Masch, William R; Cohan, Richard H; Ellis, James H; Dillman, Jonathan R; Rubin, Jonathan M; Davenport, Matthew S
2016-02-01
The purpose of this study was to determine the clinical effectiveness of prospectively reported sonographic twinkling artifact for the diagnosis of renal calculus in patients without known urolithiasis. All ultrasound reports finalized in one health system from June 15, 2011, to June 14, 2014, that contained the words "twinkle" or "twinkling" in reference to suspected renal calculus were identified. Patients with known urolithiasis or lack of a suitable reference standard (unenhanced abdominal CT with ≤ 2.5-mm slice thickness performed ≤ 30 days after ultrasound) were excluded. The sensitivity, specificity, and positive likelihood ratio of sonographic twinkling artifact for the diagnosis of renal calculus were calculated by renal unit and stratified by two additional diagnostic features for calcification (echogenic focus, posterior acoustic shadowing). Eighty-five patients formed the study population. Isolated sonographic twinkling artifact had sensitivity of 0.78 (82/105), specificity of 0.40 (26/65), and a positive likelihood ratio of 1.30 for the diagnosis of renal calculus. Specificity and positive likelihood ratio improved and sensitivity declined when the following additional diagnostic features were present: sonographic twinkling artifact and echogenic focus (sensitivity, 0.61 [64/105]; specificity, 0.65 [42/65]; positive likelihood ratio, 1.72); sonographic twinkling artifact and posterior acoustic shadowing (sensitivity, 0.31 [33/105]; specificity, 0.95 [62/65]; positive likelihood ratio, 6.81); all three features (sensitivity, 0.31 [33/105]; specificity, 0.95 [62/65]; positive likelihood ratio, 6.81). Isolated sonographic twinkling artifact has a high false-positive rate (60%) for the diagnosis of renal calculus in patients without known urolithiasis.
Wang, Lina; Li, Hao; Yang, Zhongyuan; Guo, Zhuming; Zhang, Quan
2015-07-01
This study was designed to assess the efficiency of the serum thyrotropin to thyroglobulin ratio for thyroid nodule evaluation in euthyroid patients. Cross-sectional study. Sun Yat-sen University Cancer Center, State Key Laboratory of Oncology in South China. Retrospective analysis was performed for 400 previously untreated cases presenting with thyroid nodules. Thyroid function was tested with commercially available radioimmunoassays. The receiver operating characteristic curves were constructed to determine cutoff values. The efficacy of the thyrotropin:thyroglobulin ratio and thyroid-stimulating hormone for thyroid nodule evaluation was evaluated in terms of sensitivity, specificity, positive predictive value, positive likelihood ratio, negative likelihood ratio, and odds ratio. In receiver operating characteristic curve analysis, the area under the curve was 0.746 for the thyrotropin:thyroglobulin ratio and 0.659 for thyroid-stimulating hormone. With a cutoff point value of 24.97 IU/g for the thyrotropin:thyroglobulin ratio, the sensitivity, specificity, positive predictive value, positive likelihood ratio, and negative likelihood ratio were 78.9%, 60.8%, 75.5%, 2.01, and 0.35, respectively. The odds ratio for the thyrotropin:thyroglobulin ratio indicating malignancy was 5.80. With a cutoff point value of 1.525 µIU/mL for thyroid-stimulating hormone, the sensitivity, specificity, positive predictive value, positive likelihood ratio, and negative likelihood ratio were 74.0%, 53.2%, 70.8%, 1.58, and 0.49, respectively. The odds ratio indicating malignancy for thyroid-stimulating hormone was 3.23. Increasing preoperative serum thyrotropin:thyroglobulin ratio is a risk factor for thyroid carcinoma, and the correlation of the thyrotropin:thyroglobulin ratio to malignancy is higher than that for serum thyroid-stimulating hormone. © American Academy of Otolaryngology—Head and Neck Surgery Foundation 2015.
Ran, Li; Zhao, Wenli; Zhao, Ye; Bu, Huaien
2017-07-01
Contrast-enhanced ultrasound (CEUS) is considered a novel method for diagnosing pancreatic cancer, but currently, there is no conclusive evidence of its accuracy. Using CEUS in discriminating between pancreatic carcinoma and other pancreatic lesions, we aimed to evaluate the diagnostic accuracy of CEUS in predicting pancreatic tumours. Relevant studies were selected from the PubMed, Cochrane Library, Elsevier, CNKI, VIP, and WANFANG databases dating from January 2006 to May 2017. The following terms were used as keywords: "pancreatic cancer" OR "pancreatic carcinoma," "contrast-enhanced ultrasonography" OR "contrast-enhanced ultrasound" OR "CEUS," and "diagnosis." The selection criteria are as follows: pancreatic carcinomas diagnosed by CEUS while the main reference standard was surgical pathology or biopsy (if it involved a clinical diagnosis, particular criteria emphasized); SonoVue or Levovist was the contrast agent; true positive, false positive, false negative, and true negative rates were obtained or calculated to construct the 2 × 2 contingency table; English or Chinese articles; at least 20 patients were enrolled in each group. The Quality Assessment for Studies of Diagnostic Accuracy was employed to evaluate the quality of articles. Pooled sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, diagnostic odds ratio, summary receiver-operating characteristic curves, and the area under curve were evaluated to estimate the overall diagnostic efficiency. Pooled sensitivity, specificity, positive likelihood ratio, and negative likelihood ratio with 95% confidence intervals (CIs) were calculated with fixed-effect models. Eight of 184 records were eligible for a meta-analysis after independent scrutinization by 2 reviewers. The pooled sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, and diagnostic odds ratios were 0.86 (95% CI 0.81-0.90), 0.75 (95% CI 0.68-0.82), 3.56 (95% CI 2.64-4.78), 0.19 (95% CI 0.13-0.27), and 22.260 (95% CI 8.980-55.177), respectively. The area under the SROC curve was 0.9088. CEUS has a satisfying pooled sensitivity and specificity for discriminating pancreatic cancer from other pancreatic lesions.
PHYSICAL EXAMINATIONS FOR DIAGNOSING MENISCAL INJURIES: CORRELATION WITH SURGICAL FINDINGS
Gobbo, Ricardo da Rocha; Rangel, Victor de Oliveira; Karam, Francisco Consoli; Pires, Luiz Antônio Simões
2015-01-01
Objective: A set of five maneuvers for meniscal injuries (McMurray, Apley, Childress and Steinmann 1 and 2) was evaluated and their sensitivity, specificity, accuracy and likelihood were calculated. The same methods were applied to each test individually. Methods: One hundred and fifty-two patients of both sexes who were going to undergo videoarthroscopy on the knee were examined blindly by one of five residents at this hospital, without knowledge of the clinical data and why the patient was going to undergo an operation. This examination was conducted immediately before the videoarthroscopy and its results were recorded in an electronic spreadsheet. The set of maneuvers was considered positive when one was positive. In the individual analysis, it was enough for the test to be positive. Results: The analysis showed that the set of five meniscal tests presented sensitivity of 89%, specificity of 42%, accuracy of 75%, positive likelihood of 1.53 and negative likelihood of 0.26. Individually, the tests presented accuracy of between 48% and 53%. Conclusion: The set of maneuvers for meniscal injuries presented a good accuracy and significant value, especially for ruling out injury. Individually, the tests had less diagnostic value, although the Apley test had better specificity. PMID:27047833
Use of Bayes theorem to correct size-specific sampling bias in growth data.
Troynikov, V S
1999-03-01
The bayesian decomposition of posterior distribution was used to develop a likelihood function to correct bias in the estimates of population parameters from data collected randomly with size-specific selectivity. Positive distributions with time as a parameter were used for parametrization of growth data. Numerical illustrations are provided. The alternative applications of the likelihood to estimate selectivity parameters are discussed.
Urabe, Naohisa; Sano, Go; Suzuki, Junko; Hebisawa, Akira; Nakamura, Yasuhiko; Koyama, Kazuya; Ishii, Yoshikazu; Tateda, Kazuhiro; Homma, Sakae
2017-01-01
ABSTRACT We evaluated the usefulness of an Aspergillus galactomannan (GM) test, a β-d-glucan (βDG) test, and two different Aspergillus PCR assays of bronchoalveolar lavage fluid (BALF) samples for the diagnosis of chronic pulmonary aspergillosis (CPA). BALF samples from 30 patients with and 120 patients without CPA were collected. We calculated the sensitivity, specificity, positive predictive value, negative predictive value, positive likelihood ratio, negative likelihood ratio, and diagnostic odds ratio for each test individually and in combination with other tests. The optical density index values, as determined by receiver operating characteristic analysis, for the diagnosis of CPA were 0.5 and 100 for GM and βDG testing of BALF, respectively. The sensitivity and specificity of the GM test, βDG test, and PCR assays 1 and 2 were 77.8% and 90.0%, 77.8% and 72.5%, 86.7% and 84.2%, and 66.7% and 94.2%, respectively. A comparison of the PCR assays showed that PCR assay 1 had a better sensitivity, a better negative predictive value, and a better negative likelihood ratio and PCR assay 2 had a better specificity, a better positive predictive value, and a better positive likelihood ratio. The combination of the GM and βDG tests had the highest diagnostic odds ratio. The combination of the GM and βDG tests on BALF was more useful than any single test for diagnosing CPA. PMID:28330887
A likelihood ratio test for evolutionary rate shifts and functional divergence among proteins
Knudsen, Bjarne; Miyamoto, Michael M.
2001-01-01
Changes in protein function can lead to changes in the selection acting on specific residues. This can often be detected as evolutionary rate changes at the sites in question. A maximum-likelihood method for detecting evolutionary rate shifts at specific protein positions is presented. The method determines significance values of the rate differences to give a sound statistical foundation for the conclusions drawn from the analyses. A statistical test for detecting slowly evolving sites is also described. The methods are applied to a set of Myc proteins for the identification of both conserved sites and those with changing evolutionary rates. Those positions with conserved and changing rates are related to the structures and functions of their proteins. The results are compared with an earlier Bayesian method, thereby highlighting the advantages of the new likelihood ratio tests. PMID:11734650
Recognition of depressive symptoms by physicians.
Henriques, Sergio Gonçalves; Fráguas, Renério; Iosifescu, Dan V; Menezes, Paulo Rossi; Lucia, Mara Cristina Souza de; Gattaz, Wagner Farid; Martins, Milton Arruda
2009-01-01
To investigate the recognition of depressive symptoms of major depressive disorder (MDD) by general practitioners. MDD is underdiagnosed in medical settings, possibly because of difficulties in the recognition of specific depressive symptoms. A cross-sectional study of 316 outpatients at their first visit to a teaching general hospital. We evaluated the performance of 19 general practitioners using Primary Care Evaluation of Mental Disorders (PRIME-MD) to detect depressive symptoms and compared them to 11 psychiatrists using Structured Clinical Interview Axis I Disorders, Patient Version (SCID I/P). We measured likelihood ratios, sensitivity, specificity, and false positive and false negative frequencies. The lowest positive likelihood ratios were for psychomotor agitation/retardation (1.6) and fatigue (1.7), mostly because of a high rate of false positive results. The highest positive likelihood ratio was found for thoughts of suicide (8.5). The lowest sensitivity, 61.8%, was found for impaired concentration. The sensitivity for worthlessness or guilt in patients with medical illness was 67.2% (95% CI, 57.4-76.9%), which is significantly lower than that found in patients without medical illness, 91.3% (95% CI, 83.2-99.4%). Less adequately identified depressive symptoms were both psychological and somatic in nature. The presence of a medical illness may decrease the sensitivity of recognizing specific depressive symptoms. Programs for training physicians in the use of diagnostic tools should consider their performance in recognizing specific depressive symptoms. Such procedures could allow for the development of specific training to aid in the detection of the most misrecognized depressive symptoms.
