infection. Oral HCV Ab RDTs also had excellent sensitivity and specificity compared to blood reference tests, respectively at 94% (95% CI 93-96%) and 100% (95% CI 100-100%). Among studies that assessed individual oral RDTs, the eight studies revealed that OraQuick ADVANCE® had a slightly higher sensitivity (98%, 95% CI 97-98%) compared to the other oral brands (pooled sensitivity: 88%, 95% CI 84-92%). RDTs, including oral tests, have excellent sensitivity and specificity compared to laboratory-based methods for HCV antibody detection across a wide range of settings. Oral HCV Ab RDTs had good sensitivity and specificity compared to blood reference standards.

First-line sonographic diagnosis of pneumothorax in major trauma: accuracy of e-FAST and comparison with multidetector computed tomography.

PubMed

Ianniello, Stefania; Di Giacomo, Vincenza; Sessa, Barbara; Miele, Vittorio

2014-09-01

Combined clinical examination and supine chest radiography have shown low accuracy in the assessment of pneumothorax in unstable patients with major chest trauma during the primary survey in the emergency room. The aim of our study was to evaluate the diagnostic accuracy of extended-focused assessment with sonography in trauma (e-FAST), in the diagnosis of pneumothorax, compared with the results of multidetector computed tomography (MDCT) and of invasive interventions (thoracostomy tube placement). This was a retrospective case series involving 368 consecutive unstable adult patients (273 men and 95 women; average age, 25 years; range, 16-68 years) admitted to our hospital's emergency department between January 2011 and December 2012 for major trauma (Injury Severity Score ≥ 15). We evaluated the accuracy of thoracic ultrasound in the detection of pneumothorax compared with the results of MDCT and invasive interventions (thoracostomy tube placement). Institutional review board approval was obtained prior to commencement of this study. Among the 736 lung fields included in the study, 87 pneumothoraces were detected with thoracic CT scans (23.6%). e-FAST detected 67/87 and missed 20 pneumothoraces (17 mild, 3 moderate). The diagnostic performance of ultrasound was: sensitivity 77% (74% in 2011 and 80% in 2012), specificity 99.8%, positive predictive value 98.5%, negative predictive value 97%, accuracy 97.2% (67 true positive; 668 true negative; 1 false positive; 20 false negative); 17 missed mild pneumothoraces were not immediately life-threatening (thickness less than 5 mm). Thoracic ultrasound (e-FAST) is a rapid and accurate first-line, bedside diagnostic modality for the diagnosis of pneumothorax in unstable patients with major chest trauma during the primary survey in the emergency room.

Application and Utility of iPads in Pediatric Tele-echocardiography.

PubMed

Colombo, Jamie N; Seckeler, Michael D; Barber, Brent J; Krupinski, Elizabeth A; Weinstein, Ronald S; Sisk, David; Lax, Daniela

2016-05-01

Telemedicine is used with increasing frequency to improve patient care in remote areas. The interpretation of medical imaging on iPad(®) (Apple, Cupertino, CA) tablets has been reported to be accurate. There are no studies on the use of iPads for interpretation of pediatric echocardiograms. We compared the quality of echo images, diagnostic accuracy, and review time using three different modalities: remote access on an iPad Air (iPad), remote access via a computer (Remote), and direct access on a computer linked through Ethernet to the server, the "gold standard" (Direct). Fifty consecutive archived pediatric echocardiograms were interpreted using the three modalities. Studies were analyzed blindly by three pediatric cardiologists; review time, diagnostic accuracy, and image quality were documented. Diagnostic accuracy was assessed by comparing the study diagnoses with the official diagnosis in the patient's chart. Discrepancies between diagnoses were graded as major (more than one grade difference) or minor (one grade difference in severity of lesion). There were no significant differences in accuracy among the three modalities. There was one major discrepancy (size of patent ductus arteriosus); all others were minor, hemodynamically insignificant. Image quality ratings were better for iPad than Remote; Direct had the highest ratings. Review times (mean [standard deviation] minutes) were longest for iPad (5.89 [3.87]) and then Remote (4.72 [2.69]), with Direct having the shortest times (3.52 [1.42]) (p < 0.0001). Pediatric echocardiograms can be interpreted using convenient, portable devices while preserving accuracy and quality with slightly longer review times (1-2 min). These findings are important in the current era of increasing need for mobile health.

Diagnostic Accuracy of Central Venous Catheter Confirmation by Bedside Ultrasound Versus Chest Radiography in Critically Ill Patients: A Systematic Review and Meta-Analysis.

PubMed

Ablordeppey, Enyo A; Drewry, Anne M; Beyer, Alexander B; Theodoro, Daniel L; Fowler, Susan A; Fuller, Brian M; Carpenter, Christopher R

2017-04-01

We performed a systematic review and meta-analysis to examine the accuracy of bedside ultrasound for confirmation of central venous catheter position and exclusion of pneumothorax compared with chest radiography. PubMed, Embase, Cochrane Central Register of Controlled Trials, reference lists, conference proceedings and ClinicalTrials.gov. Articles and abstracts describing the diagnostic accuracy of bedside ultrasound compared with chest radiography for confirmation of central venous catheters in sufficient detail to reconstruct 2 × 2 contingency tables were reviewed. Primary outcomes included the accuracy of confirming catheter positioning and detecting a pneumothorax. Secondary outcomes included feasibility, interrater reliability, and efficiency to complete bedside ultrasound confirmation of central venous catheter position. Investigators abstracted study details including research design and sonographic imaging technique to detect catheter malposition and procedure-related pneumothorax. Diagnostic accuracy measures included pooled sensitivity, specificity, positive likelihood ratio, and negative likelihood ratio. Fifteen studies with 1,553 central venous catheter placements were identified with a pooled sensitivity and specificity of catheter malposition by ultrasound of 0.82 (0.77-0.86) and 0.98 (0.97-0.99), respectively. The pooled positive and negative likelihood ratios of catheter malposition by ultrasound were 31.12 (14.72-65.78) and 0.25 (0.13-0.47). The sensitivity and specificity of ultrasound for pneumothorax detection was nearly 100% in the participating studies. Bedside ultrasound reduced mean central venous catheter confirmation time by 58.3 minutes. Risk of bias and clinical heterogeneity in the studies were high. Bedside ultrasound is faster than radiography at identifying pneumothorax after central venous catheter insertion. When a central venous catheter malposition exists, bedside ultrasound will identify four out of every five earlier than chest radiography.

Combining information from 3 anatomic regions in the diagnosis of glaucoma with time-domain optical coherence tomography.

PubMed

Wang, Mingwu; Lu, Ake Tzu-Hui; Varma, Rohit; Schuman, Joel S; Greenfield, David S; Huang, David

2014-03-01

To improve the diagnosis of glaucoma by combining time-domain optical coherence tomography (TD-OCT) measurements of the optic disc, circumpapillary retinal nerve fiber layer (RNFL), and macular retinal thickness. Ninety-six age-matched normal and 96 perimetric glaucoma participants were included in this observational, cross-sectional study. Or-logic, support vector machine, relevance vector machine, and linear discrimination function were used to analyze the performances of combined TD-OCT diagnostic variables. The area under the receiver-operating curve (AROC) was used to evaluate the diagnostic accuracy and to compare the diagnostic performance of single and combined anatomic variables. The best RNFL thickness variables were the inferior (AROC=0.900), overall (AROC=0.892), and superior quadrants (AROC=0.850). The best optic disc variables were horizontal integrated rim width (AROC=0.909), vertical integrated rim area (AROC=0.908), and cup/disc vertical ratio (AROC=0.890). All macular retinal thickness variables had AROCs of 0.829 or less. Combining the top 3 RNFL and optic disc variables in optimizing glaucoma diagnosis, support vector machine had the highest AROC, 0.954, followed by or-logic (AROC=0.946), linear discrimination function (AROC=0.946), and relevance vector machine (AROC=0.943). All combination diagnostic variables had significantly larger AROCs than any single diagnostic variable. There are no significant differences among the combination diagnostic indices. With TD-OCT, RNFL and optic disc variables had better diagnostic accuracy than macular retinal variables. Combining top RNFL and optic disc variables significantly improved diagnostic performance. Clinically, or-logic classification was the most practical analytical tool with sufficient accuracy to diagnose early glaucoma.

Visual and Quantitative Assessment of Coronary Stenoses at Angiography Versus Fractional Flow Reserve: The Impact of Risk Factors.

PubMed

Adjedj, Julien; Xaplanteris, Panagiotis; Toth, Gabor; Ferrara, Angela; Pellicano, Mariano; Ciccarelli, Giovanni; Floré, Vincent; Barbato, Emanuele; De Bruyne, Bernard

2017-07-01

The correlation between angiographic assessment of coronary stenoses and fractional flow reserve (FFR) is weak. Whether and how risk factors impact the diagnostic accuracy of angiography is unknown. We sought to evaluate the diagnostic accuracy of angiography by visual estimate and by quantitative coronary angiography when compared with FFR and evaluate the influence of risk factors (RF) on this accuracy. In 1382 coronary stenoses (1104 patients), percent diameter stenosis by visual estimation (DS VE ) and by quantitative coronary angiography (DS QCA ) was compared with FFR. Patients were divided into 4 subgroups, according to the presence of RFs, and the relationship between DS VE , DS QCA , and FFR was analyzed. Overall, DS VE was significantly higher than DS QCA ( P <0.0001); nonetheless, when examined by strata of DS, DS VE was significantly smaller than DS QCA in mild stenoses, although the reverse held true for severe stenoses. Compared with FFR, a large scatter was observed for both DS VE and DS QCA . When using a dichotomous FFR value of 0.80, C statistic was significantly higher for DS VE than for DS QCA (0.712 versus 0.640, respectively; P <0.001). C statistics for DS VE decreased progressively as RFs accumulated (0.776 for ≤1 RF, 0.750 for 2 RFs, 0.713 for 3 RFs and 0.627 for ≥4 RFs; P =0.0053). In addition, in diabetics, the relationship between FFR and angiographic indices was particularly weak (C statistics: 0.524 for DS VE and 0.511 for DS QCA ). Overall, DS VE has a better diagnostic accuracy than DS QCA to predict the functional significance of coronary stenosis. The predictive accuracy of angiography is moderate in patients with ≤1 RFs, but weakens as RFs accumulate, especially in diabetics. © 2017 American Heart Association, Inc.

Comparing diagnostic accuracy of bedside ultrasound and radiography for bone fracture screening in multiple trauma patients at the ED.

PubMed

Bolandparvaz, Shahram; Moharamzadeh, Payman; Jamali, Kazem; Pouraghaei, Mahboob; Fadaie, Maryam; Sefidbakht, Sepideh; Shahsavari, Kavous

2013-11-01

Long bone fractures are currently diagnosed using radiography, but radiography has some disadvantages (radiation and being time consuming). The present study compared the diagnostic accuracy of bedside ultrasound and radiography in multiple trauma patients at the emergency department (ED). The study assessed 80 injured patients with multiple trauma from February 2011 to July 2012. The patients were older than 18 years and triaged to the cardiopulmonary resuscitation ward of the ED. Bedside ultrasound and radiography were conducted for them. The findings were separately and blindly assessed by 2 radiologists. Sensitivity, specificity, the positive and negative predictive value, and κ coefficient were measured to assess the accuracy and validity of ultrasound as compared with radiography. The sensitivity of ultrasound for diagnosis of limb bone fractures was not high enough and ranged between 55% and 75% depending on the fracture site. The specificity of this diagnostic method had an acceptable range of 62% to 84%. Ultrasound negative prediction value was higher than other indices under study and ranged between 73% and 83%, but its positive prediction value varied between 33.3% and 71%. The κ coefficient for diagnosis of long bone fractures of upper limb (κ = 0.58) and upper limb joints (κ = 0.47) and long bones of lower limb (κ = 0.52) was within the medium range. However, the value for diagnosing fractures of lower limb joints (κ = 0.47) was relatively low. Bedside ultrasound is not a reliable method for diagnosing fractures of upper and lower limb bones compared with radiography. © 2013 Elsevier Inc. All rights reserved.

Systematic Review of the Diagnostic Accuracy and Therapeutic Effectiveness of Sacroiliac Joint Interventions.

PubMed

Simopoulos, Thomas T; Manchikanti, Laxmaiah; Gupta, Sanjeeva; Aydin, Steve M; Kim, Chong Hwan; Solanki, Daneshvari; Nampiaparampil, Devi E; Singh, Vijay; Staats, Peter S; Hirsch, Joshua A

2015-01-01

The sacroiliac joint is well known as a cause of low back and lower extremity pain. Prevalence estimates are 10% to 25% in patients with persistent axial low back pain without disc herniation, discogenic pain, or radiculitis based on multiple diagnostic studies and systematic reviews. However, at present there are no definitive management options for treating sacroiliac joint pain. To evaluate the diagnostic accuracy and therapeutic effectiveness of sacroiliac joint interventions. A systematic review of the diagnostic accuracy and therapeutic effectiveness of sacroiliac joint interventions. The available literature on diagnostic and therapeutic sacroiliac joint interventions was reviewed. The quality assessment criteria utilized were the Quality Appraisal of Reliability Studies (QAREL) checklist for diagnostic accuracy studies, Cochrane review criteria to assess sources of risk of bias, and Interventional Pain Management Techniques-Quality Appraisal of Reliability and Risk of Bias Assessment (IPM-QRB) criteria for randomized therapeutic trials and Interventional Pain Management Techniques-Quality Appraisal of Reliability and Risk of Bias Assessment for Nonrandomized Studies (IPM-QRBNR) for observational therapeutic assessments. The level of evidence was based on a best evidence synthesis with modified grading of qualitative evidence from Level I to Level V. Data sources included relevant literature published from 1966 through March 2015 that were identified through searches of PubMed and EMBASE, manual searches of the bibliographies of known primary and review articles, and all other sources. For the diagnostic accuracy assessment, and for the therapeutic modalities, the primary outcome measure of pain relief and improvement in functional status were utilized. A total of 11 diagnostic accuracy studies and 14 therapeutic studies were included. The evidence for diagnostic accuracy is Level II for dual diagnostic blocks with at least 70% pain relief as the criterion standard and Level III evidence for single diagnostic blocks with at least 75% pain relief as the criterion standard. The evidence for cooled radiofrequency neurotomy in managing sacroiliac joint pain is Level II to III. The evidence for conventional radiofrequency neurotomy, intraarticular steroid injections, and periarticular injections with steroids or botulinum toxin is limited: Level III or IV. The limitations of this systematic review include inconsistencies in diagnostic accuracy studies with a paucity of high quality, replicative, and consistent literature. The limitations for therapeutic interventions include variations in technique, variable diagnostic standards for inclusion criteria, and variable results. The evidence for the accuracy of diagnostic and therapeutic effectiveness of sacroiliac joint interventions varied from Level II to Level IV.

Sensitivity and specificity of the AdenoPlus point-of-care system in detecting adenovirus in conjunctivitis patients at an ophthalmic emergency department: a diagnostic accuracy study.

PubMed

Kam, K Y Ronald; Ong, Hon Shing; Bunce, Catey; Ogunbowale, Lola; Verma, Seema

2015-09-01

To estimate the diagnostic accuracy (sensitivity and specificity) of the AdenoPlus point-of-care adenoviral test compared to PCR in an ophthalmic accident and emergency service. These findings were compared with those of a previous study. This was a prospective diagnostic accuracy study on 121 patients presenting to an emergency eye unit with a clinical picture of acute adenoviral conjunctivitis. AdenoPlus testing was carried out on one eye of each patient and a PCR analysis was also performed on a swab taken from the same eye. AdenoPlus and PCR results were interpreted by masked personnel. Sensitivity and specificity for the AdenoPlus test were calculated using PCR results as the reference standard. 121 patients were enrolled and 109 met the inclusion criteria. 43 patients (39.4%) tested positive for adenovirus by PCR analysis. The sensitivity of the AdenoPlus swab in detecting adenovirus was 39.5% (17/43, 95% CI 26% to 54%) and specificity was 95.5% (63/66, 95% CI 87% to 98%) compared to PCR. The AdenoPlus test has a high specificity for diagnosing adenoviral conjunctivitis, but in this clinical setting, we could not reproduce the high sensitivity that has been previously published. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Diagnosing autoimmune pancreatitis with the Unifying-Autoimmune-Pancreatitis-Criteria.

PubMed

Schneider, Alexander; Michaely, Henrik; Rückert, Felix; Weiss, Christel; Ströbel, Philipp; Belle, Sebastian; Hirth, Michael; Wilhelm, Torsten J; Haas, Stephan L; Jesenofsky, Ralf; Schönberg, Stefan; Marx, Alexander; Singer, Manfred V; Ebert, Matthias P; Pfützer, Roland H; Löhr, J Matthias

We had developed the Unifying-Autoimmune-Pancreatitis-Criteria (U-AIP) to diagnose autoimmune pancreatitis (AiP) within the M-ANNHEIM classification of chronic pancreatitis. In 2011, International-Consensus-Diagnostic-Criteria (ICDC) to diagnose AiP have been published. We had applied the U-AIP long before the ICDC were available. The aims of the study were, first, to describe patients with AiP diagnosed by the U-AIP; second, to compare diagnostic accuracies of the U-AIP and other diagnostic systems; third, to evaluate the clinical applicability of the U-AIP. From 1998 until 2008, we identified patients with AiP using U-AIP, Japanese-, Korean-, Asian-, Mayo-HISORt-, Revised-Mayo-HISORt- and Italian-criteria. We retrospectively verified the diagnosis by ICDC and Revised-Japanese-2011-criteria, compared diagnostic accuracies of all systems and evaluated all criteria in consecutive patients with pancreatitis (2009 until 2010, Pancreas-Outpatient-Clinic-Cohort, n = 84). We retrospectively validated our diagnostic approach in consecutive patients with a pancreatic lesion requiring surgery (Surgical-Cohort, n = 98). Overall, we identified 21 patients with AiP. Unifying-Autoimmune-Pancreatitis-Criteria and ICDC presented the highest diagnostic accuracies (each 98.8%), highest Youden indices (each 0.95238), and highest proportions of diagnosed patients (each n = 20/21, U-AIP/ICDC vs. other diagnostic systems, p < 0.05, McNemar test). In the Pancreas-Outpatient-Clinic-Cohort, seven patients were diagnosed with AiP (n = 6 by U-AIP, n = 1 by Asian-criteria). International-Consensus-Diagnostic-Criteria confirmed the diagnosis in these individuals. Based on partial fulfillment of U-AIP, AiP was initially suspected in 13% (n = 10/77) of remaining patients from the Pancreas-Outpatient-Clinic-Cohort. In the Surgical-cohort, we identified one patient with AiP by U-AIP and ICDC. Unifying-Autoimmune-Pancreatitis-Criteria revealed a satisfactory clinical applicability and offered an additional approach to diagnose AiP. Copyright © 2017 IAP and EPC. Published by Elsevier B.V. All rights reserved.

Validity and Diagnostic Accuracy of Scores from the Autism Diagnostic Observation Schedule-Generic

ERIC Educational Resources Information Center

Reid, Melissa A.

2012-01-01

The purpose of this study was to examine the internal structure, relationships with other variables, and diagnostic accuracy of scores on the Autism Diagnostic Observation Schedule-Generic (ADOS-G; Lord et al., 1999) for the purpose of diagnostic decision-making. Participants were 462 children enrolled in a public school district in the southern…

Diagnostic Accuracy of Molecular Amplification Tests for Human African Trypanosomiasis—Systematic Review

PubMed Central

Boer, Kimberly R.; Dyserinck, Heleen C.; Büscher, Philippe; Schallig, Henk D. H. F.; Leeflang, Mariska M. G.

2012-01-01

Background A range of molecular amplification techniques have been developed for the diagnosis of Human African Trypanosomiasis (HAT); however, careful evaluation of these tests must precede implementation to ensure their high clinical accuracy. Here, we investigated the diagnostic accuracy of molecular amplification tests for HAT, the quality of articles and reasons for variation in accuracy. Methodology Data from studies assessing diagnostic molecular amplification tests were extracted and pooled to calculate accuracy. Articles were included if they reported sensitivity and specificity or data whereby values could be calculated. Study quality was assessed using QUADAS and selected studies were analysed using the bivariate random effects model. Results 16 articles evaluating molecular amplification tests fulfilled the inclusion criteria: PCR (n = 12), NASBA (n = 2), LAMP (n = 1) and a study comparing PCR and NASBA (n = 1). Fourteen articles, including 19 different studies were included in the meta-analysis. Summary sensitivity for PCR on blood was 99.0% (95% CI 92.8 to 99.9) and the specificity was 97.7% (95% CI 93.0 to 99.3). Differences in study design and readout method did not significantly change estimates although use of satellite DNA as a target significantly lowers specificity. Sensitivity and specificity of PCR on CSF for staging varied from 87.6% to 100%, and 55.6% to 82.9% respectively. Conclusion Here, PCR seems to have sufficient accuracy to replace microscopy where facilities allow, although this conclusion is based on multiple reference standards and a patient population that was not always representative. Future studies should, therefore, include patients for which PCR may become the test of choice and consider well designed diagnostic accuracy studies to provide extra evidence on the value of PCR in practice. Another use of PCR for control of disease could be to screen samples collected from rural areas and test in reference laboratories, to spot epidemics quickly and direct resources appropriately. PMID:22253934

Diagnostic accuracy of molecular amplification tests for human African trypanosomiasis--systematic review.

PubMed

Mugasa, Claire M; Adams, Emily R; Boer, Kimberly R; Dyserinck, Heleen C; Büscher, Philippe; Schallig, Henk D H F; Leeflang, Mariska M G

2012-01-01

A range of molecular amplification techniques have been developed for the diagnosis of Human African Trypanosomiasis (HAT); however, careful evaluation of these tests must precede implementation to ensure their high clinical accuracy. Here, we investigated the diagnostic accuracy of molecular amplification tests for HAT, the quality of articles and reasons for variation in accuracy. Data from studies assessing diagnostic molecular amplification tests were extracted and pooled to calculate accuracy. Articles were included if they reported sensitivity and specificity or data whereby values could be calculated. Study quality was assessed using QUADAS and selected studies were analysed using the bivariate random effects model. 16 articles evaluating molecular amplification tests fulfilled the inclusion criteria: PCR (n = 12), NASBA (n = 2), LAMP (n = 1) and a study comparing PCR and NASBA (n = 1). Fourteen articles, including 19 different studies were included in the meta-analysis. Summary sensitivity for PCR on blood was 99.0% (95% CI 92.8 to 99.9) and the specificity was 97.7% (95% CI 93.0 to 99.3). Differences in study design and readout method did not significantly change estimates although use of satellite DNA as a target significantly lowers specificity. Sensitivity and specificity of PCR on CSF for staging varied from 87.6% to 100%, and 55.6% to 82.9% respectively. Here, PCR seems to have sufficient accuracy to replace microscopy where facilities allow, although this conclusion is based on multiple reference standards and a patient population that was not always representative. Future studies should, therefore, include patients for which PCR may become the test of choice and consider well designed diagnostic accuracy studies to provide extra evidence on the value of PCR in practice. Another use of PCR for control of disease could be to screen samples collected from rural areas and test in reference laboratories, to spot epidemics quickly and direct resources appropriately.

Diagnostic accuracy of histopathologic and cytopathologic examination of Aspergillus species.

PubMed

Shah, Akeesha A; Hazen, Kevin C

2013-01-01

To assess the diagnostic accuracy of histopatho-logic and cytopathologic examination (HCE) of Aspergillus species (spp), we performed an 11-year retrospective review to correlate surgical/cytology cases with a diagnosis of Aspergillus spp with their concurrent fungal culture results. Diagnostic accuracy was defined as the percentage of cases with culture-proven Aspergillus spp divided by the number of cases diagnosed as Aspergillus spp on HCE that had growth on fungal culture. Ninety surgical/cytology cases with concurrent fungal culture were reviewed, 58 of which grew a fungal organism. Of these 58 cases, 45 grew an Aspergillus spp, whereas 13 grew an organism other than Aspergillus spp, including both common (Scedosporium, Fusarium, and Paecilomyces spp) and uncommon mimickers (Trichosporon loubieri), resulting in a diagnostic accuracy of 78%. The low diagnostic accuracy indicates that several fungal organisms can morphologically mimic Aspergillus spp and can only be distinguished by fungal culture and DNA sequencing.

Cross-cultural considerations in administering the center for epidemiologic studies depression scale.

PubMed

Lee, Jung Jae; Kim, Ki Woong; Kim, Tae Hui; Park, Joon Hyuk; Lee, Seok Bum; Park, Jin Woo; McQuoid, Douglas R; Steffens, David C

2011-01-01

Cultural biases may affect the individual responses to questionnaires for depression and thus confound the international or multiethnic researches on depression. We compared the diagnostic accuracy of the Center for Epidemiologic Studies Depression Scale (CES-D) for major depressive disorder (MDD) in late life between Korean and US Caucasian elderly. This study included 332 US Caucasian MDD patients, 116 Korean MDD patients, 125 US Caucasian nondepressed subjects and 700 Korean nondepressed subjects. Differential item functioning and factor analyses were conducted to examine the differences in the response patterns to the CES-D between the US Caucasian and Korean elderly. Diagnostic accuracy of the CES-D for MDD was compared using the area under the receiver-operating characteristic curves (AUC). The Korean elderly were more likely to endorse 6 items compared to the US Caucasians, and the US Caucasian elderly were more likely to endorse 5 items compared to the Koreans. The factor solutions from both ethnic groups were not comparable since the congruence coefficient for the second factor was below 0.46 and that for the first factor did not reach 0.90. The AUC of the CES-D for MDD in Koreans (AUC = 0.850, 95% CI = 0.801-0.899) was significantly smaller than that in US Caucasians (AUC = 0.973, 95% CI = 0.960-0.987), and the optimal cutoff score of the CES-D in the Korean elderly (21/22) was 2 times higher than that in the US Caucasian elderly (10/11). Cross-cultural issues may significantly influence the diagnostic accuracy of depression questionnaires and thus should be considered more carefully than before in both clinical and research settings on multiethnic populations. Copyright © 2010 S. Karger AG, Basel.

Convergent Validity, Concurrent Validity, and Diagnostic Accuracy of the interRAI Depression Rating Scale.

PubMed

Penny, Katherine; Barron, Alex; Higgins, Ann-Marie; Gee, Susan; Croucher, Matthew; Cheung, Gary

2016-09-19

Depression Rating Scale (DRS) is one of the clinical outcome measures of the International Resident Assessment Instrument (interRAI) assessment. The primary aim of this study is to investigate the diagnostic accuracy and concurrent validity of the 3-day assessment window version of the DRS. The performance of DRS was compared with a gold standard clinical diagnosis of depression in 92 patients (age ≥65) who had interRAI version 9.1 Home Care assessment completed within 30 days of discharge from psychogeriatric inpatient care or memory clinic assessment. The DRS had poor diagnostic accuracy for depression diagnosis with an area under the curve of 0.68 (95% confidence interval [CI] = 0.57-0.77). The DRS score had a poor to moderate correlation with the Health of the Nation Outcome Scale 65+ depression item score (r s = 0.30, 95% CI = 0.09-0.48, P = .006). This study and the existing literature raise concerns that the DRS is not an adequate measure of depression. © The Author(s) 2016.

Homogeneity tests of clustered diagnostic markers with applications to the BioCycle Study

PubMed Central

Tang, Liansheng Larry; Liu, Aiyi; Schisterman, Enrique F.; Zhou, Xiao-Hua; Liu, Catherine Chun-ling

2014-01-01

Diagnostic trials often require the use of a homogeneity test among several markers. Such a test may be necessary to determine the power both during the design phase and in the initial analysis stage. However, no formal method is available for the power and sample size calculation when the number of markers is greater than two and marker measurements are clustered in subjects. This article presents two procedures for testing the accuracy among clustered diagnostic markers. The first procedure is a test of homogeneity among continuous markers based on a global null hypothesis of the same accuracy. The result under the alternative provides the explicit distribution for the power and sample size calculation. The second procedure is a simultaneous pairwise comparison test based on weighted areas under the receiver operating characteristic curves. This test is particularly useful if a global difference among markers is found by the homogeneity test. We apply our procedures to the BioCycle Study designed to assess and compare the accuracy of hormone and oxidative stress markers in distinguishing women with ovulatory menstrual cycles from those without. PMID:22733707

Diagnostic accuracy of cone-beam computed tomography scans with high- and low-resolution modes for the detection of root perforations.

PubMed

Shokri, Abbas; Eskandarloo, Amir; Norouzi, Marouf; Poorolajal, Jalal; Majidi, Gelareh; Aliyaly, Alireza

2018-03-01

This study compared the diagnostic accuracy of cone-beam computed tomography (CBCT) scans obtained with 2 CBCT systems with high- and low-resolution modes for the detection of root perforations in endodontically treated mandibular molars. The root canals of 72 mandibular molars were cleaned and shaped. Perforations measuring 0.2, 0.3, and 0.4 mm in diameter were created at the furcation area of 48 roots, simulating strip perforations, or on the external surfaces of 48 roots, simulating root perforations. Forty-eight roots remained intact (control group). The roots were filled using gutta-percha (Gapadent, Tianjin, China) and AH26 sealer (Dentsply Maillefer, Ballaigues, Switzerland). The CBCT scans were obtained using the NewTom 3G (QR srl, Verona, Italy) and Cranex 3D (Soredex, Helsinki, Finland) CBCT systems in high- and low-resolution modes, and were evaluated by 2 observers. The chi-square test was used to assess the nominal variables. In strip perforations, the accuracies of low- and high-resolution modes were 75% and 83% for NewTom 3G and 67% and 69% for Cranex 3D. In root perforations, the accuracies of low- and high-resolution modes were 79% and 83% for NewTom 3G and was 56% and 73% for Cranex 3D. The accuracy of the 2 CBCT systems was different for the detection of strip and root perforations. The Cranex 3D had non-significantly higher accuracy than the NewTom 3G. In both scanners, the high-resolution mode yielded significantly higher accuracy than the low-resolution mode. The diagnostic accuracy of CBCT scans was not affected by the perforation diameter.

Evaluating Malaria Prevalence Using Clinical Diagnosis Compared with Microscopy and Rapid Diagnostic Tests in a Tertiary Healthcare Facility in Rivers State, Nigeria.

PubMed

Wogu, M N; Nduka, F O

2018-01-01

The World Health Organization's policy on laboratory test of all suspected malaria cases before treatment has not yielded significant effects in several rural areas of Sub-Saharan Africa due to inadequate diagnostic infrastructure, leading to high morbidity and mortality rates. A cross-sectional randomized study was conducted to evaluate the validity of clinical malaria diagnosis through comparison with microscopy and rapid diagnostic test kits (RDTs) using 1000 consenting outpatients of a tertiary hospital in Nigeria. Physicians conducted clinical diagnosis, and blood samples were collected through venous procedure and analyzed for malaria parasites using Giemsa microscopy and RDT kits. Microscopy was considered the diagnostic "gold standard" and all data obtained were statistically analyzed using Chi-square test with a P value <0.05 considered significant. Malaria prevalence values of 20.1%, 43.1%, and 29.7% were obtained for clinical diagnosis, microscopy, and RDTs, respectively ( P < 0.05). Values of 47.2%, 95.9%, and 77.8% were obtained for sensitivity, specificity, and diagnostic accuracy, respectively, in clinical diagnosis, while RDTs had sensitivity, specificity, and diagnostic accuracy values of 73.7%, 97.3%, and 88.3%, respectively, when compared to microscopy ( P < 0.05). Clinical diagnosed malaria cases should be confirmed with a parasite-based laboratory diagnosis and more qualitative research is needed to explore why clinicians still use clinical diagnosis despite reported cases of its ineffectiveness.

Factors Determining the Inter-observer Variability and Diagnostic Accuracy of High-resolution Manometry for Esophageal Motility Disorders.

PubMed

Kim, Ji Hyun; Kim, Sung Eun; Cho, Yu Kyung; Lim, Chul-Hyun; Park, Moo In; Hwang, Jin Won; Jang, Jae-Sik; Oh, Minkyung

2018-01-30

Although high-resolution manometry (HRM) has the advantage of visual intuitiveness, its diagnostic validity remains under debate. The aim of this study was to evaluate the diagnostic accuracy of HRM for esophageal motility disorders. Six staff members and 8 trainees were recruited for the study. In total, 40 patients enrolled in manometry studies at 3 institutes were selected. Captured images of 10 representative swallows and a single swallow in analyzing mode in both high-resolution pressure topography (HRPT) and conventional line tracing formats were provided with calculated metrics. Assessments of esophageal motility disorders showed fair agreement for HRPT and moderate agreement for conventional line tracing (κ = 0.40 and 0.58, respectively). With the HRPT format, the k value was higher in category A (esophagogastric junction [EGJ] relaxation abnormality) than in categories B (major body peristalsis abnormalities with intact EGJ relaxation) and C (minor body peristalsis abnormalities or normal body peristalsis with intact EGJ relaxation). The overall exact diagnostic accuracy for the HRPT format was 58.8% and rater's position was an independent factor for exact diagnostic accuracy. The diagnostic accuracy for major disorders was 63.4% with the HRPT format. The frequency of major discrepancies was higher for category B disorders than for category A disorders (38.4% vs 15.4%; P < 0.001). The interpreter's experience significantly affected the exact diagnostic accuracy of HRM for esophageal motility disorders. The diagnostic accuracy for major disorders was higher for achalasia than distal esophageal spasm and jackhammer esophagus.

Predictive capabilities of statistical learning methods for lung nodule malignancy classification using diagnostic image features: an investigation using the Lung Image Database Consortium dataset

NASA Astrophysics Data System (ADS)

Hancock, Matthew C.; Magnan, Jerry F.

2017-03-01

To determine the potential usefulness of quantified diagnostic image features as inputs to a CAD system, we investigate the predictive capabilities of statistical learning methods for classifying nodule malignancy, utilizing the Lung Image Database Consortium (LIDC) dataset, and only employ the radiologist-assigned diagnostic feature values for the lung nodules therein, as well as our derived estimates of the diameter and volume of the nodules from the radiologists' annotations. We calculate theoretical upper bounds on the classification accuracy that is achievable by an ideal classifier that only uses the radiologist-assigned feature values, and we obtain an accuracy of 85.74 (+/-1.14)% which is, on average, 4.43% below the theoretical maximum of 90.17%. The corresponding area-under-the-curve (AUC) score is 0.932 (+/-0.012), which increases to 0.949 (+/-0.007) when diameter and volume features are included, along with the accuracy to 88.08 (+/-1.11)%. Our results are comparable to those in the literature that use algorithmically-derived image-based features, which supports our hypothesis that lung nodules can be classified as malignant or benign using only quantified, diagnostic image features, and indicates the competitiveness of this approach. We also analyze how the classification accuracy depends on specific features, and feature subsets, and we rank the features according to their predictive power, statistically demonstrating the top four to be spiculation, lobulation, subtlety, and calcification.

A randomized trial to determine the diagnostic accuracy of conventional vs. jumbo forceps biopsy of gastric epithelial neoplasias before endoscopic submucosal dissection; open-label study.

PubMed

Jeon, Hyo Keun; Ryu, Ho Yoel; Cho, Mee Yon; Kim, Hyun-Soo; Kim, Jae Woo; Park, Hong Jun; Kim, Moon Young; Baik, Soon Koo; Kwon, Sang Ok; Park, Su Yeon; Won, Sung Ho

2014-10-01

Larger biopsy specimens or increasing the number of biopsies may improve the diagnostic accuracy of gastric epithelial neoplasia (GEN). The aims of this study was to compare the diagnostic accuracies between conventional and jumbo forceps biopsy of GEN before endoscopic submucosal dissection (ESD) and to confirm that increasing the number of biopsies is useful for the diagnosis of GEN. The concordance rate between EFB and ESD specimens was not significantly different between the two groups [83.1 % (54/65) in JG vs. 79.1 % (53/67) in CG]. On multivariate analyses, two or four EFBs significantly increased the cumulating concordance rate [coefficients; twice: 5.1 (P = 0.01), four times: 5.9 (P = 0.02)]. But, the concordance rate was decreased in high grade dysplasia (coefficient -40.32, P = 0.006). One hundred and sixty GENs from 148 patients were randomized into two groups and finally 67 GENs in 61 patients and 65 GENs in 63 patients were allocated to the conventional group (CG) or jumbo group (JG), respectively. Four endoscopic forceps biopsy (EFB) specimens were obtained from each lesion with conventional (6.8 mm) forceps or jumbo (8 mm) forceps. The histological concordance rate between 4 EFB specimens and ESD specimens was investigated in the two groups. Before ESD, the diagnostic accuracy of GENs was significantly increased not by the use of jumbo forceps biopsy but by increasing the number of biopsies.

Evaluation of the diagnostic accuracy of four-view radiography and conventional computed tomography analysing sacral and pelvic fractures in dogs.

PubMed

Stieger-Vanegas, S M; Senthirajah, S K J; Nemanic, S; Baltzer, W; Warnock, J; Bobe, G

2015-01-01

The purpose of our study was (1) to determine whether four-view radiography of the pelvis is as reliable and accurate as computed tomography (CT) in diagnosing sacral and pelvic fractures, in addition to coxofemoral and sacroiliac joint subluxation or luxation, and (2) to evaluate the effect of the amount of training in reading diagnostic imaging studies on the accuracy of diagnosing sacral and pelvic fractures in dogs. Sacral and pelvic fractures were created in 11 canine cadavers using a lateral impactor. In all cadavers, frog-legged ventro-dorsal, lateral, right and left ventro-45°-medial to dorsolateral oblique frog leg ("rollover 45-degree view") radiographs and a CT of the pelvis were obtained. Two radiologists, two surgeons and two veterinary students classified fractures using a confidence scale and noted the duration of evaluation for each imaging modality and case. The imaging results were compared to gross dissection. All evaluators required significantly more time to analyse CT images compared to radiographic images. Sacral and pelvic fractures, specifically those of the sacral body, ischiatic table, and the pubic bone, were more accurately diagnosed using CT compared to radiography. Fractures of the acetabulum and iliac body were diagnosed with similar accuracy (at least 86%) using either modality. Computed tomography is a better method for detecting canine sacral and some pelvic fractures compared to radiography. Computed tomography provided an accuracy of close to 100% in persons trained in evaluating CT images.

Education-Adjusted Normality Thresholds for FDG-PET in the Diagnosis of Alzheimer Disease.

PubMed

Mainta, Ismini C; Trombella, Sara; Morbelli, Silvia; Frisoni, Giovanni B; Garibotto, Valentina

2018-06-05

A corollary of the reserve hypothesis is that what is regarded as pathological cortical metabolism in patients might vary according to education. The aim of this study is to assess the incremental diagnostic value of education-adjusted over unadjusted thresholds on the diagnostic accuracy of FDG-PET as a biomarker for Alzheimer disease (AD). We compared cortical metabolism in 90 healthy controls and 181 AD patients from the Alzheimer Disease Neuroimaging Initiative (ADNI) database. The AUC of the ROC curve did not differ significantly between the whole group and the higher-education patients or the lower-education subjects. The threshold of wMetaROI values providing 80% sensitivity was lower in higher-education patients and higher in the lower-education patients, compared to the standard threshold derived over the whole AD collective, without, however, significant changes in sensitivity and specificity. These data show that education, as a proxy of reserve, is not a major confounder in the diagnostic accuracy of FDG-PET in AD and the adoption of education-adjusted thresholds is not required in daily practice. © 2018 S. Karger AG, Basel.

Comparison of saline infusion sonohysterography and hysteroscopy in diagnosis of premenopausal women with abnormal uterine bleeding.

PubMed

Soguktas, Suna; Cogendez, Ebru; Kayatas, Semra Eser; Asoglu, Mehmet Resit; Selcuk, Selcuk; Ertekin, Aktug

2012-03-01

The aim of this study was to compare the diagnostic effectiveness of transvaginal sonography (TVS), saline infusion sonohysterography (SIS), and diagnostic hysteroscopy (HS), with the pathologic specimen as a gold standard diagnostic method, in detecting endometrial pathology in premenopausal women with abnormal uterine bleeding. This prospective cohort study was conducted at Zeynep Kamil Education and Training Hospital, Istanbul, Turkey, and included 89 premenopausal women. All participants were examined first by TVS, further investigated with SIS and HS, and finally dilatation and curettage was performed when needed. The results obtained from these three methods were compared with the pathologic diagnoses. The positive and negative likelihood ratios (LR+ and LR-) of TVS, SIS and HS were calculated by comparison with the final pathological diagnosis. In addition, area under the curve (AUC) values were also calculated. Polypoid lesion was the most common abnormal pathology. LR+ and LR- of TVS, SIS, and HS were 3.13 and 0.15, 9.83 and 0.07, 13.7 and 0.02 respectively in detection of any abnormal pathology, and the AUCs of TVS, SIS, and HS were 0.804, 0.920, and 0.954 respectively. When the three procedures were compared with each other separately, HS had the best diagnostic accuracy, and the diagnostic accuracy of HS and SIS was superior to TVS (p(1)=0.000, p(2)=0.000). For the detection of polypoid lesions, HS was the most accurate diagnostic procedure (AUC=0.947), followed by SIS (AUC=0.894) and TVS (AUC=0.778). HS provides the most accurate diagnosis and allows treatment in the same session in premenopausal women with abnormal uterine bleeding. Published by Elsevier Ireland Ltd.

Diagnostic potential of Raman spectroscopy in Barrett's esophagus

NASA Astrophysics Data System (ADS)

Wong Kee Song, Louis-Michel; Molckovsky, Andrea; Wang, Kenneth K.; Burgart, Lawrence J.; Dolenko, Brion; Somorjai, Rajmund L.; Wilson, Brian C.

2005-04-01

Patients with Barrett's esophagus (BE) undergo periodic endoscopic surveillance with random biopsies in an effort to detect dysplastic or early cancerous lesions. Surveillance may be enhanced by near-infrared Raman spectroscopy (NIRS), which has the potential to identify endoscopically-occult dysplastic lesions within the Barrett's segment and allow for targeted biopsies. The aim of this study was to assess the diagnostic performance of NIRS for identifying dysplastic lesions in BE in vivo. Raman spectra (Pexc=70 mW; t=5 s) were collected from Barrett's mucosa at endoscopy using a custom-built NIRS system (λexc=785 nm) equipped with a filtered fiber-optic probe. Each probed site was biopsied for matching histological diagnosis as assessed by an expert pathologist. Diagnostic algorithms were developed using genetic algorithm-based feature selection and linear discriminant analysis, and classification was performed on all spectra with a bootstrap-based cross-validation scheme. The analysis comprised 192 samples (112 non-dysplastic, 54 low-grade dysplasia and 26 high-grade dysplasia/early adenocarcinoma) from 65 patients. Compared with histology, NIRS differentiated dysplastic from non-dysplastic Barrett's samples with 86% sensitivity, 88% specificity and 87% accuracy. NIRS identified 'high-risk' lesions (high-grade dysplasia/early adenocarcinoma) with 88% sensitivity, 89% specificity and 89% accuracy. In the present study, NIRS classified Barrett's epithelia with high and clinically-useful diagnostic accuracy.

Diagnostic rules and algorithms for the diagnosis of non-acute heart failure in patients 80 years of age and older: a diagnostic accuracy and validation study.

PubMed

Smeets, Miek; Degryse, Jan; Janssens, Stefan; Matheï, Catharina; Wallemacq, Pierre; Vanoverschelde, Jean-Louis; Aertgeerts, Bert; Vaes, Bert

2016-10-06

Different diagnostic algorithms for non-acute heart failure (HF) exist. Our aim was to compare the ability of these algorithms to identify HF in symptomatic patients aged 80 years and older and identify those patients at highest risk for mortality. Diagnostic accuracy and validation study. General practice, Belgium. 365 patients with HF symptoms aged 80 years and older (BELFRAIL cohort). Participants underwent a full clinical assessment, including a detailed echocardiographic examination at home. The diagnostic accuracy of 4 different algorithms was compared using an intention-to-diagnose analysis. The European Society of Cardiology (ESC) definition of HF was used as the reference standard for HF diagnosis. Kaplan-Meier curves for 5-year all-cause mortality were plotted and HRs and corresponding 95% CIs were calculated to compare the mortality risk predicting abilities of the different algorithms. Net reclassification improvement (NRI) was calculated. The prevalence of HF was 20% (n=74). The 2012 ESC algorithm yielded the highest sensitivity (92%, 95% CI 83% to 97%) as well as the highest referral rate (71%, n=259), whereas the Oudejans algorithm yielded the highest specificity (73%, 95% CI 68% to 78%) and the lowest referral rate (36%, n=133). These differences could be ascribed to differences in N-terminal probrain natriuretic peptide cut-off values (125 vs 400 pg/mL). The Kelder and Oudejans algorithms exhibited NRIs of 12% (95% CI 0.7% to 22%, p=0.04) and 22% (95% CI 9% to 32%, p<0.001), respectively, compared with the ESC algorithm. All algorithms detected patients at high risk for mortality (HR 1.9, 95% CI 1.4 to 2.5; Kelder) to 2.3 (95% CI 1.7 to 3.1; Oudejans). No significant differences were observed among the algorithms with respect to mortality risk predicting abilities. Choosing a diagnostic algorithm for non-acute HF in elderly patients represents a trade-off between sensitivity and specificity, mainly depending on differences between cut-off values for natriuretic peptides. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

Evaluation of diagnostic value of AgNOR and PAP in early detection of dysplastic changes in leukoplakia and lichen planus - a preliminary case-control study.

PubMed

Rao, Dhanya S; Ali, I M; Annigeri, Rajeshwari G

2017-01-01

Early detection of oral cancer has been the most effective approach to reduce morbidity and mortality of cancer patients. If a lesion is clinically considered suspicious, an easily practicable, non-invasive, painless, safe, and accurate screening method for detection of the dysplastic changes is necessary. In an attempt to procure this, a study was conducted with the aim of determining the diagnostic accuracy of rapid Papanicolaou stain (PAP) and silver-stained nucleolar organizer regions (AgNOR) in brush biopsies of potentially malignant lesions for early detection of oral cancer. Brush biopsies taken from 25 cases of leukoplakia and lichen planus each were stained with rapid PAP and silver nitrate stains. Histopathological correlation was performed and further compared with rapid PAP and AgNOR for its diagnostic validity. Statistically significant increase in the mean AgNOR count was seen from normal epithelium to lichen planus to that of leukoplakia. When compared with rapid PAP, a linear correlation was seen in AgNOR counts and stages of dysplasia in leukoplakia which was also found to be statistically significant. Diagnostic accuracy for AgNOR in leukoplakia was found to be 84%, lichen planus 73%, whereas RAPID PAP showed 72% accuracy. AgNOR analysis may be useful as a quantitative marker of incipient cellular alterations and hence would be helpful in assessing suspicious lesions and thus can be regarded as a valuable adjunct. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Diagnostic accuracy of Xpert MTB/RIF for tuberculosis detection in different regions with different endemic burden: A systematic review and meta-analysis.

PubMed

Li, Shiying; Liu, Bin; Peng, Mingli; Chen, Min; Yin, Wenwei; Tang, Hui; Luo, Yuxuan; Hu, Peng; Ren, Hong

2017-01-01

To estimate the diagnostic accuracy of Xpert MTB/RIF, a systematic review and meta-analysis were carried out. Up to June 20, 2015, multiple databases were screened for relevant studies. Accordingly, 106 studies included 52,410 samples were selected. Diagnostic accuracy of Xpert MTB/RIF for TB detection was validated against either culture or a composite reference standard (CRS). Additionally, selected studies were further subgrouped in four groups based on sample's type, subject's age, status of HIV co-infection and smear-positivity. The overall pooled sensitivity and specificity of Xpert MTB/RIF was 0.85 (95% confidence interval [CI] 0.82-0.88) and 0.98 (95% CI 0.96-0.98), respectively, compared to culture; while it was 0.59 (95% CI 0.44-0.72) and 0.99 (95% CI 0.97-1.00) compared to CRS. The overall sensitivity was lower in countries with high TB prevalence than countries with middle/low prevalence (0.84, 95% CI: 0.80-0.88 versus 0.89, 95% CI: 0.84-0.93). Furthermore, Xpert MTB/RIF has higher sensitivity in patients with positive smears (0.99, 95% CI 0.97-0.99), in patients with pulmonary TB samples (0.87, 95% CI 0.83-0.90), in adults (0.82, 95% CI 0.76-0.86) and in HIV-positive patients (0.81, 95% CI 0.73-0.87). Taken together, Xpert MTB/RIF is a quick and accurate diagnostic assay for TB which will significantly help the physicians to make their clinical decisions.

Visual representation of statistical information improves diagnostic inferences in doctors and their patients.

PubMed

Garcia-Retamero, Rocio; Hoffrage, Ulrich

2013-04-01

Doctors and patients have difficulty inferring the predictive value of a medical test from information about the prevalence of a disease and the sensitivity and false-positive rate of the test. Previous research has established that communicating such information in a format the human mind is adapted to-namely natural frequencies-as compared to probabilities, boosts accuracy of diagnostic inferences. In a study, we investigated to what extent these inferences can be improved-beyond the effect of natural frequencies-by providing visual aids. Participants were 81 doctors and 81 patients who made diagnostic inferences about three medical tests on the basis of information about prevalence of a disease, and the sensitivity and false-positive rate of the tests. Half of the participants received the information in natural frequencies, while the other half received the information in probabilities. Half of the participants only received numerical information, while the other half additionally received a visual aid representing the numerical information. In addition, participants completed a numeracy scale. Our study showed three important findings: (1) doctors and patients made more accurate inferences when information was communicated in natural frequencies as compared to probabilities; (2) visual aids boosted accuracy even when the information was provided in natural frequencies; and (3) doctors were more accurate in their diagnostic inferences than patients, though differences in accuracy disappeared when differences in numerical skills were controlled for. Our findings have important implications for medical practice as they suggest suitable ways to communicate quantitative medical data. Copyright © 2013 Elsevier Ltd. All rights reserved.

MD-miniRNA could be a more accurate biomarker for prostate cancer screening compared with serum prostate-specific antigen level.

PubMed

Xue, Dong; Zhou, Cui-Xing; Shi, Yun-Bo; Lu, Hao; He, Xiao-Zhou

2015-05-01

Prostate cancer and prostatic hyperplasia detection remains a great challenge, lacking of effective non-invasive and specific diagnostic biomarkers. In the current study, we aimed to identify the relative expression of plasma MD-miniRNA and its diagnostic performance in differentiating prostate cancer and prostatic hyperplasia patients from healthy controls, compared with serum prostate-specific antigen (PSA) level. All of the clinical participants (63 prostate cancer patients, 32 prostatic hyperplasia patients, and 50 healthy controls) were obtained from the Third Affiliated Hospital of Suzhou University in China between January 2013 and April 2014. Clinical characteristics were well matched. Plasma samples were extracted to test the relative expression of MD-miniRNA using the method of qRT-PCR. SPSS 22.0 statistical software package was used to analyze the data and GraphPad Prism 6.0 was used to generate the graphs. Relativity expression of plasma MD-miniRNA was significantly upregulated in prostate cancer, compared with prostatic hyperplasia patients and healthy controls. Serum PSA level revealed similar differences among these groups. MD-miniRNA presented a relatively high diagnostic accuracy with AUC of 0.86 (95 % CI 0.80-0.93) in differentiating prostate cancer patients from healthy controls. Simultaneously, MD-miniRNA was able to discriminate prostate cancer patients from prostatic hyperplasia controls with AUC of 0.79 (95 % CI 0.70-0.88). In addition, MD-miniRNA displayed a better diagnostic performance than PSA level. However, the panel of these two biomarkers revealed the best diagnostic performance, compared with either single biomarker. Results of this study showed that plasma MD-miniRNA could serve as a promising and noninvasive biomarker for diagnosing prostate cancer. Further large-scale studies are needed to confirm its clinical diagnosis accuracy.

Physical examination tests for the diagnosis of femoroacetabular impingement. A systematic review.

PubMed

Pacheco-Carrillo, Aitana; Medina-Porqueres, Ivan

2016-09-01

Numerous clinical tests have been proposed to diagnose FAI, but little is known about their diagnostic accuracy. To summarize and evaluate research on the accuracy of physical examination tests for diagnosis of FAI. A search of the PubMed, SPORTDiscus and CINAHL databases was performed. Studies were considered eligible if they compared the results of physical examination tests to those of a reference standard. Methodological quality and internal validity assessment was performed by two independent reviewers using the Quality Assessment of Diagnostic Accuracy Studies (QUADAS) tool. The systematic search strategy revealed 298 potential articles, five of which articles met the inclusion criteria. After assessment using the QUADAS score, four of the five articles were of high quality. Clinical tests included were Impingement sign, IROP test (Internal Rotation Over Pressure), FABER test (Flexion-Abduction-External Rotation), Stinchfield/RSRL (Resisted Straight Leg Raise) test, Scour test, Maximal squat test, and the Anterior Impingement test. IROP test, impingement sign, and FABER test showed the most sensitive values to identify FAI. The diagnostic accuracy of physical examination tests to assess FAI is limited due to its heterogenecity. There is a strong need for sound research of high methodological quality in this area. Copyright © 2016 Elsevier Ltd. All rights reserved.

Study design requirements for RNA sequencing-based breast cancer diagnostics.

PubMed

Mer, Arvind Singh; Klevebring, Daniel; Grönberg, Henrik; Rantalainen, Mattias

2016-02-01

Sequencing-based molecular characterization of tumors provides information required for individualized cancer treatment. There are well-defined molecular subtypes of breast cancer that provide improved prognostication compared to routine biomarkers. However, molecular subtyping is not yet implemented in routine breast cancer care. Clinical translation is dependent on subtype prediction models providing high sensitivity and specificity. In this study we evaluate sample size and RNA-sequencing read requirements for breast cancer subtyping to facilitate rational design of translational studies. We applied subsampling to ascertain the effect of training sample size and the number of RNA sequencing reads on classification accuracy of molecular subtype and routine biomarker prediction models (unsupervised and supervised). Subtype classification accuracy improved with increasing sample size up to N = 750 (accuracy = 0.93), although with a modest improvement beyond N = 350 (accuracy = 0.92). Prediction of routine biomarkers achieved accuracy of 0.94 (ER) and 0.92 (Her2) at N = 200. Subtype classification improved with RNA-sequencing library size up to 5 million reads. Development of molecular subtyping models for cancer diagnostics requires well-designed studies. Sample size and the number of RNA sequencing reads directly influence accuracy of molecular subtyping. Results in this study provide key information for rational design of translational studies aiming to bring sequencing-based diagnostics to the clinic.