Ebell, Mark H; Call, Marlene; Shinholser, JoAnna; Gardner, Jack
2016-04-12
Early, accurate diagnosis of infectious mononucleosis can help clinicians target treatment, avoid antibiotics, and provide an accurate prognosis. To systematically review the literature regarding the value of the clinical examination and white blood cell count for the diagnosis of mononucleosis. The databases of PubMed (from 1966-2016) and EMBASE (from 1947-2015) were searched and a total of 670 articles and abstracts were reviewed for eligibility. Eleven studies were included that reported data sufficient to calculate sensitivity, specificity, or both for clinical examination findings and white blood cell count parameters compared with a valid reference standard. Data were abstracted from each article by at least 2 reviewers, with discrepancies reconciled by consensus. Clinical findings evaluated in only 1 study are reported with sensitivity, specificity, likelihood ratio (LR), and 95% confidence interval, which were calculated from the available data. Findings evaluated in only 2 studies were summarized with their range, findings evaluated in 3 studies were summarized with a univariate random-effects summary, and findings evaluated in 4 or more studies were summarized with a bivariate random-effects meta-analysis. Sensitivity, specificity, and LRs for the diagnosis of mononucleosis. Mononucleosis is most commonly present among patients aged 5 to 25 years (especially those aged 16-20 years, among whom approximately 1 in 13 patients presenting with sore throat has mononucleosis). The likelihood of mononucleosis is reduced with the absence of any lymphadenopathy (summary sensitivity, 0.91; positive LR range, 0.23-0.44), whereas the likelihood increases with the presence of posterior cervical adenopathy (summary specificity, 0.87; positive LR, 3.1 [95% CI, 1.6-5.9]), inguinal or axillary adenopathy (specificity range, 0.82-0.91; positive LR range, 3.0-3.1), palatine petechiae (specificity, 0.95; positive LR, 5.3 [95% CI, 2.1-13]), and splenomegaly (specificity range, 0.71-0.99; positive LR range, 1.9-6.6). Symptoms are of limited value for the diagnosis of mononucleosis; sore throat and fatigue are sensitive (range, 0.81-0.83) but nonspecific. The presence of atypical lymphocytosis significantly increases the likelihood of mononucleosis (summary LR, 11.4 [95% CI, 2.7-35] for atypical lymphocytes ≥10%, 26 [95% CI, 9.6-68] for those with 20%, and 50 [95% CI, 38-64] for those with 40%). The combination of a patient having greater than 50% lymphocytes and greater than 10% atypical lymphocytes also is useful (specificity, 0.99; positive LR, 54 [95% CI, 8.4-189]). In adolescent and adult patients presenting with sore throat, the presence of posterior cervical, inguinal or axillary adenopathy, palatine petechiae, splenomegaly, or atypical lymphocytosis is associated with an increased likelihood of mononucleosis.
Beyond valence in the perception of likelihood: the role of emotion specificity.
DeSteno, D; Petty, R E; Wegener, D T; Rucker, D D
2000-03-01
Positive and negative moods have been shown to increase likelihood estimates of future events matching these states in valence (e.g., E. J. Johnson & A. Tversky, 1983). In the present article, 4 studies provide evidence that this congruency bias (a) is not limited to valence but functions in an emotion-specific manner, (b) derives from the informational value of emotions, and (c) is not the inevitable outcome of likelihood assessment under heightened emotion. Specifically, Study 1 demonstrates that sadness and anger, 2 distinct, negative emotions, differentially bias likelihood estimates of sad and angering events. Studies 2 and 3 replicate this finding in addition to supporting an emotion-as-information (cf. N. Schwarz & G. L. Clore, 1983), as opposed to a memory-based, mediating process for the bias. Finally, Study 4 shows that when the source of the emotion is salient, a reversal of the bias can occur given greater cognitive effort aimed at accuracy.
Van Hoeyveld, Erna; Nickmans, Silvie; Ceuppens, Jan L; Bossuyt, Xavier
2015-10-23
Cut-off values and predictive values are used for the clinical interpretation of specific IgE antibody results. However, cut-off levels are not well defined, and predictive values are dependent on the prevalence of disease. The objective of this study was to document clinically relevant diagnostic accuracy of specific IgE for inhalant allergens (grass pollen and birch pollen) based on test result interval-specific likelihood ratios. Likelihood ratios are independent of the prevalence and allow to provide diagnostic accuracy information for test result intervals. In a prospective study we included consecutive adult patients presenting at an allergy clinic with complaints of rhinitis or rhinoconjunctivitis. The standard for diagnosis was a suggestive clinical history of grass or birch pollen allergy and a positive skin test. Specific IgE was determined with the ImmunoCAP Fluorescence Enzyme Immuno-Assay. We established specific IgE test result interval related likelihood ratios for clinical allergy to inhalant allergens (grass pollen, rPhl p 1,5, birch pollen, rBet v 1). The likelihood ratios for allergy increased with increasing specific IgE antibody levels. The likelihood ratio was <0.03 for specific IgE <0.1 kU/L, between 0.1 and 1.4 for specific IgE between 0.1 kU/L and 0.35 kU/L, between 1.4 and 4.2 for specific IgE between 0.35 kU/L and 3.5 kU/L, >6.3 for specific IgE>0.7, and very high (∞) for specific IgE >3.5 kU/L. Test result interval specific likelihood ratios provide a useful tool for the interpretation of specific IgE test results for inhalant allergens. Copyright © 2015 Elsevier B.V. All rights reserved.
Urabe, Naohisa; Sakamoto, Susumu; Sano, Go; Suzuki, Junko; Hebisawa, Akira; Nakamura, Yasuhiko; Koyama, Kazuya; Ishii, Yoshikazu; Tateda, Kazuhiro; Homma, Sakae
2017-06-01
We evaluated the usefulness of an Aspergillus galactomannan (GM) test, a β-d-glucan (βDG) test, and two different Aspergillus PCR assays of bronchoalveolar lavage fluid (BALF) samples for the diagnosis of chronic pulmonary aspergillosis (CPA). BALF samples from 30 patients with and 120 patients without CPA were collected. We calculated the sensitivity, specificity, positive predictive value, negative predictive value, positive likelihood ratio, negative likelihood ratio, and diagnostic odds ratio for each test individually and in combination with other tests. The optical density index values, as determined by receiver operating characteristic analysis, for the diagnosis of CPA were 0.5 and 100 for GM and βDG testing of BALF, respectively. The sensitivity and specificity of the GM test, βDG test, and PCR assays 1 and 2 were 77.8% and 90.0%, 77.8% and 72.5%, 86.7% and 84.2%, and 66.7% and 94.2%, respectively. A comparison of the PCR assays showed that PCR assay 1 had a better sensitivity, a better negative predictive value, and a better negative likelihood ratio and PCR assay 2 had a better specificity, a better positive predictive value, and a better positive likelihood ratio. The combination of the GM and βDG tests had the highest diagnostic odds ratio. The combination of the GM and βDG tests on BALF was more useful than any single test for diagnosing CPA. Copyright © 2017 American Society for Microbiology.
Li, Zhanzhan; Zhou, Qin; Li, Yanyan; Yan, Shipeng; Fu, Jun; Huang, Xinqiong; Shen, Liangfang
2017-02-28
We conducted a meta-analysis to evaluate the diagnostic values of mean cerebral blood volume for recurrent and radiation injury in glioma patients. We performed systematic electronic searches for eligible study up to August 8, 2016. Bivariate mixed effects models were used to estimate the combined sensitivity, specificity, positive likelihood ratios, negative likelihood ratios, diagnostic odds ratios and their 95% confidence intervals (CIs). Fifteen studies with a total number of 576 participants were enrolled. The pooled sensitivity and specificity of diagnostic were 0.88 (95%CI: 0.82-0.92) and 0.85 (95%CI: 0.68-0.93). The pooled positive likelihood ratio is 5.73 (95%CI: 2.56-12.81), negative likelihood ratio is 0.15 (95%CI: 0.10-0.22), and the diagnostic odds ratio is 39.34 (95%CI:13.96-110.84). The summary receiver operator characteristic is 0.91 (95%CI: 0.88-0.93). However, the Deek's plot suggested publication bias may exist (t=2.30, P=0.039). Mean cerebral blood volume measurement methods seems to be very sensitive and highly specific to differentiate recurrent and radiation injury in glioma patients. The results should be interpreted with caution because of the potential bias.
Newman, Phil; Adams, Roger; Waddington, Gordon
2012-09-01
To examine the relationship between two clinical test results and future diagnosis of (Medial Tibial Stress Syndrome) MTSS in personnel at a military trainee establishment. Data from a preparticipation musculoskeletal screening test performed on 384 Australian Defence Force Academy Officer Cadets were compared against 693 injuries reported by 326 of the Officer Cadets in the following 16 months. Data were held in an Injury Surveillance database and analysed using χ² and Fisher's Exact tests, and Receiver Operating Characteristic Curve analysis. Diagnosis of MTSS, confirmed by an independent blinded health practitioner. Both the palpation and oedema clinical tests were each found to be significant predictors for later onset of MTSS. Specifically: Shin palpation test OR 4.63, 95% CI 2.5 to 8.5, Positive Likelihood Ratio 3.38, Negative Likelihood Ratio 0.732, Pearson χ² p<0.001; Shin oedema test OR 76.1 95% CI 9.6 to 602.7, Positive Likelihood Ratio 7.26, Negative Likelihood Ratio 0.095, Fisher's Exact p<0.001; Combined Shin Palpation Test and Shin Oedema Test Positive Likelihood Ratio 7.94, Negative Likelihood Ratio <0.001, Fisher's Exact p<0.001. Female gender was found to be an independent risk factor (OR 2.97, 95% CI 1.66 to 5.31, Positive Likelihood Ratio 2.09, Negative Likelihood Ratio 0.703, Pearson χ² p<0.001) for developing MTSS. The tests for MTSS employed here are components of a normal clinical examination used to diagnose MTSS. This paper confirms that these tests and female gender can also be confidently applied in predicting those in an asymptomatic population who are at greater risk of developing MTSS symptoms with activity at some point in the future.
[Waist-to-height ratio is an indicator of metabolic risk in children].
Valle-Leal, Jaime; Abundis-Castro, Leticia; Hernández-Escareño, Juan; Flores-Rubio, Salvador
2016-01-01
Abdominal fat, particularly visceral, is associated with a high risk of metabolic complications. The waist-height ratio (WHtR) is used to assess abdominal fat in individuals of all ages. To determine the ability of the waist-to-height ratio to detect metabolic risk in mexican schoolchildren. A study was conducted on children between 6 and 12 years. Obesity was diagnosed as a body mass index (BMI) ≥ 85th percentile, and an ICE ≥0.5 was considered abdominal obesity. Blood levels of glucose, cholesterol and triglycerides were measured. The sensitivity, specificity, positive predictive and negative value, area under curve, the positive likelihood ratio and negative likelihood ratio of the WHtR and BMI were calculated in order to identify metabolic alterations. WHtR and BMI were compared to determine which had the best diagnostic efficiency. Of the 223 children included in the study, 51 had hypertriglyceridaemia, 27 with hypercholesterolaemia, and 9 with hyperglycaemia. On comparing the diagnostic efficiency of WHtR with that of BMI, there was a sensitivity of 100% vs. 56% for hyperglycaemia, 93 vs. 70% for cholesterol, and 76 vs. 59% for hypertriglyceridaemia. The specificity, negative predictive value, positive predictive value, positive likelihood ratio, negative likelihood ratio, and area under curve were also higher for WHtR. The WHtR is a more efficient indicator than BMI in identifying metabolic risk in mexican school-age. Copyright © 2015 Sociedad Chilena de Pediatría. Publicado por Elsevier España, S.L.U. All rights reserved.
The effect of social cues on marketing decisions
NASA Astrophysics Data System (ADS)
Hentschel, H. G. E.; Pan, Jiening; Family, Fereydoon; Zhang, Zhenyu; Song, Yiping
2012-02-01
We address the question as to what extent individuals, when given information in marketing polls on the decisions made by the previous Nr individuals questioned, are likely to change their original choices. The processes can be formulated in terms of a Cost function equivalent to a Hamiltonian, which depends on the original likelihood of an individual making a positive decision in the absence of social cues p0; the strength of the social cue J; and memory size Nr. We find both positive and negative herding effects are significant. Specifically, if p0>1/2 social cues enhance positive decisions, while for p0<1/2 social cues reduce the likelihood of a positive decision.
Bazot, Marc; Daraï, Emile
2018-03-01
The aim of the present review, conducted according to PRISMA statement recommendations, was to evaluate the contribution of transvaginal sonography (TVS) and magnetic resonance imaging (MRI) to diagnose adenomyosis. Although there is a lack of consensus on adenomyosis classification, three subtypes are described, internal, external adenomyosis, and adenomyomas. Using TVS, whatever the subtype, pooled sensitivities, pooled specificities, and pooled positive likelihood ratios are 0.72-0.82, 0.85-0.81, and 4.67-3.7, respectively, but with a high heterogeneity between the studies. MRI has a pooled sensitivity of 0.77, specificity of 0.89, positive likelihood ratio of 6.5, and negative likelihood ratio of 0.2 for all subtypes. Our results suggest that MRI is more useful than TVS in the diagnosis of adenomyosis. Further studies are required to determine the performance of direct signs (cystic component) and indirect signs (characteristics of junctional zone) to avoid misdiagnosis of adenomyosis. Copyright © 2018 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.
Haidar, Ziad A; Papanna, Ramesha; Sibai, Baha M; Tatevian, Nina; Viteri, Oscar A; Vowels, Patricia C; Blackwell, Sean C; Moise, Kenneth J
2017-08-01
Traditionally, 2-dimensional ultrasound parameters have been used for the diagnosis of a suspected morbidly adherent placenta previa. More objective techniques have not been well studied yet. The objective of the study was to determine the ability of prenatal 3-dimensional power Doppler analysis of flow and vascular indices to predict the morbidly adherent placenta objectively. A prospective cohort study was performed in women between 28 and 32 gestational weeks with known placenta previa. Patients underwent a two-dimensional gray-scale ultrasound that determined management decisions. 3-Dimensional power Doppler volumes were obtained during the same examination and vascular, flow, and vascular flow indices were calculated after manual tracing of the viewed placenta in the sweep; data were blinded to obstetricians. Morbidly adherent placenta was confirmed by histology. Severe morbidly adherent placenta was defined as increta/percreta on histology, blood loss >2000 mL, and >2 units of PRBC transfused. Sensitivities, specificities, predictive values, and likelihood ratios were calculated. Student t and χ 2 tests, logistic regression, receiver-operating characteristic curves, and intra- and interrater agreements using Kappa statistics were performed. The following results were found: (1) 50 women were studied: 23 had morbidly adherent placenta, of which 12 (52.2%) were severe morbidly adherent placenta; (2) 2-dimensional parameters diagnosed morbidly adherent placenta with a sensitivity of 82.6% (95% confidence interval, 60.4-94.2), a specificity of 88.9% (95% confidence interval, 69.7-97.1), a positive predictive value of 86.3% (95% confidence interval, 64.0-96.4), a negative predictive value of 85.7% (95% confidence interval, 66.4-95.3), a positive likelihood ratio of 7.4 (95% confidence interval, 2.5-21.9), and a negative likelihood ratio of 0.2 (95% confidence interval, 0.08-0.48); (3) mean values of the vascular index (32.8 ± 7.4) and the vascular flow index (14.2 ± 3.8) were higher in morbidly adherent placenta (P < .001); (4) area under the receiver-operating characteristic curve for the vascular and vascular flow indices were 0.99 and 0.97, respectively; (5) the vascular index ≥21 predicted morbidly adherent placenta with a sensitivity and a specificity of 95% (95% confidence interval, 88.2-96.9) and 91%, respectively (95% confidence interval, 87.5-92.4), 92% positive predictive value (95% confidence interval, 85.5-94.3), 90% negative predictive value (95% confidence interval, 79.9-95.3), positive likelihood ratio of 10.55 (95% confidence interval, 7.06-12.75), and negative likelihood ratio of 0.05 (95% confidence interval, 0.03-0.13); and (6) for the severe morbidly adherent placenta, 2-dimensional ultrasound had a sensitivity of 33.3% (95% confidence interval, 11.3-64.6), a specificity of 81.8% (95% confidence interval, 47.8-96.8), a positive predictive value of 66.7% (95% confidence interval, 24.1-94.1), a negative predictive value of 52.9% (95% confidence interval, 28.5-76.1), a positive likelihood ratio of 1.83 (95% confidence interval, 0.41-8.11), and a negative likelihood ratio of 0.81 (95% confidence interval, 0.52-1.26). A vascular index ≥31 predicted the diagnosis of a severe morbidly adherent placenta with a 100% sensitivity (95% confidence interval, 72-100), a 90% specificity (95% confidence interval, 81.7-93.8), an 88% positive predictive value (95% confidence interval, 55.0-91.3), a 100% negative predictive value (95% confidence interval, 90.9-100), a positive likelihood ratio of 10.0 (95% confidence interval, 3.93-16.13), and a negative likelihood ratio of 0 (95% confidence interval, 0-0.34). Intrarater and interrater agreements were 94% (P < .001) and 93% (P < .001), respectively. The vascular index accurately predicts the morbidly adherent placenta in patients with placenta previa. In addition, 3-dimensional power Doppler vascular and vascular flow indices were more predictive of severe cases of morbidly adherent placenta compared with 2-dimensional ultrasound. This objective technique may limit the variations in diagnosing morbidly adherent placenta because of the subjectivity of 2-dimensional ultrasound interpretations. Copyright © 2017 Elsevier Inc. All rights reserved.
The Diagnostic Accuracy of Cytology for the Diagnosis of Hepatobiliary and Pancreatic Cancers.
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.
Validation of the diagnostic score for acute lower abdominal pain in women of reproductive age.
Jearwattanakanok, Kijja; Yamada, Sirikan; Suntornlimsiri, Watcharin; Smuthtai, Waratsuda; Patumanond, Jayanton
2014-01-01
Background. The differential diagnoses of acute appendicitis obstetrics, and gynecological conditions (OB-GYNc) or nonspecific abdominal pain in young adult females with lower abdominal pain are clinically challenging. The present study aimed to validate the recently developed clinical score for the diagnosis of acute lower abdominal pain in female of reproductive age. Method. Medical records of reproductive age women (15-50 years) who were admitted for acute lower abdominal pain were collected. Validation data were obtained from patients admitted during a different period from the development data. Result. There were 302 patients in the validation cohort. For appendicitis, the score had a sensitivity of 91.9%, a specificity of 79.0%, and a positive likelihood ratio of 4.39. The sensitivity, specificity, and positive likelihood ratio in diagnosis of OB-GYNc were 73.0%, 91.6%, and 8.73, respectively. The areas under the receiver operating curves (ROC), the positive likelihood ratios, for appendicitis and OB-GYNc in the validation data were not significantly different from the development data, implying similar performances. Conclusion. The clinical score developed for the diagnosis of acute lower abdominal pain in female of reproductive age may be applied to guide differential diagnoses in these patients.
Jindal, Shveta; Dada, Tanuj; Sreenivas, V; Gupta, Viney; Sihota, Ramanjit; Panda, Anita
2010-01-01
Purpose: To compare the diagnostic performance of the Heidelberg retinal tomograph (HRT) glaucoma probability score (GPS) with that of Moorfield’s regression analysis (MRA). Materials and Methods: The study included 50 eyes of normal subjects and 50 eyes of subjects with early-to-moderate primary open angle glaucoma. Images were obtained by using HRT version 3.0. Results: The agreement coefficient (weighted k) for the overall MRA and GPS classification was 0.216 (95% CI: 0.119 – 0.315). The sensitivity and specificity were evaluated using the most specific (borderline results included as test negatives) and least specific criteria (borderline results included as test positives). The MRA sensitivity and specificity were 30.61 and 98% (most specific) and 57.14 and 98% (least specific). The GPS sensitivity and specificity were 81.63 and 73.47% (most specific) and 95.92 and 34.69% (least specific). The MRA gave a higher positive likelihood ratio (28.57 vs. 3.08) and the GPS gave a higher negative likelihood ratio (0.25 vs. 0.44).The sensitivity increased with increasing disc size for both MRA and GPS. Conclusions: There was a poor agreement between the overall MRA and GPS classifications. GPS tended to have higher sensitivities, lower specificities, and lower likelihood ratios than the MRA. The disc size should be taken into consideration when interpreting the results of HRT, as both the GPS and MRA showed decreased sensitivity for smaller discs and the GPS showed decreased specificity for larger discs. PMID:20952832
Husain, Shahid; Kwak, Eun Jeong; Obman, Asia; Wagener, Marilyn M; Kusne, Shimon; Stout, Janet E; McCurry, Kenneth R; Singh, Nina
2004-05-01
The clinical utility of Platelia trade mark Aspergillus galactomannan antigen for the early diagnosis of invasive aspergillosis was prospectively assessed in 70 consecutive lung transplant recipients. Sera were collected twice weekly and tested for galactomannan. Invasive aspergillosis was documented in 17.1% (12/70) of the patients. Using the generalized estimating equation model, at the cutoff value of >or= 0.5, the sensitivity of the test was 30%, specificity 93% with positive and negative likelihood ratios of 4.2 and 0.75, respectively. Increasing the cutoff value to >or= 0.66 yielded a sensitivity of 30%, specificity of 95%, and positive and negative likelihood ratios of 5.5 and 0.74. A total of 14 patients had false-positive tests, including nine who had cystic fibrosis or chronic obstructive pulmonary disease. False-positive tests occurred within 3 days of transplantation in 43% (6/14) of the patients, and within 7 days in 64% (9/14). Thus, the test demonstrated excellent specificity, but a low sensitivity for the diagnosis of aspergillosis in this patient population. Patients with cystic fibrosis or chronic obstructive pulmonary disease may transiently have a positive test in the early post-transplant period.
Chen, Yong; Liu, Yulun; Ning, Jing; Cormier, Janice; Chu, Haitao
2014-01-01
Systematic reviews of diagnostic tests often involve a mixture of case-control and cohort studies. The standard methods for evaluating diagnostic accuracy only focus on sensitivity and specificity and ignore the information on disease prevalence contained in cohort studies. Consequently, such methods cannot provide estimates of measures related to disease prevalence, such as population averaged or overall positive and negative predictive values, which reflect the clinical utility of a diagnostic test. In this paper, we propose a hybrid approach that jointly models the disease prevalence along with the diagnostic test sensitivity and specificity in cohort studies, and the sensitivity and specificity in case-control studies. In order to overcome the potential computational difficulties in the standard full likelihood inference of the proposed hybrid model, we propose an alternative inference procedure based on the composite likelihood. Such composite likelihood based inference does not suffer computational problems and maintains high relative efficiency. In addition, it is more robust to model mis-specifications compared to the standard full likelihood inference. We apply our approach to a review of the performance of contemporary diagnostic imaging modalities for detecting metastases in patients with melanoma. PMID:25897179
Ma, Chunming; Liu, Yue; Lu, Qiang; Lu, Na; Liu, Xiaoli; Tian, Yiming; Wang, Rui; Yin, Fuzai
2016-02-01
The blood pressure-to-height ratio (BPHR) has been shown to be an accurate index for screening hypertension in children and adolescents. The aim of the present study was to perform a meta-analysis to assess the performance of BPHR for the assessment of hypertension. Electronic and manual searches were performed to identify studies of the BPHR. After methodological quality assessment and data extraction, pooled estimates of the sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, diagnostic odds ratio, area under the receiver operating characteristic curve and summary receiver operating characteristics were assessed systematically. The extent of heterogeneity for it was assessed. Six studies were identified for analysis. The pooled sensitivity, specificity, positive likelihood ratio, negative likelihood ratio and diagnostic odds ratio values of BPHR, for assessment of hypertension, were 96% [95% confidence interval (CI)=0.95-0.97], 90% (95% CI=0.90-0.91), 10.68 (95% CI=8.03-14.21), 0.04 (95% CI=0.03-0.07) and 247.82 (95% CI=114.50-536.34), respectively. The area under the receiver operating characteristic curve was 0.9472. The BPHR had higher diagnostic accuracies for identifying hypertension in children and adolescents.
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.
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.