Diagnostic accuracy of integrated intravascular ultrasound and optical coherence tomography (IVUS-OCT) system for coronary plaque characterization

NASA Astrophysics Data System (ADS)

Li, Jiawen; Ma, Teng; Mohar, Dilbahar; Correa, Adrian; Minami, Hataka; Jing, Joseph; Zhou, Qifa; Patel, Pranav M.; Chen, Zhongping

2014-03-01

Intravascular ultrasound (IVUS) imaging and optical coherence tomography (OCT), two commonly used intracoronary imaging modalities, play important roles in plaque evaluation. The combined use of IVUS (to visualize the entire plaque volume) and OCT (to quantify the thickness of the plaque cap, if any) is hypothesized to increase plaque diagnostic accuracy. Our group has developed a fully-integrated dual-modality IVUS-OCT imaging system and 3.6F catheter for simultaneous IVUS-OCT imaging with a high resolution and deep penetration depth. However, the diagnostic accuracy of an integrated IVUS-OCT system has not been investigated. In this study, we imaged 175 coronary artery sites (241 regions of interest) from 20 cadavers using our previous reported integrated IVUS-OCT system. IVUS-OCT images were read by two skilled interventional cardiologists. Each region of interest was classified as either calcification, lipid pool or fibrosis. Comparing the diagnosis by cardiologists using IVUSOCT images with the diagnosis by the pathologist, we calculated the sensitivity and specificity for characterization of calcification, lipid pool or fibrosis with this integrated system. In vitro imaging of cadaver coronary specimens demonstrated the complementary nature of these two modalities for plaques classification. A higher accuracy was shown than using a single modality alone.

Amplitude Integrated Electroencephalography Compared With Conventional Video EEG for Neonatal Seizure Detection: A Diagnostic Accuracy Study.

PubMed

Rakshasbhuvankar, Abhijeet; Rao, Shripada; Palumbo, Linda; Ghosh, Soumya; Nagarajan, Lakshmi

2017-08-01

This diagnostic accuracy study compared the accuracy of seizure detection by amplitude-integrated electroencephalography with the criterion standard conventional video EEG in term and near-term infants at risk of seizures. Simultaneous recording of amplitude-integrated EEG (2-channel amplitude-integrated EEG with raw trace) and video EEG was done for 24 hours for each infant. Amplitude-integrated EEG was interpreted by a neonatologist; video EEG was interpreted by a neurologist independently. Thirty-five infants were included in the analysis. In the 7 infants with seizures on video EEG, there were 169 seizure episodes on video EEG, of which only 57 were identified by amplitude-integrated EEG. Amplitude-integrated EEG had a sensitivity of 33.7% for individual seizure detection. Amplitude-integrated EEG had an 86% sensitivity for detection of babies with seizures; however, it was nonspecific, in that 50% of infants with seizures detected by amplitude-integrated EEG did not have true seizures by video EEG. In conclusion, our study suggests that amplitude-integrated EEG is a poor screening tool for neonatal seizures.

Quantitative optical diagnostics in pathology recognition and monitoring of tissue reaction to PDT

NASA Astrophysics Data System (ADS)

Kirillin, Mikhail; Shakhova, Maria; Meller, Alina; Sapunov, Dmitry; Agrba, Pavel; Khilov, Alexander; Pasukhin, Mikhail; Kondratieva, Olga; Chikalova, Ksenia; Motovilova, Tatiana; Sergeeva, Ekaterina; Turchin, Ilya; Shakhova, Natalia

2017-07-01

Optical coherence tomography (OCT) is currently actively introduced into clinical practice. Besides diagnostics, it can be efficiently employed for treatment monitoring allowing for timely correction of the treatment procedure. In monitoring of photodynamic therapy (PDT) traditionally employed fluorescence imaging (FI) can benefit from complementary use of OCT. Additional diagnostic efficiency can be derived from numerical processing of optical diagnostics data providing more information compared to visual evaluation. In this paper we report on application of OCT together with numerical processing for clinical diagnostic in gynecology and otolaryngology, for monitoring of PDT in otolaryngology and on OCT and FI applications in clinical and aesthetic dermatology. Image numerical processing and quantification provides increase in diagnostic accuracy. Keywords: optical coherence tomography, fluorescence imaging, photod

Transcutaneous bowel sonography for inflammatory bowel disease is sensitive and specific when performed in a nonexpert low-volume North American center.

PubMed

Sey, Michael Sai Lai; Gregor, Jamie; Chande, Nilesh; Ponich, Terry; Bhaduri, Mousumi; Lum, Andrea; Zaleski, Witek; Yan, Brian

2013-08-01

Transcutaneous bowel sonography is a nonionizing imaging modality used in inflammatory bowel disease. Although available in Europe, its uptake in North America has been limited. Since the accuracy of bowel sonography is highly operator dependent, low-volume centers in North America may not achieve the same diagnostic accuracy reported in the European literature. Our objective was to determine the diagnostic accuracy of bowel sonography in a nonexpert low-volume center. All cases of bowel sonography at a single tertiary care center during an 18-month period were reviewed. Bowel sonography was compared with reference standards, including small-bowel follow-through, computed tomography, magnetic resonance imaging, colonoscopy, and surgical findings. A total of 103 cases were included for analysis during the study period. The final diagnoses included Crohn disease (72), ulcerative colitis (8), hemolytic uremic syndrome (1), and normal (22). The sensitivity and specificity of bowel sonography for intestinal wall inflammation were 87.8% and 92.6%, respectively. In the subset of patients who had complications of Crohn disease, the sensitivity and specificity were 50% and 100% for fistulas and 14% and 100% for strictures. One patient had an abscess, which was detected by bowel sonography. Abnormal bowel sonographic findings contributed to the escalation of treatment in 55% of cases. Bowel sonography for inflammatory bowel disease can be performed in low-volume centers and provides diagnostic accuracy for luminal disease comparable with published data, although it is less sensitive for complications of Crohn disease.

Accuracy of clinical diagnosis versus the World Health Organization case definition in the Amoy Garden SARS cohort.

PubMed

Wong, W N; Sek, Antonio C H; Lau, Rick F L; Li, K M; Leung, Joe K S; Tse, M L; Ng, Andy H W; Stenstrom, Robert

2003-11-01

To compare the diagnostic accuracy of emergency department (ED) physicians with the World Health Organization (WHO) case definition in a large community-based SARS (severe acute respiratory syndrome) cohort. This was a cohort study of all patients from Hong Kong's Amoy Garden complex who presented to an ED SARS screening clinic during a 2-month outbreak. Clinical findings and WHO case definition criteria were recorded, along with ED diagnoses. Final diagnoses were established independently based on relevant diagnostic tests performed after the ED visit. Emergency physician diagnostic accuracy was compared with that of the WHO SARS case definition. Sensitivity, specificity, predictive values and likelihood ratios were calculated using standard formulae. During the study period, 818 patients presented with SARS-like symptoms, including 205 confirmed SARS, 35 undetermined SARS and 578 non-SARS. Sensitivity, specificity and accuracy were 91%, 96% and 94% for ED clinical diagnosis, versus 42%, 86% and 75% for the WHO case definition. Positive likelihood ratios (LR+) were 21.1 for physician judgement and 3.1 for the WHO criteria. Negative likelihood ratios (LR-) were 0.10 for physician judgement and 0.67 for the WHO criteria, indicating that clinician judgement was a much more powerful predictor than the WHO criteria. Physician clinical judgement was more accurate than the WHO case definition. Reliance on the WHO case definition as a SARS screening tool may lead to an unacceptable rate of misdiagnosis. The SARS case definition must be revised if it is to be used as a screening tool in emergency departments and primary care settings.

Endoscopic ultrasound cytologic brushing vs endoscopic ultrasound: fine needle aspiration for cytological diagnosis of cystic pancreatic lesions. A multicenter, randomized open-label trial.

PubMed

Lariño-Noia, José; de la Iglesia, Daniel; Iglesias-García, Julio; Macías, Manuel; López Martín, Aurelio; Legaz, María Luisa; Vila, Juan; Reyes, Antonio; Abdulkader, Ihab; Domínguez-Muñoz, J Enrique

2018-04-24

the incidence of cystic pancreatic lesions (CPL) in the asymptomatic population is increasing. Achieving a preoperative diagnosis of CPL still remains a challenge. to evaluate the diagnostic accuracy of the cytological diagnosis of CPL from samples obtained by cytology brush versus standard endoscopic ultrasound fine needle aspiration (EUS-FNA). a multicenter, randomized, open-label trial was performed of EUS-cytology brush (EUS-EB) versus EUS-FNA for the cytological diagnosis of CPL. Patients that underwent EUS-FNA with a CPL > 15 mm were included and randomized into two groups: group I, EUS-EB; group II, EUS-FNA. The final diagnosis was based on the histological evaluation of surgical specimens and clinical parameters, imaging and a five year follow-up in non-operated patients. The main outcome was the diagnostic accuracy of both methods. Secondary outcomes were the diagnostic adequacy of specimens and the rate of adverse events. Data were compared using the Chi-squared test. An intention to treat (ITT) and per-protocol (PP) analysis were performed. sixty-five patients were included in the study, 31 in group I and 34 in group II. Three patients initially randomized to group I were changed to group II as it was impossible to obtain a sample using the brush. The mean size of the CPL was 28.2 mm (range 16-60 mm). The diagnostic accuracy of EUS-EB was not superior to EUS-FNA, neither in the ITT nor the PP analysis (44.8% vs 41.1%, p = 0.77 and 38.4% vs 45.9%, p = 0.55). EUS-EB does not improve the diagnostic accuracy of CPL in comparison with EUS-FNA.

Contextual factors and clinical reasoning: differences in diagnostic and therapeutic reasoning in board certified versus resident physicians.

PubMed

McBee, Elexis; Ratcliffe, Temple; Picho, Katherine; Schuwirth, Lambert; Artino, Anthony R; Yepes-Rios, Ana Monica; Masel, Jennifer; van der Vleuten, Cees; Durning, Steven J

2017-11-15

The impact of context on the complex process of clinical reasoning is not well understood. Using situated cognition as the theoretical framework and videos to provide the same contextual "stimulus" to all participants, we examined the relationship between specific contextual factors on diagnostic and therapeutic reasoning accuracy in board certified internists versus resident physicians. Each participant viewed three videotaped clinical encounters portraying common diagnoses in internal medicine. We explicitly modified the context to assess its impact on performance (patient and physician contextual factors). Patient contextual factors, including English as a second language and emotional volatility, were portrayed in the videos. Physician participant contextual factors were self-rated sleepiness and burnout.. The accuracy of diagnostic and therapeutic reasoning was compared with covariates using Fisher Exact, Mann-Whitney U tests and Spearman Rho's correlations as appropriate. Fifteen board certified internists and 10 resident physicians participated from 2013 to 2014. Accuracy of diagnostic and therapeutic reasoning did not differ between groups despite residents reporting significantly higher rates of sleepiness (mean rank 20.45 vs 8.03, U = 0.5, p < .001) and burnout (mean rank 20.50 vs 8.00, U = 0.0, p < .001). Accuracy of diagnosis and treatment were uncorrelated (r = 0.17, p = .65). In both groups, the proportion scoring correct responses for treatment was higher than the proportion scoring correct responses for diagnosis. This study underscores that specific contextual factors appear to impact clinical reasoning performance. Further, the processes of diagnostic and therapeutic reasoning, although related, may not be interchangeable. This raises important questions about the impact that contextual factors have on clinical reasoning and provides insight into how clinical reasoning processes in more authentic settings may be explained by situated cognition theory.

The diagnostic accuracy of multi-frequency bioelectrical impedance analysis in diagnosing dehydration after stroke

PubMed Central

Kafri, Mohannad W.; Myint, Phyo Kyaw; Doherty, Danielle; Wilson, Alexander Hugh; Potter, John F.; Hooper, Lee

2013-01-01

Background Non-invasive methods for detecting water-loss dehydration following acute stroke would be clinically useful. We evaluated the diagnostic accuracy of multi-frequency bioelectrical impedance analysis (MF-BIA) against reference standards serum osmolality and osmolarity. Material/Methods Patients admitted to an acute stroke unit were recruited. Blood samples for electrolytes and osmolality were taken within 20 minutes of MF-BIA. Total body water (TBW%), intracellular (ICW%) and extracellular water (ECW%), as percentages of total body weight, were calculated by MF-BIA equipment and from impedance measures using published equations for older people. These were compared to hydration status (based on serum osmolality and calculated osmolarity). The most promising Receiver Operating Characteristics curves were plotted. Results 27 stroke patients were recruited (mean age 71.3, SD10.7). Only a TBW% cut-off at 46% was consistent with current dehydration (serum osmolality >300 mOsm/kg) and TBW% at 47% impending dehydration (calculated osmolarity ≥295–300 mOsm/L) with sensitivity and specificity both >60%. Even here diagnostic accuracy of MF-BIA was poor, a third of those with dehydration were wrongly classified as hydrated and a third classified as dehydrated were well hydrated. Secondary analyses assessing diagnostic accuracy of TBW% for men and women separately, and using TBW as a percentage of lean body mass showed some promise, but did not provide diagnostically accurate measures across the population. Conclusions MF-BIA appears ineffective at diagnosing water-loss dehydration after stroke and cannot be recommended as a test for dehydration, but separating assessment by sex, and using TBW as a percentage of lean body weight may warrant further investigation. PMID:23839255

Five common tumor biomarkers and CEA for diagnosing early gastric cancer: A protocol for a network meta-analysis of diagnostic test accuracy.

PubMed

Shen, Minghui; Wang, Hui; Wei, Kongyuan; Zhang, Jianling; You, Chongge

2018-05-01

Although surgical resection is the recommended treatment for the patients with gastric cancer, lots of patients show advanced or metastatic gastric cancer at the time of diagnosis. Detection of gastric cancer at early stages is a huge challenge because of lack of appropriate detection tests. Unfortunately, existing clinical guidelines focusing on early diagnosis of gastric cancer do not provide consistent and prudent evidence. Serum carcinoembryonic antigen was considered as a complementary test, although it is not good enough to diagnose early gastric cancer. There are no other tumor markers recommended for diagnosing early gastric cancer. This study aims to evaluate and compare the diagnostic accuracy of 5 common tumor biomarkers (CA19-9, CA125, PG, IncRNA, and DNA methylation) and CEA and their combinations for diagnosing gastric cancer through network meta-analysis method, and to rank these tests using a superiority index. PubMed, EMBASE.com, and the Cochrane Central Register of Controlled Trials (CENTRAL) will be searched from their inception to March 2018. We will include diagnostic tests which assessed the accuracy of the above-mentioned tumor biomarkers and CEA for diagnosing gastric cancer. The risk of bias for each study will be independently assessed as low, moderate, or high using criteria adapted from Quality Assessment of Diagnostic Accuracy Studies 2 (QUADAS-2). Network meta-analysis will be performed using STATA 12.0 and R 3.4.1 software. The competing diagnostic tests will be ranked by a superiority index. This study is ongoing and will be submitted to a peer-reviewed journal for publication. This study will provide systematically suggestions to select different tumor biomarkers for detecting the early gastric cancer.

Accurate ECG diagnosis of atrial tachyarrhythmias using quantitative analysis: a prospective diagnostic and cost-effectiveness study.

PubMed

Krummen, David E; Patel, Mitul; Nguyen, Hong; Ho, Gordon; Kazi, Dhruv S; Clopton, Paul; Holland, Marian C; Greenberg, Scott L; Feld, Gregory K; Faddis, Mitchell N; Narayan, Sanjiv M

2010-11-01

Quantitative ECG Analysis. Optimal atrial tachyarrhythmia management is facilitated by accurate electrocardiogram interpretation, yet typical atrial flutter (AFl) may present without sawtooth F-waves or RR regularity, and atrial fibrillation (AF) may be difficult to separate from atypical AFl or rapid focal atrial tachycardia (AT). We analyzed whether improved diagnostic accuracy using a validated analysis tool significantly impacts costs and patient care. We performed a prospective, blinded, multicenter study using a novel quantitative computerized algorithm to identify atrial tachyarrhythmia mechanism from the surface ECG in patients referred for electrophysiology study (EPS). In 122 consecutive patients (age 60 ± 12 years) referred for EPS, 91 sustained atrial tachyarrhythmias were studied. ECGs were also interpreted by 9 physicians from 3 specialties for comparison and to allow healthcare system modeling. Diagnostic accuracy was compared to the diagnosis at EPS. A Markov model was used to estimate the impact of improved arrhythmia diagnosis. We found 13% of typical AFl ECGs had neither sawtooth flutter waves nor RR regularity, and were misdiagnosed by the majority of clinicians (0/6 correctly diagnosed by consensus visual interpretation) but correctly by quantitative analysis in 83% (5/6, P = 0.03). AF diagnosis was also improved through use of the algorithm (92%) versus visual interpretation (primary care: 76%, P < 0.01). Economically, we found that these improvements in diagnostic accuracy resulted in an average cost-savings of $1,303 and 0.007 quality-adjusted-life-years per patient. Typical AFl and AF are frequently misdiagnosed using visual criteria. Quantitative analysis improves diagnostic accuracy and results in improved healthcare costs and patient outcomes. © 2010 Wiley Periodicals, Inc.

Reliability and diagnostic accuracy of history and physical examination for diagnosing glenoid labral tears.

PubMed

Walsworth, Matthew K; Doukas, William C; Murphy, Kevin P; Mielcarek, Billie J; Michener, Lori A

2008-01-01

Glenoid labral tears provide a diagnostic challenge. Combinations of items in the patient history and physical examination will provide stronger diagnostic accuracy to suggest the presence or absence of glenoid labral tear than will individual items. Cohort study (diagnosis); Level of evidence, 1. History and examination findings in patients with shoulder pain (N = 55) were compared with arthroscopic findings to determine diagnostic accuracy and intertester reliability. The intertester reliability of the crank, anterior slide, and active compression tests was 0.20 to 0.24. A combined history of popping or catching and positive crank or anterior slide results yielded specificities of 0.91 and 1.00 and positive likelihood ratios of 3.0 and infinity, respectively. A positive anterior slide result combined with either a positive active compression or crank result yielded specificities of 0.91 and positive likelihood ratio of 2.75 and 3.75, respectively. Requiring only a single positive finding in the combination of popping or catching and the anterior slide or crank yielded sensitivities of 0.82 and 0.89 and negative likelihood ratios of 0.31 and 0.33, respectively. The diagnostic accuracy of individual tests in previous studies is quite variable, which may be explained in part by the modest reliability of these tests. The combination of popping or catching with a positive crank or anterior slide result or a positive anterior slide result with a positive active compression or crank test result suggests the presence of a labral tear. The combined absence of popping or catching and a negative anterior slide or crank result suggests the absence of a labral tear.

The diagnostic value of a new fecal marker, matrix metalloprotease-9, in different types of inflammatory bowel diseases.

PubMed

Farkas, Klaudia; Saródi, Zoltán; Bálint, Anita; Földesi, Imre; Tiszlavicz, László; Szűcs, Mónika; Nyári, Tibor; Tajti, János; Nagy, Ferenc; Szepes, Zoltán; Bor, Renáta; Annaházi, Anita; Róka, Richárd; Molnár, Tamás

2015-03-01

Only limited data are available regarding the diagnostic accuracy of fecal matrix metalloprotease-9 [MMP-9] for inflammatory bowel disease [IBD]. The aims of our study were to assess the diagnostic accuracy of fecal MMP-9 in patients with active Crohn's disease [CD], ulcerative colitis [UC], and pouchitis, and to compare the diagnostic accuracy of fecal MMP-9 and fecal calprotectin [CP] in IBD. Stool and blood samples were collected in 50 CD, 54 UC, and 34 ileal pouch-anal anastomosis patients before control endoscopies were performed. Biopsies were taken for histologic purposes. The activities of CD, UC, and pouchitis were defined with the use of clinical, endoscopic, and histologic activity scores. Fecal CP and MMP-9 levels were quantified by enzyme-linked immunosorbent assay. Active CD, UC, and pouchitis were detected in 38%, 54%, and 29% of the patients, respectively. A significant correlation was revealed between fecal CP and the clinical activities of CD and UC, and between fecal CP and the endoscopic activity of UC and pouchitis. Fecal MMP-9 did not correlate with any of the activity indices of CD; however, strong associations were shown between fecal MMP-9 and clinical, endoscopic, and histologic activities of both UC and pouchitis. This is the first study assessing the diagnostic accuracy of MMP-9 in different types of IBD. Our results showed that fecal MMP-9 has high sensitivity in the detection of endoscopically active UC and pouchitis. These non-invasive methods help assess intestinal inflammation. Copyright © 2015 European Crohn’s and Colitis Organisation (ECCO). Published by Oxford University Press. All rights reserved. For permissions, please email: journals.permissions@oup.com.

Comparison of computer systems and ranking criteria for automatic melanoma detection in dermoscopic images.

PubMed

Møllersen, Kajsa; Zortea, Maciel; Schopf, Thomas R; Kirchesch, Herbert; Godtliebsen, Fred

2017-01-01

Melanoma is the deadliest form of skin cancer, and early detection is crucial for patient survival. Computer systems can assist in melanoma detection, but are not widespread in clinical practice. In 2016, an open challenge in classification of dermoscopic images of skin lesions was announced. A training set of 900 images with corresponding class labels and semi-automatic/manual segmentation masks was released for the challenge. An independent test set of 379 images, of which 75 were of melanomas, was used to rank the participants. This article demonstrates the impact of ranking criteria, segmentation method and classifier, and highlights the clinical perspective. We compare five different measures for diagnostic accuracy by analysing the resulting ranking of the computer systems in the challenge. Choice of performance measure had great impact on the ranking. Systems that were ranked among the top three for one measure, dropped to the bottom half when changing performance measure. Nevus Doctor, a computer system previously developed by the authors, was used to participate in the challenge, and investigate the impact of segmentation and classifier. The diagnostic accuracy when using an automatic versus the semi-automatic/manual segmentation is investigated. The unexpected small impact of segmentation method suggests that improvements of the automatic segmentation method w.r.t. resemblance to semi-automatic/manual segmentation will not improve diagnostic accuracy substantially. A small set of similar classification algorithms are used to investigate the impact of classifier on the diagnostic accuracy. The variability in diagnostic accuracy for different classifier algorithms was larger than the variability for segmentation methods, and suggests a focus for future investigations. From a clinical perspective, the misclassification of a melanoma as benign has far greater cost than the misclassification of a benign lesion. For computer systems to have clinical impact, their performance should be ranked by a high-sensitivity measure.

Multicenter Evaluation Of Coronary Dual-Source CT angiography in patients with intermediate Risk of Coronary Artery Stenoses (MEDIC): study design and rationale.

PubMed

Marwan, Mohamed; Hausleiter, Jörg; Abbara, Suhny; Hoffmann, Udo; Becker, Christoph; Ovrehus, Kristian; Ropers, Dieter; Bathina, Ravi; Berman, Dan; Anders, Katharina; Uder, Michael; Meave, Aloha; Alexánderson, Erick; Achenbach, Stephan

2014-01-01

The diagnostic performance of multidetector row CT to detect coronary artery stenosis has been evaluated in numerous single-center studies, with only limited data from large cohorts with low-to-intermediate likelihood of coronary disease and in multicenter trials. The Multicenter Evaluation of Coronary Dual-Source CT Angiography in Patients with Intermediate Risk of Coronary Artery Stenoses (MEDIC) trial determines the accuracy of dual-source CT (DSCT) to identify persons with at least 1 coronary artery stenosis among patients with low-to-intermediate pretest likelihood of disease. The MEDIC trial was designed as a prospective, multicenter, international trial to evaluate the diagnostic performance of DSCT for the detection of coronary artery stenosis compared with invasive coronary angiography. The study includes 8 sites in Germany, India, Mexico, the United States, and Denmark. The study population comprises patients referred for a diagnostic coronary angiogram because of suspected coronary artery disease with an intermediate pretest likelihood as determined by sex, age, and symptoms. All evaluations are performed by blinded core laboratory readers. The primary outcome of the MEDIC trial is the accuracy of DSCT to identify the presence of coronary artery stenoses with a luminal diameter narrowing of 50% or more on a per-vessel basis. Secondary outcome parameters include per-patient and per-segment diagnostic accuracy for 50% stenoses and accuracy to identify stenoses of 70% or more. Furthermore, secondary outcome parameters include the influence of heart rate, Agatston score, body weight, body mass index, image quality, and diagnostic confidence on the accuracy to detect coronary artery stenoses >50% on a per-vessel basis. The results of the MEDIC trial will assess the clinical utility of coronary CT angiography in the evaluation of patients with intermediate pretest likelihood of coronary artery disease. Copyright © 2014 Society of Cardiovascular Computed Tomography. All rights reserved.

Standardized Reporting of Prostate MRI: Comparison of the Prostate Imaging Reporting and Data System (PI-RADS) Version 1 and Version 2

PubMed Central

Tewes, Susanne; Mokov, Nikolaj; Hartung, Dagmar; Schick, Volker; Peters, Inga; Schedl, Peter; Pertschy, Stefanie; Wacker, Frank; Voshage, Götz; Hueper, Katja

2016-01-01

Introduction Objective of our study was to determine the agreement between version 1 (v1) and v2 of the Prostate Imaging Reporting and Data System (PI-RADS) for evaluation of multiparametric prostate MRI (mpMRI) and to compare their diagnostic accuracy, their inter-observer agreement and practicability. Material and Methods mpMRI including T2-weighted imaging, diffusion-weighted imaging (DWI) and dynamic contrast-enhanced imaging (DCE) of 54 consecutive patients, who subsequently underwent MRI-guided in-bore biopsy were re-analyzed according to PI-RADS v1 and v2 by two independent readers. Diagnostic accuracy for detection of prostate cancer (PCa) was assessed using ROC-curve analysis. Agreement between PI-RADS versions and observers was calculated and the time needed for scoring was determined. Results MRI-guided biopsy revealed PCa in 31 patients. Diagnostic accuracy for detection of PCa was equivalent with both PI-RADS versions for reader 1 with sensitivities and specificities of 84%/91% (AUC = 0.91 95%CI[0.8–1]) for PI-RADS v1 and 100%/74% (AUC = 0.92 95% CI[0.8–1]) for PI-RADS v2. Reader 2 achieved similar diagnostic accuracy with sensitivity and specificity of 74%/91% (AUC = 0.88 95%CI[0.8–1]) for PI-RADS v1 and 81%/91% (AUC = 0.91 95%CI[0.8–1]) for PI-RADS v2. Agreement between scores determined with different PI-RADS versions was good (reader 1: κ = 0.62, reader 2: κ = 0.64). Inter-observer agreement was moderate with PI-RADS v2 (κ = 0.56) and fair with v1 (κ = 0.39). The time required for building the PI-RADS score was significantly lower with PI-RADS v2 compared to v1 (24.7±2.3 s vs. 41.9±2.6 s, p<0.001). Conclusion Agreement between PI-RADS versions was high and both versions revealed high diagnostic accuracy for detection of PCa. Due to better inter-observer agreement for malignant lesions and less time demand, the new PI-RADS version could be more practicable for clinical routine. PMID:27657729

Sensitivity, Specificity, Predictive Values, and Accuracy of Three Diagnostic Tests to Predict Inferior Alveolar Nerve Blockade Failure in Symptomatic Irreversible Pulpitis

PubMed Central

Rodríguez-Wong, Laura; Noguera-González, Danny; Esparza-Villalpando, Vicente; Montero-Aguilar, Mauricio

2017-01-01

Introduction The inferior alveolar nerve block (IANB) is the most common anesthetic technique used on mandibular teeth during root canal treatment. Its success in the presence of preoperative inflammation is still controversial. The aim of this study was to evaluate the sensitivity, specificity, predictive values, and accuracy of three diagnostic tests used to predict IANB failure in symptomatic irreversible pulpitis (SIP). Methodology A cross-sectional study was carried out on the mandibular molars of 53 patients with SIP. All patients received a single cartridge of mepivacaine 2% with 1 : 100000 epinephrine using the IANB technique. Three diagnostic clinical tests were performed to detect anesthetic failure. Anesthetic failure was defined as a positive painful response to any of the three tests. Sensitivity, specificity, predictive values, accuracy, and ROC curves were calculated and compared and significant differences were analyzed. Results IANB failure was determined in 71.7% of the patients. The sensitivity scores for the three tests (lip numbness, the cold stimuli test, and responsiveness during endodontic access) were 0.03, 0.35, and 0.55, respectively, and the specificity score was determined as 1 for all of the tests. Clinically, none of the evaluated tests demonstrated a high enough accuracy (0.30, 0.53, and 0.68 for lip numbness, the cold stimuli test, and responsiveness during endodontic access, resp.). A comparison of the areas under the curve in the ROC analyses showed statistically significant differences between the three tests (p < 0.05). Conclusion None of the analyzed tests demonstrated a high enough accuracy to be considered a reliable diagnostic tool for the prediction of anesthetic failure. PMID:28694714

Meta-epidemiologic study showed frequent time trends in summary estimates from meta-analyses of diagnostic accuracy studies.

PubMed

Cohen, Jérémie F; Korevaar, Daniël A; Wang, Junfeng; Leeflang, Mariska M; Bossuyt, Patrick M

2016-09-01

To evaluate changes over time in summary estimates from meta-analyses of diagnostic accuracy studies. We included 48 meta-analyses from 35 MEDLINE-indexed systematic reviews published between September 2011 and January 2012 (743 diagnostic accuracy studies; 344,015 participants). Within each meta-analysis, we ranked studies by publication date. We applied random-effects cumulative meta-analysis to follow how summary estimates of sensitivity and specificity evolved over time. Time trends were assessed by fitting a weighted linear regression model of the summary accuracy estimate against rank of publication. The median of the 48 slopes was -0.02 (-0.08 to 0.03) for sensitivity and -0.01 (-0.03 to 0.03) for specificity. Twelve of 96 (12.5%) time trends in sensitivity or specificity were statistically significant. We found a significant time trend in at least one accuracy measure for 11 of the 48 (23%) meta-analyses. Time trends in summary estimates are relatively frequent in meta-analyses of diagnostic accuracy studies. Results from early meta-analyses of diagnostic accuracy studies should be considered with caution. Copyright © 2016 Elsevier Inc. All rights reserved.

Diagnostic accuracy of high-definition CT coronary angiography in high-risk patients.

PubMed

Iyengar, S S; Morgan-Hughes, G; Ukoumunne, O; Clayton, B; Davies, E J; Nikolaou, V; Hyde, C J; Shore, A C; Roobottom, C A

2016-02-01

To assess the diagnostic accuracy of computed tomography coronary angiography (CTCA) using a combination of high-definition CT (HD-CTCA) and high level of reader experience, with invasive coronary angiography (ICA) as the reference standard, in high-risk patients for the investigation of coronary artery disease (CAD). Three hundred high-risk patients underwent HD-CTCA and ICA. Independent experts evaluated the images for the presence of significant CAD, defined primarily as the presence of moderate (≥ 50%) stenosis and secondarily as the presence of severe (≥ 70%) stenosis in at least one coronary segment, in a blinded fashion. HD-CTCA was compared to ICA as the reference standard. No patients were excluded. Two hundred and six patients (69%) had moderate and 178 (59%) had severe stenosis in at least one vessel at ICA. The sensitivity, specificity, positive predictive value, and negative predictive value were 97.1%, 97.9%, 99% and 93.9% for moderate stenosis, and 98.9%, 93.4%, 95.7% and 98.3%, for severe stenosis, on a per-patient basis. The combination of HD-CTCA and experienced readers applied to a high-risk population, results in high diagnostic accuracy comparable to ICA. Modern generation CT systems in experienced hands might be considered for an expanded role. Copyright © 2015 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.

Diagnostic accuracy of APRI, FIB-4 and Forns for the detection of liver cirrhosis in HIV/HCV-coinfected patients.

PubMed

Merli, Marco; Galli, Laura; Castagna, Antonella; Salpietro, Stefania; Gianotti, Nicola; Messina, Emanuela; Poli, Andrea; Morsica, Giulia; Bagaglio, Sabrina; Cernuschi, Massimo; Bigoloni, Alba; Uberti-Foppa, Caterina; Lazzarin, Adriano; Hasson, Hamid

2016-04-01

We determined the diagnostic accuracy and optimal cut off of three indirect fibrosis biomarkers (APRI, FIB-4, Forns) compared with liver stiffness (LS) for the detection of liver cirrhosis in HIV/HCV-coinfected patients. An observational retrospective study on HIV/HCV-coinfected patients with concomitant LS measurement and APRI, FIB-4 and Forns was performed. The presence of liver cirrhosis was defined as a LS ≥13 KPa. The diagnostic accuracy and optimal cut-off values, compared with LS categorization (<13 vs ≥13 KPa), were determined by receiver operating characteristics (ROC) curves. The study sample included 646 patients. The area-under-the ROC curve (95% confidence interval) for the detection of liver cirrhosis were 0.84 (0.81-0.88), 0.87 (0.84-0.91) and 0.87 (0.84-0.90) for APRI, FIB-4 and Forns, respectively. According to the optimal cut off values for liver cirrhosis (≥0.97 for APRI, ≥2.02 for FIB-4 and ≥7.8 for Forns), 80%, 80% and 82% of subjects were correctly classified by the three indirect fibrosis biomarkers, respectively. Misclassifications were mostly due to false positive cases. The study suggests that indirect fibrosis biomarkers can help clinicians to exclude liver cirrhosis in the management of HIV/HCV co-infected patients, reducing the frequency of more expensive or invasive assessments.

High diagnostic accuracy of histone H4-IgG autoantibodies in systemic lupus erythematosus.

PubMed

Vordenbäumen, Stefan; Böhmer, Paloma; Brinks, Ralph; Fischer-Betz, Rebecca; Richter, Jutta; Bleck, Ellen; Rengers, Petra; Göhler, Heike; Zucht, Hans-Dieter; Budde, Petra; Schulz-Knappe, Peter; Schneider, Matthias

2018-03-01

Diagnosis of SLE relies on the detection of autoantibodies. We aimed to assess the diagnostic potential of histone H4 and H2A variant antibodies in SLE. IgG-autoantibodies to histones H4 (HIST1H4A), H2A type 2-A (HIST2H2AA3) and H2A type 2-C (HIST2H2AC) were measured along with a standard antibody (SA) set including SSA, SSB, Sm, U1-RNP and RPLP2 in a multiplex magnetic microsphere-based assay in 153 SLE patients [85% female, 41 (13.5) years] and 81 healthy controls [77% female, 43.3 (12.4) years]. Receiver operating characteristic analysis was performed to assess diagnostic performance of individual markers. Logistic regression analysis was performed on a random split of samples to determine the additional value of histone antibodies in comparison with SA by likelihood ratio test and determination of diagnostic accuracy in the remaining validation samples. Microsphere-based assay showed good interclass correlation (mean 0.85, range 0.73-0.99) and diagnostic performance in receiver operating characteristic analysis (area under the curve (AUC) range 84.8-93.2) compared with routine assay for SA parameters. HIST1H4A-IgG was the marker with the best individual diagnostic performance for SLE vs healthy (AUC 0.97, sensitivity 95% at 90% specificity). HIST1H4A-IgG was an independent significant predictor for the diagnosis of SLE in multivariate modelling (P < 0.0001), and significantly improved prediction of SLE over SA parameters alone (residual deviance 45.9 vs 97.1, P = 4.3 × 10-11). Diagnostic accuracy in the training and validation samples was 89 and 86% for SA, and 95 and 89% with the addition of HIST1H4A-IgG. HIST1H4A-IgG antibodies improve diagnostic accuracy for SLE vs healthy. © The Author(s) 2017. Published by Oxford University Press on behalf of the British Society for Rheumatology. All rights reserved. [br]For Permissions, please email: journals.permissions@oup.com

Sample size in studies on diagnostic accuracy in ophthalmology: a literature survey.

PubMed

Bochmann, Frank; Johnson, Zoe; Azuara-Blanco, Augusto

2007-07-01

To assess the sample sizes used in studies on diagnostic accuracy in ophthalmology. Design and sources: A survey literature published in 2005. The frequency of reporting calculations of sample sizes and the samples' sizes were extracted from the published literature. A manual search of five leading clinical journals in ophthalmology with the highest impact (Investigative Ophthalmology and Visual Science, Ophthalmology, Archives of Ophthalmology, American Journal of Ophthalmology and British Journal of Ophthalmology) was conducted by two independent investigators. A total of 1698 articles were identified, of which 40 studies were on diagnostic accuracy. One study reported that sample size was calculated before initiating the study. Another study reported consideration of sample size without calculation. The mean (SD) sample size of all diagnostic studies was 172.6 (218.9). The median prevalence of the target condition was 50.5%. Only a few studies consider sample size in their methods. Inadequate sample sizes in diagnostic accuracy studies may result in misleading estimates of test accuracy. An improvement over the current standards on the design and reporting of diagnostic studies is warranted.

ROC analysis for diagnostic accuracy of fracture by using different monitors.

PubMed

Liang, Zhigang; Li, Kuncheng; Yang, Xiaolin; Du, Xiangying; Liu, Jiabin; Zhao, Xin; Qi, Xiangdong

2006-09-01

The purpose of this study was to compare diagnostic accuracy by using two types of monitors. Four radiologists with 10 years experience twice interpreted the films of 77 fracture cases by using the ViewSonic P75f+ and BARCO MGD221 monitors, with a time interval of 3 weeks. Each time the radiologists used one type of monitor to interpret the images. The image browser used was the Unisight software provided by Atlastiger Company (Shanghai, China), and interpretation result was analyzed via the LABMRMC software. In studies of receiver operating characteristics to score the presence or absence of fracture, the results of images interpreted through monochromic monitors showed significant statistical difference compared to those interpreted using the color monitors. A significant difference was observed in the results obtained by using two kinds of monitors. Color monitors cannot serve as substitutes for monochromatic monitors in the process of interpreting computed radiography (CR) images with fractures.

Cost-effectiveness analysis of microscopic observation drug susceptibility test versus Xpert MTB/Rif test for diagnosis of pulmonary tuberculosis in HIV patients in Uganda.

PubMed

Walusimbi, Simon; Kwesiga, Brendan; Rodrigues, Rashmi; Haile, Melles; de Costa, Ayesha; Bogg, Lennart; Katamba, Achilles

2016-10-10

Microscopic Observation Drug Susceptibility (MODS) and Xpert MTB/Rif (Xpert) are highly sensitive tests for diagnosis of pulmonary tuberculosis (PTB). This study evaluated the cost effectiveness of utilizing MODS versus Xpert for diagnosis of active pulmonary TB in HIV infected patients in Uganda. A decision analysis model comparing MODS versus Xpert for TB diagnosis was used. Costs were estimated by measuring and valuing relevant resources required to perform the MODS and Xpert tests. Diagnostic accuracy data of the tests were obtained from systematic reviews involving HIV infected patients. We calculated base values for unit costs and varied several assumptions to obtain the range estimates. Cost effectiveness was expressed as costs per TB patient diagnosed for each of the two diagnostic strategies. Base case analysis was performed using the base estimates for unit cost and diagnostic accuracy of the tests. Sensitivity analysis was performed using a range of value estimates for resources, prevalence, number of tests and diagnostic accuracy. The unit cost of MODS was US$ 6.53 versus US$ 12.41 of Xpert. Consumables accounted for 59 % (US$ 3.84 of 6.53) of the unit cost for MODS and 84 % (US$10.37 of 12.41) of the unit cost for Xpert. The cost effectiveness ratio of the algorithm using MODS was US$ 34 per TB patient diagnosed compared to US$ 71 of the algorithm using Xpert. The algorithm using MODS was more cost-effective compared to the algorithm using Xpert for a wide range of different values of accuracy, cost and TB prevalence. The cost (threshold value), where the algorithm using Xpert was optimal over the algorithm using MODS was US$ 5.92. MODS versus Xpert was more cost-effective for the diagnosis of PTB among HIV patients in our setting. Efforts to scale-up MODS therefore need to be explored. However, since other non-economic factors may still favour the use of Xpert, the current cost of the Xpert cartridge still needs to be reduced further by more than half, in order to make it economically competitive with MODS.

Prediction of Tubal Ectopic Pregnancy Using Offline Analysis of 3-Dimensional Transvaginal Ultrasonographic Data Sets: An Interobserver and Diagnostic Accuracy Study.

PubMed

Infante, Fernando; Espada Vaquero, Mercedes; Bignardi, Tommaso; Lu, Chuan; Testa, Antonia C; Fauchon, David; Epstein, Elisabeth; Leone, Francesco P G; Van den Bosch, Thierry; Martins, Wellington P; Condous, George

2018-06-01

To assess interobserver reproducibility in detecting tubal ectopic pregnancies by reading data sets from 3-dimensional (3D) transvaginal ultrasonography (TVUS) and comparing it with real-time 2-dimensional (2D) TVUS. Images were initially classified as showing pregnancies of unknown location or tubal ectopic pregnancies on real time 2D TVUS by an experienced sonologist, who acquired 5 3D volumes. Data sets were analyzed offline by 5 observers who had to classify each case as ectopic pregnancy or pregnancy of unknown location. The interobserver reproducibility was evaluated by the Fleiss κ statistic. The performance of each observer in predicting ectopic pregnancies was compared to that of the experienced sonologist. Women were followed until they were reclassified as follows: (1) failed pregnancy of unknown location; (2) intrauterine pregnancy; (3) ectopic pregnancy; or (4) persistent pregnancy of unknown location. Sixty-one women were included. The agreement between reading offline 3D data sets and the first real-time 2D TVUS was very good (80%-82%; κ = 0.89). The overall interobserver agreement among observers reading offline 3D data sets was moderate (κ = 0.52). The diagnostic performance of experienced observers reading offline 3D data sets had accuracy of 78.3% to 85.0%, sensitivity of 66.7% to 81.3%, specificity of 79.5% to 88.4%, positive predictive value of 57.1% to 72.2%, and negative predictive value of 87.5% to 91.3%, compared to the experienced sonologist's real-time 2D TVUS: accuracy of 94.5%, sensitivity of 94.4%, specificity of 94.5%, positive predictive value of 85.0%, and negative predictive value of 98.1%. The diagnostic accuracy of 3D TVUS by reading offline data sets for predicting ectopic pregnancies is dependent on experience. Reading only static 3D data sets without clinical information does not match the diagnostic performance of real time 2D TVUS combined with clinical information obtained during the scan. © 2017 by the American Institute of Ultrasound in Medicine.

Highly accurate detection of ovarian cancer using CA125 but limited improvement with serum matrix-assisted laser desorption/ionization time-of-flight mass spectrometry profiling.

PubMed

Tiss, Ali; Timms, John F; Smith, Celia; Devetyarov, Dmitry; Gentry-Maharaj, Aleksandra; Camuzeaux, Stephane; Burford, Brian; Nouretdinov, Ilia; Ford, Jeremy; Luo, Zhiyuan; Jacobs, Ian; Menon, Usha; Gammerman, Alex; Cramer, Rainer

2010-12-01

Our objective was to test the performance of CA125 in classifying serum samples from a cohort of malignant and benign ovarian cancers and age-matched healthy controls and to assess whether combining information from matrix-assisted laser desorption/ionization (MALDI) time-of-flight profiling could improve diagnostic performance. Serum samples from women with ovarian neoplasms and healthy volunteers were subjected to CA125 assay and MALDI time-of-flight mass spectrometry (MS) profiling. Models were built from training data sets using discriminatory MALDI MS peaks in combination with CA125 values and tested their ability to classify blinded test samples. These were compared with models using CA125 threshold levels from 193 patients with ovarian cancer, 290 with benign neoplasm, and 2236 postmenopausal healthy controls. Using a CA125 cutoff of 30 U/mL, an overall sensitivity of 94.8% (96.6% specificity) was obtained when comparing malignancies versus healthy postmenopausal controls, whereas a cutoff of 65 U/mL provided a sensitivity of 83.9% (99.6% specificity). High classification accuracies were obtained for early-stage cancers (93.5% sensitivity). Reasons for high accuracies include recruitment bias, restriction to postmenopausal women, and inclusion of only primary invasive epithelial ovarian cancer cases. The combination of MS profiling information with CA125 did not significantly improve the specificity/accuracy compared with classifications on the basis of CA125 alone. We report unexpectedly good performance of serum CA125 using threshold classification in discriminating healthy controls and women with benign masses from those with invasive ovarian cancer. This highlights the dependence of diagnostic tests on the characteristics of the study population and the crucial need for authors to provide sufficient relevant details to allow comparison. Our study also shows that MS profiling information adds little to diagnostic accuracy. This finding is in contrast with other reports and shows the limitations of serum MS profiling for biomarker discovery and as a diagnostic tool.

Effect of Needle Size in Ultrasound-guided Core Needle Breast Biopsy: Comparison of 14-, 16-, and 18-Gauge Needles.

PubMed

Giuliani, Michela; Rinaldi, Pierluigi; Rella, Rossella; Fabrizi, Gina; Petta, Federica; Carlino, Giorgio; Di Leone, Alba; Mulè, Antonino; Bufi, Enida; Romani, Maurizio; Belli, Paolo; Bonomo, Lorenzo

2017-11-01

The aim of the present study was to assess the diagnostic accuracy of ultrasound-guided core needle biopsy (US-CNB) of breast lesions, comparing smaller needles (16- and 18-gauge) with the 14-gauge needle, and to analyze the lesion characteristics influencing US-CNB diagnostic performance. All the patients provided informed consent before the biopsy procedure. The data from breast lesions that had undergone US-CNB in our institution from January 2011 to January 2015 were retrospectively reviewed. The inclusion criterion was the surgical histopathologic examination findings of the entire lesion or radiologic follow-up data for ≥ 24 months. The exclusion criterion was the use of preoperative neoadjuvant therapy. The US-CNB results were compared with the surgical pathologic results or with the follow-up findings in the 3 needle size groups (14-, 16-, and 18-gauge). The needle size- and lesion characteristic-specific diagnostic accuracy parameters were evaluated. Statistical analysis was performed using a dedicated software program, and P ≤ .01 was considered significant. A total of 1118 US-CNB cases (1042 patients) were included. Of the 1118 cases, 630 (56.3%) were in the 14-gauge group, 136 (12.2%) in the 16-gauge, and 352 (31.5%) in the 18-gauge needle group. Surgery was performed on 800 lesions (71.6%). Of these, 619 were malignant, 77 were high risk, and 104 were benign. The remaining 318 lesions (28.4%) underwent follow-up imaging studies. All the lesions were stable and, therefore, were considered benign. No differences were observed in the diagnostic accuracy parameters among the 3 needle size groups (P > .01). The false-negative rate was greater for lesions < 10 mm (7.2%) (P < .01) but without statistically significant differences among the 3 gauges (P > .01). US-CNB performed with small needles (16 and 18 gauge) had the same diagnostic accuracy as that performed with 14-gauge needles, regardless of the lesion characteristics. Copyright © 2017 Elsevier Inc. All rights reserved.

Diagnostic accuracy of ultrasonography, MRI and MR arthrography in the characterisation of rotator cuff disorders: a systematic review and meta-analysis

PubMed Central

Roy, Jean-Sébastien; Braën, Caroline; Leblond, Jean; Desmeules, François; Dionne, Clermont E; MacDermid, Joy C; Bureau, Nathalie J; Frémont, Pierre

2015-01-01

Background Different diagnostic imaging modalities, such as ultrasonography (US), MRI, MR arthrography (MRA) are commonly used for the characterisation of rotator cuff (RC) disorders. Since the most recent systematic reviews on medical imaging, multiple diagnostic studies have been published, most using more advanced technological characteristics. The first objective was to perform a meta-analysis on the diagnostic accuracy of medical imaging for characterisation of RC disorders. Since US is used at the point of care in environments such as sports medicine, a secondary analysis assessed accuracy by radiologists and non-radiologists. Methods A systematic search in three databases was conducted. Two raters performed data extraction and evaluation of risk of bias independently, and agreement was achieved by consensus. Hierarchical summary receiver-operating characteristic package was used to calculate pooled estimates of included diagnostic studies. Results Diagnostic accuracy of US, MRI and MRA in the characterisation of full-thickness RC tears was high with overall estimates of sensitivity and specificity over 0.90. As for partial RC tears and tendinopathy, overall estimates of specificity were also high (>0.90), while sensitivity was lower (0.67–0.83). Diagnostic accuracy of US was similar whether a trained radiologist, sonographer or orthopaedist performed it. Conclusions Our results show the diagnostic accuracy of US, MRI and MRA in the characterisation of full-thickness RC tears. Since full thickness tear constitutes a key consideration for surgical repair, this is an important characteristic when selecting an imaging modality for RC disorder. When considering accuracy, cost, and safety, US is the best option. PMID:25677796

Simultaneous inter-arm and inter-leg systolic blood pressure differences to diagnose peripheral artery disease: a diagnostic accuracy study.

PubMed

Herráiz-Adillo, Ángel; Soriano-Cano, Alba; Martínez-Hortelano, José Alberto; Garrido-Miguel, Miriam; Mariana-Herráiz, Julián Ángel; Martínez-Vizcaíno, Vicente; Notario-Pacheco, Blanca

2018-04-01

Inter-arm systolic blood pressure differences (IASBPD) and inter-leg systolic blood pressure differences (ILSBPD) have arisen as potential tools to detect peripheral artery disease (PAD) and individuals at high cardiovascular risk. This study aims to evaluate the diagnostic accuracy of IASBPD and ILSBPD to detect PAD, and whether IASBPD or ILSBPD improves diagnostic accuracy of the oscillometric ankle-brachial index (ABI). In this prospective study, eligible for inclusion were consecutive adults, with at least one of the following cardiovascular risk factors: diabetes, dyslipidemia, hypertension, smoking habit or age ≥65. IASBPD, ILSBPD and ankle-brachial index (ABI) were measured in all participants through four-limb simultaneous oscillometric measurements and compared with Doppler ABI (reference test, positive cut-off: ≤ 0.9). Of 171 subjects included, PAD was confirmed in 23 and excluded in 148. Thirteen and 38 subjects had IASBPD and ILSBPD ≥10 mmHg, respectively. Pearson correlation with Doppler ABI of IASBPD and ILSBPD was 0.073 (P = .343) and -0.628 (P < .001), respectively. Diagnostic accuracy of an ILSBPD ≥10 mmHg to detect PAD was: sensitivity = 69.6% (95%CI = 48.6-90.5), specificity = 85.1% (79.1-91.2), diagnostic odds ratio (dOR) = 13.1 (4.8-35.5) and area under ROC curve (AUC) = 0.765 (0.616-0.915). IASBPD had an AUC = 0.532 (0.394-0.669), and oscillometric ABI had an AUC = 0.977 (0.950-1.000). The addition of ILSBPD to oscillometric ABI reduced dOR from 174.0 (38.3-789.9) to 34.4 (9.5-125.1). Similarly, the addition of IASBPD reduced dOR to 49.3 (14.6-167.0). In a Primary Care population with ≥1 cardiovascular risk factors, ILSBPD showed acceptable diagnostic accuracy for PAD, whilst IASBPD accuracy was negligible. However, the combination of ILSBPD (or IASBPD) with oscillometric ABI did not improve the ability to detect PAD. Thus, oscillometer ABI seems to be preferable to detect PAD and individuals at high cardiovascular risk. ILSBPD could be uniquely recommended for the diagnosis of PAD when blood pressure measurements in upper limbs are not possible.

Influence of left ventricular hypertrophy and geometry on diagnostic accuracy of wall motion and perfusion magnetic resonance during dobutamine stress.

PubMed

Gebker, Rolf; Mirelis, Jesus G; Jahnke, Cosima; Hucko, Thomas; Manka, Robert; Hamdan, Ashraf; Schnackenburg, Bernhard; Fleck, Eckart; Paetsch, Ingo

2010-09-01

The purpose of this study was to determine the influence of left ventricular (LV) hypertrophy and geometry on the diagnostic accuracy of wall motion and additional perfusion imaging during high-dose dobutamine/atropine stress magnetic resonance for the detection of coronary artery disease. Combined dobutamine stress magnetic resonance (DSMR)-wall motion and DSMR-perfusion imaging was performed in a single session in 187 patients scheduled for invasive coronary angiography. Patients were classified into 4 categories on the basis of LV mass (normal, ≤ 81 g/m(2) in men and ≤ 62 g/m(2) in women) and relative wall thickness (RWT) (normal, <0.45) as follows: normal geometry (normal mass, normal RWT), concentric remodeling (normal mass, increased RWT), concentric hypertrophy (increased mass, increased RWT), and eccentric hypertrophy (increased mass, normal RWT). Wall motion and perfusion images were interpreted sequentially, with observers blinded to other data. Significant coronary artery disease was defined as ≥ 70% stenosis. In patients with increased LV concentricity (defined by an RWT ≥ 0.45), sensitivity and accuracy of DSMR-wall motion were significantly reduced (63% and 73%, respectively; P<0.05) compared with patients without increased LV concentricity (90% and 88%, respectively; P<0.05). Although accuracy of DSMR-perfusion was higher than that of DSMR-wall motion in patients with concentric hypertrophy (82% versus 71%; P < 0.05), accuracy of DSMR-wall motion was superior to DSMR-perfusion (90% versus 85%; P < 0.05) in patients with eccentric hypertrophy. The accuracy of DSMR-wall motion is influenced by LV geometry. In patients with concentric remodeling and concentric hypertrophy, additional first-pass perfusion imaging during high-dose dobutamine stress improves the diagnostic accuracy for the detection of coronary artery disease.

Staging of colorectal liver metastases after preoperative chemotherapy. Diffusion-weighted imaging in combination with Gd-EOB-DTPA MRI sequences increases sensitivity and diagnostic accuracy.

PubMed

Macera, Annalisa; Lario, Chiara; Petracchini, Massimo; Gallo, Teresa; Regge, Daniele; Floriani, Irene; Ribero, Dario; Capussotti, Lorenzo; Cirillo, Stefano

2013-03-01

To compare the diagnostic accuracy and sensitivity of Gd-EOB-DTPA MRI and diffusion-weighted (DWI) imaging alone and in combination for detecting colorectal liver metastases in patients who had undergone preoperative chemotherapy. Thirty-two consecutive patients with a total of 166 liver lesions were retrospectively enrolled. Of the lesions, 144 (86.8 %) were metastatic at pathology. Three image sets (1, Gd-EOB-DTPA; 2, DWI; 3, combined Gd-EOB-DTPA and DWI) were independently reviewed by two observers. Statistical analysis was performed on a per-lesion basis. Evaluation of image set 1 correctly identified 127/166 lesions (accuracy 76.5 %; 95 % CI 69.3-82.7) and 106/144 metastases (sensitivity 73.6 %, 95 % CI 65.6-80.6). Evaluation of image set 2 correctly identified 108/166 (accuracy 65.1 %, 95 % CI 57.3-72.3) and 87/144 metastases (sensitivity of 60.4 %, 95 % CI 51.9-68.5). Evaluation of image set 3 correctly identified 148/166 (accuracy 89.2 %, 95 % CI 83.4-93.4) and 131/144 metastases (sensitivity 91 %, 95 % CI 85.1-95.1). Differences were statistically significant (P < 0.001). Notably, similar results were obtained analysing only small lesions (<1 cm). The combination of DWI with Gd-EOB-DTPA-enhanced MRI imaging significantly increases the diagnostic accuracy and sensitivity in patients with colorectal liver metastases treated with preoperative chemotherapy, and it is particularly effective in the detection of small lesions.

Urine sampling techniques in symptomatic primary-care patients: a diagnostic accuracy review.