Durand, Eric; Bauer, Fabrice; Mansencal, Nicolas; Azarine, Arshid; Diebold, Benoit; Hagege, Albert; Perdrix, Ludivine; Gilard, Martine; Jobic, Yannick; Eltchaninoff, Hélène; Bensalah, Mourad; Dubourg, Benjamin; Caudron, Jérôme; Niarra, Ralph; Chatellier, Gilles; Dacher, Jean-Nicolas; Mousseaux, Elie
2017-08-15
To perform a head-to-head comparison of coronary CT angiography (CCTA) and dobutamine-stress echocardiography (DSE) in patients presenting recent chest pain when troponin and ECG are negative. Two hundred seventeen patients with recent chest pain, normal ECG findings, and negative troponin were prospectively included in this multicenter study and were scheduled for CCTA and DSE. Invasive coronary angiography (ICA), was performed in patients when either DSE or CCTA was considered positive or when both were non-contributive or in case of recurrent chest pain during 6month follow-up. The presence of coronary artery stenosis was defined as a luminal obstruction >50% diameter in any coronary segment at ICA. ICA was performed in 75 (34.6%) patients. Coronary artery stenosis was identified in 37 (17%) patients. For CCTA, the sensitivity was 96.9% (95% CI 83.4-99.9), specificity 48.3% (29.4-67.5), positive likelihood ratio 2.06 (95% CI 1.36-3.11), and negative likelihood ratio 0.07 (95% CI 0.01-0.52). The sensitivity of DSE was 51.6% (95% CI 33.1-69.9), specificity 46.7% (28.3-65.7), positive likelihood ratio 1.03 (95% CI 0.62-1.72), and negative likelihood ratio 1.10 (95% CI 0.63-1.93). The CCTA: DSE ratio of true-positive and false-positive rates was 1.70 (95% CI 1.65-1.75) and 1.00 (95% CI 0.91-1.09), respectively, when non-contributive CCTA and DSE were both considered positive. Only one missed acute coronary syndrome was observed at six months. CCTA has higher diagnostic performance than DSE in the evaluation of patients with recent chest pain, normal ECG findings, and negative troponine to exclude coronary artery disease. Copyright © 2017. Published by Elsevier B.V.
Brophy, Robert H; Lyman, Stephen; Chehab, Eric L; Barnes, Ronnie P; Rodeo, Scott A; Warren, Russell F
2009-04-01
The National Football League holds an annual combine where individual teams evaluate college football players The abstract goes here and covers two columns. likely to be drafted for physical skills, review players' medical history and imaging studies, and perform a physical examination. The purpose of this study was to test the effect of specific diagnoses and surgical procedures on the likelihood of playing and length of career in the league by position. Cohort study; Level of evidence, 3. A database for all players reviewed at the annual National Football League Combine by the medical staff of 1 National Football League team from 1987 to 2000 was created, including each player's orthopaedic rating, diagnoses, surgical procedures, number of games played, and number of seasons played in the National Football League. Athletes were grouped by position as follows: offensive backfield, offensive receiver, offensive line, quarterback, tight end, defensive line, defensive secondary, linebacker, and kicker. The percentage of athletes who played in the National Football League was calculated by position for each specific diagnosis and surgery. The effect of injury on the likelihood of playing in the league varied by position. Anterior cruciate ligament injury significantly lowered the likelihood of playing in the league for defensive linemen (P = .03) and linebackers (P = .04). Meniscal injury significantly reduced the probability of playing (P < .05) and length of career (P = .002) for athletes in the defensive secondary. Shoulder instability had a significant effect on playing in the league for offensive (P = .03) and defensive linemen (P = .02), and shortened the length of career for defensive linemen (P = .016). Spondylolisthesis did not significantly reduce the chance of playing in the league for any position, while a history of spondylolysis had a significant effect for running backs (P = .01). Miscellaneous injuries (eg. acromioclavicular joint, knee medial collateral ligament, carpal fractures) had isolated position-specific effects. The significant injuries and diagnoses appear congruent with the position-specific demands placed on the athletes. This information is useful to physicians and athletic trainers caring for college football athletes as well as those assessing these athletes at the National Football League Combine.
Sviklāne, Laura; Olmane, Evija; Dzērve, Zane; Kupčs, Kārlis; Pīrāgs, Valdis; Sokolovska, Jeļizaveta
2018-01-01
Little is known about the diagnostic value of hepatic steatosis index (HSI) and fatty liver index (FLI), as well as their link to metabolic syndrome in type 1 diabetes mellitus. We have screened the effectiveness of FLI and HSI in an observational pilot study of 40 patients with type 1 diabetes. FLI and HSI were calculated for 201 patients with type 1 diabetes. Forty patients with FLI/HSI values corresponding to different risk of liver steatosis were invited for liver magnetic resonance study. In-phase/opposed-phase technique of magnetic resonance was used. Accuracy of indices was assessed from the area under the receiver operating characteristic curve. Twelve (30.0%) patients had liver steatosis. For FLI, sensitivity was 90%; specificity, 74%; positive likelihood ratio, 3.46; negative likelihood ratio, 0.14; positive predictive value, 0.64; and negative predictive value, 0.93. For HSI, sensitivity was 86%; specificity, 66%; positive likelihood ratio, 1.95; negative likelihood ratio, 0.21; positive predictive value, 0.50; and negative predictive value, 0.92. Area under the receiver operating characteristic curve for FLI was 0.86 (95% confidence interval [0.72; 0.99]); for HSI 0.75 [0.58; 0.91]. Liver fat correlated with liver enzymes, waist circumference, triglycerides, and C-reactive protein. FLI correlated with C-reactive protein, liver enzymes, and blood pressure. HSI correlated with waist circumference and C-reactive protein. FLI ≥ 60 and HSI ≥ 36 were significantly associated with metabolic syndrome and nephropathy. The tested indices, especially FLI, can serve as surrogate markers for liver fat content and metabolic syndrome in type 1 diabetes. © 2017 Journal of Gastroenterology and Hepatology Foundation and John Wiley & Sons Australia, Ltd.
Likelihood ratios for glaucoma diagnosis using spectral-domain optical coherence tomography.
Lisboa, Renato; Mansouri, Kaweh; Zangwill, Linda M; Weinreb, Robert N; Medeiros, Felipe A
2013-11-01
To present a methodology for calculating likelihood ratios for glaucoma diagnosis for continuous retinal nerve fiber layer (RNFL) thickness measurements from spectral-domain optical coherence tomography (spectral-domain OCT). Observational cohort study. A total of 262 eyes of 187 patients with glaucoma and 190 eyes of 100 control subjects were included in the study. Subjects were recruited from the Diagnostic Innovations Glaucoma Study. Eyes with preperimetric and perimetric glaucomatous damage were included in the glaucoma group. The control group was composed of healthy eyes with normal visual fields from subjects recruited from the general population. All eyes underwent RNFL imaging with Spectralis spectral-domain OCT. Likelihood ratios for glaucoma diagnosis were estimated for specific global RNFL thickness measurements using a methodology based on estimating the tangents to the receiver operating characteristic (ROC) curve. Likelihood ratios could be determined for continuous values of average RNFL thickness. Average RNFL thickness values lower than 86 μm were associated with positive likelihood ratios (ie, likelihood ratios greater than 1), whereas RNFL thickness values higher than 86 μm were associated with negative likelihood ratios (ie, likelihood ratios smaller than 1). A modified Fagan nomogram was provided to assist calculation of posttest probability of disease from the calculated likelihood ratios and pretest probability of disease. The methodology allowed calculation of likelihood ratios for specific RNFL thickness values. By avoiding arbitrary categorization of test results, it potentially allows for an improved integration of test results into diagnostic clinical decision making. Copyright © 2013. Published by Elsevier Inc.
Weitzel, T; Schnabel, E; Dieckmann, S; Börner, U; Schweiger, B
2007-07-01
Point-of-care (POC) tests for influenza facilitate clinical case management, and might also be helpful in the care of travellers who are at special risk for influenza infection. To evaluate influenza POC testing in travellers, a new assay, the ImmunoCard STAT! Flu A and B, was used to investigate travellers presenting with influenza-like symptoms. Influenza virus infection was diagnosed in 27 (13%) of 203 patients by influenza virus-specific PCR and viral culture. The POC test had sensitivity and specificity values of 64% and 99% for influenza A, and 67% and 100% for influenza B, respectively. Combined sensitivity and specificity were 67% and 99%, respectively, yielding positive and negative predictive values of 95%, and positive and negative likelihood ratios of 117 and 0.34, respectively. The convenient application, excellent specificity and high positive likelihood ratio of the POC test allowed rapid identification of influenza cases. However, negative test results might require confirmation by other methods because of limitations in sensitivity. Overall, influenza POC testing appeared to be a useful tool for the management of travellers with influenza-like symptoms.
Who drinks where: youth selection of drinking contexts.
Lipperman-Kreda, Sharon; Mair, Christina F; Bersamin, Melina; Gruenewald, Paul J; Grube, Joel W
2015-04-01
Different drinkers may experience specific risks depending on where they consume alcohol. This longitudinal study examined drinking patterns, and demographic and psychosocial characteristics associated with youth drinking in different contexts. We used survey data from 665 past-year alcohol-using youths (ages 13 to 16 at Wave 1) in 50 midsized California cities. Measures of drinking behaviors and drinking in 7 contexts were obtained at 3 annual time points. Other characteristics included gender, age, race, parental education, weekly disposable income, general deviance, and past-year cigarette smoking. Results of multilevel regression analyses show that more frequent past-year alcohol use was associated with an increased likelihood of drinking at parties and at someone else's home. Greater continued volumes of alcohol (i.e., heavier drinking) was associated with increased likelihood of drinking at parking lots or street corners. Deviance was positively associated with drinking in most contexts, and past-year cigarette smoking was positively associated with drinking at beaches or parks and someone else's home. Age and deviance were positively associated with drinking in a greater number of contexts. The likelihood of youth drinking at parties and someone else's home increased over time, whereas the likelihood of drinking at parking lots/street corners decreased. Also, deviant youths progress to drinking in their own home, beaches or parks, and restaurants/bars/nightclubs more rapidly. The contexts in which youths consume alcohol change over time. These changes vary by individual characteristics. The redistribution of drinking contexts over the early life course may contribute to specific risks associated with different drinking contexts. Copyright © 2015 by the Research Society on Alcoholism.
Clinical Evaluation and Physical Exam Findings in Patients with Anterior Shoulder Instability.
Lizzio, Vincent A; Meta, Fabien; Fidai, Mohsin; Makhni, Eric C
2017-12-01
The goal of this paper is to provide an overview in evaluating the patient with suspected or known anteroinferior glenohumeral instability. There is a high rate of recurrent subluxations or dislocations in young patients with history of anterior shoulder dislocation, and recurrent instability will increase likelihood of further damage to the glenohumeral joint. Proper identification and treatment of anterior shoulder instability can dramatically reduce the rate of recurrent dislocation and prevent subsequent complications. Overall, the anterior release or surprise test demonstrates the best sensitivity and specificity for clinically diagnosing anterior shoulder instability, although other tests also have favorable sensitivities, specificities, positive likelihood ratios, negative likelihood ratios, and inter-rater reliabilities. Anterior shoulder instability is a relatively common injury in the young and athletic population. The combination of history and performing apprehension, relocation, release or surprise, anterior load, and anterior drawer exam maneuvers will optimize sensitivity and specificity for accurately diagnosing anterior shoulder instability in clinical practice.
Comparison between presepsin and procalcitonin in early diagnosis of neonatal sepsis.
Iskandar, Agustin; Arthamin, Maimun Z; Indriana, Kristin; Anshory, Muhammad; Hur, Mina; Di Somma, Salvatore
2018-05-09
Neonatal sepsis remains worldwide one of the leading causes of morbidity and mortality in both term and preterm infants. Lower mortality rates are related to timely diagnostic evaluation and prompt initiation of empiric antibiotic therapy. Blood culture, as gold standard examination for sepsis, has several limitations for early diagnosis, so that sepsis biomarkers could play an important role in this regard. This study was aimed to compare the value of the two biomarkers presepsin and procalcitonin in early diagnosis of neonatal sepsis. This was a prospective cross-sectional study performed, in Saiful Anwar General Hospital Malang, Indonesia, in 51 neonates that fulfill the criteria of systemic inflammatory response syndrome (SIRS) with blood culture as diagnostic gold standard for sepsis. At reviewer operating characteristic (ROC) curve analyses, using a presepsin cutoff of 706,5 pg/mL, the obtained area under the curve (AUCs) were: sensitivity = 85.7%, specificity = 68.8%, positive predictive value = 85.7%, negative predictive value = 68.8%, positive likelihood ratio = 2.75, negative likelihood ratio = 0.21, and accuracy = 80.4%. On the other hand, with a procalcitonin cutoff value of 161.33 pg/mL the obtained AUCs showed: sensitivity = 68.6%, specificity = 62.5%, positive predictive value = 80%, negative predictive value = 47.6%, positive likelihood ratio = 1.83, the odds ratio negative = 0.5, and accuracy = 66.7%. In early diagnosis of neonatal sepsis, compared with procalcitonin, presepsin seems to provide better early diagnostic value with consequent possible faster therapeutical decision making and possible positive impact on outcome of neonates.