PubMed

Holm, Anne; Aabenhus, Rune

2016-06-08

Choice of urine sampling technique in urinary tract infection may impact diagnostic accuracy and thus lead to possible over- or undertreatment. Currently no evidencebased consensus exists regarding correct sampling technique of urine from women with symptoms of urinary tract infection in primary care. The aim of this study was to determine the accuracy of urine culture from different sampling-techniques in symptomatic non-pregnant women in primary care. A systematic review was conducted by searching Medline and Embase for clinical studies conducted in primary care using a randomized or paired design to compare the result of urine culture obtained with two or more collection techniques in adult, female, non-pregnant patients with symptoms of urinary tract infection. We evaluated quality of the studies and compared accuracy based on dichotomized outcomes. We included seven studies investigating urine sampling technique in 1062 symptomatic patients in primary care. Mid-stream-clean-catch had a positive predictive value of 0.79 to 0.95 and a negative predictive value close to 1 compared to sterile techniques. Two randomized controlled trials found no difference in infection rate between mid-stream-clean-catch, mid-stream-urine and random samples. At present, no evidence suggests that sampling technique affects the accuracy of the microbiological diagnosis in non-pregnant women with symptoms of urinary tract infection in primary care. However, the evidence presented is in-direct and the difference between mid-stream-clean-catch, mid-stream-urine and random samples remains to be investigated in a paired design to verify the present findings.

Utility of Endoanal Ultrasonography in Assessment of Primary and Recurrent Anal Fistulas and for Detection of Associated Anal Sphincter Defects.

PubMed

Emile, Sameh Hany; Magdy, Alaa; Youssef, Mohamed; Thabet, Waleed; Abdelnaby, Mahmoud; Omar, Waleed; Khafagy, Wael

2017-11-01

Tridimensional endoanal ultrasonography (3D-EAUS) has been used for the assessment of various anorectal lesions. Previous studies have reported good accuracy of 3D-EAUS in preoperative assessment of fistula-in-ano (FIA). This study aimed to assess the diagnostic utility of 3D-EAUS in preoperative evaluation of primary and recurrent FIA and its role in detection of associated anal sphincter (AS) defects. Prospectively collected data of patients with FIA who were investigated with 3D-EAUS were reviewed. The findings of EAUS were compared with the intraoperative findings, the reference standard, to find the degree of agreement regarding the position of the internal opening (IO) and primary tract (PT), and presence of secondary tracts using kappa (k) coefficient test. A subgroup analysis was performed to compare the accuracy and sensitivity of EAUS for primary and recurrent FIA. Of the patients, 131 were included to the study. EAUS had an overall accuracy of 87, 88.5, and 89.5% in detection of IO, PT, and AS defects, respectively. There was very good concordance between the findings of EAUS and intraoperative findings for the investigated parameters (kappa = 0.748, 0.83, 0.935), respectively. Accuracy and sensitivity of EAUS in recurrent FIA were insignificantly lower than primary cases. EAUS detected occult AS defects in 5.3% of the patients studied. The diagnostic utility of 3D-EAUS was comparable in primary and recurrent FIA. 3D-EAUS was able to detect symptomatic and occult AS defects with higher accuracy than clinical examination.

Diagnostic accuracy of history, physical examination, and bedside ultrasound for diagnosis of extremity fractures in the emergency department: a systematic review.

PubMed

Joshi, Nikita; Lira, Alena; Mehta, Ninfa; Paladino, Lorenzo; Sinert, Richard

2013-01-01

Understanding history, physical examination, and ultrasonography (US) to diagnose extremity fractures compared with radiography has potential benefits of decreasing radiation exposure, costs, and pain and improving emergency department (ED) resource management and triage time. The authors performed two electronic searches using PubMed and EMBASE databases for studies published between 1965 to 2012 using a strategy based on the inclusion of any patient presenting with extremity injuries suspicious for fracture who had history and physical examination and a separate search for US performed by an emergency physician (EP) with subsequent radiography. The primary outcome was operating characteristics of ED history, physical examination, and US in diagnosing radiologically proven extremity fractures. The methodologic quality of the studies was assessed using the quality assessment of studies of diagnostic accuracy tool (QUADAS-2). Nine studies met the inclusion criteria for history and physical examination, while eight studies met the inclusion criteria for US. There was significant heterogeneity in the studies that prevented data pooling. Data were organized into subgroups based on anatomic fracture locations, but heterogeneity within the subgroups also prevented data pooling. The prevalence of fracture varied among the studies from 22% to 70%. Upper extremity physical examination tests have positive likelihood ratios (LRs) ranging from 1.2 to infinity and negative LRs ranging from 0 to 0.8. US sensitivities varied between 85% and 100%, specificities varied between 73% and 100%, positive LRs varied between 3.2 and 56.1, and negative LRs varied between 0 and 0.2. Compared with radiography, EP US is an accurate diagnostic test to rule in or rule out extremity fractures. The diagnostic accuracy for history and physical examination are inconclusive. Future research is needed to understand the accuracy of ED US when combined with history and physical examination for upper and lower extremity fractures. © 2013 by the Society for Academic Emergency Medicine.

The diagnostic accuracy of 1.5T magnetic resonance imaging for detecting root avulsions in traumatic adult brachial plexus injuries.

PubMed

Wade, Ryckie G; Itte, Vinay; Rankine, James J; Ridgway, John P; Bourke, Grainne

2018-03-01

Identification of root avulsions is of critical importance in traumatic brachial plexus injuries because it alters the reconstruction and prognosis. Pre-operative magnetic resonance imaging is gaining popularity, but there is limited and conflicting data on its diagnostic accuracy for root avulsion. This cohort study describes consecutive patients requiring brachial plexus exploration following trauma between 2008 and 2016. The index test was magnetic resonance imaging at 1.5 Tesla and the reference test was operative exploration of the supraclavicular plexus. Complete data from 29 males was available. The diagnostic accuracy of magnetic resonance imaging for root avulsion(s) of C5-T1 was 79%. The diagnostic accuracy of a pseudomeningocoele as a surrogate marker of root avulsion(s) of C5-T1 was 68%. We conclude that pseudomeningocoles were not a reliable sign of root avulsion and magnetic resonance imaging has modest diagnostic accuracy for root avulsions in the context of adult traumatic brachial plexus injuries. III.

Accuracy of endoscopic ultrasonography for diagnosing ulcerative early gastric cancers

PubMed Central

Park, Jin-Seok; Kim, Hyungkil; Bang, Byongwook; Kwon, Kyesook; Shin, Youngwoon

2016-01-01

Abstract Although endoscopic ultrasonography (EUS) is the first-choice imaging modality for predicting the invasion depth of early gastric cancer (EGC), the prediction accuracy of EUS is significantly decreased when EGC is combined with ulceration. The aim of present study was to compare the accuracy of EUS and conventional endoscopy (CE) for determining the depth of EGC. In addition, the various clinic-pathologic factors affecting the diagnostic accuracy of EUS, with a particular focus on endoscopic ulcer shapes, were evaluated. We retrospectively reviewed data from 236 consecutive patients with ulcerative EGC. All patients underwent EUS for estimating tumor invasion depth, followed by either curative surgery or endoscopic treatment. The diagnostic accuracy of EUS and CE was evaluated by comparing the final histologic result of resected specimen. The correlation between accuracy of EUS and characteristics of EGC (tumor size, histology, location in stomach, tumor invasion depth, and endoscopic ulcer shapes) was analyzed. Endoscopic ulcer shapes were classified into 3 groups: definite ulcer, superficial ulcer, and ill-defined ulcer. The overall accuracy of EUS and CE for predicting the invasion depth in ulcerative EGC was 68.6% and 55.5%, respectively. Of the 236 patients, 36 patients were classified as definite ulcers, 98 were superficial ulcers, and 102 were ill-defined ulcers, In univariate analysis, EUS accuracy was associated with invasion depth (P = 0.023), tumor size (P = 0.034), and endoscopic ulcer shapes (P = 0.001). In multivariate analysis, there is a significant association between superficial ulcer in CE and EUS accuracy (odds ratio: 2.977; 95% confidence interval: 1.255–7.064; P = 0.013). The accuracy of EUS for determining tumor invasion depth in ulcerative EGC was superior to that of CE. In addition, ulcer shape was an important factor that affected EUS accuracy. PMID:27472672

Risk-adjusted capitation based on the Diagnostic Cost Group Model: an empirical evaluation with health survey information.

PubMed Central

Lamers, L M

1999-01-01

OBJECTIVE: To evaluate the predictive accuracy of the Diagnostic Cost Group (DCG) model using health survey information. DATA SOURCES/STUDY SETTING: Longitudinal data collected for a sample of members of a Dutch sickness fund. In the Netherlands the sickness funds provide compulsory health insurance coverage for the 60 percent of the population in the lowest income brackets. STUDY DESIGN: A demographic model and DCG capitation models are estimated by means of ordinary least squares, with an individual's annual healthcare expenditures in 1994 as the dependent variable. For subgroups based on health survey information, costs predicted by the models are compared with actual costs. Using stepwise regression procedures a subset of relevant survey variables that could improve the predictive accuracy of the three-year DCG model was identified. Capitation models were extended with these variables. DATA COLLECTION/EXTRACTION METHODS: For the empirical analysis, panel data of sickness fund members were used that contained demographic information, annual healthcare expenditures, and diagnostic information from hospitalizations for each member. In 1993, a mailed health survey was conducted among a random sample of 15,000 persons in the panel data set, with a 70 percent response rate. PRINCIPAL FINDINGS: The predictive accuracy of the demographic model improves when it is extended with diagnostic information from prior hospitalizations (DCGs). A subset of survey variables further improves the predictive accuracy of the DCG capitation models. The predictable profits and losses based on survey information for the DCG models are smaller than for the demographic model. Most persons with predictable losses based on health survey information were not hospitalized in the preceding year. CONCLUSIONS: The use of diagnostic information from prior hospitalizations is a promising option for improving the demographic capitation payment formula. This study suggests that diagnostic information from outpatient utilization is complementary to DCGs in predicting future costs. PMID:10029506

Radiological interpretation of images displayed on tablet computers: a systematic review.

PubMed

Caffery, L J; Armfield, N R; Smith, A C

2015-06-01

To review the published evidence and to determine if radiological diagnostic accuracy is compromised when images are displayed on a tablet computer and thereby inform practice on using tablet computers for radiological interpretation by on-call radiologists. We searched the PubMed and EMBASE databases for studies on the diagnostic accuracy or diagnostic reliability of images interpreted on tablet computers. Studies were screened for inclusion based on pre-determined inclusion and exclusion criteria. Studies were assessed for quality and risk of bias using Quality Appraisal of Diagnostic Reliability Studies or the revised Quality Assessment of Diagnostic Accuracy Studies tool. Treatment of studies was reported according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). 11 studies met the inclusion criteria. 10 of these studies tested the Apple iPad(®) (Apple, Cupertino, CA). The included studies reported high sensitivity (84-98%), specificity (74-100%) and accuracy rates (98-100%) for radiological diagnosis. There was no statistically significant difference in accuracy between a tablet computer and a digital imaging and communication in medicine-calibrated control display. There was a near complete consensus from authors on the non-inferiority of diagnostic accuracy of images displayed on a tablet computer. All of the included studies were judged to be at risk of bias. Our findings suggest that the diagnostic accuracy of radiological interpretation is not compromised by using a tablet computer. This result is only relevant to the Apple iPad and to the modalities of CT, MRI and plain radiography. The iPad may be appropriate for an on-call radiologist to use for radiological interpretation.

Overinterpretation and misreporting of diagnostic accuracy studies: evidence of "spin".

PubMed

Ochodo, Eleanor A; de Haan, Margriet C; Reitsma, Johannes B; Hooft, Lotty; Bossuyt, Patrick M; Leeflang, Mariska M G

2013-05-01

To estimate the frequency of distorted presentation and overinterpretation of results in diagnostic accuracy studies. MEDLINE was searched for diagnostic accuracy studies published between January and June 2010 in journals with an impact factor of 4 or higher. Articles included were primary studies of the accuracy of one or more tests in which the results were compared with a clinical reference standard. Two authors scored each article independently by using a pretested data-extraction form to identify actual overinterpretation and practices that facilitate overinterpretation, such as incomplete reporting of study methods or the use of inappropriate methods (potential overinterpretation). The frequency of overinterpretation was estimated in all studies and in a subgroup of imaging studies. Of the 126 articles, 39 (31%; 95% confidence interval [CI]: 23, 39) contained a form of actual overinterpretation, including 29 (23%; 95% CI: 16, 30) with an overly optimistic abstract, 10 (8%; 96% CI: 3%, 13%) with a discrepancy between the study aim and conclusion, and eight with conclusions based on selected subgroups. In our analysis of potential overinterpretation, authors of 89% (95% CI: 83%, 94%) of the studies did not include a sample size calculation, 88% (95% CI: 82%, 94%) did not state a test hypothesis, and 57% (95% CI: 48%, 66%) did not report CIs of accuracy measurements. In 43% (95% CI: 34%, 52%) of studies, authors were unclear about the intended role of the test, and in 3% (95% CI: 0%, 6%) they used inappropriate statistical tests. A subgroup analysis of imaging studies showed 16 (30%; 95% CI: 17%, 43%) and 53 (100%; 95% CI: 92%, 100%) contained forms of actual and potential overinterpretation, respectively. Overinterpretation and misreporting of results in diagnostic accuracy studies is frequent in journals with high impact factors. http://radiology.rsna.org/lookup/suppl/doi:10.1148/radiol.12120527/-/DC1. © RSNA, 2013.

Accuracy, image quality, and radiation dose of prospectively ECG-triggered high-pitch dual-source CT angiography in infants and children with complex coarctation of the aorta.

PubMed

Xu, Jian; Zhao, Hongliang; Wang, Xiaoying; Bai, Yuxiang; Liu, Liwen; Liu, Ying; Wei, Mengqi; Li, Jian; Zheng, Minwen

2014-10-01

To evaluate the diagnostic accuracy, image quality, and radiation dose of prospective electrocardiogram (ECG)-triggered high-pitch dual-source computed tomography (DSCT) in infants and young children with complex coarctation of the aorta (CoA). Forty pediatric patients aged < 4 years with suspected CoA underwent prospective ECG-triggered high-pitch DSCT angiography and transthoracic echocardiography (TTE). Surgery and/or conventional cardiac angiography (CCA) were performed in all patients. The diagnostic accuracy of DSCT angiography and TTE was compared to the surgical and/or CCA findings. The causes of misdiagnosis and miss were analyzed, and the advantages and limitation of both imaging modalities were evaluated. Image quality of DSCT was evaluated, and effective radiation dose was calculated. The sensitivity, specificity, positive predictive value, negative predictive value, and overall diagnostic accuracy of DSCT in evaluation of complex CoA were 92.37%, 98.51%, 97.32%, 93.57%, and 96.25%, respectively. There was a significant difference in the accuracy between DSCT and TTE (χ² = 9.9, P＜.05). For a total of 80 extracardiac anomalies, the sensitivity (98.8%, 79/80) of DSCT was greater than that of TTE (62.5%; 50 of 80). On the contrary, for 38 cardiac anomalies, the sensitivity (78.9%, 30 of 38) of DSCT was lesser than that of TTE (100%; 38 of 38). The mean score of image quality was 4.27 ± 0.73. The mean effective radiation dose was 0.20 ± 0.09 mSv. Prospective ECG-triggered high-pitch DSCT may be a clinical feasible modality in the evaluation of pediatric patients with complex CoA, providing adequate image quality, high diagnostic accuracy, and low radiation dose. Copyright © 2014 AUR. Published by Elsevier Inc. All rights reserved.

Dipyridamole stress myocardial perfusion by computed tomography in patients with left bundle branch block.

PubMed

Cabeda, Estêvan Vieira; Falcão, Andréa Maria Gomes; Soares, José; Rochitte, Carlos Eduardo; Nomura, César Higa; Ávila, Luiz Francisco Rodrigues; Parga, José Rodrigues

2015-12-01

Functional tests have limited accuracy for identifying myocardial ischemia in patients with left bundle branch block (LBBB). To assess the diagnostic accuracy of dipyridamole-stress myocardial computed tomography perfusion (CTP) by 320-detector CT in patients with LBBB using invasive quantitative coronary angiography (QCA) (stenosis ≥ 70%) as reference; to investigate the advantage of adding CTP to coronary computed tomography angiography (CTA) and compare the results with those of single photon emission computed tomography (SPECT) myocardial perfusion scintigraphy. Thirty patients with LBBB who had undergone SPECT for the investigation of coronary artery disease were referred for stress tomography. Independent examiners performed per-patient and per-coronary territory assessments. All patients gave written informed consent to participate in the study that was approved by the institution's ethics committee. The patients' mean age was 62 ± 10 years. The mean dose of radiation for the tomography protocol was 9.3 ± 4.6 mSv. With regard to CTP, the per-patient values for sensitivity, specificity, positive and negative predictive values, and accuracy were 86%, 81%, 80%, 87%, and 83%, respectively (p = 0.001). The per-territory values were 63%, 86%, 65%, 84%, and 79%, respectively (p < 0.001). In both analyses, the addition of CTP to CTA achieved higher diagnostic accuracy for detecting myocardial ischemia than SPECT (p < 0.001). The use of the stress tomography protocol is feasible and has good diagnostic accuracy for assessing myocardial ischemia in patients with LBBB.

Quality and reporting of diagnostic accuracy studies in TB, HIV and malaria: evaluation using QUADAS and STARD standards.

PubMed

Fontela, Patricia Scolari; Pant Pai, Nitika; Schiller, Ian; Dendukuri, Nandini; Ramsay, Andrew; Pai, Madhukar

2009-11-13

Poor methodological quality and reporting are known concerns with diagnostic accuracy studies. In 2003, the QUADAS tool and the STARD standards were published for evaluating the quality and improving the reporting of diagnostic studies, respectively. However, it is unclear whether these tools have been applied to diagnostic studies of infectious diseases. We performed a systematic review on the methodological and reporting quality of diagnostic studies in TB, malaria and HIV. We identified diagnostic accuracy studies of commercial tests for TB, malaria and HIV through a systematic search of the literature using PubMed and EMBASE (2004-2006). Original studies that reported sensitivity and specificity data were included. Two reviewers independently extracted data on study characteristics and diagnostic accuracy, and used QUADAS and STARD to evaluate the quality of methods and reporting, respectively. Ninety (38%) of 238 articles met inclusion criteria. All studies had design deficiencies. Study quality indicators that were met in less than 25% of the studies included adequate description of withdrawals (6%) and reference test execution (10%), absence of index test review bias (19%) and reference test review bias (24%), and report of uninterpretable results (22%). In terms of quality of reporting, 9 STARD indicators were reported in less than 25% of the studies: methods for calculation and estimates of reproducibility (0%), adverse effects of the diagnostic tests (1%), estimates of diagnostic accuracy between subgroups (10%), distribution of severity of disease/other diagnoses (11%), number of eligible patients who did not participate in the study (14%), blinding of the test readers (16%), and description of the team executing the test and management of indeterminate/outlier results (both 17%). The use of STARD was not explicitly mentioned in any study. Only 22% of 46 journals that published the studies included in this review required authors to use STARD. Recently published diagnostic accuracy studies on commercial tests for TB, malaria and HIV have moderate to low quality and are poorly reported. The more frequent use of tools such as QUADAS and STARD may be necessary to improve the methodological and reporting quality of future diagnostic accuracy studies in infectious diseases.

Quality and Reporting of Diagnostic Accuracy Studies in TB, HIV and Malaria: Evaluation Using QUADAS and STARD Standards

PubMed Central

Fontela, Patricia Scolari; Pant Pai, Nitika; Schiller, Ian; Dendukuri, Nandini; Ramsay, Andrew; Pai, Madhukar

2009-01-01

Background Poor methodological quality and reporting are known concerns with diagnostic accuracy studies. In 2003, the QUADAS tool and the STARD standards were published for evaluating the quality and improving the reporting of diagnostic studies, respectively. However, it is unclear whether these tools have been applied to diagnostic studies of infectious diseases. We performed a systematic review on the methodological and reporting quality of diagnostic studies in TB, malaria and HIV. Methods We identified diagnostic accuracy studies of commercial tests for TB, malaria and HIV through a systematic search of the literature using PubMed and EMBASE (2004–2006). Original studies that reported sensitivity and specificity data were included. Two reviewers independently extracted data on study characteristics and diagnostic accuracy, and used QUADAS and STARD to evaluate the quality of methods and reporting, respectively. Findings Ninety (38%) of 238 articles met inclusion criteria. All studies had design deficiencies. Study quality indicators that were met in less than 25% of the studies included adequate description of withdrawals (6%) and reference test execution (10%), absence of index test review bias (19%) and reference test review bias (24%), and report of uninterpretable results (22%). In terms of quality of reporting, 9 STARD indicators were reported in less than 25% of the studies: methods for calculation and estimates of reproducibility (0%), adverse effects of the diagnostic tests (1%), estimates of diagnostic accuracy between subgroups (10%), distribution of severity of disease/other diagnoses (11%), number of eligible patients who did not participate in the study (14%), blinding of the test readers (16%), and description of the team executing the test and management of indeterminate/outlier results (both 17%). The use of STARD was not explicitly mentioned in any study. Only 22% of 46 journals that published the studies included in this review required authors to use STARD. Conclusion Recently published diagnostic accuracy studies on commercial tests for TB, malaria and HIV have moderate to low quality and are poorly reported. The more frequent use of tools such as QUADAS and STARD may be necessary to improve the methodological and reporting quality of future diagnostic accuracy studies in infectious diseases. PMID:19915664

A systematic evaluation of prevalence and diagnostic accuracy of sacroiliac joint interventions.

PubMed

Simopoulos, Thomas T; Manchikanti, Laxmaiah; Singh, Vijay; Gupta, Sanjeeva; Hameed, Haroon; Diwan, Sudhir; Cohen, Steven P

2012-01-01

The contributions of the sacroiliac joint to low back and lower extremity pain have been a subject of considerable debate and research. It is generally accepted that 10% to 25% of patients with persistent mechanical low back pain below L5 have pain secondary to sacroiliac joint pathology. However, no single historical, physical exam, or radiological feature can definitively establish a diagnosis of sacroiliac joint pain. Based on present knowledge, a proper diagnosis can only be made using controlled diagnostic blocks. The diagnosis and treatment of sacroiliac joint pain continue to be characterized by wide variability and a paucity of the literature. To evaluate the accuracy of diagnostic sacroiliac joint interventions. A systematic review of diagnostic sacroiliac joint interventions. Methodological quality assessment of included studies was performed using Quality Appraisal of Reliability Studies (QAREL). Only diagnostic accuracy studies meeting at least 50% of the designated inclusion criteria were utilized for analysis. Studies scoring less than 50% are presented descriptively and analyzed critically. The level of evidence was classified as good, fair, or poor based on the quality of evidence developed by the United States Preventive Services Task Force (USPSTF). Data sources included relevant literature identified through searches of PubMed and EMBASE from 1966 to December 2011, and manual searches of the bibliographies of known primary and review articles. In this evaluation we utilized controlled local anesthetic blocks using at least 50% pain relief as the reference standard. The evidence is good for the diagnosis of sacroiliac joint pain utilizing controlled comparative local anesthetic blocks. The prevalence of sacroiliac joint pain is estimated to range between 10% and 62% based on the setting; however, the majority of analyzed studies suggest a point prevalence of around 25%, with a false-positive rate for uncontrolled blocks of approximately 20%. The evidence for provocative testing to diagnose sacroiliac joint pain was fair. The evidence for the diagnostic accuracy of imaging is limited. The limitations of this systematic review include a paucity of literature, variations in technique, and variable criterion standards for the diagnosis of sacroiliac joint pain. Based on this systematic review, the evidence for the diagnostic accuracy of sacroiliac joint injections is good, the evidence for provocation maneuvers is fair, and evidence for imaging is limited.

Quantitative Myocardial Perfusion Imaging Versus Visual Analysis in Diagnosing Myocardial Ischemia: A CE-MARC Substudy.

PubMed

Biglands, John D; Ibraheem, Montasir; Magee, Derek R; Radjenovic, Aleksandra; Plein, Sven; Greenwood, John P

2018-05-01

This study sought to compare the diagnostic accuracy of visual and quantitative analyses of myocardial perfusion cardiovascular magnetic resonance against a reference standard of quantitative coronary angiography. Visual analysis of perfusion cardiovascular magnetic resonance studies for assessing myocardial perfusion has been shown to have high diagnostic accuracy for coronary artery disease. However, only a few small studies have assessed the diagnostic accuracy of quantitative myocardial perfusion. This retrospective study included 128 patients randomly selected from the CE-MARC (Clinical Evaluation of Magnetic Resonance Imaging in Coronary Heart Disease) study population such that the distribution of risk factors and disease status was proportionate to the full population. Visual analysis results of cardiovascular magnetic resonance perfusion images, by consensus of 2 expert readers, were taken from the original study reports. Quantitative myocardial blood flow estimates were obtained using Fermi-constrained deconvolution. The reference standard for myocardial ischemia was a quantitative coronary x-ray angiogram stenosis severity of ≥70% diameter in any coronary artery of >2 mm diameter, or ≥50% in the left main stem. Diagnostic performance was calculated using receiver-operating characteristic curve analysis. The area under the curve for visual analysis was 0.88 (95% confidence interval: 0.81 to 0.95) with a sensitivity of 81.0% (95% confidence interval: 69.1% to 92.8%) and specificity of 86.0% (95% confidence interval: 78.7% to 93.4%). For quantitative stress myocardial blood flow the area under the curve was 0.89 (95% confidence interval: 0.83 to 0.96) with a sensitivity of 87.5% (95% confidence interval: 77.3% to 97.7%) and specificity of 84.5% (95% confidence interval: 76.8% to 92.3%). There was no statistically significant difference between the diagnostic performance of quantitative and visual analyses (p = 0.72). Incorporating rest myocardial blood flow values to generate a myocardial perfusion reserve did not significantly increase the quantitative analysis area under the curve (p = 0.79). Quantitative perfusion has a high diagnostic accuracy for detecting coronary artery disease but is not superior to visual analysis. The incorporation of rest perfusion imaging does not improve diagnostic accuracy in quantitative perfusion analysis. Copyright © 2018 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

Diagnostic Accuracy and Cost-Effectiveness of Alternative Methods for Detection of Soil-Transmitted Helminths in a Post-Treatment Setting in Western Kenya

PubMed Central

Kepha, Stella; Kihara, Jimmy H.; Njenga, Sammy M.; Pullan, Rachel L.; Brooker, Simon J.

2014-01-01

Objectives This study evaluates the diagnostic accuracy and cost-effectiveness of the Kato-Katz and Mini-FLOTAC methods for detection of soil-transmitted helminths (STH) in a post-treatment setting in western Kenya. A cost analysis also explores the cost implications of collecting samples during school surveys when compared to household surveys. Methods Stool samples were collected from children (n = 652) attending 18 schools in Bungoma County and diagnosed by the Kato-Katz and Mini-FLOTAC coprological methods. Sensitivity and additional diagnostic performance measures were analyzed using Bayesian latent class modeling. Financial and economic costs were calculated for all survey and diagnostic activities, and cost per child tested, cost per case detected and cost per STH infection correctly classified were estimated. A sensitivity analysis was conducted to assess the impact of various survey parameters on cost estimates. Results Both diagnostic methods exhibited comparable sensitivity for detection of any STH species over single and consecutive day sampling: 52.0% for single day Kato-Katz; 49.1% for single-day Mini-FLOTAC; 76.9% for consecutive day Kato-Katz; and 74.1% for consecutive day Mini-FLOTAC. Diagnostic performance did not differ significantly between methods for the different STH species. Use of Kato-Katz with school-based sampling was the lowest cost scenario for cost per child tested ($10.14) and cost per case correctly classified ($12.84). Cost per case detected was lowest for Kato-Katz used in community-based sampling ($128.24). Sensitivity analysis revealed the cost of case detection for any STH decreased non-linearly as prevalence rates increased and was influenced by the number of samples collected. Conclusions The Kato-Katz method was comparable in diagnostic sensitivity to the Mini-FLOTAC method, but afforded greater cost-effectiveness. Future work is required to evaluate the cost-effectiveness of STH surveillance in different settings. PMID:24810593

Diagnostic accuracy and cost-effectiveness of alternative methods for detection of soil-transmitted helminths in a post-treatment setting in western Kenya.

PubMed

Assefa, Liya M; Crellen, Thomas; Kepha, Stella; Kihara, Jimmy H; Njenga, Sammy M; Pullan, Rachel L; Brooker, Simon J

2014-05-01

This study evaluates the diagnostic accuracy and cost-effectiveness of the Kato-Katz and Mini-FLOTAC methods for detection of soil-transmitted helminths (STH) in a post-treatment setting in western Kenya. A cost analysis also explores the cost implications of collecting samples during school surveys when compared to household surveys. Stool samples were collected from children (n = 652) attending 18 schools in Bungoma County and diagnosed by the Kato-Katz and Mini-FLOTAC coprological methods. Sensitivity and additional diagnostic performance measures were analyzed using Bayesian latent class modeling. Financial and economic costs were calculated for all survey and diagnostic activities, and cost per child tested, cost per case detected and cost per STH infection correctly classified were estimated. A sensitivity analysis was conducted to assess the impact of various survey parameters on cost estimates. Both diagnostic methods exhibited comparable sensitivity for detection of any STH species over single and consecutive day sampling: 52.0% for single day Kato-Katz; 49.1% for single-day Mini-FLOTAC; 76.9% for consecutive day Kato-Katz; and 74.1% for consecutive day Mini-FLOTAC. Diagnostic performance did not differ significantly between methods for the different STH species. Use of Kato-Katz with school-based sampling was the lowest cost scenario for cost per child tested ($10.14) and cost per case correctly classified ($12.84). Cost per case detected was lowest for Kato-Katz used in community-based sampling ($128.24). Sensitivity analysis revealed the cost of case detection for any STH decreased non-linearly as prevalence rates increased and was influenced by the number of samples collected. The Kato-Katz method was comparable in diagnostic sensitivity to the Mini-FLOTAC method, but afforded greater cost-effectiveness. Future work is required to evaluate the cost-effectiveness of STH surveillance in different settings.

A computer-human interaction model to improve the diagnostic accuracy and clinical decision-making during 12-lead electrocardiogram interpretation.

PubMed

Cairns, Andrew W; Bond, Raymond R; Finlay, Dewar D; Breen, Cathal; Guldenring, Daniel; Gaffney, Robert; Gallagher, Anthony G; Peace, Aaron J; Henn, Pat

2016-12-01

The 12-lead Electrocardiogram (ECG) presents a plethora of information and demands extensive knowledge and a high cognitive workload to interpret. Whilst the ECG is an important clinical tool, it is frequently incorrectly interpreted. Even expert clinicians are known to impulsively provide a diagnosis based on their first impression and often miss co-abnormalities. Given it is widely reported that there is a lack of competency in ECG interpretation, it is imperative to optimise the interpretation process. Predominantly the ECG interpretation process remains a paper based approach and whilst computer algorithms are used to assist interpreters by providing printed computerised diagnoses, there are a lack of interactive human-computer interfaces to guide and assist the interpreter. An interactive computing system was developed to guide the decision making process of a clinician when interpreting the ECG. The system decomposes the interpretation process into a series of interactive sub-tasks and encourages the clinician to systematically interpret the ECG. We have named this model 'Interactive Progressive based Interpretation' (IPI) as the user cannot 'progress' unless they complete each sub-task. Using this model, the ECG is segmented into five parts and presented over five user interfaces (1: Rhythm interpretation, 2: Interpretation of the P-wave morphology, 3: Limb lead interpretation, 4: QRS morphology interpretation with chest lead and rhythm strip presentation and 5: Final review of 12-lead ECG). The IPI model was implemented using emerging web technologies (i.e. HTML5, CSS3, AJAX, PHP and MySQL). It was hypothesised that this system would reduce the number of interpretation errors and increase diagnostic accuracy in ECG interpreters. To test this, we compared the diagnostic accuracy of clinicians when they used the standard approach (control cohort) with clinicians who interpreted the same ECGs using the IPI approach (IPI cohort). For the control cohort, the (mean; standard deviation; confidence interval) of the ECG interpretation accuracy was (45.45%; SD=18.1%; CI=42.07, 48.83). The mean ECG interpretation accuracy rate for the IPI cohort was 58.85% (SD=42.4%; CI=49.12, 68.58), which indicates a positive mean difference of 13.4%. (CI=4.45, 22.35) An N-1 Chi-square test of independence indicated a 92% chance that the IPI cohort will have a higher accuracy rate. Interpreter self-rated confidence also increased between cohorts from a mean of 4.9/10 in the control cohort to 6.8/10 in the IPI cohort (p=0.06). Whilst the IPI cohort had greater diagnostic accuracy, the duration of ECG interpretation was six times longer when compared to the control cohort. We have developed a system that segments and presents the ECG across five graphical user interfaces. Results indicate that this approach improves diagnostic accuracy but with the expense of time, which is a valuable resource in medical practice. Copyright © 2016 Elsevier Inc. All rights reserved.

Integration of basic sciences and clinical sciences in oral radiology education for dental students.

PubMed

Baghdady, Mariam T; Carnahan, Heather; Lam, Ernest W N; Woods, Nicole N

2013-06-01

Educational research suggests that cognitive processing in diagnostic radiology requires a solid foundation in the basic sciences and knowledge of the radiological changes associated with disease. Although it is generally assumed that dental students must acquire both sets of knowledge, little is known about the most effective way to teach them. Currently, the basic and clinical sciences are taught separately. This study was conducted to compare the diagnostic accuracy of students when taught basic sciences segregated or integrated with clinical features. Predoctoral dental students (n=51) were taught four confusable intrabony abnormalities using basic science descriptions integrated with the radiographic features or taught segregated from the radiographic features. The students were tested with diagnostic images, and memory tests were performed immediately after learning and one week later. On immediate and delayed testing, participants in the integrated basic science group outperformed those from the segregated group. A main effect of learning condition was found to be significant (p<0.05). The results of this study support the critical role of integrating biomedical knowledge in diagnostic radiology and shows that teaching basic sciences integrated with clinical features produces higher diagnostic accuracy in novices than teaching basic sciences segregated from clinical features.

Assessment of the diagnostic value of a urinary adipsin rapid strip test for pre-eclampsia: A prospective multicenter study.

PubMed

Peng, Bing; Zhang, Li; Yan, Jianying; Qi, Hongbo; Zhang, Weiyuan; Fan, Ling; Hu, Yayi; Lin, Li; Li, Xiaotian; Hu, Rong; Xie, Lan; Zhang, Jianping; Wu, Yanqiao; Li, Li; Zhou, Rong

2017-01-01

The purpose of the present study was to evaluate the clinical value of the rapid strip test of urinary adipsin for the quick diagnosis of pre-eclampsia. In a multicenter diagnostic test study, we studied the diagnostic accuracy of the rapid strip test of urinary adipsin in women presenting with pre-eclampsia. A total of 204 pre-eclampsia patients and 254 healthy pregnant women were recruited for this study, respectively. The rapid strip test of urinary adipsin was used to detect the adipsin in the urine of each patient. The diagnostic value of the rapid strip test of urinary adipsin for pre-eclampsia was demonstrated by its high sensitivity and specificity (95.10% and 97.64%, respectively). The diagnostic accuracy was 96.51%. The consistency analysis showed that the kappa value was 0.93 compared with the gold standard diagnosis of pre-eclampsia. The rapid strip test of urinary adipsin is a non-invasive test for the diagnosis of pre-eclampsia with high sensitivity and specificity. It could help the quick diagnosis of pre-eclampsia in clinical practice greatly. © 2016 Japan Society of Obstetrics and Gynecology.

Macular ganglion cell imaging study: glaucoma diagnostic accuracy of spectral-domain optical coherence tomography.

PubMed

Jeoung, Jin Wook; Choi, Yun Jeong; Park, Ki Ho; Kim, Dong Myung

2013-07-01

We evaluated the diagnostic accuracy of macular ganglion cell-inner plexiform layer (GCIPL) measurements using a high-definition optical coherence tomography (Cirrus HD-OCT) ganglion cell analysis algorithm for detecting early and moderate-to-severe glaucoma. Totals of 119 normal subjects and 306 glaucoma patients (164 patients with early glaucoma and 142 with moderate-to-severe glaucoma) were enrolled from the Macular Ganglion Cell Imaging Study. Macular GCIPL, peripapillary retinal nerve fiber layer (RNFL) thickness, and optic nerve head (ONH) parameters were measured in each subject. Areas under the receiver operating characteristic curves (AUROCs) were calculated and compared. Based on the internal normative database, the sensitivity and specificity for detecting early and moderate-to-severe glaucoma were calculated. There was no statistically significant difference between the AUROCs for the best OCT parameters. For detecting early glaucoma, the sensitivity of the Cirrus GCIPL parameters ranged from 26.8% to 73.2% and that of the Cirrus RNFL parameters ranged from 6.1% to 61.6%. For the early glaucoma group, the best parameter from the GCIPL generally had a higher sensitivity than those of the RNFL and ONH parameters with comparable specificity (P < 0.05, McNemar's test). There were no significant differences between the AUROCs for Cirrus GCIPL, RNFL, and ONH parameters, indicating that these maps have similar diagnostic potentials for glaucoma. The minimum GCIPL showed better glaucoma diagnostic performance than the other parameters at comparable specificities. However, other GCIPL parameters showed performances comparable to those of the RNFL parameters.

Diagnostic performance of dual-energy contrast-enhanced subtracted mammography in dense breasts compared to mammography alone: interobserver blind-reading analysis.

PubMed

Cheung, Yun-Chung; Lin, Yu-Ching; Wan, Yung-Liang; Yeow, Kee-Min; Huang, Pei-Chin; Lo, Yung-Feng; Tsai, Hsiu-Pei; Ueng, Shir-Hwa; Chang, Chee-Jen

2014-10-01

To analyse the accuracy of dual-energy contrast-enhanced spectral mammography in dense breasts in comparison with contrast-enhanced subtracted mammography (CESM) and conventional mammography (Mx). CESM cases of dense breasts with histological proof were evaluated in the present study. Four radiologists with varying experience in mammography interpretation blindly read Mx first, followed by CESM. The diagnostic profiles, consistency and learning curve were analysed statistically. One hundred lesions (28 benign and 72 breast malignancies) in 89 females were analysed. Use of CESM improved the cancer diagnosis by 21.2 % in sensitivity (71.5 % to 92.7 %), by 16.1 % in specificity (51.8 % to 67.9 %) and by 19.8 % in accuracy (65.9 % to 85.8 %) compared with Mx. The interobserver diagnostic consistency was markedly higher using CESM than using Mx alone (0.6235 vs. 0.3869 using the kappa ratio). The probability of a correct prediction was elevated from 80 % to 90 % after 75 consecutive case readings. CESM provided additional information with consistent improvement of the cancer diagnosis in dense breasts compared to Mx alone. The prediction of the diagnosis could be improved by the interpretation of a significant number of cases in the presence of 6 % benign contrast enhancement in this study. • DE-CESM improves the cancer diagnosis in dense breasts compared with mammography. • DE-CESM shows greater consistency than mammography alone by interobserver blind reading. • Diagnostic improvement of DE-CESM is independent of the mammographic reading experience.

Clinical diagnosis of ventilator associated pneumonia revisited: comparative validation using immediate post-mortem lung biopsies.

PubMed

Fàbregas, N; Ewig, S; Torres, A; El-Ebiary, M; Ramirez, J; de La Bellacasa, J P; Bauer, T; Cabello, H

1999-10-01

A study was undertaken to assess the diagnostic value of different clinical criteria and the impact of microbiological testing on the accuracy of clinical diagnosis of suspected ventilator associated pneumonia (VAP). Twenty five deceased mechanically ventilated patients were studied prospectively. Immediately after death, multiple bilateral lung biopsy specimens (16 specimens/patient) were obtained for histological examination and quantitative lung cultures. The presence of both histological pneumonia and positive lung cultures was used as a reference test. The presence of infiltrates on the chest radiograph and two of three clinical criteria (leucocytosis, purulent secretions, fever) had a sensitivity of 69% and a specificity of 75%; the corresponding numbers for the clinical pulmonary infection score (CPIS) were 77% and 42%. Non-invasive as well as invasive sampling techniques had comparable values. The combination of all techniques achieved a sensitivity of 85% and a specificity of 50%, and these values remained virtually unchanged despite the presence of previous treatment with antibiotics. When microbiological results were added to clinical criteria, adequate diagnoses originating from microbiological results which might have corrected false positive and false negative clinical judgements (n = 5) were countered by a similar proportion of inadequate diagnoses (n = 6). Clinical criteria had reasonable diagnostic values. CPIS was not superior to conventional clinical criteria. Non-invasive and invasive sampling techniques had diagnostic values comparable to clinical criteria. An algorithm guiding antibiotic treatment exclusively by microbiological results does not increase the overall diagnostic accuracy and carries the risk of undertreatment.

[Value of preoperative barium contrast examination for the diagnosis and operative planning in gastric cancer].

PubMed

Wang, Chang-jian; Zhao, Guang-fa; Li, Qing-guo; Chen, Jing-gui; Zhu, Kai; Shi, Ying-qiang; Fu, Hong

2010-04-01

To investigate the value of preoperative barium contrast examination for the diagnosis and operative planning in gastric cancer. Clinical data of 229 gastric cancer patients were analyzed retrospectively. Lesions were divided into three parts: the cardiac, the body, and the antrum. The diagnostic accuracy of localization and the extent of tumor between gastroscopy alone and gastroscopy plus barium contrast were compared with the results of surgical findings. The diagnostic accuracy of localization and the extent of tumor for gastroscopy in the cardiac, the body and the antrum cancers were 100% and 78.4%, 94.6% and 86.5%, 98.1% and 84.6%, respectively, while for gastroscopy plus barium contrast were 100% and 84.8%, 100% and 91.9%, 99.0% and 90.4%, respectively. The diagnostic accuracy of both the localization and the extent of tumor were not significantly different between gastroscopy alone and gastroscopy plus barium contrast (P>0.05). Diagnostic accuracy of the length of esophagus infiltrated by cardiac cancer in gastroscopy was 60.6%, while in gastroscopy plus barium contrast was 90.9%, which was significantly different (P<0.05). Gastroscopy plus barium contrast was more accurate in predicting the possibility of thoracotomy in cardiac cancer infiltrating the lower esophagus. It is necessary to perform preoperative barium contrast examination in cardiac cancer patients, so as to identify whether the lower esophagus is infiltrated and to measure the length of lesion, which can provide evidences for making a decision of thoracotomy. For gastric body and antrum cancer, there is no indication for barium contrast examination if gastroscopy findings are satisfied.

Infective endocarditis in drug addicts: role of HIV infection and the diagnostic accuracy of Duke criteria.

PubMed

Cecchi, Enrico; Imazio, Massimo; Tidu, Massimo; Forno, Davide; De Rosa, Francesco Giuseppe; Dal Conte, Ivano; Preziosi, Costantina; Lipani, Filippo; Trinchero, Rita

2007-03-01

Intravenous drug users (IVDUs) are at increased risk of infective endocarditis. Moreover, HIV infection is common in IVDUs, with a reported prevalence of 40-90%. The clinical features of IVDUs with infective endocarditis and HIV infection may be peculiar. Few data have been reported on the diagnostic accuracy of Duke criteria in IVDUs with or without HIV infection, and a comparison of these two populations is lacking. The present study aimed to compare prospectively the clinical features of patients with infective endocarditis with or without HIV infection and to evaluate the diagnostic accuracy of Duke criteria in these patients. The study population consisted of 201 consecutive adult IVDUs with a suspected infective endocarditis (102 patients with HIV infection and 99 patients without HIV infection). Infective endocarditis was the final diagnosis in 40 of 102 patients (38.2%) with HIV infection and in 55 of 99 HIV-negative patients (55.6%). Despite similar baseline features, longer vegetations were recorded in infective endocarditis without HIV infection (23.7 +/- 7.1 mm versus 13.6 +/- 6.8 mm; P = 0.001). Patients with infective endocarditis and HIV infection had a higher total mortality at 2 months (respectively 12.5% versus 1.8%; P = 0.09); almost all the deaths were recorded in patients with AIDS or a CD4 cell count below 200 per microl, and no deaths were recorded in patients with HIV infection and a CD4 cell count > 500 per microl. Despite no identical clinical features, Duke criteria had a similar sensitivity, specificity and diagnostic accuracy in IVDUs with and without HIV infection.

Accuracy of dengue clinical diagnosis with and without NS1 antigen rapid test: Comparison between human and Bayesian network model decision.

PubMed

Sa-Ngamuang, Chaitawat; Haddawy, Peter; Luvira, Viravarn; Piyaphanee, Watcharapong; Iamsirithaworn, Sopon; Lawpoolsri, Saranath

2018-06-18

Differentiating dengue patients from other acute febrile illness patients is a great challenge among physicians. Several dengue diagnosis methods are recommended by WHO. The application of specific laboratory tests is still limited due to high cost, lack of equipment, and uncertain validity. Therefore, clinical diagnosis remains a common practice especially in resource limited settings. Bayesian networks have been shown to be a useful tool for diagnostic decision support. This study aimed to construct Bayesian network models using basic demographic, clinical, and laboratory profiles of acute febrile illness patients to diagnose dengue. Data of 397 acute undifferentiated febrile illness patients who visited the fever clinic of the Bangkok Hospital for Tropical Diseases, Thailand, were used for model construction and validation. The two best final models were selected: one with and one without NS1 rapid test result. The diagnostic accuracy of the models was compared with that of physicians on the same set of patients. The Bayesian network models provided good diagnostic accuracy of dengue infection, with ROC AUC of 0.80 and 0.75 for models with and without NS1 rapid test result, respectively. The models had approximately 80% specificity and 70% sensitivity, similar to the diagnostic accuracy of the hospital's fellows in infectious disease. Including information on NS1 rapid test improved the specificity, but reduced the sensitivity, both in model and physician diagnoses. The Bayesian network model developed in this study could be useful to assist physicians in diagnosing dengue, particularly in regions where experienced physicians and laboratory confirmation tests are limited.

A COMPARATIVE STUDY OF REAL-TIME AND STATIC ULTRASONOGRAPHY DIAGNOSES FOR THE INCIDENTAL DETECTION OF DIFFUSE THYROID DISEASE.

PubMed

Kim, Dong Wook

2015-08-01

The aim of this study was to compare the diagnostic accuracy of real-time and static ultrasonography (US) for the incidental detection of diffuse thyroid disease (DTD). In 118 consecutive patients, a single radiologist performed real-time US before thyroidectomy. For static US, the same radiologist retrospectively investigated the sonographic findings on a picture-archiving and communication system after 3 months. The diagnostic categories of both real-time and static US diagnoses were determined based on the number of abnormal findings, and the diagnostic indices were calculated by a receiver operating characteristic (ROC) curve analysis using the histopathologic results as the reference standard. Histopathologic results included normal thyroid (n = 77), Hashimoto thyroiditis (n = 11), non-Hashimoto lymphocytic thyroiditis (n = 29), and diffuse hyperplasia (n = 1). Normal thyroid and DTD showed significant differences in echogenicity, echotexture, glandular margin, and vascularity on both real-time and static US. There was a positive correlation between US categories and histopathologic results in both real-time and static US. The highest diagnostic indices were obtained when the cutoff criteria of real-time and static US diagnoses were chosen as indeterminate and suspicious for DTD, respectively. The ROC curve analysis showed that real-time US was superior to static US in diagnostic accuracy. Both real-time and static US may be helpful for the detection of incidental DTD, but real-time US is superior to static US for detecting incidental DTD.

Physical examination tests for screening and diagnosis of cervicogenic headache: A systematic review.

PubMed

Rubio-Ochoa, J; Benítez-Martínez, J; Lluch, E; Santacruz-Zaragozá, S; Gómez-Contreras, P; Cook, C E

2016-02-01

It has been suggested that differential diagnosis of headaches should consist of a robust subjective examination and a detailed physical examination of the cervical spine. Cervicogenic headache (CGH) is a form of headache that involves referred pain from the neck. To our knowledge, no studies have summarized the reliability and diagnostic accuracy of physical examination tests for CGH. The aim of this study was to summarize the reliability and diagnostic accuracy of physical examination tests used to diagnose CGH. A systematic review following PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines was performed in four electronic databases (MEDLINE, Web of Science, Embase and Scopus). Full text reports concerning physical tests for the diagnosis of CGH which reported the clinometric properties for assessment of CGH, were included and screened for methodological quality. Quality Appraisal for Reliability Studies (QAREL) and Quality Assessment of Studies of Diagnostic Accuracy (QUADAS-2) scores were completed to assess article quality. Eight articles were retrieved for quality assessment and data extraction. Studies investigating diagnostic reliability of physical examination tests for CGH scored poorer on methodological quality (higher risk of bias) than those of diagnostic accuracy. There is sufficient evidence showing high levels of reliability and diagnostic accuracy of the selected physical examination tests for the diagnosis of CGH. The cervical flexion-rotation test (CFRT) exhibited both the highest reliability and the strongest diagnostic accuracy for the diagnosis of CGH. Copyright © 2015 Elsevier Ltd. All rights reserved.

A five-year experience with throat cultures.

PubMed

Shank, J C; Powell, T A

1984-06-01

This study addresses the usefulness of the throat culture in a family practice residency setting and explores the following questions: (1) Do faculty physicians clinically identify streptococcal pharyngitis better than residents? (2) With time, will residents and faculty physicians improve in their diagnostic accuracy? (3) Should the throat culture be used always, selectively, or never? A total of 3,982 throat cultures were obtained over a five-year study period with 16 percent positive for beta-hemolytic streptococci. The results were compared with the physician's clinical diagnosis of either "nonstreptococcal" (category A) or "streptococcal" (category B). Within category A, 363 of 3,023 patients had positive cultures (12 percent clinical diagnostic error rate). Within category B, 665 of 959 patients had negative cultures (69 percent clinical diagnostic error rate). Faculty were significantly better than residents in diagnosing streptococcal pharyngitis, but not in diagnosing nonstreptococcal sore throats. Neither faculty nor residents improved their diagnostic accuracy over time. Regarding age-specific recommendations, the findings support utilizing a throat culture in all children aged 2 to 15 years with sore throat, but in adults only when the physician suspects streptococcal pharyngitis.

Bivariate random-effects meta-analysis models for diagnostic test accuracy studies using arcsine-based transformations.

PubMed

Negeri, Zelalem F; Shaikh, Mateen; Beyene, Joseph

2018-05-11

Diagnostic or screening tests are widely used in medical fields to classify patients according to their disease status. Several statistical models for meta-analysis of diagnostic test accuracy studies have been developed to synthesize test sensitivity and specificity of a diagnostic test of interest. Because of the correlation between test sensitivity and specificity, modeling the two measures using a bivariate model is recommended. In this paper, we extend the current standard bivariate linear mixed model (LMM) by proposing two variance-stabilizing transformations: the arcsine square root and the Freeman-Tukey double arcsine transformation. We compared the performance of the proposed methods with the standard method through simulations using several performance measures. The simulation results showed that our proposed methods performed better than the standard LMM in terms of bias, root mean square error, and coverage probability in most of the scenarios, even when data were generated assuming the standard LMM. We also illustrated the methods using two real data sets. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

A new method to address verification bias in studies of clinical screening tests: cervical cancer screening assays as an example.

PubMed

Xue, Xiaonan; Kim, Mimi Y; Castle, Philip E; Strickler, Howard D

2014-03-01

Studies to evaluate clinical screening tests often face the problem that the "gold standard" diagnostic approach is costly and/or invasive. It is therefore common to verify only a subset of negative screening tests using the gold standard method. However, undersampling the screen negatives can lead to substantial overestimation of the sensitivity and underestimation of the specificity of the diagnostic test. Our objective was to develop a simple and accurate statistical method to address this "verification bias." We developed a weighted generalized estimating equation approach to estimate, in a single model, the accuracy (eg, sensitivity/specificity) of multiple assays and simultaneously compare results between assays while addressing verification bias. This approach can be implemented using standard statistical software. Simulations were conducted to assess the proposed method. An example is provided using a cervical cancer screening trial that compared the accuracy of human papillomavirus and Pap tests, with histologic data as the gold standard. The proposed approach performed well in estimating and comparing the accuracy of multiple assays in the presence of verification bias. The proposed approach is an easy to apply and accurate method for addressing verification bias in studies of multiple screening methods. Copyright © 2014 Elsevier Inc. All rights reserved.

A matter of accuracy. Nanobiochips in diagnostics and in research: ethical issues as value trade-offs.

PubMed

Le Roux, Ronan

2015-04-01

The paper deals with the introduction of nanotechnology in biochips. Based on interviews and theoretical reflections, it explores blind spots left by technology assessment and ethical investigations. These have focused on possible consequences of increased diffusability of a diagnostic device, neglecting both the context of research as well as increased accuracy, despite it being a more essential feature of nanobiochip projects. Also, rather than one of many parallel aspects (technical, legal and social) in innovation processes, ethics is considered here as a ubiquitous system of choices between sometimes antagonistic values. Thus, the paper investigates what is at stake when accuracy is balanced with other practical values in different contexts. Dramatic nanotechnological increase of accuracy in biochips can raise ethical issues, since it is at odds with other values such as diffusability and reliability. But those issues will not be as revolutionary as is often claimed: neither in diagnostics, because accuracy of measurements is not accuracy of diagnostics; nor in research, because a boost in measurement accuracy is not sufficient to overcome significance-chasing malpractices. The conclusion extends to methodological recommendations.

Technical evaluation of Virtual Touch™ tissue quantification and elastography in benign and malignant breast tumors

PubMed Central

JIANG, QUAN; ZHANG, YUAN; CHEN, JIAN; ZHANG, YUN-XIAO; HE, ZHU

2014-01-01

The aim of this study was to investigate the diagnostic value of the Virtual Touch™ tissue quantification (VTQ) and elastosonography technologies in benign and malignant breast tumors. Routine preoperative ultrasound, elastosonography and VTQ examinations were performed on 86 patients with breast lesions. The elastosonography score and VTQ speed grouping of each lesion were measured and compared with the pathological findings. The difference in the elastosonography score between the benign and malignant breast tumors was statistically significant (P<0.05). The detection rate for an elastosonography score of 1–3 points in benign tumors was 68.09% and that for an elastosonography score of 4–5 points in malignant tumors was 82.05%. The difference in VTQ speed values between the benign and malignant tumors was also statistically significant (P<0.05). In addition, the diagnostic accuracy of conventional ultrasound, elastosonography, VTQ technology and the combined methods showed statistically significant differences (P<0.05). The use of the three technologies in combination significantly improved the diagnostic accuracy to 91.86%. In conclusion, the combination of conventional ultrasound, elastosonography and VTQ technology can significantly improve accuracy in the diagnosis of breast cancer. PMID:25187797

Abbreviated Combined MR Protocol: A New Faster Strategy for Characterizing Breast Lesions.

PubMed

Moschetta, Marco; Telegrafo, Michele; Rella, Leonarda; Stabile Ianora, Amato Antonio; Angelelli, Giuseppe

2016-06-01

The use of an abbreviated magnetic resonance (MR) protocol has been recently proposed for cancer screening. The aim of our study is to evaluate the diagnostic accuracy of an abbreviated MR protocol combining short TI inversion recovery (STIR), turbo-spin-echo (TSE)-T2 sequences, a pre-contrast T1, and a single intermediate (3 minutes after contrast injection) post-contrast T1 sequence for characterizing breast lesions. A total of 470 patients underwent breast MR examination for screening, problem solving, or preoperative staging. Two experienced radiologists evaluated both standard and abbreviated protocols in consensus. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and diagnostic accuracy for both protocols were calculated (with the histological findings and 6-month ultrasound follow-up as the reference standard) and compared with the McNemar test. The post-processing and interpretation times for the MR images were compared with the paired t test. In 177 of 470 (38%) patients, the MR sequences detected 185 breast lesions. Standard and abbreviated protocols obtained sensitivity, specificity, diagnostic accuracy, PPV, and NPV values respectively of 92%, 92%, 92%, 68%, and 98% and of 89%, 91%, 91%, 64%, and 98% with no statistically significant difference (P < .0001). The mean post-processing and interpretation time were, respectively, 7 ± 1 minutes and 6 ± 3.2 minutes for the standard protocol and 1 ± 1.2 minutes and 2 ± 1.2 minutes for the abbreviated protocol, with a statistically significant difference (P < .01). An abbreviated combined MR protocol represents a time-saving tool for radiologists and patients with the same diagnostic potential as the standard protocol in patients undergoing breast MRI for screening, problem solving, or preoperative staging. Copyright © 2016 Elsevier Inc. All rights reserved.

Diagnostic accuracy of Xpert MTB/RIF for tuberculosis detection in different regions with different endemic burden: A systematic review and meta-analysis

PubMed Central

Li, Shiying; Liu, Bin; Peng, Mingli; Chen, Min; Yin, Wenwei; Tang, Hui; Luo, Yuxuan; Ren, Hong

2017-01-01

Purpose To estimate the diagnostic accuracy of Xpert MTB/RIF, a systematic review and meta-analysis were carried out. Methods Up to June 20, 2015, multiple databases were screened for relevant studies. Results Accordingly, 106 studies included 52,410 samples were selected. Diagnostic accuracy of Xpert MTB/RIF for TB detection was validated against either culture or a composite reference standard (CRS). Additionally, selected studies were further subgrouped in four groups based on sample’s type, subject’s age, status of HIV co-infection and smear-positivity. The overall pooled sensitivity and specificity of Xpert MTB/RIF was 0.85 (95% confidence interval [CI] 0.82–0.88) and 0.98 (95% CI 0.96–0.98), respectively, compared to culture; while it was 0.59 (95% CI 0.44–0.72) and 0.99 (95% CI 0.97–1.00) compared to CRS. The overall sensitivity was lower in countries with high TB prevalence than countries with middle/low prevalence (0.84, 95% CI: 0.80–0.88 versus 0.89, 95% CI: 0.84–0.93). Furthermore, Xpert MTB/RIF has higher sensitivity in patients with positive smears (0.99, 95% CI 0.97–0.99), in patients with pulmonary TB samples (0.87, 95% CI 0.83–0.90), in adults (0.82, 95% CI 0.76–0.86) and in HIV-positive patients (0.81, 95% CI 0.73–0.87). Conclusions Taken together, Xpert MTB/RIF is a quick and accurate diagnostic assay for TB which will significantly help the physicians to make their clinical decisions. PMID:28708844

Diagnostic Accuracy of Natriuretic Peptides for Heart Failure in Patients with Pleural Effusion: A Systematic Review and Updated Meta-Analysis

PubMed Central

Cheng, Juan-Juan; Zhao, Shi-Di; Gao, Ming-Zhu; Huang, Hong-Yu; Gu, Bing; Ma, Ping; Chen, Yan; Wang, Jun-Hong; Yang, Cheng-Jian; Yan, Zi-He

2015-01-01

Background Previous studies have reported that natriuretic peptides in the blood and pleural fluid (PF) are effective diagnostic markers for heart failure (HF). These natriuretic peptides include N-terminal pro-brain natriuretic peptide (NT-proBNP), brain natriuretic peptide (BNP), and midregion pro-atrial natriuretic peptide (MR-proANP). This systematic review and meta-analysis evaluates the diagnostic accuracy of blood and PF natriuretic peptides for HF in patients with pleural effusion. Methods PubMed and EMBASE databases were searched to identify articles published in English that investigated the diagnostic accuracy of BNP, NT-proBNP, and MR-proANP for HF. The last search was performed on 9 October 2014. The quality of the eligible studies was assessed using the revised Quality Assessment of Diagnostic Accuracy Studies tool. The diagnostic performance characteristics (sensitivity, specificity, and other measures of accuracy) were pooled and examined using a bivariate model. Results In total, 14 studies were included in the meta-analysis, including 12 studies reporting the diagnostic accuracy of PF NT-proBNP and 4 studies evaluating blood NT-proBNP. The summary estimates of PF NT-proBNP for HF had a diagnostic sensitivity of 0.94 (95% confidence interval [CI]: 0.90–0.96), specificity of 0.91 (95% CI: 0.86–0.95), positive likelihood ratio of 10.9 (95% CI: 6.4–18.6), negative likelihood ratio of 0.07 (95% CI: 0.04–0.12), and diagnostic odds ratio of 157 (95% CI: 57–430). The overall sensitivity of blood NT-proBNP for diagnosis of HF was 0.92 (95% CI: 0.86–0.95), with a specificity of 0.88 (95% CI: 0.77–0.94), positive likelihood ratio of 7.8 (95% CI: 3.7–16.3), negative likelihood ratio of 0.10 (95% CI: 0.06–0.16), and diagnostic odds ratio of 81 (95% CI: 27–241). The diagnostic accuracy of PF MR-proANP and blood and PF BNP was not analyzed due to the small number of related studies. Conclusions BNP, NT-proBNP, and MR-proANP, either in blood or PF, are effective tools for diagnosis of HF. Additional studies are needed to rigorously evaluate the diagnostic accuracy of PF and blood MR-proANP and BNP for the diagnosis of HF. PMID:26244664

Diagnostic evaluation of sentinel lymph node biopsy using indocyanine green and infrared or fluorescent imaging in gastric cancer: a systematic review and meta-analysis.

PubMed

Skubleny, Daniel; Dang, Jerry T; Skulsky, Samuel; Switzer, Noah; Tian, Chunhong; Shi, Xinzhe; de Gara, Christopher; Birch, Daniel W; Karmali, Shahzeer

2018-06-01

Sentinel node navigation surgery (SNNS) for gastric cancer using infrared visualization of indocyanine green (ICG) is intriguing because it may limit operative morbidity. We are the first to systematically review and perform meta-analysis on the diagnostic utility of ICG and infrared electronic endoscopy (IREE) or near infrared fluorescent imaging (NIFI) for SNNS exclusively in gastric cancer. A search of electronic databases MEDLINE, EMBASE, SCOPUS, Web of Science, and the Cochrane Library using search terms "gastric/stomach" AND "tumor/carcinoma/cancer/neoplasm/adenocarcinoma/malignancy" AND "indocyanine green" was completed in May 2017. Articles were selected by two independent reviewers based on the following major inclusion criteria: (1) diagnostic accuracy study design; (2) indocyanine green was injected at tumor site; (3) IREE or NIFI was used for intraoperative visualization. 327 titles or abstracts were screened. The quality of included studies was assessed using the Quality Assessment of Diagnostic Accuracy Studies-2. Ten full text studies were selected. 643 patients were identified with the majority of patients possessing T1 tumors (79.8%). Pooled identification rate, diagnostic odds ratio, sensitivity, and specificity were 0.99 (0.97-1.0), 380.0 (68.71-2101), 0.87 (0.80-0.93), and 1.00 (0.99-1.00), respectively. The summary receiver operator characteristic for ICG + IREE/NIFI demonstrated a test accuracy of 98.3%. Subgroup analysis found improved test performance for studies with low-risk QUADAS-2 scores, studies published after 2010 and submucosal ICG injection. IREE had improved diagnostic odds ratio, sensitivity, and identification rate compared to NIFI. Heterogeneity among studies ranged from low (I 2  < 25%) to high (I 2  > 75%). We found encouraging results regarding the accuracy, diagnostic odds ratio, and specificity of the test. The sensitivity was not optimal but may be improved by a strict protocol to augment the technique. Given the number and heterogeneity of studies, our results must be viewed with caution.

Rationale and design of the dual-energy computed tomography for ischemia determination compared to "gold standard" non-invasive and invasive techniques (DECIDE-Gold): A multicenter international efficacy diagnostic study of rest-stress dual-energy computed tomography angiography with perfusion.

PubMed

Truong, Quynh A; Knaapen, Paul; Pontone, Gianluca; Andreini, Daniele; Leipsic, Jonathon; Carrascosa, Patricia; Lu, Bin; Branch, Kelley; Raman, Subha; Bloom, Stephen; Min, James K

2015-10-01

Dual-energy CT (DECT) has potential to improve myocardial perfusion for physiologic assessment of coronary artery disease (CAD). Diagnostic performance of rest-stress DECT perfusion (DECTP) is unknown. DECIDE-Gold is a prospective multicenter study to evaluate the accuracy of DECT to detect hemodynamic (HD) significant CAD, as compared to fractional flow reserve (FFR) as a reference standard. Eligible participants are subjects with symptoms of CAD referred for invasive coronary angiography (ICA). Participants will undergo DECTP, which will be performed by pharmacological stress, and participants will subsequently proceed to ICA and FFR. HD-significant CAD will be defined as FFR ≤ 0.80. In those undergoing myocardial stress imaging (MPI) by positron emission tomography (PET), single photon emission computed tomography (SPECT) or cardiac magnetic resonance (CMR) imaging, ischemia will be graded by % ischemic myocardium. Blinded core laboratory interpretation will be performed for CCTA, DECTP, MPI, ICA, and FFR. Primary endpoint is accuracy of DECTP to detect ≥1 HD-significant stenosis at the subject level when compared to FFR. Secondary and tertiary endpoints are accuracies of combinations of DECTP at the subject and vessel levels compared to FFR and MPI. DECIDE-Gold will determine the performance of DECTP for diagnosing ischemia.

Decision support in psychiatry – a comparison between the diagnostic outcomes using a computerized decision support system versus manual diagnosis

PubMed Central

Bergman, Lars G; Fors, Uno GH

2008-01-01

Background Correct diagnosis in psychiatry may be improved by novel diagnostic procedures. Computerized Decision Support Systems (CDSS) are suggested to be able to improve diagnostic procedures, but some studies indicate possible problems. Therefore, it could be important to investigate CDSS systems with regard to their feasibility to improve diagnostic procedures as well as to save time. Methods This study was undertaken to compare the traditional 'paper and pencil' diagnostic method SCID1 with the computer-aided diagnostic system CB-SCID1 to ascertain processing time and accuracy of diagnoses suggested. 63 clinicians volunteered to participate in the study and to solve two paper-based cases using either a CDSS or manually. Results No major difference between paper and pencil and computer-supported diagnosis was found. Where a difference was found it was in favour of paper and pencil. For example, a significantly shorter time was found for paper and pencil for the difficult case, as compared to computer support. A significantly higher number of correct diagnoses were found in the diffilt case for the diagnosis 'Depression' using the paper and pencil method. Although a majority of the clinicians found the computer method supportive and easy to use, it took a longer time and yielded fewer correct diagnoses than with paper and pencil. Conclusion This study could not detect any major difference in diagnostic outcome between traditional paper and pencil methods and computer support for psychiatric diagnosis. Where there were significant differences, traditional paper and pencil methods were better than the tested CDSS and thus we conclude that CDSS for diagnostic procedures may interfere with diagnosis accuracy. A limitation was that most clinicians had not previously used the CDSS system under study. The results of this study, however, confirm that CDSS development for diagnostic purposes in psychiatry has much to deal with before it can be used for routine clinical purposes. PMID:18261222

Diagnostic accuracy in Family Medicine residents using a clinical decision support system (DXplain): a randomized-controlled trial.

PubMed

Martinez-Franco, Adrian Israel; Sanchez-Mendiola, Melchor; Mazon-Ramirez, Juan Jose; Hernandez-Torres, Isaias; Rivero-Lopez, Carlos; Spicer, Troy; Martinez-Gonzalez, Adrian

2018-05-07

Clinical reasoning is an essential skill in physicians, required to address the challenges of accurate patient diagnoses. The goal of the study was to compare the diagnostic accuracy in Family Medicine residents, with and without the use of a clinical decision support tool (DXplain http://www.mghlcs.org/projects/dxplain). A total of 87 first-year Family Medicine residents, training at the National Autonomous University of Mexico (UNAM) Postgraduate Studies Division in Mexico City, participated voluntarily in the study. They were randomized to a control group and an intervention group that used DXplain. Both groups solved 30 clinical diagnosis cases (internal medicine, pediatrics, gynecology and emergency medicine) in a multiple-choice question test that had validity evidence. The percent-correct score in the Diagnosis Test in the control group (44 residents) was 74.1±9.4 (mean±standard deviation) whereas the DXplain intervention group (43 residents) had a score of 82.4±8.5 (p<0.001). There were significant differences in the four knowledge content areas of the test. Family Medicine residents have appropriate diagnostic accuracy that can improve with the use of DXplain. This could help decrease diagnostic errors, improve patient safety and the quality of medical practice. The use of clinical decision support systems could be useful in educational interventions and medical practice.

Contrast-enhanced spectral mammography in patients with MRI contraindications.

PubMed

Richter, Vivien; Hatterman, Valerie; Preibsch, Heike; Bahrs, Sonja D; Hahn, Markus; Nikolaou, Konstantin; Wiesinger, Benjamin

2017-01-01

Background Contrast-enhanced spectral mammography (CESM) is a novel breast imaging technique providing comparable diagnostic accuracy to breast magnetic resonance imaging (MRI). Purpose To show that CESM in patients with MRI contraindications is feasible, accurate, and useful as a problem-solving tool, and to highlight its limitations. Material and Methods A total of 118 patients with MRI contraindications were examined by CESM. Histology was obtained in 94 lesions and used as gold standard for diagnostic accuracy calculations. Imaging data were reviewed retrospectively for feasibility, accuracy, and technical problems. The diagnostic yield of CESM as a problem-solving tool and for therapy response evaluation was reviewed separately. Results CESM was more accurate than mammography (MG) for lesion categorization (r = 0.731, P < 0.0001 vs. r = 0.279, P = 0.006) and for lesion size estimation (r = 0.738 vs. r = 0.689, P < 0.0001). Negative predictive value of CESM was significantly higher than of MG (85.71% vs. 30.77%, P < 0.0001). When used for problem-solving, CESM changed patient management in 2/8 (25%) cases. Superposition artifacts and timing problems affected diagnostic utility in 3/118 (2.5%) patients. Conclusion CESM is a feasible and accurate alternative for patients with MRI contraindications, but it is necessary to be aware of the method's technical limitations.

Critically re-evaluating a common technique: Accuracy, reliability, and confirmation bias of EMG.

PubMed

Narayanaswami, Pushpa; Geisbush, Thomas; Jones, Lyell; Weiss, Michael; Mozaffar, Tahseen; Gronseth, Gary; Rutkove, Seward B

2016-01-19

(1) To assess the diagnostic accuracy of EMG in radiculopathy. (2) To evaluate the intrarater reliability and interrater reliability of EMG in radiculopathy. (3) To assess the presence of confirmation bias in EMG. Three experienced academic electromyographers interpreted 3 compact discs with 20 EMG videos (10 normal, 10 radiculopathy) in a blinded, standardized fashion without information regarding the nature of the study. The EMGs were interpreted 3 times (discs A, B, C) 1 month apart. Clinical information was provided only with disc C. Intrarater reliability was calculated by comparing interpretations in discs A and B, interrater reliability by comparing interpretation between reviewers. Confirmation bias was estimated by the difference in correct interpretations when clinical information was provided. Sensitivity was similar to previous reports (77%, confidence interval [CI] 63%-90%); specificity was 71%, CI 56%-85%. Intrarater reliability was good (κ 0.61, 95% CI 0.41-0.81); interrater reliability was lower (κ 0.53, CI 0.35-0.71). There was no substantial confirmation bias when clinical information was provided (absolute difference in correct responses 2.2%, CI -13.3% to 17.7%); the study lacked precision to exclude moderate confirmation bias. This study supports that (1) serial EMG studies should be performed by the same electromyographer since intrarater reliability is better than interrater reliability; (2) knowledge of clinical information does not bias EMG interpretation substantially; (3) EMG has moderate diagnostic accuracy for radiculopathy with modest specificity and electromyographers should exercise caution interpreting mild abnormalities. This study provides Class III evidence that EMG has moderate diagnostic accuracy and specificity for radiculopathy. © 2015 American Academy of Neurology.

Clinical evaluation of endoscopic trimodal imaging for the detection and differentiation of colonic polyps.

PubMed

van den Broek, Frank J C; Fockens, Paul; Van Eeden, Susanne; Kara, Mohammed A; Hardwick, James C H; Reitsma, Johannes B; Dekker, Evelien

2009-03-01

Endoscopic trimodal imaging (ETMI) incorporates high-resolution endoscopy (HRE) and autofluorescence imaging (AFI) for adenoma detection, and narrow-band imaging (NBI) for differentiation of adenomas from nonneoplastic polyps. The aim of this study was to compare AFI with HRE for adenoma detection and to assess the diagnostic accuracy of NBI for differentiation of polyps. This was a randomized trial of tandem colonoscopies. The study was performed at the Academic Medical Center in Amsterdam. One hundred patients underwent colonoscopy with ETMI. Each colonic segment was examined twice for polyps, once with HRE and once with AFI, in random order per patient. All detected polyps were assessed with NBI for pit pattern and with AFI for color, and subsequently removed. Histopathology served as the gold standard for diagnosis. The main outcome measures of this study were adenoma miss-rates of AFI and HRE, and diagnostic accuracy of NBI and AFI for differentiating adenomas from nonneoplastic polyps. Among 50 patients examined with AFI first, 32 adenomas were detected initially. Subsequent inspection with HRE identified 8 additional adenomas. Among 50 patients examined with HRE first, 35 adenomas were detected initially. Successive AFI yielded 14 additional adenomas. The adenoma miss-rates of AFI and HRE therefore were 20% and 29%, respectively (P = .351). The sensitivity, specificity, and overall accuracy of NBI for differentiation were 90%, 70%, and 79%, respectively; corresponding figures for AFI were 99%, 35%, and 63%, respectively. The overall adenoma miss-rate was 25%; AFI did not significantly reduce the adenoma miss-rate compared with HRE. Both NBI and AFI had a disappointing diagnostic accuracy for polyp differentiation, although AFI had a high sensitivity.

Cost-effectiveness of coronary CT angiography in patients with chest pain: Comparison with myocardial single photon emission tomography.

PubMed

Lee, Seung-Pyo; Jang, Eun Jin; Kim, Yong-Jin; Cha, Myung-Jin; Park, Sun-Young; Song, Hyun Jin; Choi, Ji Eun; Shim, Jung-Im; Ahn, Jeonghoon; Lee, Hyun Joo

2015-01-01

Coronary CT angiography (CCTA) has been proven accurate and is incorporated in clinical recommendations for coronary artery disease (CAD) diagnosis workup, but cost-effectiveness data, especially in comparison to other methods such as myocardial single photon emission CT (SPECT) are insufficient. To compare the cost-effectiveness of CCTA and myocardial SPECT in a real-world setting. We performed a retrospective cohort study on consecutive patients with suspected CAD and a pretest probability between 10% and 90%. Test accuracy was compared by correcting referral bias to coronary angiography depending on noninvasive test results based on the Bayes' theorem and also by incorporating 1-year follow-up results. Cost-effectiveness was analyzed using test accuracy and quality-adjusted life year (QALY). The model using diagnostic accuracy used the number of patients accurately diagnosed among 1000 persons as the effect and contained only expenses for diagnostic testing as the cost. In the model using QALY, a decision tree was developed, and the time horizon was 1 year. CCTA was performed in 635 patients and SPECT in 997 patients. An accurate diagnosis per 1000 patients was achieved in 725 patients by CCTA vs 661 patients by SPECT. In the model using diagnostic accuracy, CCTA was more effective and less expensive than SPECT ($725.38 for CCTA vs $661.46 for SPECT). In the model using QALY, CCTA was generally more effective in terms of life quality (0.00221 QALY) and cost ($513) than SPECT. However, cost utility varied among subgroups, with SPECT outperforming CCTA in patients with a pretest probability of 30% to 60% (0.01890 QALY; $113). These results suggest that CCTA may be more cost-effective than myocardial SPECT. Copyright © 2015 Society of Cardiovascular Computed Tomography. Published by Elsevier Inc. All rights reserved.

Diagnostic accuracy of an identification tool for localized neuropathic pain based on the IASP criteria.

PubMed

Mayoral, Víctor; Pérez-Hernández, Concepción; Muro, Inmaculada; Leal, Ana; Villoria, Jesús; Esquivias, Ana

2018-04-27

Based on the clear neuroanatomical delineation of many neuropathic pain (NP) symptoms, a simple tool for performing a short structured clinical encounter based on the IASP diagnostic criteria was developed to identify NP. This study evaluated its accuracy and usefulness. A case-control study was performed in 19 pain clinics within Spain. A pain clinician used the experimental screening tool (the index test, IT) to assign the descriptions of non-neuropathic (nNP), non-localized neuropathic (nLNP), and localized neuropathic (LNP) to the patients' pain conditions. The reference standard was a formal clinical diagnosis provided by another pain clinician. The accuracy of the IT was compared with that of the Douleur Neuropathique en 4 questions (DN4) and the Leeds Assessment of Neuropathic Signs and Symptoms (LANSS). Six-hundred and sixty-six patients were analyzed. There was a good agreement between the IT and the reference standard (kappa =0.722). The IT was accurate in distinguishing between LNP and nLNP (83.2% sensitivity, 88.2% specificity), between LNP and the other pain categories (nLNP + nNP) (80.0% sensitivity, 90.7% specificity), and between NP and nNP (95.5% sensitivity, 89.1% specificity). The accuracy in distinguishing between NP and nNP was comparable with that of the DN4 and the LANSS. The IT took a median of 10 min to complete. A novel instrument based on an operationalization of the IASP criteria can not only discern between LNP and nLNP, but also provide a high level of diagnostic certainty about the presence of NP after a short clinical encounter.

Comparison of the diagnostic ability of blue laser imaging magnification versus pit pattern analysis for colorectal polyps.

PubMed

Nakano, Arihiro; Hirooka, Yoshiki; Yamamura, Takeshi; Watanabe, Osamu; Nakamura, Masanao; Funasaka, Kohei; Ohno, Eizaburo; Kawashima, Hiroki; Miyahara, Ryoji; Goto, Hidemi

2017-04-01

Background and study aims  There have been few evaluations of the diagnostic ability of new narrow band light observation blue laser imaging (BLI). The present prospective study compared the diagnostic ability of BLI magnification and pit pattern analysis for colorectal polyps. Patients and methods  We collected lesions prospectively, and the analysis of images was made by two endoscopists, retrospectively. A total of 799 colorectal polyps were examined by BLI magnification and pit pattern analysis at Nagoya University Hospital. The Hiroshima narrow-band imaging classification was used for BLI. Differentiation of neoplastic from non-neoplastic lesions and diagnosis of deeply invasive submucosal cancer (dSM) were compared between BLI magnification and pit pattern analysis. Type C2 in the Hiroshima classification was evaluated separately, because application of this category as an index of the depth of cancer invasion was considered difficult. Results  We analyzed 748 colorectal polyps, excluding 51 polyps that were inflammatory polyps, sessile serrated adenoma/polyps, serrated adenomas, advanced colorectal cancers, or other lesions. The accuracy of differential diagnosis between neoplastic and non-neoplastic lesions was 98.4 % using BLI magnification and 98.7 % with pit pattern analysis. In addition, the diagnostic accuracy of BLI magnification and pit pattern analysis for dSM for cancer was 89.5 % and 92.1 %, respectively. When type C2 lesions were excluded, the diagnostic accuracy of BLI for dSM was 95.9 %. The 18 type C2 lesions comprised 1 adenoma, 9 intramucosal or slightly invasive submucosal cancers, and 8 dSM. Pit pattern analysis allowed accurate diagnosis of the depth of invasion in 13 lesions (72.2 %). Conclusions  Most colorectal polyps could be diagnosed accurately by BLI magnification without pit pattern analysis, but we should add pit pattern analysis for type C2 lesions in the Hiroshima classification.

Glaucoma diagnostic performance of GDxVCC and spectralis OCT on eyes with atypical retardation pattern.

PubMed

Hoesl, Laura Maria; Tornow, Ralf P; Schrems, Wolfgang A; Horn, Folkert K; Mardin, Christian Y; Kruse, Friedrich E; Juenemann, Anselm G M; Laemmer, Robert

2013-01-01

To investigate the impact of typical scan score (TSS) on discriminating glaucomatous and healthy eyes by scanning laser polarimetry and spectral domain optical coherence tomography (SD-OCT) in 32 peripapillary sectors. One hundred two glaucoma patients and 32 healthy controls underwent standard automated perimetry, 24-hour intraocular pressure profile, optic disc photography, GDxVCC, and SD-OCT measurements. For controls, only very typical scans (TSS=100) were accepted. Glaucoma patients were divided into 3 subgroups (very typical: TSS=100; typical: 99≥TSS≥80, atypical: TSS<80). Receiver operating characteristic curves were constructed for mean retinal nerve fiber layer values, sector data, and nerve fiber indicator (NFI). Sensitivity was estimated at ≥90% specificity to compare the discriminating ability of each imaging modality. For discrimination between healthy and glaucomatous eyes with very typical scans, the NFI and inferior sector analyses 26 to 27 demonstrated the highest sensitivity at ≥90% specificity in GDxVCC and SD-OCT, respectively. For the typical and atypical groups, sensitivity at ≥90% specificity decreased for all 32 peripapillary sectors on an average by 10.9% and 17.9% for GDxVCC and by 4.9% and 0.8% for SD-OCT. For GDxVCC, diagnostic performance of peripapillary sectors decreased with lower TSS, especially in temporosuperior and inferotemporal sectors (sensitivity at ≥90% specificity decreased by 55.3% and by 37.8% in the atypical group). Diagnostic accuracy is comparable for SD-OCT and GDxVCC if typical scans (TSS=100) are investigated. Decreasing TSS is associated with a decrease in diagnostic accuracy for discriminating healthy and glaucomatous eyes by scanning laser polarimetry. NFI is less influenced than the global or sector retinal nerve fiber layer thickness. The TSS score should be included in the standard printout. Diagnostic accuracy of SD-OCT is barely influenced by low TSS.

Evaluation of Masood’s and Modified Masood’s Scoring Systems in the Cytological Diagnosis of Palpable Breast Lump Aspirates

PubMed Central

Chithrabhanu, Savithri Moothiringode

2017-01-01

Introduction Fine Needle Aspiration Cytology (FNAC) has a leading role in the assessment of breast lesions. Masood’s Scoring Index (MSI) and its modification (Modified Masood’s scoring index; MMSI) has been proposed to aid in sub-grouping breast lesions and to help in subsequent management. Aim To assess and compare the diagnostic accuracy of MSI and MMSI by subsequent correlation with histopathology. Materials and Methods The study was cross-sectional in nature and was conducted in a tertiary care setting. The study included 207 cases presenting as palpable breast lump, which had undergone FNAC and subsequent excision biopsy for histopathology. Statistical Analysis The cases were grouped into four categories as suggested by Masood et al., (MSI) and Nandini et al., (MMSI) and concordance analysis with reference to histopathological diagnosis was done. Results In comparison to MSI, MMSI showed better concordance with histopathological diagnosis and superior diagnostic accuracy in non-proliferative breast disease category (p-value = 0.046) as well as in proliferative breast disease without atypia category. The overall diagnostic accuracy of the cytological scoring was 97.5%, with 94.5% sensitivity and 100% specificity. Conclusion Though both MSI and MMSI were found effective in subcategorizing breast lesions, MMSI was found to have better concordance with histopathology. Inclusion of cellular pattern and background material may further help in increasing the accuracy. PMID:28571141

Elevations of novel cytokines in bacterial meningitis in infants.

PubMed

Srinivasan, Lakshmi; Kilpatrick, Laurie; Shah, Samir S; Abbasi, Soraya; Harris, Mary C

2018-01-01

Bacterial meningitis is challenging to diagnose in infants, especially in the common setting of antibiotic pre-treatment, which diminishes yield of cerebrospinal fluid (CSF) cultures. Prior studies of diagnostic markers have not demonstrated sufficient accuracy. Interleukin-23 (IL-23), interleukin-18 (IL-18) and soluble receptor for advanced glycation end products (sRAGE) possess biologic plausibility, and may be useful as diagnostic markers in bacterial meningitis. In a prospective cohort study, we measured IL-23, IL-18 and sRAGE levels in CSF. We compared differences between infected and non-infected infants, and conducted receiver operating characteristic (ROC) analyses to identify individual markers and combinations of markers with the best diagnostic accuracy. 189 infants <6 months, including 8 with bacterial meningitis, 30 without meningitis, and 151 with indeterminate diagnosis (due to antibiotic pretreatment) were included. CSF IL-23, IL-18 and sRAGE levels were significantly elevated in infants with culture proven meningitis. Among individual markers, IL-23 possessed the greatest accuracy for diagnosis of bacterial meningitis (area under the curve (AUC) 0.9698). The combination of all three markers had an AUC of 1. IL-23, alone and in combination with IL-18 and sRAGE, identified bacterial meningitis with excellent accuracy. Following validation, these markers could aid clinicians in diagnosis of bacterial meningitis and decision-making regarding prolongation of antibiotic therapy.

Radiological interpretation of images displayed on tablet computers: a systematic review

PubMed Central

Armfield, N R; Smith, A C

2015-01-01

Objective: To review the published evidence and to determine if radiological diagnostic accuracy is compromised when images are displayed on a tablet computer and thereby inform practice on using tablet computers for radiological interpretation by on-call radiologists. Methods: We searched the PubMed and EMBASE databases for studies on the diagnostic accuracy or diagnostic reliability of images interpreted on tablet computers. Studies were screened for inclusion based on pre-determined inclusion and exclusion criteria. Studies were assessed for quality and risk of bias using Quality Appraisal of Diagnostic Reliability Studies or the revised Quality Assessment of Diagnostic Accuracy Studies tool. Treatment of studies was reported according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). Results: 11 studies met the inclusion criteria. 10 of these studies tested the Apple iPad® (Apple, Cupertino, CA). The included studies reported high sensitivity (84–98%), specificity (74–100%) and accuracy rates (98–100%) for radiological diagnosis. There was no statistically significant difference in accuracy between a tablet computer and a digital imaging and communication in medicine-calibrated control display. There was a near complete consensus from authors on the non-inferiority of diagnostic accuracy of images displayed on a tablet computer. All of the included studies were judged to be at risk of bias. Conclusion: Our findings suggest that the diagnostic accuracy of radiological interpretation is not compromised by using a tablet computer. This result is only relevant to the Apple iPad and to the modalities of CT, MRI and plain radiography. Advances in knowledge: The iPad may be appropriate for an on-call radiologist to use for radiological interpretation. PMID:25882691

Initial derivation of diagnostic clusters combining history elements and physical examination tests for symptomatic knee osteoarthritis.

PubMed

Décary, Simon; Feldman, Debbie; Frémont, Pierre; Pelletier, Jean-Pierre; Martel-Pelletier, Johanne; Fallaha, Michel; Pelletier, Bruno; Belzile, Sylvain; Sylvestre, Marie-Pierre; Vendittoli, Pascal-André; Desmeules, François

2018-05-21

The aim of the present study was to assess the validity of clusters combining history elements and physical examination tests to diagnose symptomatic knee osteoarthritis (SOA) compared with other knee disorders. This was a prospective diagnostic accuracy study, in which 279 consecutive patients consulting for a knee complaint were assessed. History elements and standardized physical examination tests were obtained independently by a physiotherapist and compared with an expert physician's composite diagnosis, including clinical examination and imaging. Recursive partitioning was used to develop diagnostic clusters for SOA. Diagnostic accuracy measures were calculated, including sensitivity, specificity, and positive and negative likelihood ratios (LR+/-), with associated 95% confidence intervals (CIs). A total of 129 patients had a diagnosis of SOA (46.2%). Most cases (76%) had combined tibiofemoral and patellofemoral knee OA and 63% had radiological Kellgren-Lawrence grades of 2 or 3. Different combinations of history elements and physical examination tests were used in clusters accurately to discriminate SOA from other knee disorders. These included age of patients, body mass index, presence of valgus/varus knee misalignment, palpable knee crepitus and limited passive knee extension. Two clusters to rule in SOA reached an LR+ of 13.6 (95% CI 6.5 to 28.4) and three clusters to rule out SOA reached an LR- of 0.11 (95% CI 0.06 to 0.20). Diagnostic clusters combining history elements and physical examination tests were able to support the differential diagnosis of SOA compared with various knee disorders without relying systematically on imaging. This could support primary care clinicians' role in the efficient management of these patients. Copyright © 2018 John Wiley & Sons, Ltd.

Diagnostic accuracy of two multiplex real-time polymerase chain reaction assays for the diagnosis of meningitis in children in a resource-limited setting.

PubMed

Khumalo, Jermaine; Nicol, Mark; Hardie, Diana; Muloiwa, Rudzani; Mteshana, Phindile; Bamford, Colleen

2017-01-01

Accurate etiological diagnosis of meningitis is important, but difficult in resource-limited settings due to prior administration of antibiotics and lack of viral diagnostics. We aimed to develop and validate 2 real-time multiplex PCR (RT-PCR) assays for the detection of common causes of community-acquired bacterial and viral meningitis in South African children. We developed 2 multiplex RT- PCRs for detection of S. pneumoniae, N. meningitidis, H. influenzae, enteroviruses, mumps virus and herpes simplex virus. We tested residual CSF samples from children presenting to a local paediatric hospital over a one-year period, whose CSF showed an abnormal cell count. Results were compared with routine diagnostic tests and the final discharge diagnosis. We calculated accuracy of the bacterial RT-PCR assay compared to CSF culture and using World Health Organisation definitions of laboratory-confirmed bacterial meningitis. From 292 samples, bacterial DNA was detected in 12 (4.1%) and viral nucleic acids in 94 (32%). Compared to CSF culture, the sensitivity and specificity of the bacterial RT-PCR was 100% and 97.2% with complete agreement in organism identification. None of the cases positive by viral RT-PCR had a bacterial cause confirmed on CSF culture. Only 9/90 (10%) of patients diagnosed clinically as bacterial meningitis or partially treated bacterial meningitis tested positive with the bacterial RT-PCR. In this population the use of 2 multiplex RT-PCRs targeting 6 common pathogens gave promising results. If introduced into routine diagnostic testing, these multiplex RT-PCR assays would supplement other diagnostic tests, and have the potential to limit unnecessary antibiotic therapy and hospitalisation.

Diagnostic accuracy of two multiplex real-time polymerase chain reaction assays for the diagnosis of meningitis in children in a resource-limited setting

PubMed Central

Khumalo, Jermaine; Nicol, Mark; Hardie, Diana; Muloiwa, Rudzani; Mteshana, Phindile

2017-01-01

Introduction Accurate etiological diagnosis of meningitis is important, but difficult in resource-limited settings due to prior administration of antibiotics and lack of viral diagnostics. We aimed to develop and validate 2 real-time multiplex PCR (RT-PCR) assays for the detection of common causes of community-acquired bacterial and viral meningitis in South African children. Methods We developed 2 multiplex RT- PCRs for detection of S. pneumoniae, N. meningitidis, H. influenzae, enteroviruses, mumps virus and herpes simplex virus. We tested residual CSF samples from children presenting to a local paediatric hospital over a one-year period, whose CSF showed an abnormal cell count. Results were compared with routine diagnostic tests and the final discharge diagnosis. We calculated accuracy of the bacterial RT-PCR assay compared to CSF culture and using World Health Organisation definitions of laboratory-confirmed bacterial meningitis. Results From 292 samples, bacterial DNA was detected in 12 (4.1%) and viral nucleic acids in 94 (32%). Compared to CSF culture, the sensitivity and specificity of the bacterial RT-PCR was 100% and 97.2% with complete agreement in organism identification. None of the cases positive by viral RT-PCR had a bacterial cause confirmed on CSF culture. Only 9/90 (10%) of patients diagnosed clinically as bacterial meningitis or partially treated bacterial meningitis tested positive with the bacterial RT-PCR. Discussion In this population the use of 2 multiplex RT-PCRs targeting 6 common pathogens gave promising results. If introduced into routine diagnostic testing, these multiplex RT-PCR assays would supplement other diagnostic tests, and have the potential to limit unnecessary antibiotic therapy and hospitalisation. PMID:28346504

Rapid diagnostic tests to improve treatment of malaria and other febrile illnesses: patient randomised effectiveness trial in primary care clinics in Afghanistan

PubMed Central

Mikhail, Amy; Mayan, Ismail; Cundill, Bonnie; Anwar, Mohammed; Bakhtash, Sayed Habib; Mohammed, Nader; Rahman, Habib; Zekria, Rohullah; Whitty, Christopher J M; Rowland, Mark

2014-01-01

Objective To assess the impact of rapid diagnostic tests on the diagnostic accuracy and treatment of malaria and non-severe fever in an Asian setting. Design Patient randomised trial in primary level clinics. Setting Two areas of Afghanistan where Plasmodium vivax and Plasmodium falciparum are endemic; one area with moderate transmission (eastern region) and one with low transmission (northern region). Participants 5794 patients of all ages with suspected malaria enrolled by 80 clinicians in 22 clinics. Interventions Malaria rapid diagnostic tests were compared with clinical diagnosis where no parasite diagnostic test was available, longer established field microscopy, and recently introduced microscopy. Main outcome measures Proportion of patients appropriately treated with an antimalarial, defined as patients with P vivax who received chloroquine, patients with P falciparum who received artemisinin based combination therapy, and patients with no malaria parasites who did not receive an antimalarial. Secondary outcomes included diagnostic test accuracy and the proportion of patients negative for malaria who received antibiotics and antimalarials. Results In the low transmission area, comparing rapid diagnostic tests with clinical diagnosis, 65% (212/325) versus 12% (40/321) of febrile patients were appropriately treated for malaria (adjusted odds ratio 92.7, 95% confidence interval 12.4 to 694.1, P<0.001). The proportion of patients who were negative for malaria and received an antibiotic was 57% (185/325) in the rapid diagnostic test arm compared with 14% (46/321) in the clinical diagnosis arm (16.9, 3.8 to 75.4, P<0.001). In the comparison of rapid diagnostic test with microscopy in the moderate transmission area, 83.6% (1696/2028) versus 76.3% (1512/1983) of patients were appropriately treated for malaria (1.70, 1.30 to 2.23, P<0.001). A higher proportion of P falciparum cases received appropriate treatment with artemisinin based combination therapy when malaria was diagnosed by rapid diagnostic test (82%, 58/71 v 32%, 24/76; 9.2, 3.88 to 21.66, P<0.001). Conclusions In South and central Asian regions of low to moderate malaria transmission where clinics lack capacity for diagnosis with rapid diagnostic tests or microscopy, the introduction of the tests should be considered to improve clinical care, reduce the overuse of antimalarials, and improve disease surveillance. PMID:24948695

Efficacy of Transcerebellar Diameter/Abdominal Circumference Versus Head Circumference/Abdominal Circumference in Predicting Asymmetric Intrauterine Growth Retardation

PubMed Central

Bhimarao; Bhat, Venkataramana; Gowda, Puttanna VN

2015-01-01

Background The high incidence of IUGR and its low recognition lead to increasing perinatal morbidity and mortality for which prediction of IUGR with timely management decisions is of paramount importance. Many studies have compared the efficacy of several gestational age independent parameters and found that TCD/AC is a better predictor of asymmetric IUGR. Aim To compare the accuracy of transcerebellar diameter/abdominal circumference with head circumference/abdominal circumference in predicting asymmetric intrauterine growth retardation after 20 weeks of gestation. Materials and Methods The prospective study was conducted over a period of one year on 50 clinically suspected IUGR pregnancies who were evaluated with 3.5 MHz frequency ultrasound scanner by a single sonologist. BPD, HC, AC and FL along with TCD were measured for assessing the sonological gestational age. Two morphometric ratios- TCD/AC and HC/AC were calculated. Estimated fetal weight was calculated for all these pregnancies and its percentile was determined. Statistical Methods The TCD/AC and HC/AC ratios were correlated with advancing gestational age to know if these were related to GA. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and diagnostic accuracy (DA) for TCD/AC and HC/AC ratios in evaluating IUGR fetuses were calculated. Results In the present study, linear relation of TCD and HC in IUGR fetuses with gestation was noted. The sensitivity, specificity, PPV, NPV & DA were 88%, 93.5%, 77.1%, 96.3% & 92.4% respectively for TCD/AC ratio versus 84%, 92%, 72.4%, 95.8% & 90.4% respectively for HC/AC ratio in predicting IUGR. Conclusion Both ratios were gestational age independent and can be used in detecting IUGR with good diagnostic accuracy. However, TCD/AC ratio had a better diagnostic validity and accuracy compared to HC/AC ratio in predicting asymmetric IUGR. PMID:26557588

Methodology and reporting of diagnostic accuracy studies of automated perimetry in glaucoma: evaluation using a standardised approach.

PubMed

Fidalgo, Bruno M R; Crabb, David P; Lawrenson, John G

2015-05-01

To evaluate methodological and reporting quality of diagnostic accuracy studies of perimetry in glaucoma and to determine whether there had been any improvement since the publication of the Standards for Reporting of Diagnostic Accuracy (STARD) guidelines. A systematic review of English language articles published between 1993 and 2013 reporting the diagnostic accuracy of perimetry in glaucoma. Articles were appraised for methodological quality using the 14-item Quality assessment tool for diagnostic accuracy studies (QUADAS) and evaluated for quality of reporting by applying the STARD checklist. Fifty-eight articles were appraised. Overall methodological quality of these studies was moderate with a median number of QUADAS items rated as 'yes' equal to nine (out of a maximum of 14) (IQR 7-10). The studies were often poorly reported; median score of STARD items fully reported was 11 out of 25 (IQR 10-14). A comparison of the studies published in 10-year periods before and after the publication of the STARD checklist in 2003 found quality of reporting had not substantially improved. Methodological and reporting quality of diagnostic accuracy studies of perimetry is sub-optimal and appears not to have improved substantially following the development of the STARD reporting guidance. This observation is consistent with previous studies in ophthalmology and in other medical specialities. © 2015 The Authors Ophthalmic & Physiological Optics © 2015 The College of Optometrists.

Evaluating Diagnostic Accuracy of Noninvasive Tests in Assessment of Significant Liver Fibrosis in Chronic Hepatitis C Egyptian Patients.

PubMed

Omran, Dalia; Zayed, Rania A; Nabeel, Mohammed M; Mobarak, Lamiaa; Zakaria, Zeinab; Farid, Azza; Hassany, Mohamed; Saif, Sameh; Mostafa, Muhammad; Saad, Omar Khalid; Yosry, Ayman

2018-05-01

Stage of liver fibrosis is critical for treatment decision and prediction of outcomes in chronic hepatitis C (CHC) patients. We evaluated the diagnostic accuracy of transient elastography (TE)-FibroScan and noninvasive serum markers tests in the assessment of liver fibrosis in CHC patients, in reference to liver biopsy. One-hundred treatment-naive CHC patients were subjected to liver biopsy, TE-FibroScan, and eight serum biomarkers tests; AST/ALT ratio (AAR), AST to platelet ratio index (APRI), age-platelet index (AP index), fibrosis quotient (FibroQ), fibrosis 4 index (FIB-4), cirrhosis discriminant score (CDS), King score, and Goteborg University Cirrhosis Index (GUCI). Receiver operating characteristic curves were constructed to compare the diagnostic accuracy of these noninvasive methods in predicting significant fibrosis in CHC patients. TE-FibroScan predicted significant fibrosis at cutoff value 8.5 kPa with area under the receiver operating characteristic (AUROC) 0.90, sensitivity 83%, specificity 91.5%, positive predictive value (PPV) 91.2%, and negative predictive value (NPV) 84.4%. Serum biomarkers tests showed that AP index and FibroQ had the highest diagnostic accuracy in predicting significant liver fibrosis at cutoff 4.5 and 2.7, AUROC was 0.8 and 0.8 with sensitivity 73.6% and 73.6%, specificity 70.2% and 68.1%, PPV 71.1% and 69.8%, and NPV 72.9% and 72.3%, respectively. Combined AP index and FibroQ had AUROC 0.83 with sensitivity 73.6%, specificity 80.9%, PPV 79.6%, and NPV 75.7% for predicting significant liver fibrosis. APRI, FIB-4, CDS, King score, and GUCI had intermediate accuracy in predicting significant liver fibrosis with AUROC 0.68, 0.78, 0.74, 0.74, and 0.67, respectively, while AAR had low accuracy in predicting significant liver fibrosis. TE-FibroScan is the most accurate noninvasive alternative to liver biopsy. AP index and FibroQ, either as individual tests or combined, have good accuracy in predicting significant liver fibrosis, and are better combined for higher specificity.

New statistical learning theory paradigms adapted to breast cancer diagnosis/classification using image and non-image clinical data.

PubMed

Land, Walker H; Heine, John J; Raway, Tom; Mizaku, Alda; Kovalchuk, Nataliya; Yang, Jack Y; Yang, Mary Qu

2008-01-01

The automated decision paradigms presented in this work address the false positive (FP) biopsy occurrence in diagnostic mammography. An EP/ES stochastic hybrid and two kernelized Partial Least Squares (K-PLS) paradigms were investigated with following studies: methodology performance comparisonsautomated diagnostic accuracy assessments with two data sets. The findings showed: the new hybrid produced comparable results more rapidlythe new K-PLS paradigms train and operate Essentially in real time for the data sets studied. Both advancements are essential components for eventually achieving the FP reduction goal, while maintaining acceptable diagnostic sensitivities.

New statistical learning theory paradigms adapted to breast cancer diagnosis/classification using image and non-image clinical data

PubMed Central

Raway, Tom; Mizaku, Alda; Kovalchuk, Nataliya; Yang, Jack Y.; Yang, Mary Qu

2015-01-01

The automated decision paradigms presented in this work address the false positive (FP) biopsy occurrence in diagnostic mammography. An EP/ES stochastic hybrid and two kernelized Partial Least Squares (K-PLS) paradigms were investigated with following studies: methodology performance comparisonsautomated diagnostic accuracy assessments with two data sets. The findings showed: the new hybrid produced comparable results more rapidlythe new K-PLS paradigms train and operate Essentially in real time for the data sets studied. Both advancements are essential components for eventually achieving the FP reduction goal, while maintaining acceptable diagnostic sensitivities. PMID:26430470

Percutaneous transhepatic cholangiographic endobiliary forceps biopsy versus endoscopic ultrasound fine needle aspiration for proximal biliary strictures: a single-centre experience.

PubMed

Mohkam, Kayvan; Malik, Yaseen; Derosas, Carlos; Isaac, John; Marudanayagam, Ravi; Mehrzad, Homoyoon; Mirza, Darius F; Muiesan, Paolo; Roberts, Keith J; Sutcliffe, Robert P

2017-06-01

Endoscopic ultrasound fine needle aspiration (EUS-FNA) and percutaneous transhepatic cholangiographic endobiliary forceps biopsy (PTC-EFB) are valid procedures for histological assessment of proximal biliary strictures (PBS), but their performances have never been compared. This study aimed to compare the diagnostic performance of these two techniques. The diagnostic performances of EUS-FNA and PTC-EFB were compared in a retrospective cohort of patients assessed for PBS from 2011 to 2015 at a single tertiary centre. An inverse probability of treatment weighting (IPTW) was performed to adjust for covariate imbalance. A total of 102 EUS-FNAs and 75 PTC-EFBs (performed in 137 patients) were compared. Patients in the PTC-EFB group had higher preoperative bilirubin (243 versus 169 μmol/l, p = 0.005) and a higher incidence of malignancy (87% versus 67%, p = 0.008). Both techniques showed specificity and positive predictive value of 100%, and similar sensitivity (69% versus 75%, p = 0.45), negative predictive value (58% versus 38%, p = 0.15) and accuracy (78% versus 79%, p = 1.00). After IPTW, the diagnostic performance of the two techniques remained similar. Compared to EUS-FNA, PTC-EFB provides similar sensitivity, negative predictive value and accuracy. It should therefore be considered as the preferred tissue-sampling procedure, if biliary drainage is indicated. Crown Copyright © 2017. Published by Elsevier Ltd. All rights reserved.

Cost-effectiveness of PET and PET/computed tomography: a systematic review.

PubMed

Gerke, Oke; Hermansson, Ronnie; Hess, Søren; Schifter, Søren; Vach, Werner; Høilund-Carlsen, Poul Flemming

2015-01-01

The development of clinical diagnostic procedures comprises early-phase and late-phase studies to elucidate diagnostic accuracy and patient outcome. Economic assessments of new diagnostic procedures compared with established work-ups indicate additional cost for 1 additional unit of effectiveness measure by means of incremental cost-effectiveness ratios when considering the replacement of the standard regimen by a new diagnostic procedure. This article discusses economic assessments of PET and PET/computed tomography reported until mid-July 2014. Forty-seven studies on cancer and noncancer indications were identified but, because of the widely varying scope of the analyses, a substantial amount of work remains to be done. Copyright © 2015 Elsevier Inc. All rights reserved.

Diagnostic accuracy of central venous catheter confirmation by bedside ultrasound versus chest radiography in critically ill patients: A systematic review and meta-analysis

PubMed Central

Ablordeppey, Enyo A.; Drewry, Anne M.; Beyer, Alexander B.; Theodoro, Daniel L.; Fowler, Susan A.; Fuller, Brian M.; Carpenter, Christopher R.

2016-01-01

Objective We performed a systematic review and meta-analysis to examine the accuracy of bedside ultrasound for confirmation of central venous catheter position and exclusion of pneumothorax compared to chest radiography. Data Sources PubMed, EMBASE, Cochrane Central Register of Controlled Trials, reference lists, conference proceedings and ClinicalTrials.gov Study Selection Articles and abstracts describing the diagnostic accuracy of bedside ultrasound compared with chest radiography for confirmation of central venous catheters in sufficient detail to reconstruct 2×2 contingency tables were reviewed. Primary outcomes included the accuracy of confirming catheter positioning and detecting a pneumothorax. Secondary outcomes included feasibility, inter-rater reliability, and efficiency to complete bedside ultrasound confirmation of central venous catheter position. Data Extraction Investigators abstracted study details including research design and sonographic imaging technique to detect catheter malposition and procedure-related pneumothorax. Diagnostic accuracy measures included pooled sensitivity, specificity, positive likelihood ratio, and negative likelihood ratio. Data Synthesis 15 studies with 1553 central venous catheter placements were identified with a pooled sensitivity and specificity of catheter malposition by ultrasound of 0.82 [0.77, 0.86] and 0.98 [0.97, 0.99] respectively. The pooled positive and negative likelihood ratios of catheter malposition by ultrasound were 31.12 [14.72, 65.78] and 0.25 [0.13, 0.47]. The sensitivity and specificity of ultrasound for pneumothorax detection was nearly 100% in the participating studies. Bedside ultrasound reduced mean central venous catheter confirmation time by 58.3 minutes. Risk of bias and clinical heterogeneity in the studies were high. Conclusions Bedside ultrasound is faster than radiography at identifying pneumothorax after central venous catheter insertion. When a central venous catheter malposition exists, bedside ultrasound will identify four out of every five earlier than chest radiography. PMID:27922877

Can CT and MR Shape and Textural Features Differentiate Benign Versus Malignant Pleural Lesions?

PubMed

Pena, Elena; Ojiaku, MacArinze; Inacio, Joao R; Gupta, Ashish; Macdonald, D Blair; Shabana, Wael; Seely, Jean M; Rybicki, Frank J; Dennie, Carole; Thornhill, Rebecca E

2017-10-01

The study aimed to identify a radiomic approach based on CT and or magnetic resonance (MR) features (shape and texture) that may help differentiate benign versus malignant pleural lesions, and to assess if the radiomic model may improve confidence and accuracy of radiologists with different subspecialty backgrounds. Twenty-nine patients with pleural lesions studied on both contrast-enhanced CT and MR imaging were reviewed retrospectively. Three texture and three shape features were extracted. Combinations of features were used to generate logistic regression models using histopathology as outcome. Two thoracic and two abdominal radiologists evaluated their degree of confidence in malignancy. Diagnostic accuracy of radiologists was determined using contingency tables. Cohen's kappa coefficient was used to assess inter-reader agreement. Using optimal threshold criteria, sensitivity, specificity, and accuracy of each feature and combination of features were obtained and compared to the accuracy and confidence of radiologists. The CT model that best discriminated malignant from benign lesions revealed an AUC CT  = 0.92 ± 0.05 (P < 0.0001). The most discriminative MR model showed an AUC MR  = 0.87 ± 0.09 (P < 0.0001). The CT model was compared to the diagnostic confidence of all radiologists and the model outperformed both abdominal radiologists (P < 0.002), whereas the top discriminative MR model outperformed one of the abdominal radiologists (P = 0.02). The most discriminative MR model was more accurate than one abdominal (P = 0.04) and one thoracic radiologist (P = 0.02). Quantitative textural and shape analysis may help distinguish malignant from benign lesions. A radiomics-based approach may increase diagnostic confidence of abdominal radiologists on CT and MR and may potentially improve radiologists' accuracy in the assessment of pleural lesions characterized by MR. Copyright © 2017 The Association of University Radiologists. Published by Elsevier Inc. All rights reserved.

Whole-tumor histogram analysis of the cerebral blood volume map: tumor volume defined by 11C-methionine positron emission tomography image improves the diagnostic accuracy of cerebral glioma grading.

PubMed

Wu, Rongli; Watanabe, Yoshiyuki; Arisawa, Atsuko; Takahashi, Hiroto; Tanaka, Hisashi; Fujimoto, Yasunori; Watabe, Tadashi; Isohashi, Kayako; Hatazawa, Jun; Tomiyama, Noriyuki

2017-10-01

This study aimed to compare the tumor volume definition using conventional magnetic resonance (MR) and 11C-methionine positron emission tomography (MET/PET) images in the differentiation of the pre-operative glioma grade by using whole-tumor histogram analysis of normalized cerebral blood volume (nCBV) maps. Thirty-four patients with histopathologically proven primary brain low-grade gliomas (n = 15) and high-grade gliomas (n = 19) underwent pre-operative or pre-biopsy MET/PET, fluid-attenuated inversion recovery, dynamic susceptibility contrast perfusion-weighted magnetic resonance imaging, and contrast-enhanced T1-weighted at 3.0 T. The histogram distribution derived from the nCBV maps was obtained by co-registering the whole tumor volume delineated on conventional MR or MET/PET images, and eight histogram parameters were assessed. The mean nCBV value had the highest AUC value (0.906) based on MET/PET images. Diagnostic accuracy significantly improved when the tumor volume was measured from MET/PET images compared with conventional MR images for the parameters of mean, 50th, and 75th percentile nCBV value (p = 0.0246, 0.0223, and 0.0150, respectively). Whole-tumor histogram analysis of CBV map provides more valuable histogram parameters and increases diagnostic accuracy in the differentiation of pre-operative cerebral gliomas when the tumor volume is derived from MET/PET images.

Effect of Accreditation on Accuracy of Diagnostic Tests in Medical Laboratories.