Xu, Mei-Mei; Jia, Hong-Yu; Yan, Li-Li; Li, Shan-Shan; Zheng, Yue
2017-01-01
Abstract Background: This meta-analysis aimed to provide a pooled analysis of prospective controlled trials comparing the diagnostic accuracy of 22-G and 25-G needles on endoscopic ultrasonography (EUS-FNA) of the solid pancreatic mass. Methods: We established a rigorous study protocol according to Cochrane Collaboration recommendations. We systematically searched the PubMed and Embase databases to identify articles to include in the meta-analysis. Sensitivity, specificity, and corresponding 95% confidence intervals were calculated for 22-G and 25-G needles of individual studies from the contingency tables. Results: Eleven prospective controlled trials included a total of 837 patients (412 with 22-G vs 425 with 25-G). Our outcomes revealed that 25-G needles (92% [95% CI, 89%–95%]) have higher sensitivity than 22-G needles (88% [95% CI, 84%–91%]) on solid pancreatic mass EUS-FNA (P = 0.046). However, there were no significant differences between the 2 groups in overall diagnostic specificity (P = 0.842). The pooled positive and negative likelihood ratio of the 22-G needle were 12.61 (95% CI, 5.65–28.14) and 0.16 (95% CI, 0.12–0.21), respectively. The pooled positive likelihood ratio was 12.61 (95% CI, 5.65–28.14), and the negative likelihood ratio was 0.16 (95% CI, 0.12–0.21) for the 22-G needle. The pooled positive likelihood ratio was 8.44 (95% CI, 3.87–18.42), and the negative likelihood ratio was 0.13 (95% CI, 0.09–0.18) for the 25-G needle. The area under the summary receiver operating characteristic curve was 0.97 for the 22-G needle and 0.96 for the 25-G needle. Conclusion: Compared to the study of 22-G EUS-FNA needles, our study showed that 25-G needles have superior sensitivity in the evaluation of solid pancreatic lesions by EUS–FNA. PMID:28151856
Weemhoff, M; Kluivers, K B; Govaert, B; Evers, J L H; Kessels, A G H; Baeten, C G
2013-03-01
This study concerns the level of agreement between transperineal ultrasound and evacuation proctography for diagnosing enteroceles and intussusceptions. In a prospective observational study, 50 consecutive women who were planned to have an evacuation proctography underwent transperineal ultrasound too. Sensitivity, specificity, positive (PPV) and negative predictive value, as well as the positive and negative likelihood ratio of transperineal ultrasound were assessed in comparison to evacuation proctography. To determine the interobserver agreement of transperineal ultrasound, the quadratic weighted kappa was calculated. Furthermore, receiver operating characteristic curves were generated to show the diagnostic capability of transperineal ultrasound. For diagnosing intussusceptions (PPV 1.00), a positive finding on transperineal ultrasound was predictive of an abnormal evacuation proctography. Sensitivity of transperineal ultrasound was poor for intussusceptions (0.25). For diagnosing enteroceles, the positive likelihood ratio was 2.10 and the negative likelihood ratio, 0.85. There are many false-positive findings of enteroceles on ultrasonography (PPV 0.29). The interobserver agreement of the two ultrasonographers assessed as the quadratic weighted kappa of diagnosing enteroceles was 0.44 and that of diagnosing intussusceptions was 0.23. An intussusception on ultrasound is predictive of an abnormal evacuation proctography. For diagnosing enteroceles, the diagnostic quality of transperineal ultrasound was limited compared to evacuation proctography.
Pan, Liping; Jia, Hongyan; Liu, Fei; Gao, Mengqiu; Sun, Huishan; Du, Boping; Sun, Qi; Xing, Aiying; Wei, Rongrong; Zhang, Zongde
2015-12-01
To evaluate the value of T-SPOT.TB assay in the diagnosis of pulmonary tuberculosis within different age groups. We analyzed 1 518 suspected pulmonary tuberculosis (PTB) patients who were admitted to the Beijing Chest Hospital from November 2012 to February 2014 and had valid T-SPOT.TB tests before anti-tuberculosis therapy. The 599 microbiologically and/or histopathologically-confirmed PTB patients (16-89 years old, 388 males and 211 females) and 235 non-TB patients (14-85 years old, 144 males and 91 females) were enrolled for the analysis of diagnostic performance of T-SPOT.TB, while patients with uncertain diagnosis or diagnosis based on clinical impression (n=684) were excluded from the analysis. The sensitivity, specificity, positive predictive value, negative predictive value, positive likelihood ratio, and negative likelihood ratio of the T-SPOT.TB were analyzed according to the final diagnosis. Furthermore, the diagnostic performance of T-SPOT.TB assay in the younger patients (14-59 years old) and elderly patients (60-89 years old) were also analyzed respectively. Categorical variables were compared by Pearson's Chi-square test, while continuous variables were compared by the Mann-Whitney U-test. The sensitivity, specificity, positive predictive value, negative predictive value, positive likelihood ratio, and negative likelihood ratio of the T-SPOT.TB in diagnosis of PTB were 90.1% (540/599), 65.5% (154/235), 86.9% (540/621), 72.3% (154/213), 2.61, and 0.15, respectively. The sensitivity and specificity of T-SPOT.TB assay were 92.6% (375/405) and 75.6% (99/131), respectively in the younger patients, and 85.0% (165/194), 52.9% (55/104) respectively in the elderly patients. The sensitivity and specificity of T-SPOT.TB assay in the younger patients were significantly higher than those in the elderly patients (P<0.01), and the spot forming cells in the younger PTB patients were significantly higher than in the elderly PTB patients [300 (126, 666)/10(6) PBMCs vs. 258 (79, 621)/10(6) PBMCs, P=0.037]. T-SPOT.TB is a promising test in the diagnosis of younger patients (14-59 years old) with suspected PTB, but the diagnostic performance in elderly patients (60-89 years old) is relatively reduced.
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
Wan, Bing; Wang, Siqi; Tu, Mengqi; Wu, Bo; Han, Ping; Xu, Haibo
2017-03-01
The purpose of this meta-analysis was to evaluate the diagnostic accuracy of perfusion magnetic resonance imaging (MRI) as a method for differentiating glioma recurrence from pseudoprogression. The PubMed, Embase, Cochrane Library, and Chinese Biomedical databases were searched comprehensively for relevant studies up to August 3, 2016 according to specific inclusion and exclusion criteria. The quality of the included studies was assessed according to the quality assessment of diagnostic accuracy studies (QUADAS-2). After performing heterogeneity and threshold effect tests, pooled sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, and diagnostic odds ratio were calculated. Publication bias was evaluated visually by a funnel plot and quantitatively using Deek funnel plot asymmetry test. The area under the summary receiver operating characteristic curve was calculated to demonstrate the diagnostic performance of perfusion MRI. Eleven studies covering 416 patients and 418 lesions were included in this meta-analysis. The pooled sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, and diagnostic odds ratio were 0.88 (95% confidence interval [CI] 0.84-0.92), 0.77 (95% CI 0.69-0.84), 3.93 (95% CI 2.83-5.46), 0.16 (95% CI 0.11-0.22), and 27.17 (95% CI 14.96-49.35), respectively. The area under the summary receiver operating characteristic curve was 0.8899. There was no notable publication bias. Sensitivity analysis showed that the meta-analysis results were stable and credible. While perfusion MRI is not the ideal diagnostic method for differentiating glioma recurrence from pseudoprogression, it could improve diagnostic accuracy. Therefore, further research on combining perfusion MRI with other imaging modalities is warranted.
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.
Aragón-Sánchez, J; Lipsky, Benjamin A; Lázaro-Martínez, J L
2011-02-01
To investigate the accuracy of the sequential combination of the probe-to-bone test and plain X-rays for diagnosing osteomyelitis in the foot of patients with diabetes. We prospectively compiled data on a series of 338 patients with diabetes with 356 episodes of foot infection who were hospitalized in the Diabetic Foot Unit of La Paloma Hospital from 1 October 2002 to 31 April 2010. For each patient we did a probe-to-bone test at the time of the initial evaluation and then obtained plain X-rays of the involved foot. All patients with positive results on either the probe-to-bone test or plain X-ray underwent an appropriate surgical procedure, which included obtaining a bone specimen that was processed for histology and culture. We calculated the sensitivity, specificity, predictive values and likelihood ratios of the procedures, using the histopathological diagnosis of osteomyelitis as the criterion standard. Overall, 72.4% of patients had histologically proven osteomyelitis, 85.2% of whom had positive bone culture. The performance characteristics of both the probe-to-bone test and plain X-rays were excellent. The sequential diagnostic approach had a sensitivity of 0.97, specificity of 0.92, positive predictive value of 0.97, negative predictive value of 0.93, positive likelihood ratio of 12.8 and negative likelihood ratio of 0.02. Only 6.6% of patients with negative results on both diagnostic studies had osteomyelitis. Clinicians seeing patients in a setting similar to ours (specialized diabetic foot unit with a high prevalence of osteomyelitis) can confidently diagnose diabetic foot osteomyelitis when either the probe-to-bone test or a plain X-ray, or especially both, are positive. © 2011 The Authors. Diabetic Medicine © 2011 Diabetes UK.
Accuracy of diagnostic tests to detect asymptomatic bacteriuria during pregnancy.
Mignini, Luciano; Carroli, Guillermo; Abalos, Edgardo; Widmer, Mariana; Amigot, Susana; Nardin, Juan Manuel; Giordano, Daniel; Merialdi, Mario; Arciero, Graciela; Del Carmen Hourquescos, Maria
2009-02-01
A dipslide is a plastic paddle coated with agar that is attached to a plastic cap that screws onto a sterile plastic vial. Our objective was to estimate the diagnostic accuracy of the dipslide culture technique to detect asymptomatic bacteriuria during pregnancy and to evaluate the accuracy of nitrate and leucocyte esterase dipslides for screening. This was an ancillary study within a trial comparing single-day with 7-day therapy in treating asymptomatic bacteriuria. Clean-catch midstream samples were collected from pregnant women seeking routine care. Positive and negative likelihood ratios and sensitivity and specificity for the culture-based dipslide to detect and chemical dipsticks (nitrites, leukocyte esterase, or both) to screen were estimated using traditional urine culture as the "gold standard." : A total of 3,048 eligible pregnant women were screened. The prevalence of asymptomatic bacteriuria was 15%, with Escherichia coli the most prevalent organism. The likelihood ratio for detecting asymptomatic bacteriuria with a positive dipslide test was 225 (95% confidence interval [CI] 113-449), increasing the probability of asymptomatic bacteriuria to 98%; the likelihood ratio for a negative dipslide test was 0.02 (95% CI 0.01-0.05), reducing the probability of bacteriuria to less than 1%. The positive likelihood ratio of leukocyte esterase and nitrite dipsticks (when both or either one was positive) was 6.95 (95% CI 5.80-8.33), increasing the probability of bacteriuria to only 54%; the negative likelihood ratio was 0.50 (95% CI 0.45-0.57), reducing the probability to 8%. A pregnant woman with a positive dipslide test is very likely to have a definitive diagnosis of asymptomatic bacteriuria, whereas a negative result effectively rules out the presence of bacteriuria. Dipsticks that measure nitrites and leukocyte esterase have low sensitivity for use in screening for asymptomatic bacteriuria during gestation. ISRCTN, isrctn.org, 1196608 II.
[Clinical examination and the Valsalva maneuver in heart failure].