PubMed

Jang, Mi Ae; Yoon, Young Ahn; Song, Junghan; Kim, Jeong Ho; Min, Won Ki; Lee, Ji Sung; Lee, Yong Wha; Lee, You Kyoung

2017-05-01

Medical laboratories play a central role in health care. Many laboratories are taking a more focused and stringent approach to quality system management. In Korea, laboratory standardization efforts undertaken by the Korean Laboratory Accreditation Program (KLAP) and the Korean External Quality Assessment Scheme (KEQAS) may have facilitated an improvement in laboratory performance, but there are no fundamental studies demonstrating that laboratory standardization is effective. We analyzed the results of the KEQAS to identify significant differences between laboratories with or without KLAP and to determine the impact of laboratory standardization on the accuracy of diagnostic tests. We analyzed KEQAS participant data on clinical chemistry tests such as albumin, ALT, AST, and glucose from 2010 to 2013. As a statistical parameter to assess performance bias between laboratories, we compared 4-yr variance index score (VIS) between the two groups with or without KLAP. Compared with the group without KLAP, the group with KLAP exhibited significantly lower geometric means of 4-yr VIS for all clinical chemistry tests (P<0.0001); this difference justified a high level of confidence in standardized services provided by accredited laboratories. Confidence intervals for the mean of each test in the two groups (accredited and non-accredited) did not overlap, suggesting that the means of the groups are significantly different. These results confirmed that practice standardization is strongly associated with the accuracy of test results. Our study emphasizes the necessity of establishing a system for standardization of diagnostic testing. © The Korean Society for Laboratory Medicine

Stratified computed tomography findings improve diagnostic accuracy for appendicitis

PubMed Central

Park, Geon; Lee, Sang Chul; Choi, Byung-Jo; Kim, Say-June

2014-01-01

AIM: To improve the diagnostic accuracy in patients with symptoms and signs of appendicitis, but without confirmative computed tomography (CT) findings. METHODS: We retrospectively reviewed the database of 224 patients who had been operated on for the suspicion of appendicitis, but whose CT findings were negative or equivocal for appendicitis. The patient population was divided into two groups: a pathologically proven appendicitis group (n = 177) and a non-appendicitis group (n = 47). The CT images of these patients were re-evaluated according to the characteristic CT features as described in the literature. The re-evaluations and baseline characteristics of the two groups were compared. RESULTS: The two groups showed significant differences with respect to appendiceal diameter, and the presence of periappendiceal fat stranding and intraluminal air in the appendix. A larger proportion of patients in the appendicitis group showed distended appendices larger than 6.0 mm (66.3% vs 37.0%; P < 0.001), periappendiceal fat stranding (34.1% vs 8.9%; P = 0.001), and the absence of intraluminal air (67.6% vs 48.9%; P = 0.024) compared to the non-appendicitis group. Furthermore, the presence of two or more of these factors increased the odds ratio to 6.8 times higher than baseline (95%CI: 3.013-15.454; P < 0.001). CONCLUSION: Appendiceal diameter and wall thickening, fat stranding, and absence of intraluminal air can be used to increased diagnostic accuracy for appendicitis with equivocal CT findings. PMID:25320531

Effect of Accreditation on Accuracy of Diagnostic Tests in Medical Laboratories

PubMed Central

Jang, Mi-Ae; Yoon, Young Ahn; Song, Junghan; Kim, Jeong-Ho; Min, Won-Ki; Lee, Ji Sung

2017-01-01

Background Medical laboratories play a central role in health care. Many laboratories are taking a more focused and stringent approach to quality system management. In Korea, laboratory standardization efforts undertaken by the Korean Laboratory Accreditation Program (KLAP) and the Korean External Quality Assessment Scheme (KEQAS) may have facilitated an improvement in laboratory performance, but there are no fundamental studies demonstrating that laboratory standardization is effective. We analyzed the results of the KEQAS to identify significant differences between laboratories with or without KLAP and to determine the impact of laboratory standardization on the accuracy of diagnostic tests. Methods We analyzed KEQAS participant data on clinical chemistry tests such as albumin, ALT, AST, and glucose from 2010 to 2013. As a statistical parameter to assess performance bias between laboratories, we compared 4-yr variance index score (VIS) between the two groups with or without KLAP. Results Compared with the group without KLAP, the group with KLAP exhibited significantly lower geometric means of 4-yr VIS for all clinical chemistry tests (P<0.0001); this difference justified a high level of confidence in standardized services provided by accredited laboratories. Confidence intervals for the mean of each test in the two groups (accredited and non-accredited) did not overlap, suggesting that the means of the groups are significantly different. Conclusions These results confirmed that practice standardization is strongly associated with the accuracy of test results. Our study emphasizes the necessity of establishing a system for standardization of diagnostic testing. PMID:28224767

Systematic review of discharge coding accuracy

PubMed Central

Burns, E.M.; Rigby, E.; Mamidanna, R.; Bottle, A.; Aylin, P.; Ziprin, P.; Faiz, O.D.

2012-01-01

Introduction Routinely collected data sets are increasingly used for research, financial reimbursement and health service planning. High quality data are necessary for reliable analysis. This study aims to assess the published accuracy of routinely collected data sets in Great Britain. Methods Systematic searches of the EMBASE, PUBMED, OVID and Cochrane databases were performed from 1989 to present using defined search terms. Included studies were those that compared routinely collected data sets with case or operative note review and those that compared routinely collected data with clinical registries. Results Thirty-two studies were included. Twenty-five studies compared routinely collected data with case or operation notes. Seven studies compared routinely collected data with clinical registries. The overall median accuracy (routinely collected data sets versus case notes) was 83.2% (IQR: 67.3–92.1%). The median diagnostic accuracy was 80.3% (IQR: 63.3–94.1%) with a median procedure accuracy of 84.2% (IQR: 68.7–88.7%). There was considerable variation in accuracy rates between studies (50.5–97.8%). Since the 2002 introduction of Payment by Results, accuracy has improved in some respects, for example primary diagnoses accuracy has improved from 73.8% (IQR: 59.3–92.1%) to 96.0% (IQR: 89.3–96.3), P= 0.020. Conclusion Accuracy rates are improving. Current levels of reported accuracy suggest that routinely collected data are sufficiently robust to support their use for research and managerial decision-making. PMID:21795302

Which cuff should I use? Indirect blood pressure measurement for the diagnosis of hypertension in patients with obesity: a diagnostic accuracy review.

PubMed

Irving, Greg; Holden, John; Stevens, Richard; McManus, Richard J

2016-11-03

To determine the diagnostic accuracy of different methods of blood pressure (BP) measurement compared with reference standards for the diagnosis of hypertension in patients with obesity with a large arm circumference. Systematic review with meta-analysis with hierarchical summary receiver operating characteristic models. Bland-Altman analyses where individual patient data were available. Methodological quality appraised using Quality Assessment of Diagnostic Accuracy Studies 2 (QUADAS2) criteria. MEDLINE, EMBASE, Cochrane, DARE, Medion and Trip databases were searched. Cross-sectional, randomised and cohort studies of diagnostic test accuracy that compared any non-invasive BP tests (upper arm, forearm, wrist, finger) with an appropriate reference standard (invasive BP, correctly fitting upper arm cuff, ambulatory BP monitoring) in primary care were included. 4037 potentially relevant papers were identified. 20 studies involving 26 different comparisons met the inclusion criteria. Individual patient data were available from 4 studies. No studies satisfied all QUADAS2 criteria. Compared with the reference test of invasive BP, a correctly fitting upper arm BP cuff had a sensitivity of 0.87 (0.79 to 0.93) and a specificity of 0.85 (0.64 to 0.95); insufficient evidence was available for other comparisons to invasive BP. Compared with the reference test of a correctly fitting upper arm cuff, BP measurement at the wrist had a sensitivity of 0.92 (0.64 to 0.99) and a specificity of 0.92 (0.85 to 0.87). Measurement with an incorrectly fitting standard cuff had a sensitivity of 0.73 (0.67 to 0.78) and a specificity of 0.76 (0.69 to 0.82). Measurement at the forearm had a sensitivity of 0.84 (0.71 to 0.92) and a specificity 0.75 of (0.66 to 0.83). Bland-Altman analysis of individual patient data from 3 studies comparing wrist and upper arm BP showed a mean difference of 0.46 mm Hg for systolic BP measurement and 2.2 mm Hg for diastolic BP measurement. BP measurement with a correctly fitting upper arm cuff is sufficiently sensitive and specific to diagnose hypertension in patients with obesity with a large upper arm circumference. If a correctly fitting upper arm cuff cannot be applied, an incorrectly fitting standard size cuff should not be used and BP measurement at the wrist should be considered. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

Which cuff should I use? Indirect blood pressure measurement for the diagnosis of hypertension in patients with obesity: a diagnostic accuracy review

PubMed Central

Holden, John

2016-01-01

Objective To determine the diagnostic accuracy of different methods of blood pressure (BP) measurement compared with reference standards for the diagnosis of hypertension in patients with obesity with a large arm circumference. Design Systematic review with meta-analysis with hierarchical summary receiver operating characteristic models. Bland-Altman analyses where individual patient data were available. Methodological quality appraised using Quality Assessment of Diagnostic Accuracy Studies 2 (QUADAS2) criteria. Data sources MEDLINE, EMBASE, Cochrane, DARE, Medion and Trip databases were searched. Eligibility criteria Cross-sectional, randomised and cohort studies of diagnostic test accuracy that compared any non-invasive BP tests (upper arm, forearm, wrist, finger) with an appropriate reference standard (invasive BP, correctly fitting upper arm cuff, ambulatory BP monitoring) in primary care were included. Results 4037 potentially relevant papers were identified. 20 studies involving 26 different comparisons met the inclusion criteria. Individual patient data were available from 4 studies. No studies satisfied all QUADAS2 criteria. Compared with the reference test of invasive BP, a correctly fitting upper arm BP cuff had a sensitivity of 0.87 (0.79 to 0.93) and a specificity of 0.85 (0.64 to 0.95); insufficient evidence was available for other comparisons to invasive BP. Compared with the reference test of a correctly fitting upper arm cuff, BP measurement at the wrist had a sensitivity of 0.92 (0.64 to 0.99) and a specificity of 0.92 (0.85 to 0.87). Measurement with an incorrectly fitting standard cuff had a sensitivity of 0.73 (0.67 to 0.78) and a specificity of 0.76 (0.69 to 0.82). Measurement at the forearm had a sensitivity of 0.84 (0.71 to 0.92) and a specificity 0.75 of (0.66 to 0.83). Bland-Altman analysis of individual patient data from 3 studies comparing wrist and upper arm BP showed a mean difference of 0.46 mm Hg for systolic BP measurement and 2.2 mm Hg for diastolic BP measurement. Conclusions BP measurement with a correctly fitting upper arm cuff is sufficiently sensitive and specific to diagnose hypertension in patients with obesity with a large upper arm circumference. If a correctly fitting upper arm cuff cannot be applied, an incorrectly fitting standard size cuff should not be used and BP measurement at the wrist should be considered. PMID:27810973

Cytology-based treatment decision in primary lung cancer: is it accurate enough?

PubMed

Sakr, Lama; Roll, Patrice; Payan, Marie-José; Liprandi, Agnès; Dutau, Hervé; Astoul, Philippe; Robaglia-Schlupp, Andrée; Loundou, Anderson; Barlesi, Fabrice

2012-03-01

Accurate distinction of lung cancer types has become increasingly important as recent trials have shown differential response to chemotherapy among non-small cell lung carcinoma (NSCLC) subtypes. Cytological procedures are frequently used but their diagnostic accuracy has been previously questioned. However, new endoscopic and cytological techniques might have improved cytological accuracy in comparison with prior findings. The aim of this study was to reassess cytological accuracy for diagnosis of lung cancer subtypes. A retrospective chart review of subjects who underwent fiberoptic bronchoscopy (FOB) for suspicion of lung cancer in 2007-2008, was undertaken. Reports of bronchoscopically derived cytological specimens were compared to those of histological material. Endoscopic findings and specific investigational techniques were taken into account. A total of 467 FOB with both cytological and histological diagnostic techniques were performed in 449 subjects. Patients consisted of 345 men and 104 women (median age, 65 yrs). Cytology proved malignancy in 157 patients. Cytologically diagnosed carcinomas were classified into squamous cell carcinoma (SqCC) in 56, adenocarcinoma (ADC) in 6, small cell lung carcinoma (SCLC) in 12, non-small cell lung carcinoma not otherwise specified (NSCLC-NOS) in 71, and unclassified carcinoma in 12. Cytology correlated fairly with biopsy specimens, as agreement was observed in 83% of SCLC, 100% of ADC, 74% of SqCC and 8% of NSCLC-NOS. Interestingly, 61% of cytologically identified NSCLC-NOS were classified as ADC by histology. Cytological accuracy improved in case of an endobronchial lesion, mainly for SqCC. These results indicate that cytological accuracy remains fair with regard to diagnosis of squamous and non-squamous lung cancer subtypes. Improvement of cytological accuracy is expected however with novel diagnostic strategies. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

Radiation injury vs. recurrent brain metastasis: combining textural feature radiomics analysis and standard parameters may increase 18F-FET PET accuracy without dynamic scans.

PubMed

Lohmann, Philipp; Stoffels, Gabriele; Ceccon, Garry; Rapp, Marion; Sabel, Michael; Filss, Christian P; Kamp, Marcel A; Stegmayr, Carina; Neumaier, Bernd; Shah, Nadim J; Langen, Karl-Josef; Galldiks, Norbert

2017-07-01

We investigated the potential of textural feature analysis of O-(2-[ 18 F]fluoroethyl)-L-tyrosine ( 18 F-FET) PET to differentiate radiation injury from brain metastasis recurrence. Forty-seven patients with contrast-enhancing brain lesions (n = 54) on MRI after radiotherapy of brain metastases underwent dynamic 18 F-FET PET. Tumour-to-brain ratios (TBRs) of 18 F-FET uptake and 62 textural parameters were determined on summed images 20-40 min post-injection. Tracer uptake kinetics, i.e., time-to-peak (TTP) and patterns of time-activity curves (TAC) were evaluated on dynamic PET data from 0-50 min post-injection. Diagnostic accuracy of investigated parameters and combinations thereof to discriminate between brain metastasis recurrence and radiation injury was compared. Diagnostic accuracy increased from 81 % for TBR mean alone to 85 % when combined with the textural parameter Coarseness or Short-zone emphasis. The accuracy of TBR max alone was 83 % and increased to 85 % after combination with the textural parameters Coarseness, Short-zone emphasis, or Correlation. Analysis of TACs resulted in an accuracy of 70 % for kinetic pattern alone and increased to 83 % when combined with TBR max . Textural feature analysis in combination with TBRs may have the potential to increase diagnostic accuracy for discrimination between brain metastasis recurrence and radiation injury, without the need for dynamic 18 F-FET PET scans. • Textural feature analysis provides quantitative information about tumour heterogeneity • Textural features help improve discrimination between brain metastasis recurrence and radiation injury • Textural features might be helpful to further understand tumour heterogeneity • Analysis does not require a more time consuming dynamic PET acquisition.

Diagnostic accuracy of fractional exhaled nitric oxide measurement in predicting cough-variant asthma and eosinophilic bronchitis in adults with chronic cough: A systematic review and meta-analysis.

PubMed

Song, Woo-Jung; Kim, Hyun Jung; Shim, Ji-Su; Won, Ha-Kyeong; Kang, Sung-Yoon; Sohn, Kyoung-Hee; Kim, Byung-Keun; Jo, Eun-Jung; Kim, Min-Hye; Kim, Sang-Heon; Park, Heung-Woo; Kim, Sun-Sin; Chang, Yoon-Seok; Morice, Alyn H; Lee, Byung-Jae; Cho, Sang-Heon

2017-09-01

Individual studies have suggested the utility of fractional exhaled nitric oxide (Feno) measurement in detecting cough-variant asthma (CVA) and eosinophilic bronchitis (EB) in patients with chronic cough. We sought to obtain summary estimates of diagnostic test accuracy of Feno measurement in predicting CVA, EB, or both in adults with chronic cough. Electronic databases were searched for studies published until January 2016, without language restriction. Cross-sectional studies that reported the diagnostic accuracy of Feno measurement for detecting CVA or EB were included. Risk of bias was assessed with Quality Assessment of Diagnostic Accuracy Studies 2. Random effects meta-analyses were performed to obtain summary estimates of the diagnostic accuracy of Feno measurement. A total of 15 studies involving 2187 adults with chronic cough were identified. Feno measurement had a moderate diagnostic accuracy in predicting CVA in patients with chronic cough, showing the summary area under the curve to be 0.87 (95% CI, 0.83-0.89). Specificity was higher and more consistent than sensitivity (0.85 [95% CI, 0.81-0.88] and 0.72 [95% CI, 0.61-0.81], respectively). However, in the nonasthmatic population with chronic cough, the diagnostic accuracy to predict EB was found to be relatively lower (summary area under the curve, 0.81 [95% CI, 0.77-0.84]), and specificity was inconsistent. The present meta-analyses indicated the diagnostic potential of Feno measurement as a rule-in test for detecting CVA in adult patients with chronic cough. However, Feno measurement may not be useful to predict EB in nonasthmatic subjects with chronic cough. These findings warrant further studies to validate the roles of Feno measurement in clinical practice of patients with chronic cough. Copyright © 2017 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

Accuracy of an Immunochromatographic Diagnostic Test (ICT Malaria Combo Cassette Test) Compared to Microscopy among under Five-Year-Old Children when Diagnosing Malaria in Equatorial Guinea

PubMed Central

Portero, José-Luis; Rubio-Yuste, Maria; Descalzo, Miguel Angel; Raso, Jose; Lwanga, Magdalena; Obono, Jaquelina; Nseng, Gloria; Benito, Agustin; Cano, Jorge

2010-01-01

Conventional malaria diagnosis based on microscopy raises serious difficulties in weak health systems. Cost-effective and sensitive rapid diagnostic tests have been recently proposed as alternatives to microscopy. In Equatorial Guinea, a study was conducted to assess the reliability of a rapid diagnostic test compared to microscopy. The study was designed in accordance with the directives of the Standards for Reporting Diagnostic Accuracy Initiative (STARD). Peripheral thick and thin films for the microscopy diagnosis and a rapid immunochromatographic test (ICT Malaria Combo Cassette Test) were performed on under five-year-old children with malaria suspicion. The ICT test detected Plasmodium spp. infection with a sensitivity of 81.5% and a specificity of 81.9% while P. falciparum diagnosis occurred with a sensitivity of 69.7% and a specificity of 73.7%. The sensitivity of the ICT test increased with higher parasitemias. The general results showed little concordance between the ICT test and microscopy (kappa = 0.28, se: 0.04). In Equatorial Guinea, the ICT Malaria Combo Cassette Test has proven to be an acceptable test to detect high P. falciparum parasitemias. However, the decrease of sensitivity at medium and low parasitemias hampers that ICT can replace properly performed microscopy at present in the diagnosis of malaria in children. PMID:22332024

Does clinical pretest probability influence image quality and diagnostic accuracy in dual-source coronary CT angiography?

PubMed

Thomas, Christoph; Brodoefel, Harald; Tsiflikas, Ilias; Bruckner, Friederike; Reimann, Anja; Ketelsen, Dominik; Drosch, Tanja; Claussen, Claus D; Kopp, Andreas; Heuschmid, Martin; Burgstahler, Christof

2010-02-01

To prospectively evaluate the influence of the clinical pretest probability assessed by the Morise score onto image quality and diagnostic accuracy in coronary dual-source computed tomography angiography (DSCTA). In 61 patients, DSCTA and invasive coronary angiography were performed. Subjective image quality and accuracy for stenosis detection (>50%) of DSCTA with invasive coronary angiography as gold standard were evaluated. The influence of pretest probability onto image quality and accuracy was assessed by logistic regression and chi-square testing. Correlations of image quality and accuracy with the Morise score were determined using linear regression. Thirty-eight patients were categorized into the high, 21 into the intermediate, and 2 into the low probability group. Accuracies for the detection of significant stenoses were 0.94, 0.97, and 1.00, respectively. Logistic regressions and chi-square tests showed statistically significant correlations between Morise score and image quality (P < .0001 and P < .001) and accuracy (P = .0049 and P = .027). Linear regression revealed a cutoff Morise score for a good image quality of 16 and a cutoff for a barely diagnostic image quality beyond the upper Morise scale. Pretest probability is a weak predictor of image quality and diagnostic accuracy in coronary DSCTA. A sufficient image quality for diagnostic images can be reached with all pretest probabilities. Therefore, coronary DSCTA might be suitable also for patients with a high pretest probability. Copyright 2010 AUR. Published by Elsevier Inc. All rights reserved.

Accuracy of Referring Provider and Endoscopist Impressions of Colonoscopy Indication.

PubMed

Naveed, Mariam; Clary, Meredith; Ahn, Chul; Kubiliun, Nisa; Agrawal, Deepak; Cryer, Byron; Murphy, Caitlin; Singal, Amit G

2017-07-01

Background: Referring provider and endoscopist impressions of colonoscopy indication are used for clinical care, reimbursement, and quality reporting decisions; however, the accuracy of these impressions is unknown. This study assessed the sensitivity, specificity, positive and negative predictive value, and overall accuracy of methods to classify colonoscopy indication, including referring provider impression, endoscopist impression, and administrative algorithm compared with gold standard chart review. Methods: We randomly sampled 400 patients undergoing a colonoscopy at a Veterans Affairs health system between January 2010 and December 2010. Referring provider and endoscopist impressions of colonoscopy indication were compared with gold-standard chart review. Indications were classified into 4 mutually exclusive categories: diagnostic, surveillance, high-risk screening, or average-risk screening. Results: Of 400 colonoscopies, 26% were performed for average-risk screening, 7% for high-risk screening, 26% for surveillance, and 41% for diagnostic indications. Accuracy of referring provider and endoscopist impressions of colonoscopy indication were 87% and 84%, respectively, which were significantly higher than that of the administrative algorithm (45%; P <.001 for both). There was substantial agreement between endoscopist and referring provider impressions (κ=0.76). All 3 methods showed high sensitivity (>90%) for determining screening (vs nonscreening) indication, but specificity of the administrative algorithm was lower (40.3%) compared with referring provider (93.7%) and endoscopist (84.0%) impressions. Accuracy of endoscopist, but not referring provider, impression was lower in patients with a family history of colon cancer than in those without (65% vs 84%; P =.001). Conclusions: Referring provider and endoscopist impressions of colonoscopy indication are both accurate and may be useful data to incorporate into algorithms classifying colonoscopy indication. Copyright © 2017 by the National Comprehensive Cancer Network.

Evaluation of pCLE in the bile duct: final results of EMID study : pCLE: impact in the management of bile duct strictures.

PubMed

Caillol, Fabrice; Bories, Erwan; Autret, Aurelie; Poizat, Flora; Pesenti, Christian; Ewald, Jacques; Turrini, Olivier; Delpero, Jean Robert; Monges, Genevieve; Giovannini, Marc

2015-09-01

Pre-operative histology of bile duct stenosis is associated with low accuracy. Probe confocal laser endomicroscopy (pCLE) enables optical biopsy or in vivo histology. The definitive results of the EMID study are presented here, comparing optical biopsies with definitive histology. Sixty one patients with a biliary stricture without any previous histology were included (July 2007-May 2012). An endoscopic ultrasound (EUS) had to be conducted before the ERCP procedure. pCLE was done using CholangioFlex during the ERCP procedure. Results were compared to those of definitive histology obtained by biopsy or surgery in case of malignant lesions, and by surgery or 1-year follow-up in case of benign lesions. Six patients were excluded because no definitive histology was available. There were 41 malignant lesions and 14 benign lesions. Sensitivity, specificity, PPV, NPV, and accuracy with combination of pCLE with endobiliary and EUS biopsies were 100, 71, 91, 100, and 93%, respectively (with a significant increase of accuracy compared with endobiliary and EUS biopsies without pCLE, p = 0.03). 19 patients had a biliary stricture without individualized mass (6 malignant lesions, 13 benign lesions). Sensitivity, specificity, PPV, NPV, and accuracy for pCLE were 83, 77, 62, 91, and 79%, respectively. Sensitivity, specificity, PPV, NPV, and accuracy for combination of pCLE with endobiliary and EUS biopsies were 100, 69, 60, 100, and 79%, respectively. The addition of a pCLE procedure in the diagnostic histologic examination of a biliary stricture permits a significant increase in diagnostic reliability and allows for a VPN of 100%.

Proposed Diagnostic Criteria for Smartphone Addiction

PubMed Central

Lin, Yu-Hsuan; Chiang, Chih-Lin; Lin, Po-Hsien; Chang, Li-Ren; Ko, Chih-Hung; Lee, Yang-Han

2016-01-01

Background Global smartphone penetration has led to unprecedented addictive behaviors. The aims of this study are to develop diagnostic criteria of smartphone addiction and to examine the discriminative ability and the validity of the diagnostic criteria. Methods We developed twelve candidate criteria for characteristic symptoms of smartphone addiction and four criteria for functional impairment caused by excessive smartphone use. The participants consisted of 281 college students. Each participant was systematically assessed for smartphone-using behaviors by psychiatrist’s structured diagnostic interview. The sensitivity, specificity, and diagnostic accuracy of the candidate symptom criteria were analyzed with reference to the psychiatrists’ clinical global impression. The optimal model selection with its cutoff point of the diagnostic criteria differentiating the smartphone addicted subjects from non-addicted subjects was then determined by the best diagnostic accuracy. Results Six symptom criteria model with optimal cutoff point were determined based on the maximal diagnostic accuracy. The proposed smartphone addiction diagnostic criteria consisted of (1) six symptom criteria, (2) four functional impairment criteria and (3) exclusion criteria. Setting three symptom criteria as the cutoff point resulted in the highest diagnostic accuracy (84.3%), while the sensitivity and specificity were 79.4% and 87.5%, respectively. We suggested determining the functional impairment by two or more of the four domains considering the high accessibility and penetration of smartphone use. Conclusion The diagnostic criteria of smartphone addiction demonstrated the core symptoms “impaired control” paralleled with substance related and addictive disorders. The functional impairment involved multiple domains provide a strict standard for clinical assessment. PMID:27846211

Proposed Diagnostic Criteria for Smartphone Addiction.

PubMed

Lin, Yu-Hsuan; Chiang, Chih-Lin; Lin, Po-Hsien; Chang, Li-Ren; Ko, Chih-Hung; Lee, Yang-Han; Lin, Sheng-Hsuan

2016-01-01

Global smartphone penetration has led to unprecedented addictive behaviors. The aims of this study are to develop diagnostic criteria of smartphone addiction and to examine the discriminative ability and the validity of the diagnostic criteria. We developed twelve candidate criteria for characteristic symptoms of smartphone addiction and four criteria for functional impairment caused by excessive smartphone use. The participants consisted of 281 college students. Each participant was systematically assessed for smartphone-using behaviors by psychiatrist's structured diagnostic interview. The sensitivity, specificity, and diagnostic accuracy of the candidate symptom criteria were analyzed with reference to the psychiatrists' clinical global impression. The optimal model selection with its cutoff point of the diagnostic criteria differentiating the smartphone addicted subjects from non-addicted subjects was then determined by the best diagnostic accuracy. Six symptom criteria model with optimal cutoff point were determined based on the maximal diagnostic accuracy. The proposed smartphone addiction diagnostic criteria consisted of (1) six symptom criteria, (2) four functional impairment criteria and (3) exclusion criteria. Setting three symptom criteria as the cutoff point resulted in the highest diagnostic accuracy (84.3%), while the sensitivity and specificity were 79.4% and 87.5%, respectively. We suggested determining the functional impairment by two or more of the four domains considering the high accessibility and penetration of smartphone use. The diagnostic criteria of smartphone addiction demonstrated the core symptoms "impaired control" paralleled with substance related and addictive disorders. The functional impairment involved multiple domains provide a strict standard for clinical assessment.

Use of 3×2 tables with an intention to diagnose approach to assess clinical performance of diagnostic tests: meta-analytical evaluation of coronary CT angiography studies

PubMed Central

Schuetz, Georg M; Schlattmann, Peter

2012-01-01

Objective To determine whether a 3×2 table, using an intention to diagnose approach, is better than the “classic” 2×2 table at handling transparent reporting and non-evaluable results, when assessing the accuracy of a diagnostic test. Design Based on a systematic search for diagnostic accuracy studies of coronary computed tomography (CT) angiography, full texts of relevant studies were evaluated to determine whether they could calculate an alternative 3×2 table. To quantify an overall effect, we pooled diagnostic accuracy values according to a meta-analytical approach. Data sources Medline (via PubMed), Embase (via Ovid), and ISI Web of Science electronic databases. Eligibility criteria Prospective English or German language studies comparing coronary CT with conventional coronary angiography in all patients and providing sufficient data for a patient level analysis. Results 120 studies (10 287 patients) were eligible. Studies varied greatly in their approaches to handling non-evaluable findings. We found 26 studies (including 2298 patients) that allowed us to calculate both 2×2 tables and 3×2 tables. Using a bivariate random effects model, we compared the 2×2 table with the 3×2 table, and found significant differences for pooled sensitivity (98.2 (95% confidence interval 96.7 to 99.1) v 92.7 (88.5 to 95.3)), area under the curve (0.99 (0.98 to 1.00) v 0.93 (0.91 to 0.95)), positive likelihood ratio (9.1 (6.2 to 13.3) v 4.4 (3.3 to 6.0)), and negative likelihood ratio (0.02 (0.01 to 0.04) v 0.09 (0.06 to 0.15); (P<0.05)). Conclusion Parameters for diagnostic performance significantly decrease if non-evaluable results are included by a 3×2 table for analysis (intention to diagnose approach). This approach provides a more realistic picture of the clinical potential of diagnostic tests. PMID:23097549

Comparative evaluation of Indian Diabetes Risk Score and Finnish Diabetes Risk Score for predicting risk of diabetes mellitus type II: A teaching hospital-based survey in Maharashtra.

PubMed

Pawar, Shivshakti D; Naik, Jayashri D; Prabhu, Priya; Jatti, Gajanan M; Jadhav, Sachin B; Radhe, B K

2017-01-01

India is currently becoming capital for diabetes mellitus. This significantly increasing incidence of diabetes putting an additional burden on health care in India. Unfortunately, half of diabetic individuals are unknown about their diabetic status. Hence, there is an emergent need of effective screening instrument to identify "diabetes risk" individuals. The aim is to evaluate and compare the diagnostic accuracy and clinical utility of Indian Diabetes Risk Score (IDRS) and Finnish Diabetes Risk Score (FINDRISC). This is retrospective, record-based study of diabetes detection camp organized by a teaching hospital. Out of 780 people attended this camp voluntarily only 763 fulfilled inclusion criteria of the study. In this camp, pro forma included the World Health Organization STEP guidelines for surveillance of noncommunicable diseases. Included primary sociodemographic characters, physical measurements, and clinical examination. After that followed the random blood glucose estimation of each individual. Diagnostic accuracy of IDRS and FINDRISC compared by using receiver operative characteristic curve (ROC). Sensitivity, specificity, likelihood ratio, positive predictive and negative predictive values were compared. Clinical utility index (CUI) of each score also compared. SPSS version 22, Stata 13, R3.2.9 used. Out of 763 individuals, 38 were new diabetics. By IDRS 347 and by FINDRISC 96 people were included in high-risk category for diabetes. Odds ratio for high-risk people in FINDRISC for getting affected by diabetes was 10.70. Similarly, it was 4.79 for IDRS. Area under curves of ROCs of both scores were indifferent ( P = 0.98). Sensitivity and specificity of IDRS was 78.95% and 56.14%; whereas for FINDRISC it was 55.26% and 89.66%, respectively. CUI was excellent (0.86) for FINDRISC while IDRS it was "satisfactory" (0.54). Bland-Altman plot and Cohen's Kappa suggested fair agreement between these score in measuring diabetes risk. Diagnostic accuracy and clinical utility of FINDRISC is fairly good than IDRS.

Interobserver Variability and Accuracy of High-Definition Endoscopic Diagnosis for Gastric Intestinal Metaplasia among Experienced and Inexperienced Endoscopists

PubMed Central

Hyun, Yil Sik; Bae, Joong Ho; Park, Hye Sun; Eun, Chang Soo

2013-01-01

Accurate diagnosis of gastric intestinal metaplasia is important; however, conventional endoscopy is known to be an unreliable modality for diagnosing gastric intestinal metaplasia (IM). The aims of the study were to evaluate the interobserver variation in diagnosing IM by high-definition (HD) endoscopy and the diagnostic accuracy of this modality for IM among experienced and inexperienced endoscopists. Selected 50 cases, taken with HD endoscopy, were sent for a diagnostic inquiry of gastric IM through visual inspection to five experienced and five inexperienced endoscopists. The interobserver agreement between endoscopists was evaluated to verify the diagnostic reliability of HD endoscopy in diagnosing IM, and the diagnostic accuracy, sensitivity, and specificity were evaluated for validity of HD endoscopy in diagnosing IM. Interobserver agreement among the experienced endoscopists was "poor" (κ = 0.38) and it was also "poor" (κ = 0.33) among the inexperienced endoscopists. The diagnostic accuracy of the experienced endoscopists was superior to that of the inexperienced endoscopists (P = 0.003). Since diagnosis through visual inspection is unreliable in the diagnosis of IM, all suspicious areas for gastric IM should be considered to be biopsied. Furthermore, endoscopic experience and education are needed to raise the diagnostic accuracy of gastric IM. PMID:23678267

Interobserver variability and accuracy of high-definition endoscopic diagnosis for gastric intestinal metaplasia among experienced and inexperienced endoscopists.

PubMed

Hyun, Yil Sik; Han, Dong Soo; Bae, Joong Ho; Park, Hye Sun; Eun, Chang Soo

2013-05-01

Accurate diagnosis of gastric intestinal metaplasia is important; however, conventional endoscopy is known to be an unreliable modality for diagnosing gastric intestinal metaplasia (IM). The aims of the study were to evaluate the interobserver variation in diagnosing IM by high-definition (HD) endoscopy and the diagnostic accuracy of this modality for IM among experienced and inexperienced endoscopists. Selected 50 cases, taken with HD endoscopy, were sent for a diagnostic inquiry of gastric IM through visual inspection to five experienced and five inexperienced endoscopists. The interobserver agreement between endoscopists was evaluated to verify the diagnostic reliability of HD endoscopy in diagnosing IM, and the diagnostic accuracy, sensitivity, and specificity were evaluated for validity of HD endoscopy in diagnosing IM. Interobserver agreement among the experienced endoscopists was "poor" (κ = 0.38) and it was also "poor" (κ = 0.33) among the inexperienced endoscopists. The diagnostic accuracy of the experienced endoscopists was superior to that of the inexperienced endoscopists (P = 0.003). Since diagnosis through visual inspection is unreliable in the diagnosis of IM, all suspicious areas for gastric IM should be considered to be biopsied. Furthermore, endoscopic experience and education are needed to raise the diagnostic accuracy of gastric IM.

Application of magnetic resonance imaging in diagnosis of Uterus Cervical Carcinoma.

PubMed

Peng, Jidong; Wang, Weiqiang; Zeng, Daohui

2017-01-01

Effective treatment of Uterus Cervical Carcinoma (UCC) rely heavily on the precise pre-surgical staging. The conventional International Federation of Gynecology and Obstetrics (FIGO) system based on clinical examination is being applied worldwide for UCC staging. Yet its performance just appears passable. Thus, this study aims to investigate the value of applying Magnetic Resonance Imaging (MRI) with clinical examination in staging of UCC. A retrospective dataset involving 164 patients diagnosed with UCC was enrolled in this study. The mean age of this study population was 46.1 years (range, 28-#x2013;75 years). All patients underwent operations and UCC types were confirmed by pathological examinations. The tumor stages were determined by two experienced Gynecologist independently based on FIGO examinations and MRI. The diagnostic results were also compared with the post-operative pathologic reports. Statistical data analysis on diagnostic performance was then done and reported. The study results showed that the overall accuracy of applying MRI in UCC staging was 82.32%, while using FIGO staging method, the staging accuracy was 59.15%. MRI is suitable to evaluate tumor extent with high accuracy, and it can offer more objective information for the diagnosis and staging of UCC. Compared with clinical examinations based on FIGO, MRI illustrated relatively high accuracy in evaluating UCC staging, and is worthwhile to be recommended in future clinical practice.

Utility of non-rule-based visual matching as a strategy to allow novices to achieve skin lesion diagnosis.

PubMed

Aldridge, R Benjamin; Glodzik, Dominik; Ballerini, Lucia; Fisher, Robert B; Rees, Jonathan L

2011-05-01

Non-analytical reasoning is thought to play a key role in dermatology diagnosis. Considering its potential importance, surprisingly little work has been done to research whether similar identification processes can be supported in non-experts. We describe here a prototype diagnostic support software, which we have used to examine the ability of medical students (at the beginning and end of a dermatology attachment) and lay volunteers, to diagnose 12 images of common skin lesions. Overall, the non-experts using the software had a diagnostic accuracy of 98% (923/936) compared with 33% for the control group (215/648) (Wilcoxon p < 0.0001). We have demonstrated, within the constraints of a simplified clinical model, that novices' diagnostic scores are significantly increased by the use of a structured image database coupled with matching of index and referent images. The novices achieve this high degree of accuracy without any use of explicit definitions of likeness or rule-based strategies.

Hippocampus and Basal Forebrain Volumetry for Dementia and Mild Cognitive Impairment Diagnosis: Could It Be Useful in Primary Care?

PubMed

Teipel, Stefan J; Keller, Felix; Thyrian, Jochen R; Strohmaier, Urs; Altiner, Attila; Hoffmann, Wolfgang; Kilimann, Ingo

2017-01-01

Once a patient or a knowledgeable informant has noticed decline in memory or other cognitive functions, initiation of early dementia assessment is recommended. Hippocampus and cholinergic basal forebrain (BF) volumetry supports the detection of prodromal and early stages of Alzheimer's disease (AD) dementia in highly selected patient populations. To compare effect size and diagnostic accuracy of hippocampus and BF volumetry between patients recruited in highly specialized versus primary care and to assess the effect of white matter lesions as a proxy for cerebrovascular comorbidity on diagnostic accuracy. We determined hippocampus and BF volumes and white matter lesion load from MRI scans of 71 participants included in a primary care intervention trial (clinicaltrials.gov identifier: NCT01401582) and matched 71 participants stemming from a memory clinic. Samples included healthy controls and people with mild cognitive impairment (MCI), AD dementia, mixed dementia, and non-AD related dementias. Volumetric measures reached similar effect sizes and cross-validated levels of accuracy in the primary care and the memory clinic samples for the discrimination of AD and mixed dementia cases from healthy controls. In the primary care MCI cases, volumetric measures reached only random guessing levels of accuracy. White matter lesions had only a modest effect on effect size and diagnostic accuracy. Hippocampus and BF volumetry may usefully be employed for the identification of AD and mixed dementia, but the detection of MCI does not benefit from the use of these volumetric markers in a primary care setting.

Ultrathin endoscopy versus high-resolution endoscopy for diagnosing superficial gastric neoplasia.

PubMed

Toyoizumi, Hirobumi; Kaise, Mitsuru; Arakawa, Hiroshi; Yonezawa, Jin; Yoshida, Yukinaga; Kato, Masayuki; Yoshimura, Noboru; Goda, Ken-ichi; Tajiri, Hisao

2009-08-01

Ultrathin endoscopy (UTE) is an acceptable and cost-effective alternative to EGD with the patient under sedation, although the diagnostic accuracy of UTE is not well established. To compare the diagnostic accuracy of UTE and high-resolution endoscopy (HRE) for superficial gastric neoplasia. Prospective comparative study. Academic center. Patients with or without superficial gastric neoplasia underwent peroral UTE and HRE, back-to-back in a random order while under standard sedation. The procedures were performed by 2 endoscopists who were blinded to the clinical information. The rate of missed lesions and misdiagnosis, sensitivity, and specificity for the diagnosis of gastric neoplasia when using pathology as the reference standard. In total, 126 lesions (41 superficial gastric neoplasias, 85 nonneoplastic lesions) were recorded in 57 enrolled patients. For the diagnosis of gastric neoplasia, the sensitivity of UTE (58.5%) was significantly (P = .021) lower than that of HRE (78%), and the specificity of UTE (91.8%) was significantly (P = .014) lower than that of HRE (100%). The rate of missed lesions and misdiagnosis of gastric neoplasias when using UTE (41.5%) was significantly (P > .001) higher than that of HRE (22.0%). The corresponding rate of neoplasias at the proximal portion (fornix and corpus) when using UTE (29%) was significantly (P = .002) higher than that of HRE (7.2%), although the rates of neoplasias at the distal portion (angulus and antrum) were comparable for UTE and HRE. Small sample numbers in an enriched population. The diagnostic accuracy of UTE is significantly lower than that of HRE for superficial gastric neoplasia, and this difference is particularly striking for neoplasias in the proximal stomach. For UTE to be used as an alternative modality, improvements in optical quality and the incorporation of additional procedures, including close-range observations and chromoendoscopy, are required to enhance visualization.

Diagnostic accuracy and reproducibility of the Ottawa Knee Rule vs the Pittsburgh Decision Rule.

PubMed

Cheung, Tung C; Tank, Yeliz; Breederveld, Roelf S; Tuinebreijer, Wim E; de Lange-de Klerk, Elly S M; Derksen, Robert J

2013-04-01

The aim of this present study was to compare the diagnostic accuracy and reproducibility of 2 clinical decision rules (the Ottawa Knee Rules [OKR] and Pittsburgh Decision Rules [PDR]) developed for selective use of x-rays in the evaluation of isolated knee trauma. Application of a decision rule leads to a more efficient evaluation of knee injuries and a reduction in health care costs. The diagnostic accuracy and reproducibility are compared in this study. A cross-sectional interobserver study was conducted in the emergency department of an urban teaching hospital from October 2008 to July 2009. Two observer groups collected data on standardized case-report forms: emergency medicine residents and surgical residents. Standard knee radiographs were performed in each patient. Participants were patients 18 years and older with isolated knee injuries. Pooled sensitivity and specificity were compared using χ(2) statistics, and interobserver agreement was calculated by using κ statistics. Ninety injuries were assessed. Seven injuries concerned fractures (7.8%). For the OKR, the pooled sensitivity and specificity were 0.86 (95% confidence interval [CI], 0.57-0.96) and 0.27 (95% CI, 0.21-0.35), respectively. The PDR had a pooled sensitivity and specificity of 0.86 (95% CI, 0.57-0.96) and 0.51 (95% CI, 0.44-0.59). The PDR was significantly (P = .002) more specific. The κ values for the OKR and PDR were 0.51 (95% CI, 0.32-0.71) and 0.71 (95% CI, 0.57-0.86), respectively. The PDR was found to be more specific than the OKR, with equal sensitivity. Interobserver agreement was moderate for the OKR and substantial for the PDR. Copyright © 2013 Elsevier Inc. All rights reserved.

The diagnostic accuracy of multiparametric MRI to determine pediatric brain tumor grades and types.

PubMed

Koob, Mériam; Girard, Nadine; Ghattas, Badih; Fellah, Slim; Confort-Gouny, Sylviane; Figarella-Branger, Dominique; Scavarda, Didier

2016-04-01

Childhood brain tumors show great histological variability. The goal of this retrospective study was to assess the diagnostic accuracy of multimodal MR imaging (diffusion, perfusion, MR spectroscopy) in the distinction of pediatric brain tumor grades and types. Seventy-six patients (range 1 month to 18 years) with brain tumors underwent multimodal MR imaging. Tumors were categorized by grade (I-IV) and by histological type (A-H). Multivariate statistical analysis was performed to evaluate the diagnostic accuracy of single and combined MR modalities, and of single imaging parameters to distinguish the different groups. The highest diagnostic accuracy for tumor grading was obtained with diffusion-perfusion (73.24%) and for tumor typing with diffusion-perfusion-MR spectroscopy (55.76%). The best diagnostic accuracy was obtained for tumor grading in I and IV and for tumor typing in embryonal tumor and pilocytic astrocytoma. Poor accuracy was seen in other grades and types. ADC and rADC were the best parameters for tumor grading and typing followed by choline level with an intermediate echo time, CBV for grading and Tmax for typing. Multiparametric MR imaging can be accurate in determining tumor grades (primarily grades I and IV) and types (mainly pilocytic astrocytomas and embryonal tumors) in children.

Attribute-Level and Pattern-Level Classification Consistency and Accuracy Indices for Cognitive Diagnostic Assessment

ERIC Educational Resources Information Center

Wang, Wenyi; Song, Lihong; Chen, Ping; Meng, Yaru; Ding, Shuliang

2015-01-01

Classification consistency and accuracy are viewed as important indicators for evaluating the reliability and validity of classification results in cognitive diagnostic assessment (CDA). Pattern-level classification consistency and accuracy indices were introduced by Cui, Gierl, and Chang. However, the indices at the attribute level have not yet…

123I-MIBG scintigraphy and 18F-FDG-PET imaging for diagnosing neuroblastoma.

PubMed

Bleeker, Gitta; Tytgat, Godelieve A M; Adam, Judit A; Caron, Huib N; Kremer, Leontien C M; Hooft, Lotty; van Dalen, Elvira C

2015-09-29

Neuroblastoma is an embryonic tumour of childhood that originates in the neural crest. It is the second most common extracranial malignant solid tumour of childhood.Neuroblastoma cells have the unique capacity to accumulate Iodine-123-metaiodobenzylguanidine (¹²³I-MIBG), which can be used for imaging the tumour. Moreover, ¹²³I-MIBG scintigraphy is not only important for the diagnosis of neuroblastoma, but also for staging and localization of skeletal lesions. If these are present, MIBG follow-up scans are used to assess the patient's response to therapy. However, the sensitivity and specificity of ¹²³I-MIBG scintigraphy to detect neuroblastoma varies according to the literature.Prognosis, treatment and response to therapy of patients with neuroblastoma are currently based on extension scoring of ¹²³I-MIBG scans. Due to its clinical use and importance, it is necessary to determine the exact diagnostic accuracy of ¹²³I-MIBG scintigraphy. In case the tumour is not MIBG avid, fluorine-18-fluorodeoxy-glucose ((18)F-FDG) positron emission tomography (PET) is often used and the diagnostic accuracy of this test should also be assessed. 1.1 To determine the diagnostic accuracy of ¹²³I-MIBG (single photon emission computed tomography (SPECT), with or without computed tomography (CT)) scintigraphy for detecting a neuroblastoma and its metastases at first diagnosis or at recurrence in children from 0 to 18 years old.1.2 To determine the diagnostic accuracy of negative ¹²³I-MIBG scintigraphy in combination with (18)F-FDG-PET(-CT) imaging for detecting a neuroblastoma and its metastases at first diagnosis or at recurrence in children from 0 to 18 years old, i.e. an add-on test. 2.1 To determine the diagnostic accuracy of (18)F-FDG-PET(-CT) imaging for detecting a neuroblastoma and its metastases at first diagnosis or at recurrence in children from 0 to 18 years old.2.2 To compare the diagnostic accuracy of ¹²³I-MIBG (SPECT-CT) and (18)F-FDG-PET(-CT) imaging for detecting a neuroblastoma and its metastases at first diagnosis or at recurrence in children from 0 to 18 years old. This was performed within and between included studies. ¹²³I-MIBG (SPECT-CT) scintigraphy was the comparator test in this case. We searched the databases of MEDLINE/PubMed (1945 to 11 September 2012) and EMBASE/Ovid (1980 to 11 September 2012) for potentially relevant articles. Also we checked the reference lists of relevant articles and review articles, scanned conference proceedings and searched for unpublished studies by contacting researchers involved in this area. We included studies of a cross-sectional design or cases series of proven neuroblastoma, either retrospective or prospective, if they compared the results of ¹²³I-MIBG (SPECT-CT) scintigraphy or (18)F-FDG-PET(-CT) imaging, or both, with the reference standards or with each other. Studies had to be primary diagnostic and report on children aged between 0 to 18 years old with a neuroblastoma of any stage at first diagnosis or at recurrence. One review author performed the initial screening of identified references. Two review authors independently performed the study selection, extracted data and assessed the methodological quality.We used data from two-by-two tables, describing at least the number of patients with a true positive test and the number of patients with a false negative test, to calculate the sensitivity, and if possible, the specificity for each included study.If possible, we generated forest plots showing estimates of sensitivity and specificity together with 95% confidence intervals. Eleven studies met the inclusion criteria. Ten studies reported data on patient level: the scan was positive or negative. One study reported on all single lesions (lesion level). The sensitivity of ¹²³I-MIBG (SPECT-CT) scintigraphy (objective 1.1), determined in 608 of 621 eligible patients included in the 11 studies, varied from 67% to 100%. One study, that reported on a lesion level, provided data to calculate the specificity: 68% in 115 lesions in 22 patients. The sensitivity of ¹²³I-MIBG scintigraphy for detecting metastases separately from the primary tumour in patients with all neuroblastoma stages ranged from 79% to 100% in three studies and the specificity ranged from 33% to 89% for two of these studies.One study reported on the diagnostic accuracy of (18)F-FDG-PET(-CT) imaging (add-on test) in patients with negative ¹²³I-MIBG scintigraphy (objective 1.2). Two of the 24 eligible patients with proven neuroblastoma had a negative ¹²³I-MIBG scan and a positive (18)F-FDG-PET(-CT) scan.The sensitivity of (18)F-FDG-PET(-CT) imaging as a single diagnostic test (objective 2.1) and compared to ¹²³I-MIBG (SPECT-CT) (objective 2.2) was only reported in one study. The sensitivity of (18)F-FDG-PET(-CT) imaging was 100% versus 92% of ¹²³I-MIBG (SPECT-CT) scintigraphy. We could not calculate the specificity for both modalities. The reported sensitivities of ¹²³-I MIBG scintigraphy for the detection of neuroblastoma and its metastases ranged from 67 to 100% in patients with histologically proven neuroblastoma.Only one study in this review reported on false positive findings. It is important to keep in mind that false positive findings can occur. For example, physiological uptake should be ruled out, by using SPECT-CT scans, although more research is needed before definitive conclusions can be made.As described both in the literature and in this review, in about 10% of the patients with histologically proven neuroblastoma the tumour does not accumulate ¹²³I-MIBG (false negative results). For these patients, it is advisable to perform an additional test for staging and assess response to therapy. Additional tests might for example be (18)F-FDG-PET(-CT), but to be certain of its clinical value, more evidence is needed.The diagnostic accuracy of (18)F-FDG-PET(-CT) imaging in case of a negative ¹²³I-MIBG scintigraphy could not be calculated, because only very limited data were available. Also the detection of the diagnostic accuracy of index test (18)F-FDG-PET(-CT) imaging for detecting a neuroblastoma tumour and its metastases, and to compare this to comparator test ¹²³I-MIBG (SPECT-CT) scintigraphy, could not be calculated because of the limited available data at time of this search.At the start of this project, we did not expect to find only very limited data on specificity. We now consider it would have been more appropriate to use the term "the sensitivity to assess the presence of neuroblastoma" instead of "diagnostic accuracy" for the objectives.

The role of laryngoscopy in the diagnosis of spasmodic dysphonia.

PubMed

Daraei, Pedram; Villari, Craig R; Rubin, Adam D; Hillel, Alexander T; Hapner, Edie R; Klein, Adam M; Johns, Michael M

2014-03-01

Spasmodic dysphonia (SD) can be difficult to diagnose, and patients often see multiple physicians for many years before diagnosis. Improving the speed of diagnosis for individuals with SD may decrease the time to treatment and improve patient quality of life more quickly. To assess whether the diagnosis of SD can be accurately predicted through auditory cues alone without the assistance of visual cues offered by laryngoscopic examination. Single-masked, case-control study at a specialized referral center that included patients who underwent laryngoscopic examination as part of a multidisciplinary workup for dysphonia. Twenty-two patients were selected in total: 10 with SD, 5 with vocal tremor, and 7 controls without SD or vocal tremor. The laryngoscopic examination was recorded, deidentified, and edited to make 3 media clips for each patient: video alone, audio alone, and combined video and audio. These clips were randomized and presented to 3 fellowship-trained laryngologist raters (A.D.R., A.T.H., and A.M.K.), who established the most probable diagnosis for each clip. Intrarater and interrater reliability were evaluated using repeat clips incorporated in the presentations. We measured diagnostic accuracy for video-only, audio-only, and combined multimedia clips. These measures were established before data collection. Data analysis was accomplished with analysis of variance and Tukey honestly significant differences. Of patients with SD, diagnostic accuracy was 10%, 73%, and 73% for video-only, audio-only, and combined, respectively (P < .001, df = 2). Of patients with vocal tremor, diagnostic accuracy was 93%, 73%, and 100% for video-only, audio-only, and combined, respectively (P = .05, df = 2). Of the controls, diagnostic accuracy was 81%, 19%, and 62% for video-only, audio-only, and combined, respectively (P < .001, df = 2). The diagnosis of SD during examination is based primarily on auditory cues. Viewing combined audio and video clips afforded no change in diagnostic accuracy compared with audio alone. Laryngoscopy serves an important role in the diagnosis of SD by excluding other pathologic causes and identifying vocal tremor.

Modeling companion diagnostics in economic evaluations of targeted oncology therapies: systematic review and methodological checklist.

PubMed

Doble, Brett; Tan, Marcus; Harris, Anthony; Lorgelly, Paula

2015-02-01

The successful use of a targeted therapy is intrinsically linked to the ability of a companion diagnostic to correctly identify patients most likely to benefit from treatment. The aim of this study was to review the characteristics of companion diagnostics that are of importance for inclusion in an economic evaluation. Approaches for including these characteristics in model-based economic evaluations are compared with the intent to describe best practice methods. Five databases and government agency websites were searched to identify model-based economic evaluations comparing a companion diagnostic and subsequent treatment strategy to another alternative treatment strategy with model parameters for the sensitivity and specificity of the companion diagnostic (primary synthesis). Economic evaluations that limited model parameters for the companion diagnostic to only its cost were also identified (secondary synthesis). Quality was assessed using the Quality of Health Economic Studies instrument. 30 studies were included in the review (primary synthesis n = 12; secondary synthesis n = 18). Incremental cost-effectiveness ratios may be lower when the only parameter for the companion diagnostic included in a model is the cost of testing. Incorporating the test's accuracy in addition to its cost may be a more appropriate methodological approach. Altering the prevalence of the genetic biomarker, specific population tested, type of test, test accuracy and timing/sequence of multiple tests can all impact overall model results. The impact of altering a test's threshold for positivity is unknown as it was not addressed in any of the included studies. Additional quality criteria as outlined in our methodological checklist should be considered due to the shortcomings of standard quality assessment tools in differentiating studies that incorporate important test-related characteristics and those that do not. There is a need to refine methods for incorporating the characteristics of companion diagnostics into model-based economic evaluations to ensure consistent and transparent reimbursement decisions are made.

Accuracy of Skin Cancer Diagnosis by Physician Assistants Compared With Dermatologists in a Large Health Care System.

PubMed

Anderson, Alyce M; Matsumoto, Martha; Saul, Melissa I; Secrest, Aaron M; Ferris, Laura K

2018-05-01

Physician assistants (PAs) are increasingly used in dermatology practices to diagnose skin cancers, although, to date, their diagnostic accuracy compared with board-certified dermatologists has not been well studied. To compare diagnostic accuracy for skin cancer of PAs with that of dermatologists. Medical record review of 33 647 skin cancer screening examinations in 20 270 unique patients who underwent screening at University of Pittsburgh Medical Center-affiliated dermatology offices from January 1, 2011, to December 31, 2015. International Classification of Diseases, Ninth Revision code V76.43 and International Classification of Diseases and Related Health Problems, Tenth Revision code Z12.83 were used to identify pathology reports from skin cancer screening examinations by dermatologists and PAs. Examination performed by a PA or dermatologist. Number needed to biopsy (NNB) to diagnose skin cancer (nonmelanoma, invasive melanoma, or in situ melanoma). Of 20 270 unique patients, 12 722 (62.8%) were female, mean (SD) age at the first visit was 52.7 (17.4) years, and 19 515 patients (96.3%) self-reported their race/ethnicity as non-Hispanic white. To diagnose 1 case of skin cancer, the NNB was 3.9 for PAs and 3.3 for dermatologists (P < .001). Per diagnosed melanoma, the NNB was 39.4 for PAs and 25.4 for dermatologists (P = .007). Patients screened by a PA were significantly less likely than those screened by a dermatologist to be diagnosed with melanoma in situ (1.1% vs 1.8% of visits, P = .02), but differences were not significant for invasive melanoma (0.7% vs 0.8% of visits, P = .83) or nonmelanoma skin cancer (6.1% vs 6.1% of visits, P = .98). Compared with dermatologists, PAs performed more skin biopsies per case of skin cancer diagnosed and diagnosed fewer melanomas in situ, suggesting that the diagnostic accuracy of PAs may be lower than that of dermatologists. Although the availability of PAs may help increase access to care and reduce waiting times for appointments, these findings have important implications for the training, appropriate scope of practice, and supervision of PAs and other nonphysician practitioners in dermatology.

Spectral-Domain Optical Coherence Tomography for Glaucoma Diagnosis

PubMed Central

Gracitelli, Carolina P.B; Abe, Ricardo Y; Medeiros, Felipe A

2015-01-01

Identification of structural damage to the optic nerve and retinal nerve fiber layer (RNFL) is an essential component of diagnosis and management of glaucoma. The introduction of spectral-domain OCT (SD-OCT) has allowed objective quantification of damage to these structures with unprecedented resolution. In addition, recent attention has been directed towards imaging the macular area for quantifying loss of neural tissue caused by the disease. Many studies have evaluated and compared the diagnostic accuracies of a variety of parameters that can be obtained from imaging these areas of the ocular fundus. In this article, we critically review the existing literature evaluating the diagnostic accuracy of SD-OCT in glaucoma and we discuss issues related to how SD-OCT results should be incorporated into clinical practice. PMID:26069519

A real-time spectral mapper as an emerging diagnostic technology in biomedical sciences.

PubMed

Epitropou, George; Kavvadias, Vassilis; Iliou, Dimitris; Stathopoulos, Efstathios; Balas, Costas

2013-01-01

Real time spectral imaging and mapping at video rates can have tremendous impact not only on diagnostic sciences but also on fundamental physiological problems. We report the first real-time spectral mapper based on the combination of snap-shot spectral imaging and spectral estimation algorithms. Performance evaluation revealed that six band imaging combined with the Wiener algorithm provided high estimation accuracy, with error levels lying within the experimental noise. High accuracy is accompanied with much faster, by 3 orders of magnitude, spectral mapping, as compared with scanning spectral systems. This new technology is intended to enable spectral mapping at nearly video rates in all kinds of dynamic bio-optical effects as well as in applications where the target-probe relative position is randomly and fast changing.

High-resolution endoscopic ultrasound imaging and the number of needle passages are significant factors predicting high yield of endoscopic ultrasound-guided fine needle aspiration for pancreatic solid masses without an on-site cytopathologist

PubMed Central

Jeong, Seok Hoo; Yoon, Hyun Hwa; Kim, Eui Joo; Kim, Yoon Jae; Kim, Yeon Suk; Cho, Jae Hee

2017-01-01

Abstract Endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) is the accurate diagnostic method for pancreatic masses and its accuracy is affected by various FNA methods and EUS equipment. Therefore, we aimed to elucidate the instrumental and methodologic factors for determining the diagnostic yield of EUS-FNA for pancreatic solid masses without an on-site cytopathology evaluation. We retrospectively reviewed the medical records of 260 patients (265 pancreatic solid masses) who underwent EUS-FNA. We compared historical conventional EUS groups with high-resolution imaging devices and finally analyzed various factors affecting EUS-FNA accuracy. In total, 265 pancreatic solid masses of 260 patients were included in this study. The accuracy, sensitivity, specificity, positive predictive value, and negative predictive value of EUS-FNA for pancreatic solid masses without on-site cytopathology evaluation were 83.4%, 81.8%, 100.0%, 100.0%, and 34.3%, respectively. In comparison with conventional image group, high-resolution image group showed the increased accuracy, sensitivity and specificity of EUS-FNA (71.3% vs 92.7%, 68.9% vs 91.9%, and 100% vs 100%, respectively). On the multivariate analysis with various instrumental and methodologic factors, high-resolution imaging (P = 0.040, odds ratio = 3.28) and 3 or more needle passes (P = 0.039, odds ratio = 2.41) were important factors affecting diagnostic yield of pancreatic solid masses. High-resolution imaging and 3 or more passes were the most significant factors influencing diagnostic yield of EUS-FNA in patients with pancreatic solid masses without an on-site cytopathologist. PMID:28079803

Diagnostic accuracy of the postoperative ratio of C-reactive protein to albumin for complications after colorectal surgery.

PubMed

Ge, Xiaolong; Cao, Yu; Wang, Hongkan; Ding, Chao; Tian, Hongliang; Zhang, Xueying; Gong, Jianfeng; Zhu, Weiming; Li, Ning

2017-01-10

The ratio of C-reactive protein to albumin, as a novel inflammation-based prognostic score, is associated with outcomes in cancer and septic patients. The diagnostic accuracy of the CRP/albumin ratio has not been assessed in colorectal surgery for postoperative complications. A total of 359 patients undergoing major colorectal surgery between 2012 and 2015 were eligible for this study. Uni- and multivariate analyses were performed to identify risk factors for postoperative complications. Receiver operating characteristic curves were developed to examine the cutoff values and diagnostic accuracy of the CRP/albumin ratio and postoperative CRP levels. Among all the patients, 139 (38.7%) were reported to have postoperative complications. The CRP/albumin ratio was an independent risk factor for complications (OR 4.413; 95% CI 2.463-7.906; P < 0.001), and the cutoff value was 2.2, which had a higher area under the curve compared to CRP on postoperative day 3 (AUC 0.779 vs 0.756). The CRP/albumin ratio also had a higher positive predictive value than CRP levels on postoperative day 3. Patients with CRP/albumin ≥2.2 suffered more postoperative complications (60.8% vs 18.6%, P < 0.001), longer postoperative stays (10 (4-71) vs 7 (3-78) days, P < 0.001), and increased surgical site infections (SSIs) (21.1% vs 4.8%, P < 0.001) than those with CRP/albumin <2.2. The ratio of C-reactive protein to albumin could help to identify patients who have a high probability of postoperative complications, and the ratio has higher diagnostic accuracy than C-reactive protein alone for postoperative complications in colorectal surgery.

Diagnostic Accuracy of a Self-Report Measure of Patellar Tendinopathy in Youth Basketball.

PubMed

Owoeye, Oluwatoyosi B A; Wiley, J Preston; Walker, Richard E A; Palacios-Derflingher, Luz; Emery, Carolyn A

2018-04-27

Study Design Prospective diagnostic accuracy validation study. Background Engaging clinicians for diagnosis of patellar tendinopathy in large surveillance studies is often impracticable. A self-report measure, the Oslo Sports Research Trauma Centre patellar tendinopathy (OSTRC-P) Questionnaire, an adaptation of the OSTRC Questionnaire may provide a viable alternative. Objectives To evaluate the diagnostic accuracy of the OSTRC-P Questionnaire in detecting patellar tendinopathy in youth basketball players when compared to clinical evaluation. Methods Following the Standards for Reporting of Diagnostic Accuracy Studies guidelines, 208 youth basketball players (aged 13-18 years) were recruited. Participants completed the OSTRC-P Questionnaire (index test) prior to a clinical evaluation (reference standard) by a physiotherapist blinded to OSTRC-P Questionnaire results. Sensitivity, specificity, predictive values (PVs), likelihood ratios (LRs) and posttest probabilities were calculated. Linear regression was used to examine the association between OSTRC-P Questionnaire severity score and patellar tendinopathy severity rating during single leg decline squat (SLDS). Results The final analysis included 169 players. The OSTRC-P Questionnaire had a sensitivity of 79% (95%CI: 65%, 90%), specificity of 98% (95%CI: 94%, 100%), positive PV of 95%, negative PV of 92%, positive LR of 48 and negative LR of 0.21. The posttest probabilities were 95% and 8% given positive and negative results, respectively. A positive association was found between OSTRC-P Questionnaire and SLDS rating [(β = .08 (95%CI: .03, .12) (p = .001)]. Conclusions The OSTRC-P Questionnaire is an acceptable alternative to clinical evaluation for self-reporting patellar tendinopathy and grading its severity in settings involving youth basketball players. Level of Evidence Diagnosis, level 1b. J Orthop Sports Phys Ther, Epub 27 Apr 2018. doi:10.2519/jospt.2018.8088.

Deep-learning derived features for lung nodule classification with limited datasets

NASA Astrophysics Data System (ADS)

Thammasorn, P.; Wu, W.; Pierce, L. A.; Pipavath, S. N.; Lampe, P. D.; Houghton, A. M.; Haynor, D. R.; Chaovalitwongse, W. A.; Kinahan, P. E.

2018-02-01

Only a few percent of indeterminate nodules found in lung CT images are cancer. However, enabling earlier diagnosis is important to avoid invasive procedures or long-time surveillance to those benign nodules. We are evaluating a classification framework using radiomics features derived with a machine learning approach from a small data set of indeterminate CT lung nodule images. We used a retrospective analysis of 194 cases with pulmonary nodules in the CT images with or without contrast enhancement from lung cancer screening clinics. The nodules were contoured by a radiologist and texture features of the lesion were calculated. In addition, sematic features describing shape were categorized. We also explored a Multiband network, a feature derivation path that uses a modified convolutional neural network (CNN) with a Triplet Network. This was trained to create discriminative feature representations useful for variable-sized nodule classification. The diagnostic accuracy was evaluated for multiple machine learning algorithms using texture, shape, and CNN features. In the CT contrast-enhanced group, the texture or semantic shape features yielded an overall diagnostic accuracy of 80%. Use of a standard deep learning network in the framework for feature derivation yielded features that substantially underperformed compared to texture and/or semantic features. However, the proposed Multiband approach of feature derivation produced results similar in diagnostic accuracy to the texture and semantic features. While the Multiband feature derivation approach did not outperform the texture and/or semantic features, its equivalent performance indicates promise for future improvements to increase diagnostic accuracy. Importantly, the Multiband approach adapts readily to different size lesions without interpolation, and performed well with relatively small amount of training data.

The diagnostic accuracy of the MyDiagnostick to detect atrial fibrillation in primary care

PubMed Central

2014-01-01

Background Atrial fibrillation is very common in people aged 65 or older. This condition increases the risk of death, congestive heart failure and thromboembolic conditions. Many patients with atrial fibrillation are asymptomatic and a cerebrovascular accident (CVA) is often the first clinical presentation. Guidelines concerning the prevention of CVA recommend monitoring the heart rate in patients aged 65 or older. Recently, the MyDiagnostick (Applied Biomedical Systems BV, Maastricht, The Netherlands) was introduced as a new screening tool which might serve as an alternative for the less accurate pulse palpation. This study was designed to explore the diagnostic accuracy of the MyDiagnostick for the detection of atrial fibrillation. Methods A phase II diagnostic accuracy study in a convenience sample of 191 subjects recruited in primary care. The majority of participants were patients with a known history of atrial fibrillation (n = 161). Readings of the MyDiagnostick were compared with electrocardiographic recordings. Sensitivity and specificity and their 95% confidence interval were calculated using 2x2 tables. Results A prevalence of 54% for an atrial fibrillation rhythm was found in the study population at the moment of the study. A combination of three measurements with the MyDiagnostick for each patient showed a sensitivity of 94% (95% CI 87 – 98) and a specificity of 93% (95% CI 85 – 97). Conclusion The MyDiagnostick is an easy-to-use device that showed a good diagnostic accuracy with a high sensitivity and specificity for atrial fibrillation in a convenience sample in primary care. Future research is needed to determine the place of the MyDiagnostick in possible screening or case-finding strategies for atrial fibrillation. PMID:24913608

Diagnostic accuracy of contrast-enhanced computed tomography and contrast-enhanced magnetic resonance imaging of small renal masses in real practice: sensitivity and specificity according to subjective radiologic interpretation.

PubMed

Kim, Jae Heon; Sun, Hwa Yeon; Hwang, Jiyoung; Hong, Seong Sook; Cho, Yong Jin; Doo, Seung Whan; Yang, Won Jae; Song, Yun Seob

2016-10-12

The aim of this study was to investigate the diagnostic accuracy of contrast-enhanced computed tomography (CT) and contrast-enhanced magnetic resonance imaging (MRI) of small renal masses in real practice. Contrast-enhanced CT and MRI were performed between February 2008 and February 2013 on 68 patients who had suspected small (≤4 cm) renal cell carcinoma (RCC) based on ultrasonographic measurements. CT and MRI radiographs were reviewed, and the findings of small renal masses were re-categorized into five dichotomized scales by the same two radiologists who had interpreted the original images. Receiver operating characteristics curve analysis was performed, and sensitivity and specificity were determined. Among the 68 patients, 60 (88.2 %) had RCC and eight had benign disease. The diagnostic accuracy rates of contrast-enhanced CT and MRI were 79.41 and 88.23 %, respectively. Diagnostic accuracy was greater when using contrast-enhanced MRI because too many masses (67.6 %) were characterized as "4 (probably solid cancer) or 5 (definitely solid cancer)." The sensitivity of contrast-enhanced CT and MRI for predicting RCC were 79.7 and 88.1 %, respectively. The specificities of contrast-enhanced CT and MRI for predicting RCC were 44.4 and 33.3 %, respectively. Fourteen diagnoses (20.5 %) were missed or inconsistent compared with the final pathological diagnoses. One appropriate nephroureterectomy and five unnecessary percutaneous biopsies were performed for RCC. Seven unnecessary partial nephrectomies were performed for benign disease. Although contrast-enhanced CT and MRI showed high sensitivity for detecting small renal masses, specificity remained low.

The diagnostic accuracy of a laser fluorescence device and digital radiography in detecting approximal caries lesions in posterior permanent teeth: an in vivo study.

PubMed

Menem, R; Barngkgei, I; Beiruti, N; Al Haffar, I; Joury, Easter

2017-04-01

The aim of this in vivo study was to test the diagnostic accuracy of a pen-type laser fluorescence (LFpen) device in detecting approximal caries lesions, in posterior permanent teeth, at the cavitation and non-cavitation thresholds, and compare it with that of digital bitewing radiography. Thirty patients (aged 18-37), who attended the Faculty of Dentistry at Damascus University for a dental examination, were consecutively screened. Ninety approximal surfaces of posterior permanent teeth without frank cavitations, enamel hypoplasia or restorations were selected and examined using the LFpen (DIAGNOdent pen) and digital bitewing radiography. The reference standard was the visual-tactile inspection, after performing temporary tooth separation, using orthodontic rubber rings, placed for 7 days. The status of included approximal surfaces was recorded as intact/sound, with white/brown spots or cavitated. One trained examiner performed all examinations. There were statistically significant differences in LFpen readings between the three types of approximal surface status (P < 0.001). The optimal cut-off values for detecting approximal caries lesions in posterior permanent teeth were >16 and 8 at the cavitation and non-cavitation thresholds respectively. The sensitivity, specificity and accuracy (measured by the area under the receiver-operating characteristic curve) were 100, 85 and 95 and 92, 90 and 95% at the cavitation and non-cavitation thresholds respectively. The intra-class correlation coefficient for intra-examiner reliability was 0.95. The diagnostic accuracy of the LFpen was significantly higher than that of digital bitewing radiography (P < 0.001). The LFpen's diagnostic performance was accurate and significantly better than digital bitewing radiography in detecting approximal caries lesions, in posterior permanent teeth.

Sublingual Nitroglycerin Administration in Coronary Computed Tomography Angiography: a Systematic Review.

PubMed

Takx, Richard A P; Suchá, Dominika; Park, Jakob; Leiner, Tim; Hoffmann, Udo

2015-12-01

To systematically investigate the literature for the influence of sublingual nitroglycerin administration on coronary diameter, the number of evaluable segments, image quality, heart rate and blood pressure, and diagnostic accuracy of coronary computed tomography (CT) angiography. A systematic search was performed in PubMed, EMBASE and Web of Science. The studies were evaluated for the effect of sublingual nitroglycerin on coronary artery diameter, evaluable segments, objective and subjective image quality, systemic physiological effects and diagnostic accuracy. Due to the heterogeneous reporting of outcome measures, a narrative synthesis was applied. Of the 217 studies identified, nine met the inclusion criteria: seven reported on the effect of nitroglycerin on coronary artery diameter, six on evaluable segments, four on image quality, five on systemic physiological effects and two on diagnostic accuracy. Sublingual nitroglycerin administration resulted in an improved evaluation of more coronary segments, in particular, in smaller coronary branches, better image quality and improved diagnostic accuracy. Side effects were mild and were alleviated without medical intervention. Sublingual nitroglycerin improves the coronary diameter, the number of assessable segments, image quality and diagnostic accuracy of coronary CT angiography without major side effects or systemic physiological changes. • Sublingual nitroglycerin administration results in significant coronary artery dilatation. • Nitroglycerin increases the number of evaluable coronary branches. • Image quality is improved the most in smaller coronary branches. • Nitroglycerin increases the diagnostic accuracy of coronary CT angiography. • Most side effects are mild and do not require medical intervention.

Diagnostic accuracies of procalcitonin and C-reactive protein for bacterial infection in patients with systemic rheumatic diseases: a meta-analysis.

PubMed

Song, Gwan Gyu; Bae, Sang-Cheol; Lee, Young Ho

2015-01-01

The purpose of this study was to compare the diagnostic performance of procalcitonin and C-reactive protein (CRP) for bacterial infection in patients with systemic rheumatic diseases. We searched Medline, Embase, and the Cochran library, and performed two meta-analyses on the diagnostic accuracy of procalcitonin and CRP for bacterial infection in systemic rheumatic disease patients. A total of eight studies including 668 patients in whom the patients with bacterial infection were 208 were available for the meta-analysis. The pooled sensitivity and specificity of procalcitonin were 66.8% (95% confidence interval [CI] 60.0-73.2) and 89.8% (86.6-92.4), respectively, and those of CRP were 81.3% (75.3-86.3) and 63.0% (58.5-67.5). Procalcitonin PLR, NLR, and DOR were 5.930 (3.593-9.786), 0.352 (0.229-0.539), and 19.33 (10.25-36.45), respectively, and those for CRP were 2.228 (1.376-3.608), 0.367 (0.252-0.534), and 7.066 (3.559-14.03), respectively. The AUC of procalcitonin was 0.884 and the Q* index was 0.814, while the AUC of CRP was 0.789 and the Q* index was 0.726, which indicated that the diagnostic accuracy of procalcitonin in patients with systemic rheumatic diseases is higher than that of CRP (difference of AUC 0.095, 95% CI 0.004-0.185, p=0.039). When the data were limited to SLE, the specificity of procalcitonin was also significantly higher than that of CRP (difference 0.219, 95% CI 0.127-0.310, p<0.0001). Our meta-analysis of published studies demonstrates that procalcitonin is more specific and has better diagnostic accuracy than CRP for bacterial infection in systemic rheumatic diseases.

Diagnostic accuracy of three monoclonal stool tests in a large series of untreated Helicobacter pylori infected patients.

PubMed

Lario, Sergio; Ramírez-Lázaro, María José; Montserrat, Antònia; Quílez, María Elisa; Junquera, Félix; Martínez-Bauer, Eva; Sanfeliu, Isabel; Brullet, Enric; Campo, Rafael; Segura, Ferran; Calvet, Xavier

2016-06-01

Immunochromatographic tests need to be improved in order to enhance their reliability. Recently, several new kits have appeared on the market. The objective was to evaluate the diagnostic accuracy of three monoclonal rapid stool tests - the new Uni-Gold™ H.pylori Antigen (Trinity Biotech, Ireland), the RAPID Hp StAR (Oxoid Ltd., UK) and the ImmunoCard STAT! HpSA (Meridian Diagnostics, USA) - for detecting H. pylori infection prior to eradication treatment. Diagnostic accuracy (sensitivity and specificity) and reliability (concordance between observers) were evaluated in 250 untreated consecutive dyspeptic patients. The gold standard for diagnosing H. pylori infection was defined as the concordance of two or more of rapid urease test (RUT), histopathology and urease breath test (UBT) or positive culture in isolation. Readings of immunochromatographic tests were performed by two different observers. Sensitivity, specificity, positive and negative predictive values and 95% confidence intervals were calculated. Sensitivity and specificity were compared using the McNemar test. The three tests showed a good correlation, with Kappa values>0.9. RAPID Hp StAR had a sensitivity of 91%-92% and a specificity ranging from 77% to 85%. Its sensitivity was higher than that of Uni-Gold™ H.pylori Antigen and ImmunoCard STAT! HpSA (p<0.01). Uni-Gold™ H.pylori Antigen kit showed a sensitivity of 83%, similar to ImmunoCard STAT! HpSA. Specificity of Uni-Gold™ H.pylori Antigen approached 90% (87-89%) and was superior to that of RAPID Hp StAR (p<0.01). Uni-Gold™ H.pylori Antigen and ImmunoCard STAT! HpSA present similar levels of diagnostic accuracy. RAPID Hp StAR was the most sensitive but less reliable of the three immunochromatographic stool tests. None are as accurate and reliable as UBT, RUT and histology. Copyright © 2016 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.

Limited diagnostic accuracy of magnetic resonance imaging and clinical tests for detecting partial-thickness tears of the rotator cuff.

PubMed

Brockmeyer, Matthias; Schmitt, Cornelia; Haupert, Alexander; Kohn, Dieter; Lorbach, Olaf

2017-12-01

The reliable diagnosis of partial-thickness tears of the rotator cuff is still elusive in clinical practise. Therefore, the purpose of the study was to determine the diagnostic accuracy of MR imaging and clinical tests for detecting partial-thickness tears of the rotator cuff as well as the combination of these parameters. 334 consecutive shoulder arthroscopies for rotator cuff pathologies performed during the time period between 2010 and 2012 were analyzed retrospectively for the findings of common clinical signs for rotator cuff lesions and preoperative MR imaging. These were compared with the intraoperative arthroscopic findings as "gold standard". The reports of the MR imaging were evaluated with regard to the integrity of the rotator cuff. The Ellman Classification was used to define partial-thickness tears of the rotator cuff in accordance with the arthroscopic findings. Descriptive statistics, sensitivity, specificity, positive and negative predictive value were calculated. MR imaging showed 80 partial-thickness and 70 full-thickness tears of the rotator cuff. The arthroscopic examination confirmed 64 partial-thickness tears of which 52 needed debridement or refixation of the rotator cuff. Sensitivity for MR imaging to identify partial-thickness tears was 51.6%, specificity 77.2%, positive predictive value 41.3% and negative predictive value 83.7%. For the Jobe-test, sensitivity was 64.1%, specificity 43.2%, positive predictive value 25.9% and negative predictive value 79.5%. Sensitivity for the Impingement-sign was 76.7%, specificity 46.6%, positive predictive value 30.8% and negative predictive value 86.5%. For the combination of MR imaging, Jobe-test and Impingement-sign sensitivity was 46.9%, specificity 85.4%, positive predictive value 50% and negative predictive value 83.8%. The diagnostic accuracy of MR imaging and clinical tests (Jobe-test and Impingement-sign) alone is limited for detecting partial-thickness tears of the rotator cuff. Additionally, the combination of MR imaging and clinical tests does not improve diagnostic accuracy. Level II, Diagnostic study.

Clinical diagnosis of ventilator associated pneumonia revisited: comparative validation using immediate post-mortem lung biopsies

PubMed Central

Fabregas, N.; Ewig, S.; Torres, A.; El-Ebiary, M.; Ramirez, J.; de la Bellacasa, J. P.; Bauer, T.; Cabello, H.

1999-01-01

BACKGROUND—A study was undertaken to assess the diagnostic value of different clinical criteria and the impact of microbiological testing on the accuracy of clinical diagnosis of suspected ventilator associated pneumonia (VAP).
METHODS—Twenty five deceased mechanically ventilated patients were studied prospectively. Immediately after death, multiple bilateral lung biopsy specimens (16 specimens/patient) were obtained for histological examination and quantitative lung cultures. The presence of both histological pneumonia and positive lung cultures was used as a reference test.
RESULTS—The presence of infiltrates on the chest radiograph and two of three clinical criteria (leucocytosis, purulent secretions, fever) had a sensitivity of 69% and a specificity of 75%; the corresponding numbers for the clinical pulmonary infection score (CPIS) were 77% and 42%. Non-invasive as well as invasive sampling techniques had comparable values. The combination of all techniques achieved a sensitivity of 85% and a specificity of 50%, and these values remained virtually unchanged despite the presence of previous treatment with antibiotics. When microbiological results were added to clinical criteria, adequate diagnoses originating from microbiological results which might have corrected false positive and false negative clinical judgements (n = 5) were countered by a similar proportion of inadequate diagnoses (n =6).
CONCLUSIONS—Clinical criteria had reasonable diagnostic values. CPIS was not superior to conventional clinical criteria. Non-invasive and invasive sampling techniques had diagnostic values comparable to clinical criteria. An algorithm guiding antibiotic treatment exclusively by microbiological results does not increase the overall diagnostic accuracy and carries the risk of undertreatment.

 PMID:10491448

Evaluation of the accuracy of the EasyTest™ malaria Pf/Pan Ag, a rapid diagnostic test, in Uganda.

PubMed

Chong, Chom-Kyu; Cho, Pyo Yun; Na, Byoung-Kuk; Ahn, Seong Kyu; Kim, Jin Su; Lee, Jin-Soo; Lee, Sung-Keun; Han, Eun-Taek; Kim, Hak-Yong; Park, Yun-Kyu; Cha, Seok Ho; Kim, Tong-Soo

2014-10-01

In recent years, rapid diagnostic tests (RDTs) have been widely used for malaria detection, primarily because of their simple operation, fast results, and straightforward interpretation. The Asan EasyTest™ Malaria Pf/Pan Ag is one of the most commonly used malaria RDTs in several countries, including Korea and India. In this study, we tested the diagnostic performance of this RDT in Uganda to evaluate its usefulness for field diagnosis of malaria in this country. Microscopic and PCR analyses, and the Asan EasyTest™ Malaria Pf/Pan Ag rapid diagnostic test, were performed on blood samples from 185 individuals with suspected malaria in several villages in Uganda. Compared to the microscopic analysis, the sensitivity of the RDT to detect malaria infection was 95.8% and 83.3% for Plasmodium falciparum and non-P. falciparum, respectively. Although the diagnostic sensitivity of the RDT decreased when parasitemia was ≤500 parasites/µl, it showed 96.8% sensitivity (98.4% for P. falciparum and 93.8% for non-P. falciparum) in blood samples with parasitemia ≥100 parasites/µl. The specificity of the RDT was 97.3% for P. falciparum and 97.3% for non-P. falciparum. These results collectively suggest that the accuracy of the Asan EasyTest™ Malaria Pf/Pan Ag makes it an effective point-of-care diagnostic tool for malaria in Uganda.

Evaluation of the Accuracy of the EasyTest™ Malaria Pf/Pan Ag, a Rapid Diagnostic Test, in Uganda

PubMed Central

Chong, Chom-Kyu; Cho, Pyo Yun; Na, Byoung-Kuk; Ahn, Seong Kyu; Kim, Jin Su; Lee, Jin-Soo; Lee, Sung-Keun; Han, Eun-Taek; Kim, Hak-Yong; Park, Yun-Kyu; Cha, Seok Ho

2014-01-01

In recent years, rapid diagnostic tests (RDTs) have been widely used for malaria detection, primarily because of their simple operation, fast results, and straightforward interpretation. The Asan EasyTest™ Malaria Pf/Pan Ag is one of the most commonly used malaria RDTs in several countries, including Korea and India. In this study, we tested the diagnostic performance of this RDT in Uganda to evaluate its usefulness for field diagnosis of malaria in this country. Microscopic and PCR analyses, and the Asan EasyTest™ Malaria Pf/Pan Ag rapid diagnostic test, were performed on blood samples from 185 individuals with suspected malaria in several villages in Uganda. Compared to the microscopic analysis, the sensitivity of the RDT to detect malaria infection was 95.8% and 83.3% for Plasmodium falciparum and non-P. falciparum, respectively. Although the diagnostic sensitivity of the RDT decreased when parasitemia was ≤500 parasites/µl, it showed 96.8% sensitivity (98.4% for P. falciparum and 93.8% for non-P. falciparum) in blood samples with parasitemia ≥100 parasites/µl. The specificity of the RDT was 97.3% for P. falciparum and 97.3% for non-P. falciparum. These results collectively suggest that the accuracy of the Asan EasyTest™ Malaria Pf/Pan Ag makes it an effective point-of-care diagnostic tool for malaria in Uganda. PMID:25352698

Design of Malaria Diagnostic Criteria for the Sysmex XE-2100 Hematology Analyzer

PubMed Central

Campuzano-Zuluaga, Germán; Álvarez-Sánchez, Gonzalo; Escobar-Gallo, Gloria Elcy; Valencia-Zuluaga, Luz Marina; Ríos-Orrego, Alexandra Marcela; Pabón-Vidal, Adriana; Miranda-Arboleda, Andrés Felipe; Blair-Trujillo, Silvia; Campuzano-Maya, Germán

2010-01-01

Thick film, the standard diagnostic procedure for malaria, is not always ordered promptly. A failsafe diagnostic strategy using an XE-2100 analyzer is proposed, and for this strategy, malaria diagnostic models for the XE-2100 were developed and tested for accuracy. Two hundred eighty-one samples were distributed into Plasmodium vivax, P. falciparum, and acute febrile syndrome groups for model construction. Model validation was performed using 60% of malaria cases and a composite control group of samples from AFS and healthy participants from endemic and non-endemic regions. For P. vivax, two observer-dependent models (accuracy = 95.3–96.9%), one non–observer-dependent model using built-in variables (accuracy = 94.7%), and one non–observer-dependent model using new and built-in variables (accuracy = 96.8%) were developed. For P. falciparum, two non–observer-dependent models (accuracies = 85% and 89%) were developed. These models could be used by health personnel or be integrated as a malaria alarm for the XE-2100 to prompt early malaria microscopic diagnosis. PMID:20207864

Store-and-forward teledermatology for the most common skin neoplasms in Ukraine.

PubMed

Kravets, Kira; Vasylenko, Olga; Dranyk, Zhanna; Bogomolets, Olga

2018-06-01

Among all malignancies in Ukraine in 2016, the group of non-melanoma skin cancers headed the list in men and made up 21.6%. This group was second in women and made up 17.6%. The diagnostics of skin tumors are becoming increasingly relevant. The store-and-forward (SAF) method was used. The study included patients that were remotely diagnosed with melanocytic nevi, seborrheic keratoses, skin cancer, and skin melanoma. Patients signed up for remote diagnostics, were examined in person by dermatologists, and had tumors excised with a subsequent histological examination. Using telemedicine, 108 melanocytic nevi, 97 seborrheic keratoses, 62 skin cancers, and 47 skin melanomas were diagnosed and selected. The accuracy of teledermatological examination and teledermoscopy compared to clinical examination and dermoscopy was 90.3 to 100.0%. The accuracy of teledermatological examination and teledermoscopy compared to histopathological diagnoses was 85.1 to 98.9%. Teledermatological diagnosis showed a high ability for detecting skin neoplasms in Ukraine.

Diagnostic accuracy of 64-slice multidetector CT angiography for detection of in-stent restenosis of vertebral artery ostium stents: comparison with conventional angiography.

PubMed

Lee, Youn Joo; Lim, Yeon Soo; Lim, Hyun Wook; Yoo, Won Jong; Choi, Byung Gil; Kim, Bum Soo

2014-10-01

There are very few reports assessing in-stent restenosis (ISR) after vertebral artery ostium (VAO) stents using multidetector computed tomography (MDCT). To compare the diagnostic accuracy of computed tomography angiography (CTA) using 64-slice MDCT with digital subtraction angiography (DSA) for detection of significant ISR after VAO stenting. The study evaluated 57 VAO stents in 57 patients (39 men, 18 women; mean age 64 years [range, 48-90 years]). All stents were scanned with a 64-slice MDCT scanner. Three sets of images were reconstructed with three different convolution kernels. Two observers who were blinded to the results of DSA assessed the diagnostic accuracy of CTA for detecting significant ISR (≥50% diameter narrowing) of VAO stents in comparison with DSA as the reference standard. The sensitivity, specificity, positive and negative predictive values, and accuracy were calculated. Of the 57 stents, 46 (81%) were assessable using CTA, while 11 (19%) were not. No stents with diameters ≤2.75 mm were assessable. DSA revealed 13 cases of significant ISR in all stents. The respective sensitivity, specificity, positive and negative predictive values, and accuracy were 92%, 82%, 60%, 97%, and 84% for all stents. On excluding the 11 non-assessable stents, the respective values were 88%, 95%, 78%, 97%, and 93%. Of the 46 CTA assessable stents, eight significant ISRs were diagnosed on DSA. Seven of eight patients with significant ISR by DSA were diagnosed correctly with CTA. The area under the receiver-operating characteristic curve (AUC) was 0.87 for all stents and 0.91 for assessable stents, indicating good to excellent agreement between CTA and DSA for detecting significant ISR after VAO stenting. Sixty-four-slice MDCT is a promising non-invasive method of assessing stent patency and can exclude significant ISR with high diagnostic values after VAO stenting. © The Foundation Acta Radiologica 2013 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

Quantitative differentiation of breast lesions at 3T diffusion-weighted imaging (DWI) using the ratio of distributed diffusion coefficient (DDC).

PubMed

Ertas, Gokhan; Onaygil, Can; Akin, Yasin; Kaya, Handan; Aribal, Erkin

2016-12-01

To investigate the accuracy of diffusion coefficients and diffusion coefficient ratios of breast lesions and of glandular breast tissue from mono- and stretched-exponential models for quantitative diagnosis in diffusion-weighted magnetic resonance imaging (MRI). We analyzed pathologically confirmed 170 lesions (85 benign and 85 malignant) imaged using a 3.0T MR scanner. Small regions of interest (ROIs) focusing on the highest signal intensity for lesions and also for glandular tissue of contralateral breast were obtained. Apparent diffusion coefficient (ADC) and distributed diffusion coefficient (DDC) were estimated by performing nonlinear fittings using mono- and stretched-exponential models, respectively. Coefficient ratios were calculated by dividing the lesion coefficient by the glandular tissue coefficient. A stretched exponential model provides significantly better fits then the monoexponential model (P < 0.001): 65% of the better fits for glandular tissue and 71% of the better fits for lesion. High correlation was found in diffusion coefficients (0.99-0.81 and coefficient ratios (0.94) between the models. The highest diagnostic accuracy was found by the DDC ratio (area under the curve [AUC] = 0.93) when compared with lesion DDC, ADC ratio, and lesion ADC (AUC = 0.91, 0.90, 0.90) but with no statistically significant difference (P > 0.05). At optimal thresholds, the DDC ratio achieves 93% sensitivity, 80% specificity, and 87% overall diagnostic accuracy, while ADC ratio leads to 89% sensitivity, 78% specificity, and 83% overall diagnostic accuracy. The stretched exponential model fits better with signal intensity measurements from both lesion and glandular tissue ROIs. Although the DDC ratio estimated by using the model shows a higher diagnostic accuracy than the ADC ratio, lesion DDC, and ADC, it is not statistically significant. J. Magn. Reson. Imaging 2016;44:1633-1641. © 2016 International Society for Magnetic Resonance in Medicine.

Comparison between a Single-Channel Nasal Airflow Device and Oximetry for the Diagnosis of Obstructive Sleep Apnea

PubMed Central

Rofail, Lydia Makarie; Wong, Keith K.H.; Unger, Gunnar; Marks, Guy B.; Grunstein, Ronald R.

2010-01-01

Rationale: The most common single channel devices used for obstructive sleep apnea (OSA) screening are nasal airflow and oximetry. No studies have directly compared their role in diagnosing OSA at home. Study Objectives: To prospectively compare the diagnostic utility of home-based nasal airflow and oximetry to attended polysomnography (PSG) and to assess the diagnostic value of adding oximetry to nasal airflow for OSA. Design: Cross-sectional study Setting: Laboratory and home Participants: Sleep clinic patients with suspected OSA. Interventions: All patients had laboratory PSG and 2 sets of 3 consecutive nights on each device; nasal airflow (Flow Wizard, DiagnoseIT, Australia) and oximetry (Radical Set, Masimo, USA) at home in random order. Results: Ninety-eight of the 105 patients enrolled completed home monitoring. The accuracy of nasal airflow respiratory disturbance index (NF RDI) was not different from oximetry (ODI 3%) for diagnosing OSA (area under the ROC curve (AUC) difference, 0.04; 95% CI of difference −0.05 to 0.12; P = 0.43) over 3 nights of at-home recording. The accuracy of NF RDI was higher after 3 nights compared to one night (AUC difference, 0.05; 95% CI of difference, 0.01 to 0.08; P = 0.04). Addition of oximetry to nasal airflow did not increase the accuracy for predicting OSA compared to nasal airflow alone (P > 0.1). Conclusions: Nasal flow and oximetry have equivalent accuracy for diagnosing OSA in the home setting. Choice of device for home screening of sleep apnea may depend on logistical and service delivery issues. Citation: Makarie Rofail L; Wong KKH; Unger G; Marks GB; Grunstein RR. Comparison between a single-channel nasal airflow device and oximetry for the diagnosis of obstructive sleep apnea. SLEEP 2010;33(8):1106-1114. PMID:20815194

Evaluation of Accuracy of DIAGNOdent in Diagnosis of Primary and Secondary Caries in Comparison to Conventional Methods

PubMed Central

Nokhbatolfoghahaie, Hanieh; Alikhasi, Marzieh; Chiniforush, Nasim; Khoei, Farzaneh; Safavi, Nassimeh; Yaghoub Zadeh, Behnoush

2013-01-01

Introduction: Today the prevalence of teeth decays has considerably decreased. Related organizations and institutions mention several reasons for it such as improvement of decay diagnostic equipment and tools which are even capable of detecting caries in their initial stages. This resulted in reduction of costs for patients and remarkable increase in teeth life span. There are many methods for decay diagnostic, like: visual and radiographic methods, devices with fluorescence such as Quantitative light-induced fluorescence (QLF), Vista proof, Laser fluorescence (LF or DIAGNOdent), Fluorescence Camera (FC) and Digital radiography. Although DIAGNOdent is considered a valuable device for decay diagnostic ,there are concerns regarding its efficacy and accuracy. Considering the sensitivity of decaydiagnosis and the exorbitant annual expenses supported by government and people for caries treatment, finding the best method for early caries detection is of the most importance. Numerous studies were performed to compare different diagnostic methods with conflicting results. The objective of this study is a comparative review of the efficiency of DIAGNOdent in comparison to visual methods and radiographic methods in the diagnostic of teeth occlusal surfaces. Methods: Search of PubMed, Google Scholar electronic resources was performed in order to find clinical trials in English in the period between 1998 and 2013. Full texts of only 35 articles were available. Conclusion: Considering the sensitivity and specificity reported in the different studies, it seems that DIAGNOdent is an appropriate modality for caries detection as a complementary method beside other methods and its use alone to obtain treatment plan is not enough. PMID:25606325

Imperfect practice makes perfect: error management training improves transfer of learning.

PubMed

Dyre, Liv; Tabor, Ann; Ringsted, Charlotte; Tolsgaard, Martin G

2017-02-01

Traditionally, trainees are instructed to practise with as few errors as possible during simulation-based training. However, transfer of learning may improve if trainees are encouraged to commit errors. The aim of this study was to assess the effects of error management instructions compared with error avoidance instructions during simulation-based ultrasound training. Medical students (n = 60) with no prior ultrasound experience were randomised to error management training (EMT) (n = 32) or error avoidance training (EAT) (n = 28). The EMT group was instructed to deliberately make errors during training. The EAT group was instructed to follow the simulator instructions and to commit as few errors as possible. Training consisted of 3 hours of simulation-based ultrasound training focusing on fetal weight estimation. Simulation-based tests were administered before and after training. Transfer tests were performed on real patients 7-10 days after the completion of training. Primary outcomes were transfer test performance scores and diagnostic accuracy. Secondary outcomes included performance scores and diagnostic accuracy during the simulation-based pre- and post-tests. A total of 56 participants completed the study. On the transfer test, EMT group participants attained higher performance scores (mean score: 67.7%, 95% confidence interval [CI]: 62.4-72.9%) than EAT group members (mean score: 51.7%, 95% CI: 45.8-57.6%) (p < 0.001; Cohen's d = 1.1, 95% CI: 0.5-1.7). There was a moderate improvement in diagnostic accuracy in the EMT group compared with the EAT group (16.7%, 95% CI: 10.2-23.3% weight deviation versus 26.6%, 95% CI: 16.5-36.7% weight deviation [p = 0.082; Cohen's d = 0.46, 95% CI: -0.06 to 1.0]). No significant interaction effects between group and performance improvements between the pre- and post-tests were found in either performance scores (p = 0.25) or diagnostic accuracy (p = 0.09). The provision of error management instructions during simulation-based training improves the transfer of learning to the clinical setting compared with error avoidance instructions. Rather than teaching to avoid errors, the use of errors for learning should be explored further in medical education theory and practice. © 2016 John Wiley & Sons Ltd and The Association for the Study of Medical Education.

Accuracy of recommended sampling and assay methods for the determination of plasma-free and urinary fractionated metanephrines in the diagnosis of pheochromocytoma and paraganglioma: a systematic review.

PubMed

Därr, Roland; Kuhn, Matthias; Bode, Christoph; Bornstein, Stefan R; Pacak, Karel; Lenders, Jacques W M; Eisenhofer, Graeme

2017-06-01

To determine the accuracy of biochemical tests for the diagnosis of pheochromocytoma and paraganglioma. A search of the PubMed database was conducted for English-language articles published between October 1958 and December 2016 on the biochemical diagnosis of pheochromocytoma and paraganglioma using immunoassay methods or high-performance liquid chromatography with coulometric/electrochemical or tandem mass spectrometric detection for measurement of fractionated metanephrines in 24-h urine collections or plasma-free metanephrines obtained under seated or supine blood sampling conditions. Application of the Standards for Reporting of Diagnostic Studies Accuracy Group criteria yielded 23 suitable articles. Summary receiver operating characteristic analysis revealed sensitivities/specificities of 94/93% and 91/93% for measurement of plasma-free metanephrines and urinary fractionated metanephrines using high-performance liquid chromatography or immunoassay methods, respectively. Partial areas under the curve were 0.947 vs. 0.911. Irrespective of the analytical method, sensitivity was significantly higher for supine compared with seated sampling, 95 vs. 89% (p < 0.02), while specificity was significantly higher for supine sampling compared with 24-h urine, 95 vs. 90% (p < 0.03). Partial areas under the curve were 0.942, 0.913, and 0.932 for supine sampling, seated sampling, and urine. Test accuracy increased linearly from 90 to 93% for 24-h urine at prevalence rates of 0.0-1.0, decreased linearly from 94 to 89% for seated sampling and was constant at 95% for supine conditions. Current tests for the biochemical diagnosis of pheochromocytoma and paraganglioma show excellent diagnostic accuracy. Supine sampling conditions and measurement of plasma-free metanephrines using high-performance liquid chromatography with coulometric/electrochemical or tandem mass spectrometric detection provides the highest accuracy at all prevalence rates.

Mean Platelet Volume, Red Cell Distribution Width to Platelet Count Ratio, Globulin Platelet Index, and 16 Other Indirect Noninvasive Fibrosis Scores: How Much Do Routine Blood Tests Tell About Liver Fibrosis in Chronic Hepatitis C?

PubMed

Thandassery, Ragesh B; Al Kaabi, Saad; Soofi, Madiha E; Mohiuddin, Syed A; John, Anil K; Al Mohannadi, Muneera; Al Ejji, Khalid; Yakoob, Rafie; Derbala, Moutaz F; Wani, Hamidullah; Sharma, Manik; Al Dweik, Nazeeh; Butt, Mohammed T; Kamel, Yasser M; Sultan, Khaleel; Pasic, Fuad; Singh, Rajvir

2016-07-01

Many indirect noninvasive scores to predict liver fibrosis are calculated from routine blood investigations. Only limited studies have compared their efficacy head to head. We aimed to compare these scores with liver biopsy fibrosis stages in patients with chronic hepatitis C. From blood investigations of 1602 patients with chronic hepatitis C who underwent a liver biopsy before initiation of antiviral treatment, 19 simple noninvasive scores were calculated. The area under the receiver operating characteristic curves and diagnostic accuracy of each of these scores were calculated (with reference to the Scheuer staging) and compared. The mean age of the patients was 41.8±9.6 years (1365 men). The most common genotype was genotype 4 (65.6%). Significant fibrosis, advanced fibrosis, and cirrhosis were seen in 65.1%, 25.6, and 6.6% of patients, respectively. All the scores except the aspartate transaminase (AST) alanine transaminase ratio, Pohl score, mean platelet volume, fibro-alpha, and red cell distribution width to platelet count ratio index showed high predictive accuracy for the stages of fibrosis. King's score (cutoff, 17.5) showed the highest predictive accuracy for significant and advanced fibrosis. King's score, Göteborg university cirrhosis index, APRI (the AST/platelet count ratio index), and Fibrosis-4 (FIB-4) had the highest predictive accuracy for cirrhosis, with the APRI (cutoff, 2) and FIB-4 (cutoff, 3.25) showing the highest diagnostic accuracy.We derived the study score 8.5 - 0.2(albumin, g/dL) +0.01(AST, IU/L) -0.02(platelet count, 10/L), which at a cutoff of >4.7 had a predictive accuracy of 0.868 (95% confidence interval, 0.833-0.904) for cirrhosis. King's score for significant and advanced fibrosis and the APRI or FIB-4 score for cirrhosis could be the best simple indirect noninvasive scores.

Systematic review and meta-analysis: rapid diagnostic tests versus placental histology, microscopy and PCR for malaria in pregnant women.

PubMed

Kattenberg, Johanna H; Ochodo, Eleanor A; Boer, Kimberly R; Schallig, Henk Dfh; Mens, Petra F; Leeflang, Mariska Mg

2011-10-28

During pregnancy, malaria infection with Plasmodium falciparum or Plasmodium vivax is related to adverse maternal health and poor birth outcomes. Diagnosis of malaria, during pregnancy, is complicated by the absence or low parasite densities in peripheral blood. Diagnostic methods, other than microscopy, are needed for detection of placental malaria. Therefore, the diagnostic accuracy of rapid diagnostic tests (RDTs), detecting antigen, and molecular techniques (PCR), detecting DNA, for the diagnosis of Plasmodium infections in pregnancy was systematically reviewed. MEDLINE, EMBASE and Web of Science were searched for studies assessing the diagnostic accuracy of RDTs, PCR, microscopy of peripheral and placental blood and placental histology for the detection of malaria infection (all species) in pregnant women. The results of 49 studies were analysed in metandi (Stata), of which the majority described P. falciparum infections. Although both placental and peripheral blood microscopy cannot reliably replace histology as a reference standard for placental P. falciparum infection, many studies compared RDTs and PCR to these tests. The proportion of microscopy positives in placental blood (sensitivity) detected by peripheral blood microscopy, RDTs and PCR are respectively 72% [95% CI 62-80], 81% [95% CI 55-93] and 94% [95% CI 86-98]. The proportion of placental blood microscopy negative women that were negative in peripheral blood microscopy, RDTs and PCR (specificity) are 98% [95% CI 95-99], 94% [95% CI 76-99] and 77% [95% CI 71-82]. Based on the current data, it was not possible to determine if the false positives in RDTs and PCR are caused by sequestered parasites in the placenta that are not detected by placental microscopy. The findings suggest that RDTs and PCR may have good performance characteristics to serve as alternatives for the diagnosis of malaria in pregnancy, besides any other limitations and practical considerations concerning the use of these tests. Nevertheless, more studies with placental histology as reference test are urgently required to reliably determine the accuracy of RDTs and PCR for the diagnosis of placental malaria. P. vivax-infections have been neglected in diagnostic test accuracy studies of malaria in pregnancy.

Systematic review and meta-analysis: rapid diagnostic tests versus placental histology, microscopy and PCR for malaria in pregnant women

PubMed Central

2011-01-01

Background During pregnancy, malaria infection with Plasmodium falciparum or Plasmodium vivax is related to adverse maternal health and poor birth outcomes. Diagnosis of malaria, during pregnancy, is complicated by the absence or low parasite densities in peripheral blood. Diagnostic methods, other than microscopy, are needed for detection of placental malaria. Therefore, the diagnostic accuracy of rapid diagnostic tests (RDTs), detecting antigen, and molecular techniques (PCR), detecting DNA, for the diagnosis of Plasmodium infections in pregnancy was systematically reviewed. Methods MEDLINE, EMBASE and Web of Science were searched for studies assessing the diagnostic accuracy of RDTs, PCR, microscopy of peripheral and placental blood and placental histology for the detection of malaria infection (all species) in pregnant women. Results The results of 49 studies were analysed in metandi (Stata), of which the majority described P. falciparum infections. Although both placental and peripheral blood microscopy cannot reliably replace histology as a reference standard for placental P. falciparum infection, many studies compared RDTs and PCR to these tests. The proportion of microscopy positives in placental blood (sensitivity) detected by peripheral blood microscopy, RDTs and PCR are respectively 72% [95% CI 62-80], 81% [95% CI 55-93] and 94% [95% CI 86-98]. The proportion of placental blood microscopy negative women that were negative in peripheral blood microscopy, RDTs and PCR (specificity) are 98% [95% CI 95-99], 94% [95% CI 76-99] and 77% [95% CI 71-82]. Based on the current data, it was not possible to determine if the false positives in RDTs and PCR are caused by sequestered parasites in the placenta that are not detected by placental microscopy. Conclusion The findings suggest that RDTs and PCR may have good performance characteristics to serve as alternatives for the diagnosis of malaria in pregnancy, besides any other limitations and practical considerations concerning the use of these tests. Nevertheless, more studies with placental histology as reference test are urgently required to reliably determine the accuracy of RDTs and PCR for the diagnosis of placental malaria. P. vivax-infections have been neglected in diagnostic test accuracy studies of malaria in pregnancy. PMID:22035448

Diagnostic accuracy of magnetic resonance imaging techniques for treatment response evaluation in patients with high-grade glioma, a systematic review and meta-analysis.

PubMed

van Dijken, Bart R J; van Laar, Peter Jan; Holtman, Gea A; van der Hoorn, Anouk

2017-10-01

Treatment response assessment in high-grade gliomas uses contrast enhanced T1-weighted MRI, but is unreliable. Novel advanced MRI techniques have been studied, but the accuracy is not well known. Therefore, we performed a systematic meta-analysis to assess the diagnostic accuracy of anatomical and advanced MRI for treatment response in high-grade gliomas. Databases were searched systematically. Study selection and data extraction were done by two authors independently. Meta-analysis was performed using a bivariate random effects model when ≥5 studies were included. Anatomical MRI (five studies, 166 patients) showed a pooled sensitivity and specificity of 68% (95%CI 51-81) and 77% (45-93), respectively. Pooled apparent diffusion coefficients (seven studies, 204 patients) demonstrated a sensitivity of 71% (60-80) and specificity of 87% (77-93). DSC-perfusion (18 studies, 708 patients) sensitivity was 87% (82-91) with a specificity of 86% (77-91). DCE-perfusion (five studies, 207 patients) sensitivity was 92% (73-98) and specificity was 85% (76-92). The sensitivity of spectroscopy (nine studies, 203 patients) was 91% (79-97) and specificity was 95% (65-99). Advanced techniques showed higher diagnostic accuracy than anatomical MRI, the highest for spectroscopy, supporting the use in treatment response assessment in high-grade gliomas. • Treatment response assessment in high-grade gliomas with anatomical MRI is unreliable • Novel advanced MRI techniques have been studied, but diagnostic accuracy is unknown • Meta-analysis demonstrates that advanced MRI showed higher diagnostic accuracy than anatomical MRI • Highest diagnostic accuracy for spectroscopy and perfusion MRI • Supports the incorporation of advanced MRI in high-grade glioma treatment response assessment.

Value of endoscopic ultrasound guided fine needle aspiration biopsy in the diagnosis of solid pancreatic masses

PubMed Central

Voss, M; Hammel, P; Molas, G; Palazzo, L; Dancour, A; O'Toole, D; Terris, B; Degott, C; Bernades, P; Ruszniewski, P

2000-01-01

AIM—To assess the feasibility and diagnostic accuracy of endoscopic ultrasound guided fine needle biopsy (EUS-FNAB) in patients with solid pancreatic masses.
METHODS—Ninety nine consecutive patients with pancreatic masses were studied. Histological findings obtained by EUS-FNAB were compared with the final diagnosis assessed by surgery, biopsy of other tumour site or at postmortem examination, or by using a combination of clinical course, imaging features, and tumour markers.
RESULTS—EUS-FNAB was feasible in 90 patients (adenocarcinomas, n = 59; neuroendocrine tumours, n = 15; various neoplasms, n = 6; pancreatitis, n = 10), and analysable material was obtained in 73. Tumour size (⩾ or < 25 mm in diameter) did not influence the ability to obtain informative biopsy samples. Diagnostic accuracy was 74.4% (adenocarcinomas, 81.4%; neuroendocrine tumours, 46.7%; other lesions, 75%; p<0.02). Overall, the diagnostic yield in all 99 patients was 68%. Successful biopsies were performed in six patients with portal hypertension. Minor complications (moderate bleeding or pain) occurred in 5% of cases.
CONCLUSIONS—EUS-FNAB is a useful and safe method for the investigation of pancreatic masses, with a high feasibility rate even when lesions are small. Overall diagnostic accuracy of EUS-FNAB seems to depend on the tumour type.


Keywords: pancreas; tumour; endoscopic ultrasound; fine needle aspiration biopsy PMID:10644320

Applying Amide Proton Transfer MR Imaging to Hybrid Brain PET/MR: Concordance with Gadolinium Enhancement and Added Value to [18F]FDG PET.