Liniado, Guillermo E; Beck, Martín A; Gimeno, Graciela M; González, Ana L; Cianciulli, Tomás F; Castiello, Gustavo G; Gagliardi, Juan A
2018-01-01
Congestion in heart failure patients with reduced ejection fraction (HFrEF) is relevant and closely linked to the clinical course. Bedside blood pressure measurement during the Valsalva maneuver (Val) added to clinical examination may improve the assessment of congestion when compared to NT-proBNP levels and left atrial pressure (LAP) estimation by Doppler echocardiography, as surrogate markers of congestion in HFrEF. A clinical examination, LAP and blood tests were performed in 69 HFrEF ambulatory patients with left ventricular ejection fraction ≤ 40% and sinus rhythm. Framingham Heart Failure Score (HFS) was used to evaluate clinical congestion; Val was classified as normal or abnormal, NT-proBNP was classified as low (< 1000 pg/ml) or high (≥ 1000 pg/ml) and the ratio between Doppler early mitral inflow and tissue diastolic velocity was used to estimate LAP and was classified as low (E/e'< 15) or high (E/e' ≥ 15). A total of 69 patients with HFrEF were included; 27 had a HFS ≥ 2 and 13 of them had high NT-proBNP. HFS ≥ 2 had a 62% sensitivity, 70% specificity and a positive likelihood ratio of 2.08 (p=0.01) to detect congestion. When Val was added to clinical examination, the presence of a HFS ≥ 2 and abnormal Val showed a 100% sensitivity, 64% specificity and a positive likelihood ratio of 2.8 (p = 0.0004). Compared with LAP, the presence of HFS = 2 and abnormal Val had 86% sensitivity, 54% specificity and a positive likelihood ratio of 1.86 (p = 0.03). In conclusion, an integrated clinical examination with the addition Valsalva maneuver may improve the assessment of congestion in patients with HFrEF.
Likelihood Ratios for Glaucoma Diagnosis Using Spectral Domain Optical Coherence Tomography
Lisboa, Renato; Mansouri, Kaweh; Zangwill, Linda M.; Weinreb, Robert N.; Medeiros, Felipe A.
2014-01-01
Purpose To present a methodology for calculating likelihood ratios for glaucoma diagnosis for continuous retinal nerve fiber layer (RNFL) thickness measurements from spectral domain optical coherence tomography (spectral-domain OCT). Design Observational cohort study. Methods 262 eyes of 187 patients with glaucoma and 190 eyes of 100 control subjects were included in the study. Subjects were recruited from the Diagnostic Innovations Glaucoma Study. Eyes with preperimetric and perimetric glaucomatous damage were included in the glaucoma group. The control group was composed of healthy eyes with normal visual fields from subjects recruited from the general population. All eyes underwent RNFL imaging with Spectralis spectral-domain OCT. Likelihood ratios for glaucoma diagnosis were estimated for specific global RNFL thickness measurements using a methodology based on estimating the tangents to the Receiver Operating Characteristic (ROC) curve. Results Likelihood ratios could be determined for continuous values of average RNFL thickness. Average RNFL thickness values lower than 86μm were associated with positive LRs, i.e., LRs greater than 1; whereas RNFL thickness values higher than 86μm were associated with negative LRs, i.e., LRs smaller than 1. A modified Fagan nomogram was provided to assist calculation of post-test probability of disease from the calculated likelihood ratios and pretest probability of disease. Conclusion The methodology allowed calculation of likelihood ratios for specific RNFL thickness values. By avoiding arbitrary categorization of test results, it potentially allows for an improved integration of test results into diagnostic clinical decision-making. PMID:23972303
Álvarez-Díaz, N; Amador-García, I; Fuentes-Hernández, M; Dorta-Guerra, R
2015-01-01
To compare the ability of lung ultrasound and a clinical method in the confirmation of a selective bronchial intubation by left double-lumen tube in elective thoracic surgery. A prospective and blind, observational study was conducted in the setting of a university hospital operating room assigned for thoracic surgery. A single group of 105 consecutive patients from a total of 130, were included. After blind intubation, the position of the tube was confirmed by clinical and ultrasound assessment. Finally, the fiberoptic bronchoscopy confirmation as a reference standard was used to confirm the position of the tube. Under manual ventilation, by sequentially clamping the tracheal and bronchial limbs of the tube, clinical confirmation was made by auscultation, capnography, visualizing the chest wall expansion, and perceiving the lung compliance in the reservoir bag. Ultrasound confirmation was obtained by visualizing lung sliding, diaphragmatic movements, and the appearance of lung pulse sign. The sensitivity of the clinical method was 84.5%, with a specificity of 41.1%. The positive and negative likelihood ratio was 1.44 and 0.38, respectively. The sensitivity of the ultrasound method was 98.6%, specificity was 52.9%, with a positive likelihood ratio of 2.10 and a negative likelihood ratio of 0.03. Comparisons between the diagnostic performance of the 2 methods were calculated with McNemar's test. There was a significant difference in sensitivity between the ultrasound method and the clinical method (P=.002). Nevertheless, there was no statistically significant difference in specificity between both methods (P=.34). A p value<.01 was considered statistically significant. Lung ultrasound was superior to the clinical method in confirming the adequate position of the left double-lumen tube. On the other hand, in confirming the misplacement of the tube, differences between both methods could not be ensured. Copyright © 2014 Sociedad Española de Anestesiología, Reanimación y Terapéutica del Dolor. Publicado por Elsevier España, S.L.U. All rights reserved.
[Accuracy of three methods for the rapid diagnosis of oral candidiasis].
Lyu, X; Zhao, C; Yan, Z M; Hua, H
2016-10-09
Objective: To explore a simple, rapid and efficient method for the diagnosis of oral candidiasis in clinical practice. Methods: Totally 124 consecutive patients with suspected oral candidiasis were enrolled from Department of Oral Medicine, Peking University School and Hospital of Stomatology, Beijing, China. Exfoliated cells of oral mucosa and saliva or concentrated oral rinse) obtained from all participants were tested by three rapid smear methods(10% KOH smear, gram-stained smear, Congo red stained smear). The diagnostic efficacy(sensitivity, specificity, Youden's index, likelihood ratio, consistency, predictive value and area under curve(AUC) of each of the above mentioned three methods was assessed by comparing the results with the gold standard(combination of clinical diagnosis, laboratory diagnosis and expert opinion). Results: Gram-stained smear of saliva(or concentrated oral rinse) demonstrated highest sensitivity(82.3%). Test of 10%KOH smear of exfoliated cells showed highest specificity(93.5%). Congo red stained smear of saliva(or concentrated oral rinse) displayed highest diagnostic efficacy(79.0% sensitivity, 80.6% specificity, 0.60 Youden's index, 4.08 positive likelihood ratio, 0.26 negative likelihood ratio, 80% consistency, 80.3% positive predictive value, 79.4% negative predictive value and 0.80 AUC). Conclusions: Test of Congo red stained smear of saliva(or concentrated oral rinse) could be used as a point-of-care tool for the rapid diagnosis of oral candidiasis in clinical practice. Trial registration: Chinese Clinical Trial Registry, ChiCTR-DDD-16008118.
Ismael, Alaa Bassuny; Swelum, Ayman Abdel-Aziz; Mostafa, Salama A-H; Alhumiany, Abdel-Rahman A
2016-01-01
Brucellosis, especially caused by Brucella melitensis, is considered the most-widespread zoonosis in the world, particularly in developing countries. This study was planned to develop an accurate test for diagnosis of ovine brucellosis using a specific hot saline extracted soluble Brucella melitensis periplasmic proteins (SBPPs). The efficacy of the latex agglutination test (LAT) using SBPPs compared to the Rose Bengal test (RBT), buffered plate agglutination test (BPAT), serum agglutination test (SAT), and an indirect enzyme-linked immunosorbent assay (i-ELISA) was evaluated in the field diagnosis of ovine brucellosis. The test performance was evaluated by estimating sensitivity (Se), specificity (Sp), positive predictive value (PPV), negative predictive value (NPV), disease prevalence (DP), positive likelihood ratio (PLR), and negative likelihood ratio (NLR) using test agreement and bacteriological culture in 1777 samples. The false-positive result was significantly (P ⩽0.05) lower in LAT than RBT, BPAT, SAT, and i-ELISA. With reference to test agreement, the Se, Sp, PPV, and PLR were highest (P ⩽0.05) in LAT 99.33%, 99.88%, 98.68%, and 827.25%, respectively. With reference to bacteriological culture, the LAT and i-ELISA tests showed a significant difference in Se with SAT. However, no significant difference in specificity was detected. The DP was 8.44% in the five tests. In conclusion, LAT using SBPPs of B. melitensis could be a suitable serodiagnostic field test for ovine brucellosis, with high sensitivity and specificity. PMID:27207442
Ismael, Alaa Bassuny; Swelum, Ayman Abdel-Aziz; Mostafa, Salama A-H; Alhumiany, Abdel-Rahman A
2016-09-01
Brucellosis, especially caused by Brucella melitensis, is considered the most-widespread zoonosis in the world, particularly in developing countries. This study was planned to develop an accurate test for diagnosis of ovine brucellosis using a specific hot saline extracted soluble Brucella melitensis periplasmic proteins (SBPPs). The efficacy of the latex agglutination test (LAT) using SBPPs compared to the Rose Bengal test (RBT), buffered plate agglutination test (BPAT), serum agglutination test (SAT), and an indirect enzyme-linked immunosorbent assay (i-ELISA) was evaluated in the field diagnosis of ovine brucellosis. The test performance was evaluated by estimating sensitivity (Se), specificity (Sp), positive predictive value (PPV), negative predictive value (NPV), disease prevalence (DP), positive likelihood ratio (PLR), and negative likelihood ratio (NLR) using test agreement and bacteriological culture in 1777 samples. The false-positive result was significantly (P ⩽0.05) lower in LAT than RBT, BPAT, SAT, and i-ELISA. With reference to test agreement, the Se, Sp, PPV, and PLR were highest (P ⩽0.05) in LAT 99.33%, 99.88%, 98.68%, and 827.25%, respectively. With reference to bacteriological culture, the LAT and i-ELISA tests showed a significant difference in Se with SAT. However, no significant difference in specificity was detected. The DP was 8.44% in the five tests. In conclusion, LAT using SBPPs of B. melitensis could be a suitable serodiagnostic field test for ovine brucellosis, with high sensitivity and specificity. © The Author(s) 2016.
Silverman, Merav H.; Jedd, Kelly; Luciana, Monica
2015-01-01
Behavioral responses to, and the neural processing of, rewards change dramatically during adolescence and may contribute to observed increases in risk-taking during this developmental period. Functional MRI (fMRI) studies suggest differences between adolescents and adults in neural activation during reward processing, but findings are contradictory, and effects have been found in non-predicted directions. The current study uses an activation likelihood estimation (ALE) approach for quantitative meta-analysis of functional neuroimaging studies to: 1) confirm the network of brain regions involved in adolescents’ reward processing, 2) identify regions involved in specific stages (anticipation, outcome) and valence (positive, negative) of reward processing, and 3) identify differences in activation likelihood between adolescent and adult reward-related brain activation. Results reveal a subcortical network of brain regions involved in adolescent reward processing similar to that found in adults with major hubs including the ventral and dorsal striatum, insula, and posterior cingulate cortex (PCC). Contrast analyses find that adolescents exhibit greater likelihood of activation in the insula while processing anticipation relative to outcome and greater likelihood of activation in the putamen and amygdala during outcome relative to anticipation. While processing positive compared to negative valence, adolescents show increased likelihood for activation in the posterior cingulate cortex (PCC) and ventral striatum. Contrasting adolescent reward processing with the existing ALE of adult reward processing (Liu et al., 2011) reveals increased likelihood for activation in limbic, frontolimbic, and striatal regions in adolescents compared with adults. Unlike adolescents, adults also activate executive control regions of the frontal and parietal lobes. These findings support hypothesized elevations in motivated activity during adolescence. PMID:26254587
NASA Astrophysics Data System (ADS)
Rahardjo, K. D.; Dharmaeizar; Nainggolan, G.; Harimurti, K.
2017-08-01
Research has shown that hemodialysis patients with lung congestion have high morbidity and mortality. Patients were assumed to be free of lung congestion if they had reached their post-dialysis dry weight. Most often, to determine if the patient was free of lung congestion, physical examination was used. However, the accuracy of physical examination in detecting lung congestion has not been established. To compare the capabilities of physical examination and lung ultrasound in detection of lung congestion, cross-sectional data collection was conducted on hemodialysis patients. Analysis was done to obtain proportion, sensitivity, specificity, positive predictive value, negative predictive value, and positive likelihood ratio. Sixty patients participated in this study. The inter observer variation of 20 patients revealed a kappa value of 0.828. When all 60 patients were taken into account, we found that 36 patients (57.1%) had lung congestion. Mild lung congestion was found in 24 (38.1%), and 12 (19%) had a moderate degree of congestion. In the analysis comparing jugular venous pressure to lung ultrasound, we found that sensitivity was 0.47 (0.31-0.63), specificity was 0.73 (0.54-0.86), positive predictive value (PPV) was 0.51 (0.36-0.67), negative predictive value (NPV) was 0.70 (0.49-0.84), positive likelihood ratio (PLR) was 1.75 (0.88-3.47), and the negative likelihood ratio (NLR) was 0.72 (0.47-1.12). In terms of lung auscultation, we found that sensitivity was 0.56 (0.39-0.71), specificity was 0.54 (0.35-0.71), PPV was 0.61 (0.44-0.76), NPV was 0.48 (0.31-0.66), PLR was 1.21 (0.73-2.0), and NLR was 0.82 (0.49-1.38). The results of our study showed that jugular venous distention and lung auscultation examination are not reliable means of detecting lung congestion.
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.
Dvorak, Robert D; Simons, Jeffrey S
2014-12-01
Many theories of emotion regulation and alcohol use posit that alcohol is consumed as a way to regulate negative mood. However, the literature has conflicting evidence on mood-alcohol use associations. Understanding how individual differences affect mood-alcohol use associations remains an important area of study. Previous research has suggested that cognitive abilities may affect the relationship between mood and alcohol. The current ecological momentary study examined associations between daytime anxious and positive mood and both (a) the likelihood of alcohol use and (b) the intensity of use on drinking nights as a function of sustained attention, set shifting, and gender. Participants (n = 100) completed assessments of sustained attention and set shifting, then carried palmtop computers for 21 days, reporting mood and alcohol use up to 8 times per day. Results showed that positive mood was consistently associated with both likelihood and intensity of alcohol use, but the association between positive mood and alcohol outcomes was not affected by cognitive abilities. Anxious mood was positively associated with the likelihood of drinking for men with high cognitive abilities. Anxious mood was positively associated with intoxication on drinking nights for men with high sustained attention, but inversely associated with intoxication on drinking nights for women with high sustained attention. Results suggest that variation in mood, executive functioning, and gender interact to contribute to observed differences in drinking behavior. These differences may be the result of gender-specific coping strategies in response to negative emotion.
Church, Sheri A; Livingstone, Kevin; Lai, Zhao; Kozik, Alexander; Knapp, Steven J; Michelmore, Richard W; Rieseberg, Loren H
2007-02-01
Using likelihood-based variable selection models, we determined if positive selection was acting on 523 EST sequence pairs from two lineages of sunflower and lettuce. Variable rate models are generally not used for comparisons of sequence pairs due to the limited information and the inaccuracy of estimates of specific substitution rates. However, previous studies have shown that the likelihood ratio test (LRT) is reliable for detecting positive selection, even with low numbers of sequences. These analyses identified 56 genes that show a signature of selection, of which 75% were not identified by simpler models that average selection across codons. Subsequent mapping studies in sunflower show four of five of the positively selected genes identified by these methods mapped to domestication QTLs. We discuss the validity and limitations of using variable rate models for comparisons of sequence pairs, as well as the limitations of using ESTs for identification of positively selected genes.
Likelihood-Based Clustering of Meta-Analytic SROC Curves
ERIC Educational Resources Information Center
Holling, Heinz; Bohning, Walailuck; Bohning, Dankmar
2012-01-01
Meta-analysis of diagnostic studies experience the common problem that different studies might not be comparable since they have been using a different cut-off value for the continuous or ordered categorical diagnostic test value defining different regions for which the diagnostic test is defined to be positive. Hence specificities and…
Liu, Bo-Ji; Li, Dan-Dan; Xu, Hui-Xiong; Guo, Le-Hang; Zhang, Yi-Feng; Xu, Jun-Mei; Liu, Chang; Liu, Lin-Na; Li, Xiao-Long; Xu, Xiao-Hong; Qu, Shen; Xing, Mingzhao
2015-12-01
The aim of this study was to evaluate the diagnostic performance of quantitative shear wave velocity (SWV) measurement on acoustic radiation force impulse (ARFI) elastography for differentiation between benign and malignant thyroid nodules using meta-analysis. The databases of PubMed and the Web of Science were searched. Studies published in English on assessment of the sensitivity and specificity of ARFI elastography for the differentiation of thyroid nodules were collected. The quantitative measurement of ARFI elastography was evaluated by SWV (m/s). Meta-Disc Version 1.4 software was used to describe and calculate the sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, diagnostic odds ratio and summary receiver operating characteristic curves. We analyzed a total of 13 studies, which included 1,854 thyroid nodules (including 1,339 benign nodules and 515 malignant nodules) from 1,641 patients. The summary sensitivity and specificity for differential diagnosis between benign and malignant thyroid nodules by SWV were 0.81 (95% confidence interval [CI]: 0.77-0.84) and 0.84 (95% CI: 0.81-0.86), respectively. The pooled positive and negative likelihood ratios were 5.21 (95% CI: 3.56-7.62) and 0.23 (95% CI: 0.17-0.32), respectively. The pooled diagnostic odds ratio was 27.53 (95% CI: 14.58-52.01), and the area under the summary receiver operating characteristic curve was 0.91 (Q* = 0.84). In conclusion, SWV measurement on ARFI elastography has high sensitivity and specificity for differential diagnosis between benign and malignant thyroid nodules and can be used in combination with conventional ultrasound. Copyright © 2015 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.
Diagnostic Accuracy of the Slump Test for Identifying Neuropathic Pain in the Lower Limb.
Urban, Lawrence M; MacNeil, Brian J
2015-08-01
Diagnostic accuracy study with nonconsecutive enrollment. To assess the diagnostic accuracy of the slump test for neuropathic pain (NeP) in those with low to moderate levels of chronic low back pain (LBP), and to determine whether accuracy of the slump test improves by adding anatomical or qualitative pain descriptors. Neuropathic pain has been linked with poor outcomes, likely due to inadequate diagnosis, which precludes treatment specific for NeP. Current diagnostic approaches are time consuming or lack accuracy. A convenience sample of 21 individuals with LBP, with or without radiating leg pain, was recruited. A standardized neurosensory examination was used to determine the reference diagnosis for NeP. Afterward, the slump test was administered to all participants. Reports of pain location and quality produced during the slump test were recorded. The neurosensory examination designated 11 of the 21 participants with LBP/sciatica as having NeP. The slump test displayed high sensitivity (0.91), moderate specificity (0.70), a positive likelihood ratio of 3.03, and a negative likelihood ratio of 0.13. Adding the criterion of pain below the knee significantly increased specificity to 1.00 (positive likelihood ratio = 11.9). Pain-quality descriptors did not improve diagnostic accuracy. The slump test was highly sensitive in identifying NeP within the study sample. Adding a pain-location criterion improved specificity. Combining the diagnostic outcomes was very effective in identifying all those without NeP and half of those with NeP. Limitations arising from the small and narrow spectrum of participants with LBP/sciatica sampled within the study prevent application of the findings to a wider population. Diagnosis, level 4-.
Subjective global assessment of nutritional status in children.
Mahdavi, Aida Malek; Ostadrahimi, Alireza; Safaiyan, Abdolrasool
2010-10-01
This study was aimed to compare the subjective and objective nutritional assessments and to analyse the performance of subjective global assessment (SGA) of nutritional status in diagnosing undernutrition in paediatric patients. One hundred and forty children (aged 2-12 years) hospitalized consecutively in Tabriz Paediatric Hospital from June 2008 to August 2008 underwent subjective assessment using the SGA questionnaire and objective assessment, including anthropometric and biochemical measurements. Agreement between two assessment methods was analysed by the kappa (κ) statistic. Statistical indicators including (sensitivity, specificity, predictive values, error rates, accuracy, powers, likelihood ratios and odds ratio) between SGA and objective assessment method were determined. The overall prevalence of undernutrition according to the SGA (70.7%) was higher than that by objective assessment of nutritional status (48.5%). Agreement between the two evaluation methods was only fair to moderate (κ = 0.336, P < 0.001). The sensitivity, specificity, positive and negative predictive value of the SGA method for screening undernutrition in this population were 88.235%, 45.833%, 60.606% and 80.487%, respectively. Accuracy, positive and negative power of the SGA method were 66.428%, 56.074% and 41.25%, respectively. Likelihood ratio positive, likelihood ratio negative and odds ratio of the SGA method were 1.628, 0.256 and 6.359, respectively. Our findings indicated that in assessing nutritional status of children, there is not a good level of agreement between SGA and objective nutritional assessment. In addition, SGA is a highly sensitive tool for assessing nutritional status and could identify children at risk of developing undernutrition. © 2009 Blackwell Publishing Ltd.
Sun, Changling; Zhang, Yayun; Han, Xue; Du, Xiaodong
2018-03-01
Objective The purposes of this study were to verify the effectiveness of the narrow band imaging (NBI) system in diagnosing nasopharyngeal cancer (NPC) as compared with white light endoscopy. Data Sources PubMed, Cochrane Library, EMBASE, CNKI, and Wan Fang databases. Review Methods Data analyses were performed with Meta-Disc. The updated Quality Assessment of Diagnostic Accuracy Studies-2 tool was used to assess study quality and potential bias. Publication bias was assessed with a Deeks asymmetry test. The registry number of the protocol published on PROSPERO is CRD42015026244. Results This meta-analysis included 10 studies of 1337 lesions. For NBI diagnosis of NPC, the pooled values were as follows: sensitivity, 0.83 (95% CI, 0.80-0.86); specificity, 0.91 (95% CI, 0.89-0.93); positive likelihood ratio, 8.82 (95% CI, 5.12-15.21); negative likelihood ratio, 0.18 (95% CI, 0.12-0.27); and diagnostic odds ratio, 65.73 (95% CI, 36.74-117.60). The area under the curve was 0.9549. For white light endoscopy in diagnosing NPC, the pooled values were as follows: sensitivity, 0.79 (95% CI, 0.75-0.83); specificity, 0.87 (95% CI, 0.84-0.90); positive likelihood ratio, 5.02 (95% CI, 1.99-12.65); negative likelihood ratio, 0.34 (95% CI, 0.24-0.49); and diagnostic odds ratio, 16.89 (95% CI, 5.98-47.66). The area under the curve was 0.8627. The evaluation of heterogeneity, calculated per the diagnostic odds ratio, gave an I 2 of 0.326. No marked publication bias ( P = .68) existed in this meta-analysis. Conclusion The sensitivity and specificity of NBI for the diagnosis of NPC are similar to those of white light endoscopy, and the potential value of NBI for the diagnosis of NPC needs to be validated further.
Ruilong, Zong; Daohai, Xie; Li, Geng; Xiaohong, Wang; Chunjie, Wang; Lei, Tian
2017-01-01
To carry out a meta-analysis on the performance of fluorine-18-fluorodeoxyglucose (F-FDG) PET/computed tomography (PET/CT) for the evaluation of solitary pulmonary nodules. In the meta-analysis, we performed searches of several electronic databases for relevant studies, including Google Scholar, PubMed, Cochrane Library, and several Chinese databases. The quality of all included studies was assessed by Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2). Two observers independently extracted data of eligible articles. For the meta-analysis, the total sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, and diagnostic odds ratios were pooled. A summary receiver operating characteristic curve was constructed. The I-test was performed to assess the impact of study heterogeneity on the results of the meta-analysis. Meta-regression and subgroup analysis were carried out to investigate the potential covariates that might have considerable impacts on heterogeneity. Overall, 12 studies were included in this meta-analysis, including a total of 1297 patients and 1301 pulmonary nodules. The pooled sensitivity, specificity, positive likelihood ratio, and negative likelihood ratio with corresponding 95% confidence intervals (CIs) were 0.82 (95% CI, 0.76-0.87), 0.81 (95% CI, 0.66-0.90), 4.3 (95% CI, 2.3-7.9), and 0.22 (95% CI, 0.16-0.30), respectively. Significant heterogeneity was observed in sensitivity (I=81.1%) and specificity (I=89.6%). Subgroup analysis showed that the best results for sensitivity (0.90; 95% CI, 0.68-0.86) and accuracy (0.93; 95% CI, 0.90-0.95) were present in a prospective study. The results of our analysis suggest that PET/CT is a useful tool for detecting malignant pulmonary nodules qualitatively. Although current evidence showed moderate accuracy for PET/CT in differentiating malignant from benign solitary pulmonary nodules, further work needs to be carried out to improve its reliability.