PubMed

Sun, Hongzan; Xin, Jun; Zhou, Jinyuan; Lu, Zaiming; Guo, Qiyong

2018-06-01

The purpose of this study is to evaluate the diagnostic concordance and metric correlations of amide proton transfer (APT) imaging with gadolinium-enhanced magnetic resonance imaging (MRI) and 2-deoxy-2-[ 18 F-]fluoro-D-glucose ([ 18 F]FDG) positron emission tomography (PET), using hybrid brain PET/MRI. Twenty-one subjects underwent brain gadolinium-enhanced [ 18 F]FDG PET/MRI prospectively. Imaging accuracy was compared between unenhanced MRI, MRI with enhancement, APT-weighted (APTW) images, and PET based on six diagnostic criteria. Among tumors, the McNemar test was further used for concordance assessment between gadolinium-enhanced imaging, APT imaging, and [ 18 F]FDG PET. As well, the relation of metrics between APT imaging and PET was analyzed by the Pearson correlation analysis. APT imaging and gadolinium-enhanced MRI showed superior and similar diagnostic accuracy. APTW signal intensity and gadolinium enhancement were concordant in 19 tumors (100 %), while high [ 18 F]FDG avidity was shown in only 12 (63.2 %). For the metrics from APT imaging and PET, there was significant correlation for 13 hypermetabolic tumors (P < 0.05) and no correlation for the remaining six [ 18 F]FDG-avid tumors. APT imaging can be used to increase diagnostic accuracy with no need to administer gadolinium chelates. APT imaging may provide an added value to [ 18 F]FDG PET in the evaluation of tumor metabolic activity during brain PET/MR studies.

Estimation of an accuracy index of a diagnostic biomarker when the reference biomarker is continuous and measured with error.

PubMed

Wu, Mixia; Zhang, Dianchen; Liu, Aiyi

2016-01-01

New biomarkers continue to be developed for the purpose of diagnosis, and their diagnostic performances are typically compared with an existing reference biomarker used for the same purpose. Considerable amounts of research have focused on receiver operating characteristic curves analysis when the reference biomarker is dichotomous. In the situation where the reference biomarker is measured on a continuous scale and dichotomization is not practically appealing, an index was proposed in the literature to measure the accuracy of a continuous biomarker, which is essentially a linear function of the popular Kendall's tau. We consider the issue of estimating such an accuracy index when the continuous reference biomarker is measured with errors. We first investigate the impact of measurement errors on the accuracy index, and then propose methods to correct for the bias due to measurement errors. Simulation results show the effectiveness of the proposed estimator in reducing biases. The methods are exemplified with hemoglobin A1c measurements obtained from both the central lab and a local lab to evaluate the accuracy of the mean data obtained from the metered blood glucose monitoring against the centrally measured hemoglobin A1c from a behavioral intervention study for families of youth with type 1 diabetes.

Diagnostic accuracy of liver fibrosis based on red cell distribution width (RDW) to platelet ratio with fibroscan in chronic hepatitis B

NASA Astrophysics Data System (ADS)

Sembiring, J.; Jones, F.

2018-03-01

Red cell Distribution Width (RDW) and platelet ratio (RPR) can predict liver fibrosis and cirrhosis in chronic hepatitis B with relatively high accuracy. RPR was superior to other non-invasive methods to predict liver fibrosis, such as AST and ALT ratio, AST and platelet ratio Index and FIB-4. The aim of this study was to assess diagnostic accuracy liver fibrosis by using RDW and platelets ratio in chronic hepatitis B patients based on compared with Fibroscan. This cross-sectional study was conducted at Adam Malik Hospital from January-June 2015. We examine 34 patients hepatitis B chronic, screen RDW, platelet, and fibroscan. Data were statistically analyzed. The result RPR with ROC procedure has an accuracy of 72.3% (95% CI: 84.1% - 97%). In this study, the RPR had a moderate ability to predict fibrosis degree (p = 0.029 with AUC> 70%). The cutoff value RPR was 0.0591, sensitivity and spesificity were 71.4% and 60%, Positive Prediction Value (PPV) was 55.6% and Negative Predictions Value (NPV) was 75%, positive likelihood ratio was 1.79 and negative likelihood ratio was 0.48. RPR have the ability to predict the degree of liver fibrosis in chronic hepatitis B patients with moderate accuracy.

Effects of optical diagnostic techniques on the accuracy of laminar flame speeds measured from Bunsen flames: OH* chemiluminescence, OH-PLIF and acetone/kerosene-PLIF

NASA Astrophysics Data System (ADS)

Wu, Yi; Modica, Vincent; Yu, Xilong; Li, Fei; Grisch, Frédéric

2018-01-01

The effects of optical diagnostic techniques on the accuracy of laminar flame speed measured from Bunsen flames were investigated. Laminar flame speed measurements were conducted for different fuel/air mixtures including CH4/air, acetone/air and kerosene (Jet A-1)/air in applying different optical diagnostic techniques, i.e. OH* chemiluminescence, OH-PLIF and acetone/kerosene-PLIF. It is found that the OH* chemiluminescence imaging technique cannot directly derive the location of the outer edge of the fresh gases and it is necessary to correct the position of the OH* peak to guarantee the accuracy of the measurements. OH-PLIF and acetone/kerosene-PLIF respectively are able to measure the disappearance of the fresh gas contour and the appearance of the reaction zone. It shows that the aromatic-PLIF technique gives similar laminar flame speed values when compared with those obtained from corrected OH* chemiluminescence images. However, discrepancies were observed between the OH-PLIF and the aromatic-PLIF techniques, in that OH-PLIF slightly underestimates laminar flame speeds by up to 5%. The difference between the flame contours obtained from different optical techniques are further analysed and illustrated with 1D flame structure simulation using detailed kinetic mechanisms.

Office hysteroscopic-guided selective tubal chromopertubation: acceptability, feasibility and diagnostic accuracy of this new diagnostic non-invasive technique in infertile women.

PubMed

Carta, Gaspare; Palermo, Patrizia; Pasquale, Chiara; Conte, Valeria; Pulcinella, Ruggero; Necozione, Stefano; Cofini, Vincenza; Patacchiola, Felice

2018-06-01

The aim of this study was to evaluate accuracy, tolerability and side effects of office hysteroscopic-guided chromoperturbations in infertile women without anaesthesia. Forty-nine infertile women underwent the procedure to evaluate tubal patency and the uterine cavity. Women with unilateral or bilateral tubal stenosis at hysteroscopy with chromoperturbation, and women with bilateral tubal patency who did not conceive during the period of six months, underwent laparoscopy with chromoperturbation. The results obtained from hysteroscopy and laparoscopy in the assessment of tubal patency were compared. Sensitivity, specificity, accuracy, positive-predictive value and negative-predictive value were used to describe diagnostic performance. Pain and tolerance were assessed during procedure using a visual analogue scale (VAS). Side effects or late complications and pregnancy rate were also recorded three and six months after the procedure. The specificity was 87.8% (95% CI: 73.80-95.90), sensitivity was 85.7% (95% CI 57.20-98.20), positive and negative predictive values were 70.6% (95% CI: 44.00-89) and 94.7% (95% CI: 82.30-99.40), respectively. Pregnancy rate (PR) within six months after performance of hysteroscopy with chromoperturbation was 27%. Office hysteroscopy-guided selective chromoperturbation in infertile patients is a valid technique to evaluate tubal patency and uterine cavity.

Follow-up of coronary artery bypass graft patency: diagnostic efficiency of high-pitch dual-source 256-slice MDCT findings.

PubMed

Yuceler, Zeyneb; Kantarci, Mecit; Yuce, Ihsan; Kizrak, Yesim; Bayraktutan, Ummugulsum; Ogul, Hayri; Kiris, Adem; Celik, Omer; Pirimoglu, Berhan; Genc, Berhan; Gundogdu, Fuat

2014-01-01

Our aim was to evaluate the diagnostic accuracy of 256-slice, high-pitch mode multidetector computed tomography (MDCT) for coronary artery bypass graft (CABG) patency. Eighty-eight patients underwent 256-slice MDCT angiography to evaluate their graft patency after CABG surgery using a prospectively synchronized electrocardiogram in the high-pitch spiral acquisition mode. Effective radiation doses were calculated. We investigated the diagnostic accuracy of high-pitch, low-dose, prospective, electrocardiogram-triggering, dual-source MDCT for CABG patency compared with catheter coronary angiography imaging findings. A total of 215 grafts and 645 vessel segments were analyzed. All graft segments had diagnostic image quality. The proximal and middle graft segments had significantly (P < 0.05) better mean image quality scores (1.18 ± 0.4) than the distal segments (1.31 ± 0.5). Using catheter coronary angiography as the reference standard, high-pitch MDCT had the following sensitivity, specificity, positive predictive value, and negative predictive value of per-segment analysis for detecting graft patency: 97.1%, 99.6%, 94.4%, and 99.8%, respectively. In conclusion, MDCT can be used noninvasively with a lower radiation dose for the assessment of restenosis in CABG patients.

Comparative effectiveness of i-SCAN™ and high-definition white light characterizing small colonic polyps.

PubMed

Chan, Johanna L; Lin, Li; Feiler, Michael; Wolf, Andrew I; Cardona, Diana M; Gellad, Ziad F

2012-11-07

To evaluate accuracy of in vivo diagnosis of adenomatous vs non-adenomatous polyps using i-SCAN digital chromoendoscopy compared with high-definition white light. This is a single-center comparative effectiveness pilot study. Polyps (n = 103) from 75 average-risk adult outpatients undergoing screening or surveillance colonoscopy between December 1, 2010 and April 1, 2011 were evaluated by two participating endoscopists in an academic outpatient endoscopy center. Polyps were evaluated both with high-definition white light and with i-SCAN to make an in vivo prediction of adenomatous vs non-adenomatous pathology. We determined diagnostic characteristics of i-SCAN and high-definition white light, including sensitivity, specificity, and accuracy, with regards to identifying adenomatous vs non-adenomatous polyps. Histopathologic diagnosis was the gold standard comparison. One hundred and three small polyps, detected from forty-three patients, were included in the analysis. The average size of the polyps evaluated in the analysis was 3.7 mm (SD 1.3 mm, range 2 mm to 8 mm). Formal histopathology revealed that 54/103 (52.4%) were adenomas, 26/103 (25.2%) were hyperplastic, and 23/103 (22.3%) were other diagnoses include "lymphoid aggregates", "non-specific colitis," and "no pathologic diagnosis." Overall, the combined accuracy of endoscopists for predicting adenomas was identical between i-SCAN (71.8%, 95%CI: 62.1%-80.3%) and high-definition white light (71.8%, 95%CI: 62.1%-80.3%). However, the accuracy of each endoscopist differed substantially, where endoscopist A demonstrated 63.0% overall accuracy (95%CI: 50.9%-74.0%) as compared with endoscopist B demonstrating 93.3% overall accuracy (95%CI: 77.9%-99.2%), irrespective of imaging modality. Neither endoscopist demonstrated a significant learning effect with i-SCAN during the study. Though endoscopist A increased accuracy using i-SCAN from 59% (95%CI: 42.1%-74.4%) in the first half to 67.6% (95%CI: 49.5%-82.6%) in the second half, and endoscopist B decreased accuracy using i-SCAN from 100% (95%CI: 80.5%-100.0%) in the first half to 84.6% (95%CI: 54.6%-98.1%) in the second half, neither of these differences were statistically significant. i-SCAN and high-definition white light had similar efficacy predicting polyp histology. Endoscopist training likely plays a critical role in diagnostic test characteristics and deserves further study.

Meta-analysis of diagnostic accuracy studies in mental health

PubMed Central

Takwoingi, Yemisi; Riley, Richard D; Deeks, Jonathan J

2015-01-01

Objectives To explain methods for data synthesis of evidence from diagnostic test accuracy (DTA) studies, and to illustrate different types of analyses that may be performed in a DTA systematic review. Methods We described properties of meta-analytic methods for quantitative synthesis of evidence. We used a DTA review comparing the accuracy of three screening questionnaires for bipolar disorder to illustrate application of the methods for each type of analysis. Results The discriminatory ability of a test is commonly expressed in terms of sensitivity (proportion of those with the condition who test positive) and specificity (proportion of those without the condition who test negative). There is a trade-off between sensitivity and specificity, as an increasing threshold for defining test positivity will decrease sensitivity and increase specificity. Methods recommended for meta-analysis of DTA studies --such as the bivariate or hierarchical summary receiver operating characteristic (HSROC) model --jointly summarise sensitivity and specificity while taking into account this threshold effect, as well as allowing for between study differences in test performance beyond what would be expected by chance. The bivariate model focuses on estimation of a summary sensitivity and specificity at a common threshold while the HSROC model focuses on the estimation of a summary curve from studies that have used different thresholds. Conclusions Meta-analyses of diagnostic accuracy studies can provide answers to important clinical questions. We hope this article will provide clinicians with sufficient understanding of the terminology and methods to aid interpretation of systematic reviews and facilitate better patient care. PMID:26446042

Gliomas: Application of Cumulative Histogram Analysis of Normalized Cerebral Blood Volume on 3 T MRI to Tumor Grading

PubMed Central

Kim, Hyungjin; Choi, Seung Hong; Kim, Ji-Hoon; Ryoo, Inseon; Kim, Soo Chin; Yeom, Jeong A.; Shin, Hwaseon; Jung, Seung Chai; Lee, A. Leum; Yun, Tae Jin; Park, Chul-Kee; Sohn, Chul-Ho; Park, Sung-Hye

2013-01-01

Background Glioma grading assumes significant importance in that low- and high-grade gliomas display different prognoses and are treated with dissimilar therapeutic strategies. The objective of our study was to retrospectively assess the usefulness of a cumulative normalized cerebral blood volume (nCBV) histogram for glioma grading based on 3 T MRI. Methods From February 2010 to April 2012, 63 patients with astrocytic tumors underwent 3 T MRI with dynamic susceptibility contrast perfusion-weighted imaging. Regions of interest containing the entire tumor volume were drawn on every section of the co-registered relative CBV (rCBV) maps and T2-weighted images. The percentile values from the cumulative nCBV histograms and the other histogram parameters were correlated with tumor grades. Cochran’s Q test and the McNemar test were used to compare the diagnostic accuracies of the histogram parameters after the receiver operating characteristic curve analysis. Using the parameter offering the highest diagnostic accuracy, a validation process was performed with an independent test set of nine patients. Results The 99th percentile of the cumulative nCBV histogram (nCBV C99), mean and peak height differed significantly between low- and high-grade gliomas (P = <0.001, 0.014 and <0.001, respectively) and between grade III and IV gliomas (P = <0.001, 0.001 and <0.001, respectively). The diagnostic accuracy of nCBV C99 was significantly higher than that of the mean nCBV (P = 0.016) in distinguishing high- from low-grade gliomas and was comparable to that of the peak height (P = 1.000). Validation using the two cutoff values of nCBV C99 achieved a diagnostic accuracy of 66.7% (6/9) for the separation of all three glioma grades. Conclusion Cumulative histogram analysis of nCBV using 3 T MRI can be a useful method for preoperative glioma grading. The nCBV C99 value is helpful in distinguishing high- from low-grade gliomas and grade IV from III gliomas. PMID:23704910

[The value of bedside lung ultrasound in emergency-plus protocol for the assessment of lung consolidation and atelectasis in critical patients].

PubMed

Wang, Xiao-ting; Liu, Da-wei; Zhang, Hong-min; He, Huai-wu; Liu, Ye; Chai, Wen-zhao; Du, Wei

2012-12-01

To investigate the effect of the bedside lung ultrasound in emergency(BLUE)-plus lung ultrasound protocol on lung consolidation and atelectasis of critical patients. All patients who need to receive mechanical ventilation for more than 48 hours in ICU from June 2010 to December 2011 in Peking Union Medical College Hospital were included in the study. BLUE-plus and BLUE lung ultrasound, bedside X-ray, lung CT examination were performed on all patients at the same time. The condition of lung consolidation and atelectasis discovered by BLUE-plus lung ultrasound protocol was recorded and compared with bedside X-ray or lung CT. The difference in assessment of lung consolidation and atelectasis between BLUE-plus lung ultrasound protocol and BLUE protocol was compared. A total of 78 patients were finally enrolled in the study. The lung CT found 70 cases (89.74%) had different degrees of lung consolidation and atelectasis. The sensitivity, specificity and diagnostic accuracy of lung consolidation and atelectasis by the bedside chest X-ray were 31.29%, 75.00% and 38.46%, respectively. BLUE-plus lung ultrasound protocol found 68 cases with lung consolidation and atelectasis, and its sensitivity, specificity, and diagnostic accuracy were 95.71%, 87.50% and 94.87%, respectively, which were significantly higher than those of lung CT. BLUE protocol found 48 cases of lung consolidation and atelectasis, and its sensitivity, specificity, and diagnostic accuracy were 65.71%, 75.00% and 66.67%, respectively. The position of lung consolidation and atelectasis which hadn't been found by BLUE protocol was mainly proved to be located in the basement of lung by lung CT. The incidence of lung consolidation and atelectasis in critical patients who received mechanical ventilation is high. The BLUE-plus lung ultrasound protocol has a relatively higher sensitivity, specificity and diagnostic accuracy for consolidation and atelectasis, which can find majority of consolidation and atelectasis. As BLUE-plus lung ultrasound is a bedside noninvasive method allowing immediate assessment of most lung consolidation and atelectasis, it will be likely the alternative of the CT and play a key role in assessment of lung consolidation and atelectasis.

A BMI-adjusted ultra-low-dose CT angiography protocol for the peripheral arteries-Image quality, diagnostic accuracy and radiation exposure.

PubMed

Schreiner, Markus M; Platzgummer, Hannes; Unterhumer, Sylvia; Weber, Michael; Mistelbauer, Gabriel; Loewe, Christian; Schernthaner, Ruediger E

2017-08-01

To investigate radiation exposure, objective image quality, and the diagnostic accuracy of a BMI-adjusted ultra-low-dose CT angiography (CTA) protocol for the assessment of peripheral arterial disease (PAD), with digital subtraction angiography (DSA) as the standard of reference. In this prospective, IRB-approved study, 40 PAD patients (30 male, mean age 72 years) underwent CTA on a dual-source CT scanner at 80kV tube voltage. The reference amplitude for tube current modulation was personalized based on the body mass index (BMI) with 120 mAs for [BMI≤25] or 150 mAs for [2570%) was assessed by two readers independently and compared to subsequent DSA. Radiation exposure was assessed with the computed tomography dose index (CTDIvol) and the dosis-length product (DLP). Objective image quality was assessed via contrast- and signal-to-noise ratio (CNR and SNR) measurements. Radiation exposure and image quality were compared between the BMI groups and between the BMI-adjusted ultra-low-dose protocol and the low-dose institutional standard protocol (ISP). The BMI-adjusted ultra-low-dose protocol reached high diagnostic accuracy values of 94% for Reader 1 and 93% for Reader 2. Moreover, in comparison to the ISP, it showed significantly (p<0.001) lower CTDIvol (1.97±0.55mGy vs. 4.18±0.62 mGy) and DLP (256±81mGy x cm vs. 544±83mGy x cm) but similar image quality (p=0.37 for CNR). Furthermore, image quality was similar between BMI groups (p=0.86 for CNR). A CT protocol that incorporates low kV settings with a personalized (BMI-adjusted) reference amplitude for tube current modulation and iterative reconstruction enables very low radiation exposure CTA, while maintaining good image quality and high diagnostic accuracy in the assessment of PAD. Copyright © 2017 Elsevier B.V. All rights reserved.

Diagnostic Accuracy and Clinical Implications of Translabial Ultrasound for the Assessment of Levator Ani Defects and Levator Ani Biometry in Women With Pelvic Organ Prolapse: A Systematic Review.

PubMed

Notten, Kim J B; Vergeldt, Tineke F M; van Kuijk, Sander M J; Weemhoff, Mirjam; Roovers, Jan-Paul W R

The aim of this study was to assess the diagnostic accuracy and clinical implications of translabial 3-dimensional (3D) ultrasound for the assessment of levator ani defects and biometry in women with pelvic organ prolapse (POP). We performed a systematic literature search through computerized databases including MEDLINE (via PubMed), EMBASE (via OvidSP), and the Cochrane Library using both medical subject headings and text terms from January 1, 2003, to December 25, 2015.We included articles that reported on POP status and diagnostic accuracy measurements with translabial 3D ultrasound or transperineal ultrasound for the detection of levator ani defects or for measuring pelvic floor biometry, that is, levator ani hiatus, or reported on the clinical relevance of using translabial 3D ultrasound for levator ani defects or measuring pelvic floor biometry in women with POP. Thirty-one articles were selected in accordance with parts of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines that can be applied to studies of diagnostic accuracy. Twenty-two articles (71%) are coauthored by 1 expert in this field. Detecting levator ani defects with translabial 3D ultrasound compared with magnetic resonance imaging showed a moderate to good agreement, whereas measuring hiatal biometry on translabial 3D ultrasound compared with magnetic resonance imaging showed a moderate to very good agreement.The interobserver agreement for diagnosing levator ani defects and measuring the levator hiatal area showed a moderate to very good agreement. Furthermore, levator ani defects increase the risk of cystocele and uterine prolapse, and levator ani defects are associated with recurrent POP.Finally, a larger hiatus was associated with POP and recurrent POP. Translabial 3D ultrasound is reproducible for diagnosing levator ani defects and ballooning hiatus. Both levator ani defects and a larger hiatal area are, in a selected population of patients with pelvic floor dysfunction, associated with POP and recurrent POP. More research is needed concerning external validation because most data in this article are coauthored by 1 expert in this field.

Comparing Computer-Adaptive and Curriculum-Based Measurement Methods of Assessment

ERIC Educational Resources Information Center

Shapiro, Edward S.; Gebhardt, Sarah N.

2012-01-01

This article reported the concurrent, predictive, and diagnostic accuracy of a computer-adaptive test (CAT) and curriculum-based measurements (CBM; both computation and concepts/application measures) for universal screening in mathematics among students in first through fourth grade. Correlational analyses indicated moderate to strong…

ROC curve analyses of eyewitness identification decisions: An analysis of the recent debate.

PubMed

Rotello, Caren M; Chen, Tina

2016-01-01

How should the accuracy of eyewitness identification decisions be measured, so that best practices for identification can be determined? This fundamental question is under intense debate. One side advocates for continued use of a traditional measure of identification accuracy, known as the diagnosticity ratio , whereas the other side argues that receiver operating characteristic curves (ROCs) should be used instead because diagnosticity is confounded with response bias. Diagnosticity proponents have offered several criticisms of ROCs, which we show are either false or irrelevant to the assessment of eyewitness accuracy. We also show that, like diagnosticity, Bayesian measures of identification accuracy confound response bias with witnesses' ability to discriminate guilty from innocent suspects. ROCs are an essential tool for distinguishing memory-based processes from decisional aspects of a response; simulations of different possible identification tasks and response strategies show that they offer important constraints on theory development.

Diagnostic accuracy of scapular physical examination tests for shoulder disorders: a systematic review.

PubMed

Wright, Alexis A; Wassinger, Craig A; Frank, Mason; Michener, Lori A; Hegedus, Eric J

2013-09-01

To systematically review and critique the evidence regarding the diagnostic accuracy of physical examination tests for the scapula in patients with shoulder disorders. A systematic, computerised literature search of PubMED, EMBASE, CINAHL and the Cochrane Library databases (from database inception through January 2012) using keywords related to diagnostic accuracy of physical examination tests of the scapula. The Quality Assessment of Diagnostic Accuracy Studies tool was used to critique the quality of each paper. Eight articles met the inclusion criteria; three were considered to be of high quality. Of the three high-quality studies, two were in reference to a 'diagnosis' of shoulder pain. Only one high-quality article referenced specific shoulder pathology of acromioclavicular dislocation with reported sensitivity of 71% and 41% for the scapular dyskinesis and SICK scapula test, respectively. Overall, no physical examination test of the scapula was found to be useful in differentially diagnosing pathologies of the shoulder.

The impact of a computerised test of attention and activity (QbTest) on diagnostic decision-making in children and young people with suspected attention deficit hyperactivity disorder: single-blind randomised controlled trial.

PubMed

Hollis, Chris; Hall, Charlotte L; Guo, Boliang; James, Marilyn; Boadu, Janet; Groom, Madeleine J; Brown, Nikki; Kaylor-Hughes, Catherine; Moldavsky, Maria; Valentine, Althea Z; Walker, Gemma M; Daley, David; Sayal, Kapil; Morriss, Richard

2018-04-26

Diagnosis of attention deficit hyperactivity disorder (ADHD) relies on subjective methods which can lead to diagnostic uncertainty and delay. This trial evaluated the impact of providing a computerised test of attention and activity (QbTest) report on the speed and accuracy of diagnostic decision-making in children with suspected ADHD. Randomised, parallel, single-blind controlled trial in mental health and community paediatric clinics in England. Participants were 6-17 years-old and referred for ADHD diagnostic assessment; all underwent assessment-as-usual, plus QbTest. Participants and their clinician were randomised to either receive the QbTest report immediately (QbOpen group) or the report was withheld (QbBlind group). The primary outcome was number of consultations until a diagnostic decision confirming/excluding ADHD within 6-months from baseline. Health economic cost-effectiveness and cost utility analysis was conducted. Assessing QbTest Utility in ADHD: A Randomised Controlled Trial was registered at ClinicalTrials.gov (https://clinicaltrials.gov/ct2/show/NCT02209116). One hundred and thirty-two participants were randomised to QbOpen group (123 analysed) and 135 to QbBlind group (127 analysed). Clinicians with access to the QbTest report (QbOpen) were more likely to reach a diagnostic decision about ADHD (hazard ratio 1.44, 95% CI 1.04-2.01). At 6-months, 76% of those with a QbTest report had received a diagnostic decision, compared with 50% without. QbTest reduced appointment length by 15% (time ratio 0.85, 95% CI 0.77-0.93), increased clinicians' confidence in their diagnostic decisions (odds ratio 1.77, 95% CI 1.09-2.89) and doubled the likelihood of excluding ADHD. There was no difference in diagnostic accuracy. Health economic analysis showed a position of strict dominance; however, cost savings were small suggesting that the impact of providing the QbTest report within this trial can best be viewed as 'cost neutral'. QbTest may increase the efficiency of ADHD assessment pathway allowing greater patient throughput with clinicians reaching diagnostic decisions faster without compromising diagnostic accuracy. © 2018 The Authors. Journal of Child Psychology and Psychiatry published by John Wiley & Sons Ltd on behalf of Association for Child and Adolescent Mental Health.

Using meta-analysis to inform the design of subsequent studies of diagnostic test accuracy.

PubMed

Hinchliffe, Sally R; Crowther, Michael J; Phillips, Robert S; Sutton, Alex J

2013-06-01

An individual diagnostic accuracy study rarely provides enough information to make conclusive recommendations about the accuracy of a diagnostic test; particularly when the study is small. Meta-analysis methods provide a way of combining information from multiple studies, reducing uncertainty in the result and hopefully providing substantial evidence to underpin reliable clinical decision-making. Very few investigators consider any sample size calculations when designing a new diagnostic accuracy study. However, it is important to consider the number of subjects in a new study in order to achieve a precise measure of accuracy. Sutton et al. have suggested previously that when designing a new therapeutic trial, it could be more beneficial to consider the power of the updated meta-analysis including the new trial rather than of the new trial itself. The methodology involves simulating new studies for a range of sample sizes and estimating the power of the updated meta-analysis with each new study added. Plotting the power values against the range of sample sizes allows the clinician to make an informed decision about the sample size of a new trial. This paper extends this approach from the trial setting and applies it to diagnostic accuracy studies. Several meta-analytic models are considered including bivariate random effects meta-analysis that models the correlation between sensitivity and specificity. Copyright © 2012 John Wiley & Sons, Ltd. Copyright © 2012 John Wiley & Sons, Ltd.

Diagnostic performance of a Lattice Boltzmann-based method for CT-based fractional flow reserve.

PubMed

Giannopoulos, Andreas A; Tang, Anji; Ge, Yin; Cheezum, Michael K; Steigner, Michael L; Fujimoto, Shinichiro; Kumamaru, Kanako K; Chiappino, Dante; Della Latta, Daniele; Berti, Sergio; Chiappino, Sara; Rybicki, Frank J; Melchionna, Simone; Mitsouras, Dimitrios

2018-02-20

Fractional flow reserve (FFR) estimated from coronary computed tomography angiography (CT-FFR) offers non-invasive detection of lesion-specific ischaemia. We aimed to develop and validate a fast CT-FFR algorithm utilising the Lattice Boltzmann method for blood flow simulation (LBM CT-FFR). Sixty-four patients with clinically indicated CTA and invasive FFR measurement from three institutions were retrospectively analysed. CT-FFR was performed using an onsite tool interfacing with a commercial Lattice Boltzmann fluid dynamics cloud-based platform. Diagnostic accuracy of LBM CT-FFR ≤0.8 and percent diameter stenosis >50% by CTA to detect invasive FFR ≤0.8 were compared using area under the receiver operating characteristic curve (AUC). Sixty patients successfully underwent LBM CT-FFR analysis; 29 of 73 lesions in 69 vessels had invasive FFR ≤0.8. Total time to perform LBM CT-FFR was 40±10 min. Compared to invasive FFR, LBM CT-FFR had good correlation (r=0.64), small bias (0.009) and good limits of agreement (-0.223 to 0.206). The AUC of LBM CT-FFR (AUC=0.894, 95% confidence interval [CI]: 0.792-0.996) was significantly higher than CTA (AUC=0.685, 95% CI: 0.576-0.794) to detect FFR ≤0.8 (p=0.0021). Per-lesion specificity, sensitivity, and accuracy of LBM CT-FFR were 97.7%, 79.3%, and 90.4%, respectively. LBM CT-FFR has very good diagnostic accuracy to detect lesion-specific ischaemia (FFR ≤0.8) and can be performed in less than one hour.

Inaccuracy of Wolff-Parkinson-white accessory pathway localization algorithms in children and patients with congenital heart defects.

PubMed

Bar-Cohen, Yaniv; Khairy, Paul; Morwood, James; Alexander, Mark E; Cecchin, Frank; Berul, Charles I

2006-07-01

ECG algorithms used to localize accessory pathways (AP) in patients with Wolff-Parkinson-White (WPW) syndrome have been validated in adults, but less is known of their use in children, especially in patients with congenital heart disease (CHD). We hypothesize that these algorithms have low diagnostic accuracy in children and even lower in those with CHD. Pre-excited ECGs in 43 patients with WPW and CHD (median age 5.4 years [0.9-32 years]) were evaluated and compared to 43 consecutive WPW control patients without CHD (median age 14.5 years [1.8-18 years]). Two blinded observers predicted AP location using 2 adult and 1 pediatric WPW algorithms, and a third blinded observer served as a tiebreaker. Predicted locations were compared with ablation-verified AP location to identify (a) exact match for AP location and (b) match for laterality (left-sided vs right-sided AP). In control children, adult algorithms were accurate in only 56% and 60%, while the pediatric algorithm was correct in 77%. In 19 patients with Ebstein's anomaly, diagnostic accuracy was similar to controls with at times an even better ability to predict laterality. In non-Ebstein's CHD, however, the algorithms were markedly worse (29% for the adult algorithms and 42% for the pediatric algorithms). A relatively large degree of interobserver variability was seen (kappa values from 0.30 to 0.58). Adult localization algorithms have poor diagnostic accuracy in young patients with and without CHD. Both adult and pediatric algorithms are particularly misleading in non-Ebstein's CHD patients and should be interpreted with caution.

Brain 18F-FDG PET in the diagnosis of neurodegenerative dementias: comparison with perfusion SPECT and with clinical evaluations lacking nuclear imaging.

PubMed

Silverman, Daniel H S

2004-04-01

The clinical identification and differential diagnosis of dementias is especially challenging in the early stages, but the need for early, accurate diagnosis has become more important, now that several medications for the treatment of mild to moderate Alzheimer's disease (AD) are available. Many neurodegenerative diseases produce significant brain-function alterations detectable with PET or SPECT even when structural images with CT or MRI reveal no specific abnormalities. (18)F-FDG PET images of AD demonstrate focally decreased cerebral metabolism involving especially the posterior cingulate and neocortical association cortices, while largely sparing the basal ganglia, thalamus, cerebellum, and cortex mediating primary sensory and motor functions. Assessment of the precise diagnostic accuracy of PET had until recently been hindered by the paucity of data on diagnoses made using PET and confirmed by definitive histopathologic examination. In the past few years, however, studies comparing neuropathologic examination with PET have established reliable and consistent accuracy for diagnostic evaluations using PET-accuracies substantially exceeding those of comparable studies of the diagnostic value of SPECT or of both modalities assessed side by side, or of clinical evaluations done without nuclear imaging. Similar data are emerging concerning the prognostic value of (18)F-FDG PET. Improvements in the ability of PET to identify very early changes associated with AD and other neurodegenerative dementias are currently outpacing improvements in therapeutic options, but with advances in potential preventive and disease-modifying treatments appearing imminent, early detection and diagnosis will play an increasing role in the management of dementing illness.

Instantaneous wave-free ratio as an alternative to fractional flow reserve in assessment of moderate coronary stenoses: A meta-analysis of diagnostic accuracy studies.

PubMed

Maini, Rohit; Moscona, John; Katigbak, Paul; Fernandez, Camilo; Sidhu, Gursukhmandeep; Saleh, Qusai; Irimpen, Anand; Samson, Rohan; LeJemtel, Thierry

2017-12-27

Fractional flow reserve (FFR) remains underutilized due to practical concerns related to the need for hyperemic agents. These concerns have prompted the study of instantaneous wave-free ratio (iFR), a vasodilator-free index of coronary stenosis. Non-inferior cardiovascular outcomes have been demonstrated in two recent randomized clinic trials. We performed this meta-analysis to provide a necessary update of the diagnostic accuracy of iFR referenced to FFR based on the addition of eight more recent studies and 3727 more lesions. We searched the PubMed, EMBASE, Central, ProQuest, and Web of Science databases for full text articles published through May 31, 2017 to identify studies addressing the diagnostic accuracy of iFR referenced to FFR≤0.80. The following keywords were used: "instantaneous wave-free ratio" OR "iFR" AND "fractional flow reserve" OR "FFR." In total, 16 studies comprising 5756 lesions were identified. Pooled diagnostic accuracy estimates of iFR versus FFR≤0.80 were: sensitivity, 0.78 (95% CI, 0.76-0.79); specificity, 0.83 (0.81-0.84); positive likelihood ratio, 4.54 (3.85-5.35); negative likelihood ratio, 0.28 (0.24-0.32); diagnostic odds ratio, 17.38 (14.16-21.34); area under the summary receiver-operating characteristic curve, 0.87; and an overall diagnostic accuracy of 0.81 (0.78-0.84). In conclusion, iFR showed excellent agreement with FFR as a resting index of coronary stenosis severity without the undesired effects and cost of hyperemic agents. When considering along with its clinical outcome data and ease of application, the diagnostic accuracy of iFR supports its use as a suitable alternative to FFR for physiology-guided revascularization of moderate coronary stenoses. We performed a meta-analysis of the diagnostic accuracy of iFR referenced to FFR. iFR showed excellent agreement with FFR as a resting index of coronary stenosis severity without the undesired effects and cost of hyperemic agents. This supports its use as a suitable alternative to FFR for physiology-guided revascularization of moderate coronary stenoses. Copyright © 2017. Published by Elsevier Inc.

Using Language Sample Analysis in Clinical Practice: Measures of Grammatical Accuracy for Identifying Language Impairment in Preschool and School-Aged Children.

PubMed

Eisenberg, Sarita; Guo, Ling-Yu

2016-05-01

This article reviews the existing literature on the diagnostic accuracy of two grammatical accuracy measures for differentiating children with and without language impairment (LI) at preschool and early school age based on language samples. The first measure, the finite verb morphology composite (FVMC), is a narrow grammatical measure that computes children's overall accuracy of four verb tense morphemes. The second measure, percent grammatical utterances (PGU), is a broader grammatical measure that computes children's accuracy in producing grammatical utterances. The extant studies show that FVMC demonstrates acceptable (i.e., 80 to 89% accurate) to good (i.e., 90% accurate or higher) diagnostic accuracy for children between 4;0 (years;months) and 6;11 in conversational or narrative samples. In contrast, PGU yields acceptable to good diagnostic accuracy for children between 3;0 and 8;11 regardless of sample types. Given the diagnostic accuracy shown in the literature, we suggest that FVMC and PGU can be used as one piece of evidence for identifying children with LI in assessment when appropriate. However, FVMC or PGU should not be used as therapy goals directly. Instead, when children are low in FVMC or PGU, we suggest that follow-up analyses should be conducted to determine the verb tense morphemes or grammatical structures that children have difficulty with. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Efficiency of the Bethesda System for Thyroid Cytopathology.

PubMed

Mora-Guzmán, Ismael; Muñoz de Nova, José Luis; Marín-Campos, Cristina; Jiménez-Heffernan, José Antonio; Cuesta Pérez, Juan Julián; Lahera Vargas, Marcos; Torres Mínguez, Emma; Martín-Pérez, Elena

2018-03-28

Fine-needle aspiration biopsies are a key tool for preoperative assessment of thyroid nodules, and the Bethesda system is the preferred method to report cytological analysis. The purpose of this study is to assess the efficiency of the Bethesda system to identify the malignancy risk of thyroid nodules. Patients who underwent thyroid surgery between June 2010 and June 2017 were included. Samples were classified into 6categories according to rates of malignancy associated with each diagnostic category. In order to investigate the correlation between categories, a statistical analysis compared the categories with pathology reports. Diagnostic indicators were calculated as a screening test (categories IV, V, VI as true-positive) and as a method to identify malignancy (V, VI as true-positive). In a series of 522 patients, we found 184 (35.2%) malignant tumours, papillary carcinoma being the most prevalent with 155 cases (84.2%). Malignant rates for diagnostic categories were: I, 0%; II, 1.5%; III, 6.4%; IV, 31%; V, 86.5%; VI, 100%. A robust correlation was identified between categories on statistical analysis. For the «screening test» analysis, sensitivity was 98.9%, specificity 84.4%, positive predictive value 69.6%, negative predictive value 99.5%, and diagnostic accuracy 88.2%. Analysing the accuracy to detect malignancy, values were: sensitivity 98.6%, specificity 97.6%, positive predictive value 93.5%, negative predictive value 99.5%, diagnostic accuracy 97.9%. The Bethesda system is a clear and reliable approach to report thyroid cytology and therefore is an effective tool to identify malignancy risk and guide clinical management. Copyright © 2018 AEC. Publicado por Elsevier España, S.L.U. All rights reserved.

Optical coherence tomography for glaucoma diagnosis: An evidence based meta-analysis.

PubMed

Kansal, Vinay; Armstrong, James J; Pintwala, Robert; Hutnik, Cindy

2018-01-01

Early detection, monitoring and understanding of changes in the retina are central to the diagnosis of glaucomatous optic neuropathy, and vital to reduce visual loss from this progressive condition. The main objective of this investigation was to compare glaucoma diagnostic accuracy of commercially available optical coherence tomography (OCT) devices (Zeiss Stratus, Zeiss Cirrus, Heidelberg Spectralis and Optovue RTVue, and Topcon 3D-OCT). 16,104 glaucomatous and 11,543 normal eyes reported in 150 studies. Between Jan. 2017 and Feb 2017, MEDLINE®, EMBASE®, CINAHL®, Cochrane Library®, Web of Science®, and BIOSIS® were searched for studies assessing glaucoma diagnostic accuracy of the aforementioned OCT devices. Meta-analysis was performed pooling area under the receiver operating characteristic curve (AUROC) estimates for all devices, stratified by OCT type (RNFL, macula), and area imaged. 150 studies with 16,104 glaucomatous and 11,543 normal control eyes were included. Key findings: AUROC of glaucoma diagnosis for RNFL average for all glaucoma patients was 0.897 (0.887-0.906, n = 16,782 patient eyes), for macula ganglion cell complex (GCC) was 0.885 (0.869-0.901, n = 4841 eyes), for macula ganglion cell inner plexiform layer (GCIPL) was 0.858 (0.835-0.880, n = 4211 eyes), and for total macular thickness was 0.795 (0.754-0.834, n = 1063 eyes). The classification capability was similar across all 5 OCT devices. More diagnostically favorable AUROCs were demonstrated in patients with increased glaucoma severity. Diagnostic accuracy of RNFL and segmented macular regions (GCIPL, GCC) scans were similar and higher than total macular thickness. This study provides a synthesis of contemporary evidence with features of robust inclusion criteria and large sample size. These findings may provide guidance to clinicians when navigating this rapidly evolving diagnostic area characterized by numerous options.

Application of computer-aided diagnosis (CAD) in MR-mammography (MRM): do we really need whole lesion time curve distribution analysis?

PubMed

Baltzer, Pascal Andreas Thomas; Renz, Diane M; Kullnig, Petra E; Gajda, Mieczyslaw; Camara, Oumar; Kaiser, Werner A

2009-04-01

The identification of the most suspect enhancing part of a lesion is regarded as a major diagnostic criterion in dynamic magnetic resonance mammography. Computer-aided diagnosis (CAD) software allows the semi-automatic analysis of the kinetic characteristics of complete enhancing lesions, providing additional information about lesion vasculature. The diagnostic value of this information has not yet been quantified. Consecutive patients from routine diagnostic studies (1.5 T, 0.1 mmol gadopentetate dimeglumine, dynamic gradient-echo sequences at 1-minute intervals) were analyzed prospectively using CAD. Dynamic sequences were processed and reduced to a parametric map. Curve types were classified by initial signal increase (not significant, intermediate, and strong) and the delayed time course of signal intensity (continuous, plateau, and washout). Lesion enhancement was measured using CAD. The most suspect curve, the curve-type distribution percentage, and combined dynamic data were compared. Statistical analysis included logistic regression analysis and receiver-operating characteristic analysis. Fifty-one patients with 46 malignant and 44 benign lesions were enrolled. On receiver-operating characteristic analysis, the most suspect curve showed diagnostic accuracy of 76.7 +/- 5%. In comparison, the curve-type distribution percentage demonstrated accuracy of 80.2 +/- 4.9%. Combined dynamic data had the highest diagnostic accuracy (84.3 +/- 4.2%). These differences did not achieve statistical significance. With appropriate cutoff values, sensitivity and specificity, respectively, were found to be 80.4% and 72.7% for the most suspect curve, 76.1% and 83.6% for the curve-type distribution percentage, and 78.3% and 84.5% for both parameters. The integration of whole-lesion dynamic data tends to improve specificity. However, no statistical significance backs up this finding.

A novel computer-assisted image analysis of [123I]β-CIT SPECT images improves the diagnostic accuracy of parkinsonian disorders.

PubMed

Goebel, Georg; Seppi, Klaus; Donnemiller, Eveline; Warwitz, Boris; Wenning, Gregor K; Virgolini, Irene; Poewe, Werner; Scherfler, Christoph

2011-04-01

The purpose of this study was to develop an observer-independent algorithm for the correct classification of dopamine transporter SPECT images as Parkinson's disease (PD), multiple system atrophy parkinson variant (MSA-P), progressive supranuclear palsy (PSP) or normal. A total of 60 subjects with clinically probable PD (n = 15), MSA-P (n = 15) and PSP (n = 15), and 15 age-matched healthy volunteers, were studied with the dopamine transporter ligand [(123)I]β-CIT. Parametric images of the specific-to-nondisplaceable equilibrium partition coefficient (BP(ND)) were generated. Following a voxel-wise ANOVA, cut-off values were calculated from the voxel values of the resulting six post-hoc t-test maps. The percentages of the volume of an individual BP(ND) image remaining below and above the cut-off values were determined. The higher percentage of image volume from all six cut-off matrices was used to classify an individual's image. For validation, the algorithm was compared to a conventional region of interest analysis. The predictive diagnostic accuracy of the algorithm in the correct assignment of a [(123)I]β-CIT SPECT image was 83.3% and increased to 93.3% on merging the MSA-P and PSP groups. In contrast the multinomial logistic regression of mean region of interest values of the caudate, putamen and midbrain revealed a diagnostic accuracy of 71.7%. In contrast to a rater-driven approach, this novel method was superior in classifying [(123)I]β-CIT-SPECT images as one of four diagnostic entities. In combination with the investigator-driven visual assessment of SPECT images, this clinical decision support tool would help to improve the diagnostic yield of [(123)I]β-CIT SPECT in patients presenting with parkinsonism at their initial visit.

ST segment/heart rate hysteresis improves the diagnostic accuracy of ECG stress test for coronary artery disease in patients with left ventricular hypertrophy.

PubMed

Zimarino, Marco; Montebello, Elena; Radico, Francesco; Gallina, Sabina; Perfetti, Matteo; Iachini Bellisarii, Francesco; Severi, Silva; Limbruno, Ugo; Emdin, Michele; De Caterina, Raffaele

2016-10-01

The exercise electrocardiographic stress test (ExET) is the most widely used non-invasive diagnostic method to detect coronary artery disease. However, the sole ST depression criteria (ST-max) have poor specificity for coronary artery disease in patients with left ventricular hypertrophy. We hypothesised that ST-segment depression/heart rate hysteresis, depicting the relative behaviour of ST segment depression during the exercise and recovery phase of the test might increase the diagnostic accuracy of ExET for coronary artery disease detection in such patients. In three cardiology centres, we studied 113 consecutive patients (mean age 66 ± 2 years; 88% men) with hypertension-related left ventricular hypertrophy at echocardiography, referred to coronary angiography after an ExET. The following ExET criteria were analysed: ST-max, chronotropic index, heart rate recovery, Duke treadmill score, ST-segment depression/heart rate hysteresis. We detected significant coronary artery disease at coronary angiography in 61 patients (53%). At receiver-operating characteristic analysis, ST-segment depression/heart rate hysteresis had the highest area under the curve value (0.75, P < 0.001 when compared with the 'neutral' receiver-operating characteristic curve value of 0.5). Area under the curve values were 0.68 (P < 0.01) for the chronotropic index, 0.58 (P = NS) for heart rate recovery, 0.57 (P = NS) for ST-max and 0.52 (P = NS) for the Duke treadmill score. Among currently available ExET diagnostic variables, ST-segment depression/heart rate hysteresis offers a substantially better diagnostic accuracy for coronary artery disease than conventional criteria in patients with hypertension-related left ventricular hypertrophy. © The European Society of Cardiology 2016.

Ultrasound for Distal Forearm Fracture: A Systematic Review and Diagnostic Meta-Analysis

PubMed Central

Douma-den Hamer, Djoke; Blanker, Marco H.; Edens, Mireille A.; Buijteweg, Lonneke N.; Boomsma, Martijn F.; van Helden, Sven H.; Mauritz, Gert-Jan

2016-01-01

Study Objective To determine the diagnostic accuracy of ultrasound for detecting distal forearm fractures. Methods A systematic review and diagnostic meta-analysis was performed according to the PRISMA statement. We searched MEDLINE, Web of Science and the Cochrane Library from inception to September 2015. All prospective studies of the diagnostic accuracy of ultrasound versus radiography as the reference standard were included. We excluded studies with a retrospective design and those with evidence of verification bias. We assessed the methodological quality of the included studies with the QUADAS-2 tool. We performed a meta-analysis of studies evaluating ultrasound to calculate the pooled sensitivity and specificity with 95% confidence intervals (CI95%) using a bivariate model with random effects. Subgroup and sensitivity analysis were used to examine the effect of methodological differences and other study characteristics. Results Out of 867 publications we included 16 studies with 1,204 patients and 641 fractures. The pooled test characteristics for ultrasound were: sensitivity 97% (CI95% 93–99%), specificity 95% (CI95% 89–98%), positive likelihood ratio (LR) 20.0 (8.5–47.2) and negative LR 0.03 (0.01–0.08). The corresponding pooled diagnostic odds ratio (DOR) was 667 (142–3,133). Apparent differences were shown for method of viewing, with the 6-view method showing higher specificity, positive LR, and DOR, compared to the 4-view method. Conclusion The present meta-analysis showed that ultrasound has a high accuracy for the diagnosis of distal forearm fractures in children when used by proper viewing method. Based on this, ultrasound should be considered a reliable alternative, which has the advantages of being radiation free. PMID:27196439

Accuracy of Conventional PCR Targeting the 16S rRNA Gene with the Ot-16sRF1 and Ot-16sRR1 Primers for Diagnosis of Scrub Typhus: a Case-Control Study

PubMed Central

Kim, Choon-Mee; Cho, Min Keun; Yun, Na-Ra; Kim, Seok Won; Jang, Sook Jin; Ahn, Young-Joon; Lim, Donghoon

2015-01-01

We retrospectively evaluated the accuracy of conventional PCR targeting the 16S rRNA gene (16S C-PCR) using the Ot-16sRF1/Ot-16sRR1 primers for diagnosing scrub typhus. The diagnosis of Orientia tsutsugamushi infection by 16S C-PCR presented an increased sensitivity of 87.0% and specificity of 100% compared with those obtained with other targets and is thus a simple and clinically useful method with good diagnostic accuracy. PMID:26491185

[Diagnostic of ascites due to portal hypertension: accuracy of the serum-ascites albumin gradient and protein analises in ascitic fluid].

PubMed

Rodríguez Vargas, Brainy Omar; Monge Salgado, Eduardo; Montes Teves, Pedro; Salazar Ventura, Sonia; Guzmán Calderón, Edson

2014-01-01

To evaluate the diagnostic accuracy of the Serum-Ascites Albumin Gradient (GASA), Protein Concentration in the Ascitic Fluid (PTLA), Albumin Concentration in the ascitic fluid (CAA) and the Protein Ascites/Serum Ratio (IPAS) for the diagnosis of ascites due to portal hypertension. it was an observational and retrospective study of validation of diagnostic tests. The study population was patients from a National Public Health Hospital Daniel Alcides Carrion of Callao, Peru, during the period January to December of 2012, patients over 15 years old with a diagnosis of ascites which samples were taken for study by paracentesis with an standard technique, it was analyzed total protein and albumin, as well as study of total protein and albumin in blood. We obtained the diagnostic accuracy, sensitivity, specificity, PPV and NPV of the Serum-Ascites Albumin Gradient (GASA), Protein Concentration in the Ascitic Fluid (PTLA), Albumin Concentration in the ascitic fluid (CAA) and the Protein Ascites/Serum Ratio (IPAS) for the diagnosis of ascites due to portal hypertension. To determine ascites by HTP as diagnostic tests we took into account: GASA >= 1.1, PTLA <2.5, CAA <1.1 or IPAS< 0.5. There were 126 patients diagnosed with ascites, 10 patients was excluded for having incomplete data. Of the 116 patients, the average age was 53.03 +/- 15.73 years old, male 65 (56%) and female 51 (44%). 61 (52%) had ascites due to portal hypertension from liver cirrhosis, and 55 (48%) of ascites due to NO HTP. The sensitivity and specificity for GASA was 93% and 47% respectively, for PTLA was 80% and 89% respectively, for CAA was 85% and 87% respectively and for the IPAS was 83% and 80% respectively. The área under the ROC curve for GASA was 0.70, ATPL was 0.84, IPAS was 0.81 and CAA was 0.86, we found statistically significant differences between GASA compared to the other three parameters (p<0.01 ). The diagnostic accuracy of CAA, ATPL and IPAS is higher than the GASA to discriminate between ascites due to HTP or NO HTP, so that they could be used in clinical practice alone or together to achieve a diagnostic approach more successful.

Utility of PET/CT to Evaluate Retroperitoneal Lymph Node Metastasis in High-Risk Endometrial Cancer: Results of ACRIN 6671/GOG 0233 Trial.

PubMed

Atri, Mostafa; Zhang, Zheng; Dehdashti, Farrokh; Lee, Susanna I; Marques, Helga; Ali, Shamshad; Koh, Wui-Jin; Mannel, Robert S; DiSilvestro, Paul; King, Stephanie A; Pearl, Michael; Zhou, XunClare; Plante, Marie; Moxley, Katherine M; Gold, Michael

2017-05-01

Purpose To assess the diagnostic accuracy of fluorine 18 fluorodeoxyglucose (FDG) positron emission tomography (PET) combined with diagnostic contrast material-enhanced computed tomography (CT) in detecting lymph node (LN) metastasis in high-risk endometrial cancer. Materials and Methods This prospective multicenter HIPAA-compliant study had institutional review board approval, and all participants gave written informed consent. Data were accrued between January 2010 and June 2013. Patients underwent PET/CT and pelvic and abdominal lymphadenectomy. Two hundred seven of 215 enrolled patients had PET/CT and pathologic examination results for the abdomen and pelvis. Mean patient age was 62.7 years ± 9.6 (standard deviation). Data in all 23 patients with a positive abdominal examination and in 26 randomly selected patients with a negative abdominal examination were used for this central reader study. Seven independent blinded readers reviewed diagnostic CT and PET/CT results in different sessions 1 month apart. Accuracy was calculated at the participant level, correlating abdominal (right and left para-aortic and common iliac) and pelvic (right and left external iliac and obturator) LN regions with pathologic results, respecting laterality. Reader-average sensitivities, specificities, and areas under the receiver operating characteristic curve (AUCs) of PET/CT and diagnostic CT were compared. Power calculation was for sensitivity and specificity in the abdomen. Results Sensitivities of PET/CT versus diagnostic CT for the detection of LN metastasis were 0.65 (95% confidence interval [CI]: 0.57, 0.72) versus 0.50 (95% CI: 0.43, 0.58) (P = .01) in the abdomen and 0.65 (95% CI: 0.57, 0.72) versus 0.48 (95% CI: 0.41, 0.56) (P = .004) in the pelvis. Corresponding specificities were 0.88 (95% CI: 0.83, 0.92) versus 0.93 (95% CI: 0.89, 0.96) (P = .11) and 0.93 (95% CI: 0.86, 0.96) versus 0.89 (95% CI: 0.82, 0.94) (P = .27), and AUCs were 0.78 (95% CI: 0.66, 0.89) versus 0.74 (95% CI: 0.63, 0.86) (P = .39) and 0.82 (95% CI: 0.71, 0.92) versus 0.73 (95% CI: 0.63, 0.84) (P = .02). Conclusion FDG PET/CT has satisfactory diagnostic accuracy in the detection of abdominal LN metastasis in high-risk endometrial cancer. Compared with diagnostic CT alone, addition of PET to diagnostic CT significantly increased sensitivity in both the abdomen and pelvis while maintaining high specificity. © RSNA, 2017 Online supplemental material is available for this article.

Utility of PET/CT to Evaluate Retroperitoneal Lymph Node Metastasis in High-Risk Endometrial Cancer: Results of ACRIN 6671/GOG 0233 Trial

PubMed Central

Zhang, Zheng; Dehdashti, Farrokh; Lee, Susanna I.; Marques, Helga; Ali, Shamshad; Koh, Wui-Jin; Mannel, Robert S.; DiSilvestro, Paul; King, Stephanie A.; Pearl, Michael; Zhou, XunClare; Plante, Marie; Moxley, Katherine M.; Gold, Michael

2017-01-01

Purpose To assess the diagnostic accuracy of fluorine 18 fluorodeoxyglucose (FDG) positron emission tomography (PET) combined with diagnostic contrast material–enhanced computed tomography (CT) in detecting lymph node (LN) metastasis in high-risk endometrial cancer. Materials and Methods This prospective multicenter HIPAA-compliant study had institutional review board approval, and all participants gave written informed consent. Data were accrued between January 2010 and June 2013. Patients underwent PET/CT and pelvic and abdominal lymphadenectomy. Two hundred seven of 215 enrolled patients had PET/CT and pathologic examination results for the abdomen and pelvis. Mean patient age was 62.7 years ± 9.6 (standard deviation). Data in all 23 patients with a positive abdominal examination and in 26 randomly selected patients with a negative abdominal examination were used for this central reader study. Seven independent blinded readers reviewed diagnostic CT and PET/CT results in different sessions 1 month apart. Accuracy was calculated at the participant level, correlating abdominal (right and left para-aortic and common iliac) and pelvic (right and left external iliac and obturator) LN regions with pathologic results, respecting laterality. Reader-average sensitivities, specificities, and areas under the receiver operating characteristic curve (AUCs) of PET/CT and diagnostic CT were compared. Power calculation was for sensitivity and specificity in the abdomen. Results Sensitivities of PET/CT versus diagnostic CT for the detection of LN metastasis were 0.65 (95% confidence interval [CI]: 0.57, 0.72) versus 0.50 (95% CI: 0.43, 0.58) (P = .01) in the abdomen and 0.65 (95% CI: 0.57, 0.72) versus 0.48 (95% CI: 0.41, 0.56) (P = .004) in the pelvis. Corresponding specificities were 0.88 (95% CI: 0.83, 0.92) versus 0.93 (95% CI: 0.89, 0.96) (P = .11) and 0.93 (95% CI: 0.86, 0.96) versus 0.89 (95% CI: 0.82, 0.94) (P = .27), and AUCs were 0.78 (95% CI: 0.66, 0.89) versus 0.74 (95% CI: 0.63, 0.86) (P = .39) and 0.82 (95% CI: 0.71, 0.92) versus 0.73 (95% CI: 0.63, 0.84) (P = .02). Conclusion FDG PET/CT has satisfactory diagnostic accuracy in the detection of abdominal LN metastasis in high-risk endometrial cancer. Compared with diagnostic CT alone, addition of PET to diagnostic CT significantly increased sensitivity in both the abdomen and pelvis while maintaining high specificity. © RSNA, 2017 Online supplemental material is available for this article. PMID:28051912

Comparison and Combination of Strain and Shear Wave Elastography of Breast Masses for Differentiation of Benign and Malignant Lesions by Quantitative Assessment: Preliminary Study.

PubMed

Seo, Mirinae; Ahn, Hye Shin; Park, Sung Hee; Lee, Jong Beum; Choi, Byung Ihn; Sohn, Yu-Mee; Shin, So Youn

2018-01-01

To compare the diagnostic performance of strain and shear wave elastography of breast masses for quantitative assessment in differentiating benign and malignant lesions and to evaluate the diagnostic accuracy of combined strain and shear wave elastography. Between January and February 2016, 37 women with 45 breast masses underwent both strain and shear wave ultrasound (US) elastographic examinations. The American College of Radiology Breast Imaging Reporting and Data System (BI-RADS) final assessment on B-mode US imaging was assessed. We calculated strain ratios for strain elastography and the mean elasticity value and elasticity ratio of the lesion to fat for shear wave elastography. Diagnostic performances were compared by using the area under the receiver operating characteristic curve (AUC). The 37 women had a mean age of 47.4 years (range, 20-79 years). Of the 45 lesions, 20 were malignant, and 25 were benign. The AUCs for elasticity values on strain and shear wave elastography showed no significant differences (strain ratio, 0.929; mean elasticity, 0.898; and elasticity ratio, 0.868; P > .05). After selectively downgrading BI-RADS category 4a lesions based on strain and shear wave elastographic cutoffs, the AUCs for the combined sets of B-mode US and elastography were improved (B-mode + strain, 0.940; B-mode + shear wave; 0.964; and B-mode, 0.724; P < .001). Combined strain and shear wave elastography showed significantly higher diagnostic accuracy than each individual elastographic modality (P = .031). These preliminary results showed that strain and shear wave elastography had similar diagnostic performance. The addition of strain and shear wave elastography to B-mode US improved diagnostic performance. The combination of strain and shear wave elastography results in a higher diagnostic yield than each individual elastographic modality. © 2017 by the American Institute of Ultrasound in Medicine.

Diagnostic precision of mentally estimated home blood pressure means.

PubMed

Ouattara, Franck Olivier; Laskine, Mikhael; Cheong, Nathalie Ng; Birnbaum, Leora; Wistaff, Robert; Bertrand, Michel; van Nguyen, Paul; Kolan, Christophe; Durand, Madeleine; Rinfret, Felix; Lamarre-Cliche, Maxime

2018-05-07

Paper home blood pressure (HBP) charts are commonly brought to physicians at office visits. The precision and accuracy of mental calculations of blood pressure (BP) means are not known. A total of 109 hypertensive patients were instructed to measure and record their HBP for 1 week and to bring their paper charts to their office visit. Study section 1: HBP means were calculated electronically and compared to corresponding in-office BP estimates made by physicians. Study section 2: 100 randomly ordered HBP charts were re-examined repetitively by 11 evaluators. Each evaluator estimated BP means four times in 5, 15, 30, and 60 s (random order) allocated for the task. BP means and diagnostic performance (determination of therapeutic systolic and diastolic BP goals attained or not) were compared between physician estimates and electronically calculated results. Overall, electronically and mentally calculated BP means were not different. Individual analysis showed that 83% of in-office physician estimates were within a 5-mmHg systolic BP range. There was diagnostic disagreement in 15% of cases. Performance improved consistently when the time allocated for BP estimation was increased from 5 to 15 s and from 15 to 30 s, but not when it exceeded 30 s. Mentally calculating HBP means from paper charts can cause a number of diagnostic errors. Chart evaluation exceeding 30 s does not significantly improve accuracy. BP-measuring devices with modern analytical capacities could be useful to physicians.

Does McNemar's test compare the sensitivities and specificities of two diagnostic tests?

PubMed

Kim, Soeun; Lee, Woojoo

2017-02-01

McNemar's test is often used in practice to compare the sensitivities and specificities for the evaluation of two diagnostic tests. For correct evaluation of accuracy, an intuitive recommendation is to test the diseased and the non-diseased groups separately so that the sensitivities can be compared among the diseased, and specificities can be compared among the healthy group of people. This paper provides a rigorous theoretical framework for this argument and study the validity of McNemar's test regardless of the conditional independence assumption. We derive McNemar's test statistic under the null hypothesis considering both assumptions of conditional independence and conditional dependence. We then perform power analyses to show how the result is affected by the amount of the conditional dependence under alternative hypothesis.

Diagnostic accuracy of a noninvasive hepatic ultrasound score for non-alcoholic fatty liver disease (NAFLD) in the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil).

PubMed

Goulart, Alessandra Carvalho; Oliveira, Ilka Regina Souza de; Alencar, Airlane Pereira; Santos, Maira Solange Camara dos; Santos, Itamar Souza; Martines, Brenda Margatho Ramos; Meireles, Danilo Peron; Martines, João Augusto dos Santos; Misciagna, Giovanni; Benseñor, Isabela Martins; Lotufo, Paulo Andrade

2015-01-01

Noninvasive strategies for evaluating non-alcoholic fatty liver disease (NAFLD) have been investigated over the last few decades. Our aim was to evaluate the diagnostic accuracy of a new hepatic ultrasound score for NAFLD in the ELSA-Brasil study. Diagnostic accuracy study conducted in the ELSA center, in the hospital of a public university. Among the 15,105 participants of the ELSA study who were evaluated for NAFLD, 195 individuals were included in this sub-study. Hepatic ultrasound was performed (deep beam attenuation, hepatorenal index and anteroposterior diameter of the right hepatic lobe) and compared with the hepatic steatosis findings from 64-channel high-resolution computed tomography (CT). We also evaluated two clinical indices relating to NAFLD: the fatty liver index (FLI) and the hepatic steatosis index (HSI). Among the 195 participants, the NAFLD frequency was 34.4%. High body mass index, high waist circumference, diabetes and hypertriglyceridemia were associated with high hepatic attenuation and large anteroposterior diameter of the right hepatic lobe, but not with the hepatorenal index. The hepatic ultrasound score, based on hepatic attenuation and the anteroposterior diameter of the right hepatic lobe, presented the best performance for NAFLD screening at the cutoff point ≥ 1 point; sensitivity: 85.1%; specificity: 73.4%; accuracy: 79.3%; and area under the curve (AUC 0.85; 95% confidence interval, CI: 0.78-0.91)]. FLI and HSI presented lower performance (AUC 0.76; 95% CI: 0.69-0.83) than CT. The hepatic ultrasound score based on hepatic attenuation and the anteroposterior diameter of the right hepatic lobe has good reproducibility and accuracy for NAFLD screening.

Accuracy of diagnostic imaging modalities for peripheral post-traumatic osteomyelitis - a systematic review of the recent literature.

PubMed

Govaert, Geertje A; IJpma, Frank F; McNally, Martin; McNally, Eugene; Reininga, Inge H; Glaudemans, Andor W

2017-08-01

Post-traumatic osteomyelitis (PTO) is difficult to diagnose and there is no consensus on the best imaging strategy. The aim of this study is to present a systematic review of the recent literature on diagnostic imaging of PTO. A literature search of the EMBASE and PubMed databases of the last 16 years (2000-2016) was performed. Studies that evaluated the accuracy of magnetic resonance imaging (MRI), three-phase bone scintigraphy (TPBS), white blood cell (WBC) or antigranulocyte antibody (AGA) scintigraphy, fluorodeoxyglucose positron emission tomography (FDG-PET) and plain computed tomography (CT) in diagnosing PTO were considered for inclusion. The review was conducted using the PRISMA statement and QUADAS-2 criteria. The literature search identified 3358 original records, of which 10 articles could be included in this review. Four of these studies had a comparative design which made it possible to report the results of, in total, 17 patient series. WBC (or AGA) scintigraphy and FDG-PET exhibit good accuracy for diagnosing PTO (sensitivity ranged from 50-100%, specificity ranged from 40-97% versus 83-100% and 51%-100%, respectively). The accuracy of both modalities improved when a hybrid imaging technique (SPECT/CT & FDG-PET/CT) was performed. For FDG-PET/CT, sensitivity ranged between 86 and 94% and specificity between 76 and 100%. For WBC scintigraphy + SPECT/CT, this is 100% and 89-97%, respectively. Based on the best available evidence of the last 16 years, both WBC (or AGA) scintigraphy combined with SPECT/CT or FDG-PET combined with CT have the best diagnostic accuracy for diagnosing peripheral PTO.

Comparison of Diagnostic Accuracy between Octopus 900 and Goldmann Kinetic Visual Fields

PubMed Central

Rowe, Fiona J.; Rowlands, Alison

2014-01-01

Purpose. To determine diagnostic accuracy of kinetic visual field assessment by Octopus 900 perimetry compared with Goldmann perimetry. Methods. Prospective cross section evaluation of 40 control subjects with full visual fields and 50 patients with known visual field loss. Comparison of test duration and area measurement of isopters for Octopus 3, 5, and 10°/sec stimulus speeds. Comparison of test duration and type of visual field classification for Octopus versus Goldmann perimetry. Results were independently graded for presence/absence of field defect and for type and location of defect. Statistical evaluation comprised of ANOVA and paired t test for evaluation of parametric data with Bonferroni adjustment. Bland Altman and Kappa tests were used for measurement of agreement between data. Results. Octopus 5°/sec perimetry had comparable test duration to Goldmann perimetry. Octopus perimetry reliably detected type and location of visual field loss with visual fields matched to Goldmann results in 88.8% of results (K = 0.775). Conclusions. Kinetic perimetry requires individual tailoring to ensure accuracy. Octopus perimetry was reproducible for presence/absence of visual field defect. Our screening protocol when using Octopus perimetry is 5°/sec for determining boundaries of peripheral isopters and 3°/sec for blind spot mapping with further evaluation of area of field loss for defect depth and size. PMID:24587983

Mothers' Estimates of Their Children with Disorders of Language Development

ERIC Educational Resources Information Center

Willinger, Ulrike; Eisenwort, Brigitte

2005-01-01

The authors' objective in this article was to explore the accuracy of mothers' estimates concerning their children's developmental functioning, especially with respect to vocabulary and gross motor development, by comparing the results of diagnostic tests administered to both the children and their mothers. The authors studied 55 children with…

Diagnostic Accuracy of Chinese Medicine Diagnosis Scale of Phlegm and Blood Stasis Syndrome in Coronary Heart Disease: A Study Protocol.

PubMed

Liu, Xiao-Qi; Peng, Dan-Hong; Wang, Yan-Ping; Xie, Rong; Chen, Xin-Lin; Yu, Chun-Quan; Li, Xian-Tao

2018-05-03

Phlegm and blood stasis syndrome (PBSS) is one of the main syndromes in coronary heart disease (CHD). Syndromes of Chinese medicine (CM) are lack of quantitative and easyimplementation diagnosis standards. To quantify and standardize the diagnosis of PBSS, scales are usually applied. To evaluate the diagnostic accuracy of CM diagnosis scale of PBSS in CHD. Six hundred patients with stable angina pectoris of CHD, 300 in case group and 300 in control group, will be recruited from 5 hospitals across China. Diagnosis from 2 experts will be considered as the "gold standard". The study design consists of 2 phases: pilot test is used to evaluate the reliability and validity, and diagnostic test is used to assess the diagnostic accuracy of the scale, including sensitivity, specififi city, likelihood ratio and area under the receiver operator characteristic (ROC) curve. This study will evaluate the diagnostic accuracy of CM diagnosis scale of PBSS in CHD. The consensus of 2 experts may not be ideal as a "gold standard", and itself still requires further study. (No. ChiCTR-OOC-15006599).

Diagnostic accuracy and cost-effectiveness of different strategies to triage women with adnexal masses: a prospective study.

PubMed

Piovano, E; Cavallero, C; Fuso, L; Viora, E; Ferrero, A; Gregori, G; Grillo, C; Macchi, C; Mengozzi, G; Mitidieri, M; Pagano, E; Zola, P

2017-09-01

Transvaginal sonography (TVS) and serum biomarkers are used widely in clinical practice to triage women with adnexal masses, but the effectiveness of current biomarkers is weak. The aim of this study was to determine the best method of diagnosing patients with adnexal masses, in terms of diagnostic accuracy and economic costs, among four triage strategies: (1) the International Ovarian Tumor Analysis group's simple rules (SR) for interpretation of TVS with subjective assessment (SA) by an experienced ultrasound operator when TVS results are inconclusive (referred to hereafter as SR ± SA), (2) SR ± SA and cancer antigen 125 (CA 125), (3) SR ± SA and human epididymis protein 4 (HE4) and (4) SR ± SA and the risk of malignancy algorithm (ROMA). Our main hypothesis was that the addition of the biomarkers to SR ± SA could improve triaging of these patients in terms of diagnostic accuracy (i.e. malignant vs benign). As secondary analyses, we estimated the cost effectiveness of the four strategies and the diagnostic accuracy of SR ± SA at the study hospitals. Between February 2013 and January 2015, 447 consecutive patients who were scheduled for surgery for an adnexal mass at the S. Anna and Mauriziano Hospitals in Turin were enrolled in this multicenter prospective cohort study. Preoperative TVS was performed and preoperative CA 125 and HE4 levels were measured. Pathology reports were used to assess the diagnostic accuracy of the four triage strategies and the cost of each strategy was calculated. A total of 391 patients were included in the analysis: 57% (n = 221) were premenopausal and 43% (n = 170) were postmenopausal. The overall prevalence of malignancy was 21%. SR were conclusive in 89% of patients and thus did not require SA; the overall performance of SR ± SA showed a sensitivity of 82%, specificity of 92% and positive and negative predictive values and positive and negative likelihood ratios of 74%, 95%, 10.5 and 0.19, respectively. In premenopausal women, mean cost among the four triage strategies varied from €36.41 for SR ± SA to €70.12 for SR ± SA + ROMA. The addition of biomarkers to SR ± SA showed no diagnostic advantage compared with SR ± SA alone and was more costly. Among postmenopausal women, mean cost among the four triage strategies varied from €39.52 for SR ± SA to €73.23 for SR ± SA + ROMA. Among these women, SR ± SA + CA 125 and SR ± SA + ROMA had a higher sensitivity (both 92% (95% CI, 85-99%)) than SR ± SA (81% (95% CI, 71-91%)), but SR ± SA had a higher specificity (84% (95% CI, 77-91%)). SR ± SA + CA 125 and SR ± SA + ROMA improved diagnostic accuracy, each diagnosing a third more malignant adnexal masses. In postmenopausal women, compared with SR ± SA alone, SR ± SA + CA 125 showed a net reclassification improvement (NRI) of 28.8% at an extra cost of €13.00, while the extra cost for SR ± SA + ROMA was €33.71, with a comparable gain, in terms of NRI, as that of SR ± SA + CA 125. In our study sample, SR ± SA seems to be the best strategy to triage women with adnexal masses for surgical management. Among postmenopausal women, SR ± SA + CA 125 increased the NRI at a reasonable extra cost. Our data do not justify the use of HE4 and ROMA in the initial triage of women with adnexal masses. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd.

The role of serum erythropoietin level and JAK2 V617F allele burden in the diagnosis of polycythaemia vera.

PubMed

Ancochea, Agueda; Alvarez-Larrán, Alberto; Morales-Indiano, Cristian; García-Pallarols, Francesc; Martínez-Avilés, Luz; Angona, Anna; Senín, Alicia; Bellosillo, Beatriz; Besses, Carles

2014-11-01

Low serum erythropoietin (EPO) is a minor criterion of Polycythaemia Vera (PV) but its diagnostic usefulness relies on studies performed before the discovery of JAK2 V617F mutation. The objective of the present study was to evaluate the diagnostic accuracy of serum EPO and JAK2 V617F allele burden as markers of PV as well as the combination of different diagnostic criteria in 287 patients (99 with PV, 137 with Essential Thrombocythaemia and 51 with non-clonal erythrocytosis). Low EPO showed good diagnostic accuracy as a marker for PV, with the area under the curve (AUC) of the chemiluminescent-enhanced enzyme immunoassay (CEIA) being better than that of radioimmunoassay (RIA) (0·87 and 0·76 for CEIA and RIA, respectively). JAK2 V617F quantification displayed an excellent diagnostic accuracy, with an AUC of 0·95. A haematocrit >52% (males) or >48% (females) plus the presence of the JAK2 V617F mutation had a sensitivity and specificity of 79% and 97%, respectively. Adding low EPO or the JAK2 V617F allele burden did not improve the diagnostic accuracy for PV whereas the inclusion of both improved the sensitivity up to 83% and maintaining 96% specificity. Haematocrit and qualitative JAK2 V617F mutation allow a reliable diagnosis of PV. Incorporation of EPO and/or JAK2 V617F mutant load does not improve the diagnostic accuracy. © 2014 John Wiley & Sons Ltd.

Estimation of diagnostic test accuracy without full verification: a review of latent class methods

PubMed Central

Collins, John; Huynh, Minh

2014-01-01

The performance of a diagnostic test is best evaluated against a reference test that is without error. For many diseases, this is not possible, and an imperfect reference test must be used. However, diagnostic accuracy estimates may be biased if inaccurately verified status is used as the truth. Statistical models have been developed to handle this situation by treating disease as a latent variable. In this paper, we conduct a systematized review of statistical methods using latent class models for estimating test accuracy and disease prevalence in the absence of complete verification. PMID:24910172

Is diagnostic accuracy for detecting pulmonary nodules in chest CT reduced after a long day of reading?

NASA Astrophysics Data System (ADS)

Krupinski, Elizabeth A.; Berbaum, Kevin S.; Caldwell, Robert; Schartz, Kevin M.

2012-02-01

Radiologists are reading more cases with more images, especially in CT and MRI and thus working longer hours than ever before. There have been concerns raised regarding fatigue and whether it impacts diagnostic accuracy. This study measured the impact of reader visual fatigue by assessing symptoms, visual strain via dark focus of accommodation, and diagnostic accuracy. Twenty radiologists and 20 radiology residents were given two diagnostic performance tests searching CT chest sequences for a solitary pulmonary nodule before (rested) and after (tired) a day of clinical reading. 10 cases used free search and navigation, and the other 100 cases used preset scrolling speed and duration. Subjects filled out the Swedish Occupational Fatigue Inventory (SOFI) and the oculomotor strain subscale of the Simulator Sickness Questionnaire (SSQ) before each session. Accuracy was measured using ROC techniques. Using Swensson's technique yields an ROC area = 0.86 rested vs. 0.83 tired, p (one-tailed) = 0.09. Using Swensson's LROC technique yields an area = 0.73 rested vs. 0.66 tired, p (one-tailed) = 0.09. Using Swensson's Loc Accuracy technique yields an area = 0.77 rested vs. 0.72 tired, p (one-tailed) = 0.13). Subjective measures of fatigue increased significantly from early to late reading. To date, the results support our findings with static images and detection of bone fractures. Radiologists at the end of a long work day experience greater levels of measurable visual fatigue or strain, contributing to a decrease in diagnostic accuracy. The decrease in accuracy was not as great however as with static images.

Effect of varying displays and room illuminance on caries diagnostic accuracy in digital dental radiographs.

PubMed

Pakkala, T; Kuusela, L; Ekholm, M; Wenzel, A; Haiter-Neto, F; Kortesniemi, M

2012-01-01

In clinical practice, digital radiographs taken for caries diagnostics are viewed on varying types of displays and usually in relatively high ambient lighting (room illuminance) conditions. Our purpose was to assess the effect of room illuminance and varying display types on caries diagnostic accuracy in digital dental radiographs. Previous studies have shown that the diagnostic accuracy of caries detection is significantly better in reduced lighting conditions. Our hypothesis was that higher display luminance could compensate for this in higher ambient lighting conditions. Extracted human teeth with approximal surfaces clinically ranging from sound to demineralized were radiographed and evaluated by 3 observers who detected carious lesions on 3 different types of displays in 3 different room illuminance settings ranging from low illumination, i.e. what is recommended for diagnostic viewing, to higher illumination levels corresponding to those found in an average dental office. Sectioning and microscopy of the teeth validated the presence or absence of a carious lesion. Sensitivity, specificity and accuracy were calculated for each modality and observer. Differences were estimated by analyzing the binary data assuming the added effects of observer and modality in a generalized linear model. The observers obtained higher sensitivities in lower illuminance settings than in higher illuminance settings. However, this was related to a reduction in specificity, which meant that there was no significant difference in overall accuracy. Contrary to our hypothesis, there were no significant differences between the accuracy of different display types. Therefore, different displays and room illuminance levels did not affect the overall accuracy of radiographic caries detection. Copyright © 2012 S. Karger AG, Basel.

Confidence interval estimation of the difference between two sensitivities to the early disease stage.

PubMed

Dong, Tuochuan; Kang, Le; Hutson, Alan; Xiong, Chengjie; Tian, Lili

2014-03-01

Although most of the statistical methods for diagnostic studies focus on disease processes with binary disease status, many diseases can be naturally classified into three ordinal diagnostic categories, that is normal, early stage, and fully diseased. For such diseases, the volume under the ROC surface (VUS) is the most commonly used index of diagnostic accuracy. Because the early disease stage is most likely the optimal time window for therapeutic intervention, the sensitivity to the early diseased stage has been suggested as another diagnostic measure. For the purpose of comparing the diagnostic abilities on early disease detection between two markers, it is of interest to estimate the confidence interval of the difference between sensitivities to the early diseased stage. In this paper, we present both parametric and non-parametric methods for this purpose. An extensive simulation study is carried out for a variety of settings for the purpose of evaluating and comparing the performance of the proposed methods. A real example of Alzheimer's disease (AD) is analyzed using the proposed approaches. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

The Accuracy of Diagnostic Tests for Lyme Disease in Humans, A Systematic Review and Meta-Analysis of North American Research.

PubMed

Waddell, Lisa A; Greig, Judy; Mascarenhas, Mariola; Harding, Shannon; Lindsay, Robbin; Ogden, Nicholas

2016-01-01

There has been an increasing incidence of Lyme disease (LD) in Canada and the United States corresponding to the expanding range of the Ixodes tick vector and Lyme disease agent (Borrelia burgdorferi sensu stricto). There are many diagnostic tests for LD available in North America, all of which have some performance issues, and physicians are concerned about the appropriate use and interpretation of these tests. The objective of this systematic review is to summarize the North American evidence on the accuracy of diagnostic tests and test regimes at various stages of LD. Included in the review are 48 studies on diagnostic tests used in North America published since 1995. Thirteen studies examined a two-tier serological test protocol vs. clinical diagnosis, 24 studies examined single assays vs. clinical diagnosis, 9 studies examined single immunoblot vs. clinical diagnosis, 7 studies compared culture or PCR direct detection methods vs. clinical diagnosis, 22 studies compared two or more tests with each other and 8 studies compared a two-tiered serological test protocol to another test. Recent studies examining the sensitivity and specificity of various test protocols noted that the Immunetics® C6 B. burgdorferi ELISA™ and the two tier approach have superior specificity compared to proposed replacements, and the CDC recommended western blot algorithm has equivalent or superior specificity over other proposed test algorithms. There is a dramatic increase in test sensitivity with progression of B. burgdorferi infection from early to late LD. Direct detection methods, culture and PCR of tissue or blood samples were not as sensitive or timely compared to serological testing. It was also noted that there are a large number of both commercial (n = 42) and in-house developed tests used by private laboratories which have not been evaluated in the primary literature.

The Accuracy of Diagnostic Tests for Lyme Disease in Humans, A Systematic Review and Meta-Analysis of North American Research

PubMed Central

Lindsay, Robbin; Ogden, Nicholas

2016-01-01

There has been an increasing incidence of Lyme disease (LD) in Canada and the United States corresponding to the expanding range of the Ixodes tick vector and Lyme disease agent (Borrelia burgdorferi sensu stricto). There are many diagnostic tests for LD available in North America, all of which have some performance issues, and physicians are concerned about the appropriate use and interpretation of these tests. The objective of this systematic review is to summarize the North American evidence on the accuracy of diagnostic tests and test regimes at various stages of LD. Included in the review are 48 studies on diagnostic tests used in North America published since 1995. Thirteen studies examined a two-tier serological test protocol vs. clinical diagnosis, 24 studies examined single assays vs. clinical diagnosis, 9 studies examined single immunoblot vs. clinical diagnosis, 7 studies compared culture or PCR direct detection methods vs. clinical diagnosis, 22 studies compared two or more tests with each other and 8 studies compared a two-tiered serological test protocol to another test. Recent studies examining the sensitivity and specificity of various test protocols noted that the Immunetics® C6 B. burgdorferi ELISA™ and the two tier approach have superior specificity compared to proposed replacements, and the CDC recommended western blot algorithm has equivalent or superior specificity over other proposed test algorithms. There is a dramatic increase in test sensitivity with progression of B. burgdorferi infection from early to late LD. Direct detection methods, culture and PCR of tissue or blood samples were not as sensitive or timely compared to serological testing. It was also noted that there are a large number of both commercial (n = 42) and in-house developed tests used by private laboratories which have not been evaluated in the primary literature. PMID:28002488

Highly Sensitive Troponin I Followed by Advanced Coronary Artery Disease Assessment Using Computed Tomography Angiography Improves Acute Coronary Syndrome Risk Stratification Accuracy and Work-up in Acute Chest Pain Patients: Results from ROMICAT II Trial

PubMed Central

Mayrhofer, Thomas; Puchner, Stefan B.; Lu, Michael T.; Maurovich-Horvat, Pal; Pope, J. Hector; Truong, Quynh A.; Udelson, James E.; Peacock, W. Frank; White, Charles S.; Woodard, Pamela K.; Fleg, Jerome L.; Nagurney, John T.; Januzzi, James L.; Hoffmann, Udo

2015-01-01

Objectives We compared diagnostic accuracy of conventional troponin/traditional coronary artery disease (CAD) assessment and highly sensitive troponin (hsTn) I/advanced CAD assessment for acute coronary syndrome (ACS) during the index hospitalization. Background HsTn I and advanced assessment of CAD using coronary computed tomography angiography (CTA) are promising candidates to improve the accuracy of emergency department (ED) evaluation of patients with suspected ACS. Methods We performed an observational cohort study in patients with suspected ACS enrolled in the ROMICAT II trial and randomized to coronary CTA who also had hsTn I measurement at the time of the ED presentation. We assessed coronary CTA for traditional (no CAD, non-obstructive CAD, ≥50% stenosis) and advanced features of CAD (≥50% stenosis, high-risk plaque features: positive remodeling, low <30 Hounsfield Units plaque, napkin ring sign, spotty calcium). Results Of 160 patients (mean age: 53±8 years, 40% women) 10.6% were diagnosed with ACS. The ACS rate in patients with HsTn I below the limit of detection (n=9, 5.6%), intermediate (n=139, 86.9%), and above the 99th percentile (n=12, 7.5%) was 0%, 8.6%, and 58.3%, respectively. Absence of ≥50% stenosis and high-risk plaque ruled out ACS in patients with intermediate hsTn I (n=87, 54.4%; ACS rate 0%), while patients with both ≥50% stenosis and high-risk plaque were at high risk (n=13, 8.1%; ACS rate 69.2%) and patients with either ≥50% stenosis or high-risk plaque were at intermediate risk for ACS (n=39, 24.4%; ACS rate 7.7%). HsTn I/advanced coronary CTA assessment significantly improved the diagnostic accuracy for ACS as compared to conventional troponin/traditional coronary CTA (AUC 0.84, 95%CI 0.80-0.88 vs. 0.74, 95%CI 0.70-0.78; p<0.001). Conclusions HsTn I at the time of presentation followed by early advanced coronary CTA assessment improves the risk stratification and diagnostic accuracy for ACS as compared to conventional troponin and traditional coronary CTA assessment. (Multicenter Study to Rule Out Myocardial Infarction/Ischemia by Cardiac Computed Tomography [ROMICAT-II]; NCT01084239) PMID:26476506

Optimisation of the digital radiographic imaging of suspected non-accidental injury

NASA Astrophysics Data System (ADS)

Offiah, Amaka

Aim: To optimise the digital (radiographic) imaging of children presenting with suspected non-accidental injury (NAI). Objectives: (i) To evaluate existing radiographic quality criteria, and to develop a more suitable system if these are found to be inapplicable to skeletal surveys obtained in suspected NAI. (ii) To document differences in image quality between conventional film-screen and the recently installed Fuji5000R computed radiography (CR) system at Great Ormond Street Hospital for Children, (iii) To document the extent of variability in the standard of skeletal surveys obtained in the UK for suspected NAI. (iv) To determine those radiographic parameters which yield the highest diagnostic accuracy, while still maintaining acceptable radiation dose to the child, (v) To determine how varying degrees of edge-enhancement affect diagnostic accuracy. (vi) To establish the accuracy of soft compared to hard copy interpretation of images in suspected NAI. Materials and Methods: (i) and (ii) Retrospective analysis of 286 paediatric lateral spine radiographs by two observers based on the Commission of European Communities (CEC) quality criteria, (iii) Review of the skeletal surveys of 50 consecutive infants referred from hospitals throughout the United Kingdom (UK) with suspected NAI. (iv) Phantom studies. Leeds TO. 10 and TO. 16 test objects were used to compare the relationship between film density, exposure parameters and visualisation of object details, (iv) Clinical study. Anteroposterior and lateral post mortem skull radiographs of six consecutive infants were obtained at various exposures. Six observers independently scored the images based on visualisation of five criteria, (v) and (vi) A study of diagnostic accuracy in which six observers independently interpreted 50 radiographs from printed copies (with varying degrees of edge-enhancement) and from a monitor. Results: The CEC criteria are useful for optimisation of imaging parameters and allow the detection of differences in quality of film-screen and digital images. There is much variability in the quality and number of radiographs performed as part of skeletal surveys in the UK for suspected NAI. The Leeds test objects are either not sensitive enough (TO. 10) or perhaps over sensitive (TO. 16) for the purposes of this project. Furthermore, the minimum spatial resolution required for digital imaging in NAI has not been established. Therefore the objective interpretation of phantom studies is difficult. There is scope for reduction of radiation dose to children with no effect on image quality. Diagnostic accuracy (fracture detection) in suspected NAI is generally low, and is not affected by image display modality. Conclusions: The CEC quality criteria are not applicable to the assessment of clinical image quality. A national protocol for skeletal surveys in NAI is required. Dedicated training, close supervision, collaboration and consistent exposure of radiologists to cases of NAI should improve diagnostic accuracy. The potential exists for dose reduction when performing skeletal surveys in children and infants with suspected NAI. Future studies should address this issue.

Contribution of diffusion weighted MRI to diagnosis and staging in gastric tumors and comparison with multi-detector computed tomography.

PubMed

Arslan, Harun; Fatih Özbay, Mehmet; Çallı, İskan; Doğan, Erkan; Çelik, Sebahattin; Batur, Abdussamet; Bora, Aydın; Yavuz, Alpaslan; Bulut, Mehmet Deniz; Özgökçe, Mesut; Çetin Kotan, Mehmet

2017-03-01

Diagnostic performance of Diffusion-Weighted magnetic resonance Imaging (DWI) and Multi-Detector Computed Tomography (MDCT) for TNM (Tumor, Lymph node, Metastasis) staging of gastric cancer was compared. We used axial T2-weighted images and DWI (b-0,400 and b-800 s/mm2) protocol on 51 pre-operative patients who had been diagnosed with gastric cancer. We also conducted MDCT examinations on them. We looked for a signal increase in the series of DWI images. The depth of tumor invasion in the stomach wall (tumor (T) staging), the involvement of lymph nodes (nodal (N) staging), and the presence or absence of metastases (metastatic staging) in DWI and CT images according to the TNM staging system were evaluated. In each diagnosis of the tumors, sensitivity, specificity, positive and negative accuracy rates of DWI and MDCT examinations were found through a comparison with the results of the surgical pathology, which is the gold standard method. In addition to the compatibilities of each examination with surgical pathology, kappa statistics were used. Sensitivity and specificity of DWI and MDCT in lymph node staging were as follows: N1: DWI: 75.0%, 84.6%; MDCT: 66.7%, 82%;N2: DWI: 79.3%, 77.3%; MDCT: 69.0%, 68.2%; N3: DWI: 60.0%, 97.6%; MDCT: 50.0%, 90.2%. The diagnostic tool DWI seemed more compatible with the gold standard method (surgical pathology), especially in the staging of lymph node, when compared to MDCT. On the other hand, in T staging, the results of DWI and MDCT were better than the gold standard when the T stage increased. However, DWI did not demonstrate superiority to MDCT. The sensitivity and specificity of both imaging techniques for detecting distant metastasis were 100%. The diagnostic accuracy of DWI for TNM staging in gastric cancer before surgery is at a comparable level with MDCT and adding DWI to routine protocol of evaluating lymph nodes metastasis might increase diagnostic accuracy.

The diagnostic performance of CT-derived fractional flow reserve for evaluation of myocardial ischaemia confirmed by invasive fractional flow reserve: a meta-analysis.

PubMed

Li, S; Tang, X; Peng, L; Luo, Y; Dong, R; Liu, J

2015-05-01

To review the literature on the diagnostic accuracy of CT-derived fractional flow reserve (FFRCT) for the evaluation of myocardial ischaemia in patients with suspected or known coronary artery disease, with invasive fractional flow reserve (FFR) as the reference standard. A PubMed, EMBASE, and Cochrane cross-search was performed. The pooled diagnostic accuracy of FFRCT, with FFR as the reference standard, was primarily analysed, and then compared with that of CT angiography (CTA). The thresholds to diagnose ischaemia were FFR ≤0.80 or CTA ≥50% stenosis. Data extraction, synthesis, and statistical analysis were performed by standard meta-analysis methods. Three multicentre studies (NXT Trial, DISCOVER-FLOW study and DeFACTO study) were included, examining 609 patients and 1050 vessels. The pooled sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), positive likelihood ratio (LR+), negative likelihood ratio (LR-), and diagnostic odds ratio (DOR) for FFRCT were 89% (85-93%), 71% (65-75%), 70% (65-75%), 90% (85-93%), 3.31 (1.79-6.14), 0.16 (0.11-0.23), and 21.21 (9.15-49.15) at the patient-level, and 83% (78-63%), 78% (75-81%), 61% (56-65%), 92% (89-90%), 4.02 (1.84-8.80), 0.22 (0.13-0.35), and 19.15 (5.73-63.93) at the vessel-level. At per-patient analysis, FFRCT has similar sensitivity but improved specificity, PPV, NPV, LR+, LR-, and DOR versus those of CTA. At per-vessel analysis, FFRCT had a slightly lower sensitivity, similar NPV, but improved specificity, PPV, LR+, LR-, and DOR compared with those of CTA. The area under the summary receiver operating characteristic curves for FFRCT was 0.8909 at patient-level and 0.8865 at vessel-level, versus 0.7402 for CTA at patient-level. FFRCT, which was associated with improved diagnostic accuracy versus CTA, is a viable alternative to FFR for detecting coronary ischaemic lesions. Copyright © 2015 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.

The clinical utility and diagnostic performance of magnetic resonance imaging for identification of early and advanced knee osteoarthritis: a systematic review.

PubMed

Quatman, Carmen E; Hettrich, Carolyn M; Schmitt, Laura C; Spindler, Kurt P

2011-07-01

Current diagnostic strategies for detection of structural articular cartilage abnormalities, the earliest structural signs of osteoarthritis, often do not capture the condition until it is too far advanced for the most potential benefit of noninvasive interventions. To systematically review the literature relative to the following questions: (1) Is magnetic resonance imaging (MRI) a valid, sensitive, specific, accurate, and reliable instrument to identify knee articular cartilage abnormalities compared with arthroscopy? (2) Is MRI a sensitive tool that can be utilized to identify early cartilage degeneration? Systematic review. A systematic search was performed in November 2010 using PubMed MEDLINE (from 1966), CINAHL (from 1982), SPORTDiscus (from 1985), SCOPUS (from 1996), and EMBASE (from 1974) databases. Fourteen level I and 13 level II studies were identified that met inclusion criteria and provided information related to diagnostic performance of MRI compared with arthroscopic evaluation. The diagnostic performance of MRI demonstrated a large range of sensitivities, specificities, and accuracies. The sensitivity for identifying articular cartilage abnormalities in the knee joint was reported between 26% and 96%. Specificity and accuracy were reported between 50% and 100% and between 49% and 94%, respectively. The sensitivity, specificity, and accuracy for identifying early osteoarthritis were reported between 0% and 86%, 48% and 95%, and 5% and 94%, respectively. As a result of inconsistencies between imaging techniques and methodological shortcomings of many of the studies, a meta-analysis was not performed, and it was difficult to fully synthesize the information to state firm conclusions about the diagnostic performance of MRI. There is evidence in some MRI protocols that MRI is a relatively valid, sensitive, specific, accurate, and reliable clinical tool for identifying articular cartilage degeneration. Because of heterogeneity of MRI sequences, it is not possible to make definitive conclusions regarding its global clinical utility for guiding diagnosis and treatment strategies. Traumatic sports injuries to the knee may be significant precursor events to early onset of posttraumatic osteoarthritis. Magnetic resonance imaging may aid in early identification of structural injuries to articular cartilage as evidenced by articular cartilage degeneration grading.

The Clinical Utility and Diagnostic Performance of MRI for Identification of Early and Advanced Knee Osteoarthritis: A Systematic Review

PubMed Central

Quatman, Carmen E.; Hettrich, Carolyn M.; Schmitt, Laura C.; Spindler, Kurt P.

2013-01-01

Background Current diagnostic strategies for detection of structural articular cartilage abnormalities, the earliest structural signs of osteoarthritis, often do not capture the condition until it is too far advanced for the most potential benefit of non-invasive interventions. Purpose Systematically review the literature relative to the following questions: (1) Is MRI a valid, sensitive, specific, accurate and reliable instrument to identify knee articular cartilage abnormalities compared to arthroscopy? (2) Is MRI a sensitive tool that can be utilized to identify early cartilage degeneration? Study Design Systematic Review Methods A systematic search was performed in November 2010 using PubMed MEDLINE (from 1966), CINAHL (from 1982), SPORTDiscus (from 1985), and SCOPUS (from 1996) databases. Results Fourteen level I and 13 level II studies were identified that met inclusion criteria and provided information related to diagnostic performance of MRI compared to arthroscopic evaluation. The diagnostic performance of MRI demonstrated a large range of sensitivities, specificities, and accuracies. The sensitivity for identifying articular cartilage abnormalities in the knee joint was reported between 26–96%. Specificity and accuracy was reported between 50–100% and 49–94%, respectively. The sensitivity, specificity, and accuracy for identifying early osteoarthritis were reported between 0–86%, 48–95%, and 5–94%, respectively. As a result of inconsistencies between imaging techniques and methodological shortcomings of many of the studies, a meta-analysis was not performed and it was difficult to fully synthesize the information to state firm conclusions about the diagnostic performance of MRI. Conclusions There is evidence in some MRI protocols that MRI is a relatively valid, sensitive, specific, accurate, and reliable clinical tool for identifying articular cartilage degeneration. Due to heterogeneity of MRI sequences it is not possible to make definitive conclusions regarding its global clinical utility for guiding diagnosis and treatment strategies. Clinical Relevance Traumatic sports injuries to the knee may be significant precursor events to early onset of posttraumatic osteoarthritis. MRI may aid in early identification of structural injuries to articular cartilage as evidenced by articular cartilage degeneration grading. PMID:21730207

CT coronary angiography and exercise ECG in a population with chest pain and low-to-intermediate pre-test likelihood of coronary artery disease.

PubMed

Maffei, Erica; Seitun, Sara; Martini, Chiara; Palumbo, Alessandro; Tarantini, Giuseppe; Berti, Elena; Grilli, Roberto; Tedeschi, Carlo; Messalli, Giancarlo; Guaricci, Andrea; Weustink, Annick C; Mollet, Nico Ra; Cademartiri, Filippo

2010-12-01

To evaluate diagnostic accuracy of exercise ECG (ex-ECG) versus 64-slice CT coronary angiography (CT-CA) for the detection of significant coronary artery stenosis in a population with low-to-intermediate pre-test likelihood of coronary artery disease (CAD). Retrospective single centre. Tertiary academic hospital. 177 consecutive patients (88 men, 89 women, mean age 53.5±7.6 years) with chest pain and low-to-intermediate pre-test likelihood of CAD were retrospectively enrolled. All patients underwent ex-ECG, CT-CA and invasive coronary angiography (ICA). A lumen diameter reduction of ≥50% was considered as significant stenosis for CT-CA. Ex-ECG was classified as positive, negative or non-diagnostic. were compared with ICA. Diagnostic accuracy of CT-CA and ex-ECG was calculated using ICA as the reference standard. A parallel comparative analysis using a cut-off value of 70% for significant lumen reduction was also performed too. Results ICA disclosed an absence of significant stenosis (≥50% luminal narrowing) in 85.3% (151/177) patients, single-vessel disease in 9.0% (16/177) patients and multivessel disease in 5.6% (10/177) patients. Prevalence of obstructive disease at ICA was 14.7% (26/177). Sensitivity, specificity, positive and negative predictive values at the patient level were 100.0%, 98.7%, 92.9%, 100%, respectively, for CT-CA and 46.2%, 16.6%, 8.7%, 64.1%, respectively, for ex-ECG. Agreement between CT-CA and ex-ECG was 20.9%. CT-CA performed equally well in men and women, while ex-ECG had a better performance in men. After considering the cut-off value of 70% for significant stenosis, the difference between CT-CA and ex-ECG remained significant (p<0.01), with a low agreement (21.5%). CT-CA provides optimal diagnostic performance in patients with atypical chest pain and low-to-intermediate risk of CAD. Ex-ECG has poor diagnostic accuracy in this population. Concerns are related to risk of radiation dose versus the benefits of correct disease stratification.

Diagnostic performance of labial minor salivary gland flow measurement for assessment of xerostomia.

PubMed

Satoh-Kuriwada, Shizuko; Iikubo, Masahiro; Shoji, Noriaki; Sakamoto, Maya; Sasano, Takashi

2012-08-01

Minor salivary gland flow rate (MF) has been proposed as a key feature of xerostomia (subjective feeling of dry mouth). To assess its diagnostic performance, MF was compared in xerostomia and control subjects. Sixty-six subjects with xerostomia and 30 controls were enrolled. MF was measured in the lower labial mucosa using the iodine-starch filter paper method. Stimulated whole salivary flow rates were also measured using the gum test (stimulated-WF). Both labial-MF and stimulated-WF were significantly lower in xerostomia subjects than in controls. There was a positive correlation between labial-MF and stimulated-WF in control but not xerostomia subjects. In xerostomia subjects compared to controls, there was a significantly larger reduction in labial-MF than in stimulated-WF. Xerostomia was most accurately diagnosed using a labial-MF cutoff value of 0.25 μL/cm(2)/min. The sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accuracy at this cutoff value were 1.00, 0.87, 0.93, 1.00, and 0.96, respectively. Compared to respective values of 0.64, 1.00, 1.00, 0.56, and 0.75 for stimulated-WF at the traditional cutoff of 1.0 mL/min, these data indicate the higher sensitivity, negative predictive value, and diagnostic accuracy of labial-MF. Xerostomia was more strongly related to reduction of labial-MF than to that of stimulated-WF. Xerostomia was most likely triggered at a labial-MF cut-off value of 0.25 μL/cm(2)/min based on results from the iodine-starch method. Copyright © 2012 Elsevier Ltd. All rights reserved.

Administrative database code accuracy did not vary notably with changes in disease prevalence.

PubMed

van Walraven, Carl; English, Shane; Austin, Peter C

2016-11-01

Previous mathematical analyses of diagnostic tests based on the categorization of a continuous measure have found that test sensitivity and specificity varies significantly by disease prevalence. This study determined if the accuracy of diagnostic codes varied by disease prevalence. We used data from two previous studies in which the true status of renal disease and primary subarachnoid hemorrhage, respectively, had been determined. In multiple stratified random samples from the two previous studies having varying disease prevalence, we measured the accuracy of diagnostic codes for each disease using sensitivity, specificity, and positive and negative predictive value. Diagnostic code sensitivity and specificity did not change notably within clinically sensible disease prevalence. In contrast, positive and negative predictive values changed significantly with disease prevalence. Disease prevalence had no important influence on the sensitivity and specificity of diagnostic codes in administrative databases. Copyright © 2016 Elsevier Inc. All rights reserved.

Feasibility of high-pitch spiral dual-source CT angiography in children with complex congenital heart disease compared to retrospective-gated spiral acquisition.

PubMed

Li, T; Zhao, S; Liu, J; Yang, L; Huang, Z; Li, J; Luo, C; Li, X

2017-10-01

To investigate the use of second-generation dual-source high-pitch computed tomography in obtaining confident diagnostic image quality using a low radiation dose in young patients with congenital heart disease (CHD). From July 2014 to June 2016, 50 consecutive children <4 years with complex CHD underwent electrocardiography (ECG)-triggered dual-source computed tomography (CT). The patients were assigned randomly to two groups: high-pitch (pitch 3.4) spiral dual-source CT acquisition (group A) and retrospectively spiral dual-source CT acquisition (group B). The image quality, diagnostic accuracy, coronary artery origin, course demonstration, and radiation exposure were compared between the two groups. Fifty examinations were performed (group A, 25; group B, 25). There were no significant differences in image quality, diagnostic accuracy, coronary artery origin, and course demonstration between the two groups. The image quality scores were 1.3±0.4 in group A and 1.1±0.3 in group B (p=0.2). The diagnostic accuracy was 100% in both groups. The coronary arteries were traceable in 80% in group A and 84% in group B (p=0.7). A single coronary artery was identified in one case in group A and the left anterior descending (LAD) branch originated from the right coronary artery (RCA) in one case in group B. There were significant differences in the effective doses between the two groups (0.40±0.20 mSv in group A and 2.7±1.0 mSv in group B, p<0.05). Intra-cardiac and extra-cardiac malformation, coronary artery origin, and course malformation can be visualised clearly using a high-pitch ECG-triggered dual-source CT with a low radiation dose and good image quality in patients with CHD. Copyright © 2017 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.

Dual-focus versus conventional magnification endoscopy for the diagnosis of superficial squamous neoplasms in the pharynx and esophagus: a randomized trial.

PubMed

Goda, Kenichi; Dobashi, Akira; Yoshimura, Noboru; Aihara, Hiroyuki; Kato, Masayuki; Sumiyama, Kazuki; Toyoizumi, Hirobumi; Kato, Tomohiro; Saijo, Hiroki; Ikegami, Masahiro; Tajiri, Hisao

2016-04-01

Conventional magnification narrow-band imaging (CM-NBI) endoscopy has demonstrated high diagnostic accuracy for superficial squamous neoplasms in the pharynx and esophagus. This study aimed to evaluate the diagnostic utility of the newly developed dual-focus NBI (DF-NBI) compared with that of CM-NBI. We recruited patients with squamous cell carcinoma (SCC) in the head and neck, or esophagus, or with a history of SCC. The primary endpoint of this prospective controlled non-inferiority trial was the sensitivity of DF-NBI and CM-NBI for detecting superficial carcinoma in the pharynx and esophagus. Secondary endpoints included other diagnostic values and the resolving power of each endoscope. Superficial carcinoma was defined as high grade dysplasia and SCC invading up to the submucosal layer. The study included 93 patients. A total of 28 superficial carcinomas were detected in the pharynx and esophagus. The sensitivities of DF-NBI and CM-NBI for superficial carcinoma were 82 % and 71 %, respectively. The lower limit of the 90 % confidence interval for the difference between the sensitivities exceeded the non-inferiority threshold. The specificity and overall accuracy of DF-NBI vs. CM-NBI were 93 % vs. 90 % and 91 % vs. 86 %, respectively (both non-significant differences). The maximum resolving power of a conventional magnification endoscope was significantly higher than a dual-focus endoscope (7.2 µm vs. 11.6 µm: P < 0.001). The findings indicate the non-inferiority of DF-NBI versus CM-NBI in detecting superficial carcinoma in the pharynx and esophagus. DF-NBI appears to have a resolving power that, although significantly lower, is sufficient to achieve high diagnostic accuracy, comparable to that of CM-NBI.University Hospital Medical Information Network (UMIN, No. 000007585). © Georg Thieme Verlag KG Stuttgart · New York.

Is there any evidence for the validity of diagnostic criteria used for accommodative and nonstrabismic binocular dysfunctions?

PubMed Central

Cacho-Martínez, Pilar; García-Muñoz, Ángel; Ruiz-Cantero, María Teresa

2013-01-01

Purpose To analyze the diagnostic criteria used in the scientific literature published in the past 25 years for accommodative and nonstrabismic binocular dysfunctions and to explore if the epidemiological analysis of diagnostic validity has been used to propose which clinical criteria should be used for diagnostic purposes. Methods We carried out a systematic review of papers on accommodative and non-strabic binocular disorders published from 1986 to 2012 analysing the MEDLINE, CINAHL, PsycINFO and FRANCIS databases. We admitted original articles about diagnosis of these anomalies in any population. We identified 839 articles and 12 studies were included. The quality of included articles was assessed using the QUADAS-2 tool. Results The review shows a wide range of clinical signs and cut-off points between authors. Only 3 studies (regarding accommodative anomalies) assessed diagnostic accuracy of clinical signs. Their results suggest using the accommodative amplitude and monocular accommodative facility for diagnosing accommodative insufficiency and a high positive relative accommodation for accommodative excess. The remaining 9 articles did not analyze diagnostic accuracy, assessing a diagnosis with the criteria the authors considered. We also found differences between studies in the way of considering patients’ symptomatology. 3 studies of 12 analyzed, performed a validation of a symptom survey used for convergence insufficiency. Conclusions Scientific literature reveals differences between authors according to diagnostic criteria for accommodative and nonstrabismic binocular dysfunctions. Diagnostic accuracy studies show that there is only certain evidence for accommodative conditions. For binocular anomalies there is only evidence about a validated questionnaire for convergence insufficiency with no data of diagnostic accuracy. PMID:24646897

Systematic reviews of diagnostic tests in endocrinology: an audit of methods, reporting, and performance.

PubMed

Spencer-Bonilla, Gabriela; Singh Ospina, Naykky; Rodriguez-Gutierrez, Rene; Brito, Juan P; Iñiguez-Ariza, Nicole; Tamhane, Shrikant; Erwin, Patricia J; Murad, M Hassan; Montori, Victor M

2017-07-01

Systematic reviews provide clinicians and policymakers estimates of diagnostic test accuracy and their usefulness in clinical practice. We identified all available systematic reviews of diagnosis in endocrinology, summarized the diagnostic accuracy of the tests included, and assessed the credibility and clinical usefulness of the methods and reporting. We searched Ovid MEDLINE, EMBASE, and Cochrane CENTRAL from inception to December 2015 for systematic reviews and meta-analyses reporting accuracy measures of diagnostic tests in endocrinology. Experienced reviewers independently screened for eligible studies and collected data. We summarized the results, methods, and reporting of the reviews. We performed subgroup analyses to categorize diagnostic tests as most useful based on their accuracy. We identified 84 systematic reviews; half of the tests included were classified as helpful when positive, one-fourth as helpful when negative. Most authors adequately reported how studies were identified and selected and how their trustworthiness (risk of bias) was judged. Only one in three reviews, however, reported an overall judgment about trustworthiness and one in five reported using adequate meta-analytic methods. One in four reported contacting authors for further information and about half included only patients with diagnostic uncertainty. Up to half of the diagnostic endocrine tests in which the likelihood ratio was calculated or provided are likely to be helpful in practice when positive as are one-quarter when negative. Most diagnostic systematic reviews in endocrine lack methodological rigor, protection against bias, and offer limited credibility. Substantial efforts, therefore, seem necessary to improve the quality of diagnostic systematic reviews in endocrinology.

Cost-effectiveness of alternative test strategies for the diagnosis of coronary artery disease.

PubMed

Garber, A M; Solomon, N A

1999-05-04

The appropriate roles for several diagnostic tests for coronary disease are uncertain. To evaluate the cost-effectiveness of alternative approaches to diagnosis of coronary disease. Meta-analysis of the accuracy of alternative diagnostic tests plus decision analysis to assess the health outcomes and costs of alternative diagnostic strategies for patients at intermediate pretest risk for coronary disease. Studies of test accuracy that met inclusion criteria; published information on treatment effectiveness and disease prevalence. Men and women 45, 55, and 65 years of age with a 25% to 75% pretest risk for coronary disease. 30 years. Societal. Diagnostic strategies were initial angiography and initial testing with one of five noninvasive tests--exercise treadmill testing, planar thallium imaging, single-photon emission computed tomography (SPECT), stress echocardiography, and positron emission tomography (PET)--followed by coronary angiography if noninvasive test results were positive. Testing was followed by observation, medical treatment, or revascularization. Life-years, quality-adjusted life-years (QALYs), costs, and costs per QALY. Life expectancy varied little with the initial diagnostic test; for a 55-year-old man, the best-performing test increased life expectancy by 7 more days than the worst-performing test. More sensitive tests increased QALYs more. Echocardiography improved health outcomes and reduced costs relative to stress testing and planar thallium imaging. The incremental cost-effectiveness ratio was $75,000/QALY for SPECT relative to echocardiography and was greater than $640,000 for PET relative to SPECT. Compared with SPECT, immediate angiography had an incremental cost-effectiveness ratio of $94,000/QALY. Qualitative findings varied little with age, sex, pretest probability of disease, or the test indeterminancy rate. Results varied most with sensitivity to severe coronary disease. Echocardiography, SPECT, and immediate angiography are cost-effective alternatives to PET and other diagnostic approaches. Test selection should reflect local variation in test accuracy.