Can We Rule Out Meningitis from Negative Jolt Accentuation? A Retrospective Cohort Study.
Sato, Ryota; Kuriyama, Akira; Luthe, Sarah Kyuragi
2017-04-01
Jolt accentuation has been considered to be the most sensitive physical finding to predict meningitis. However, there are only a few studies assessing the diagnostic accuracy of jolt accentuation. Therefore, we aimed to evaluate the diagnostic accuracy of jolt accentuation and investigate whether it can be extended to patients with mild altered mental status. We performed a single center, retrospective observational study on patients who presented to the emergency department in a Japanese tertiary care center from January 1, 2010 to March 31, 2016. Jolt accentuation evaluated in patients with fever, headache, and mild altered mental status with Glasgow Coma Scale no lower than E2 or M4 was defined as "jolt accentuation in the broad sense." Jolt accentuation evaluated in patients with fever, headache, and no altered mental status was defined as "jolt accentuation in the narrow sense." We evaluated the sensitivity and specificity in both groups. Among 118 patients, the sensitivity and specificity of jolt accentuation in the broad sense were 70.7% (95% confidence interval (CI): 58.0%-80.8%) and 36.7% (95% CI: 25.6%-49.3%). The positive likelihood ratio and negative likelihood ratio were 1.12 (95% CI: 0.87-1.44) and 0.80 (95% CI: 0.48-1.34), respectively. Among 108 patients, the sensitivity and specificity of jot accentuation in the narrow sense were 75.0% (95% CI: 61.8%-84.8%) and 35.1% (95% CI: 24.0%-48.0%). The positive likelihood ratio and negative likelihood ratio were 1.16 (95% CI: 0.90-1.48) and 0.71 (95% CI: 0.40-1.28), respectively. Jolt accentuation itself has a limited value in the diagnosis of meningitis regardless of altered mental status. Therefore, meningitis should not be ruled out by negative jolt accentuation. © 2017 American Headache Society.
Diagnostic Performance of Electronic Syndromic Surveillance Systems in Acute Care
Kashiouris, M.; O’Horo, J.C.; Pickering, B.W.; Herasevich, V.
2013-01-01
Context Healthcare Electronic Syndromic Surveillance (ESS) is the systematic collection, analysis and interpretation of ongoing clinical data with subsequent dissemination of results, which aid clinical decision-making. Objective To evaluate, classify and analyze the diagnostic performance, strengths and limitations of existing acute care ESS systems. Data Sources All available to us studies in Ovid MEDLINE, Ovid EMBASE, CINAHL and Scopus databases, from as early as January 1972 through the first week of September 2012. Study Selection: Prospective and retrospective trials, examining the diagnostic performance of inpatient ESS and providing objective diagnostic data including sensitivity, specificity, positive and negative predictive values. Data Extraction Two independent reviewers extracted diagnostic performance data on ESS systems, including clinical area, number of decision points, sensitivity and specificity. Positive and negative likelihood ratios were calculated for each healthcare ESS system. A likelihood matrix summarizing the various ESS systems performance was created. Results The described search strategy yielded 1639 articles. Of these, 1497 were excluded on abstract information. After full text review, abstraction and arbitration with a third reviewer, 33 studies met inclusion criteria, reporting 102,611 ESS decision points. The yielded I2 was high (98.8%), precluding meta-analysis. Performance was variable, with sensitivities ranging from 21% –100% and specificities ranging from 5%-100%. Conclusions There is significant heterogeneity in the diagnostic performance of the available ESS implements in acute care, stemming from the wide spectrum of different clinical entities and ESS systems. Based on the results, we introduce a conceptual framework using a likelihood ratio matrix for evaluation and meaningful application of future, frontline clinical decision support systems. PMID:23874359
Liou, Kevin; Negishi, Kazuaki; Ho, Suyen; Russell, Elizabeth A; Cranney, Greg; Ooi, Sze-Yuan
2016-08-01
Global longitudinal strain (GLS) is well validated and has important applications in contemporary clinical practice. The aim of this analysis was to evaluate the accuracy of resting peak GLS in the diagnosis of obstructive coronary artery disease (CAD). A systematic literature search was performed through July 2015 using four databases. Data were extracted independently by two authors and correlated before analyses. Using a random-effect model, the pooled sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, diagnostic odds ratio, and summary area under the curve for GLS were estimated with their respective 95% CIs. Screening of 1,669 articles yielded 10 studies with 1,385 patients appropriate for inclusion in the analysis. The mean age and left ventricular ejection fraction were 59.9 years and 61.1%. On the whole, 54.9% and 20.9% of the patients had hypertension and diabetes, respectively. Overall, abnormal GLS detected moderate to severe CAD with a pooled sensitivity, specificity, positive likelihood ratio, and negative likelihood ratio of 74.4%, 72.1%, 2.9, and 0.35 respectively. The area under the curve and diagnostic odds ratio were 0.81 and 8.5. The mean values of GLS for those with and without CAD were -16.5% (95% CI, -15.8% to -17.3%) and -19.7% (95% CI, -18.8% to -20.7%), respectively. Subgroup analyses for patients with severe CAD and normal left ventricular ejection fractions yielded similar results. Current evidence supports the use of GLS in the detection of moderate to severe obstructive CAD in symptomatic patients. GLS may complement existing diagnostic algorithms and act as an early adjunctive marker of cardiac ischemia. Crown Copyright © 2016. Published by Elsevier Inc. All rights reserved.
Laslett, Mark; Oberg, Birgitta; Aprill, Charles N; McDonald, Barry
2005-01-01
The "centralization phenomenon" (CP) is the progressive retreat of referred pain towards the spinal midline in response to repeated movement testing (a McKenzie evaluation). A previous study suggested that it may have utility in the clinical diagnosis of discogenic pain and may assist patient selection for discography and specific treatments for disc pain. Estimation of the diagnostic predictive power of centralization and the influence of disability and patient distress on diagnostic performance, using provocation discography as a criterion standard for diagnosis, in chronic low back pain patients. This study was a prospective, blinded, concurrent, reference standard-related validity design carried out in a private radiology clinic specializing in diagnosis of chronic spinal pain. Consecutive patients with persistent low back pain were referred to the study clinic by orthopedists and other medical specialists for interventional radiological diagnostic procedures. Patients were typically disabled and displayed high levels of psychosocial distress. The sample included patients with previous lumbar surgery, and most had unsuccessful conservative therapies previously. results of provocation discography. The CP. Psychometric evaluation: Roland-Morris, Zung, Modified Somatic Perception questionnaires, Distress Risk Assessment Method, and 100-mm visual analog scales for pain intensity. Patients received a single physical therapy examination, followed by lumbar provocation discography. Sensitivity, specificity, and likelihood ratios of the CP were estimated in the group as a whole and in subgroups defined by psychometric measures. A total of 107 patients received the clinical examination and discography at two or more levels and post-discography computed tomography. Thirty-eight could not tolerate a full physical examination and were excluded from the main analysis. Disability and pain intensity ratings were high, and distress was common. Sensitivity, specificity, and positive likelihood ratios for centralization observed during repeated movement testing for pain distribution and intensity changes were 40%, 94%, and 6.9 respectively. In the presence of severe disability, sensitivity, specificity, and positive likelihood ratios were 46%, 80%, 3.2 and for distress, 45%, 89%, 4.1. In the subgroups with moderate, minimal, or no disability, sensitivity and specificity were 37%, 100% and for no or minimal distress 35%, 100%. Centralization is highly specific to positive discography but specificity is reduced in the presence of severe disability or psychosocial distress.
2008-04-23
In general, the positive predictive value of screening questionnaires is quite poor when disease prevalence is modest/rare, as in the ex- ample of...of sensitivity, specificity, likelihood ratios and predictive values with disease prevalence . Stat Med 1997;16:981–91. 26. Wolfe J, Erickson DJ
Accuracy of FDG-PET to diagnose lung cancer in a region of endemic granulomatous disease.
Deppen, Stephen; Putnam, Joe B; Andrade, Gabriela; Speroff, Theodore; Nesbitt, Jonathan C; Lambright, Eric S; Massion, Pierre P; Walker, Ron; Grogan, Eric L
2011-08-01
The 18 F-fluorodeoxyglucose-positron emission tomography (FDG-PET) is used to evaluate suspicious pulmonary lesions due to its diagnostic accuracy. The southeastern United States has a high prevalence of infectious granulomatous lung disease, and the accuracy of FDG-PET may be reduced in this population. We examined the diagnostic accuracy of FDG-PET in patients with known or suspected non-small cell lung cancer treated at our institution. A total of 279 patients, identified through our prospective database, underwent an operation for known or suspected lung cancer. Preoperative FDG-PET in 211 eligible patients was defined by standardized uptake value greater than 2.5 or by description ("moderate" or "intense") as avid. Sensitivity, specificity, positive and negative predictive values, likelihood ratios, and decision diagrams were calculated for FDG-PET in all patients and in patients with indeterminate nodules. In all eligible patients (n=211), sensitivity and specificity of FDG-PET were 92% and 40%, respectively. Positive and negative predictive values were 86% and 55%. Overall FDG-PET accuracy to diagnose lung cancer was 81%. Preoperative positive likelihood ratio for FDG-PET diagnosis of lung cancer in this population was 1.5 compared with previously published values of 7.1. In 113 indeterminate lesions, 65% had lung cancer and the sensitivity and specificity were 89% and 40%, respectively. Twenty-four benign nodules (60%) had false positive FDG-PET scans. Twenty-two of 43 benign nodules (51%) were granulomas. In a region with endemic granulomatous diseases, the specificity of FDG-PET for diagnosis of lung cancer was 40%. Clinical decisions and future clinical predictive models for lung cancer must accommodate regional variation of FDG-PET scan results. Copyright © 2011 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.
Warkentin, Theodore E; Sheppard, Jo-Ann I; Linkins, Lori-Ann; Arnold, Donald M; Nazy, Ishac
2017-05-01
Heparin-induced thrombocytopenia (HIT) is a prothrombotic drug reaction caused by platelet-activating anti-PF4/heparin antibodies. Given time-sensitive treatment considerations, a rapid and accurate laboratory test for HIT antibodies is needed. To determine operating characteristics for the HemosIL ® HIT-Ab (PF4/H) , a rapid, on-demand, fully-automated, latex immunoturbidimetric assay (LIA), for diagnosis of HIT. We evaluated LIA sensitivity, specificity, negative (NPV) and positive predictive value (PPV), negative (LR-) and positive likelihood ratio (LR+), using citrated-plasma from 429 patients (prospective cohort study of 4Ts scoring; HIT, n=31), and from consecutive HIT patients (n=125), using reference standard serotonin-release assay (SRA). Comparators included two PF4-dependent enzyme-immunoassays (EIAs). We used stratum-specific likelihood ratios (SSLRs) to determine how differing magnitudes of LIA-positivity influenced post-test probability of HIT. LIA operating characteristics were: sensitivity=97.4% (152/156); specificity=94.0% (374/398); PPV=55.6% (30/54); and NPV=99.7% (374/375). At manufacturers' cutoffs, LIA specificity and PPV were superior to the EIAs. Although a negative LIA pointed strongly against HIT (LR-, 0.034), the post-test probability was ~2% with high 4Ts score. The LIA's LR+ was high (16.0), with SSLRs rising substantially with greater LIA-positivity: 5.7 (1.0-4.9U/mL), 31 (5.0-15.9U/mL), and 128 (≥16U/mL). A LIA-positive result (at 1.0 cutoff) indicated at least 24% HIT probability (low 4Ts score), rising to 90% with high 4Ts score. Although approximately 1 in 40 SRA-positive patients tested LIA-negative, the LIA's high NPV and PPV indicate that this rapid assay is useful for the diagnostic evaluation of HIT, including in low pre-test situations. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.
Theron, Grant; Peter, Jonny; Calligaro, Greg; Meldau, Richard; Hanrahan, Colleen; Khalfey, Hoosain; Matinyenya, Brian; Muchinga, Tapuwa; Smith, Liezel; Pandie, Shaheen; Lenders, Laura; Patel, Vinod; Mayosi, Bongani M.; Dheda, Keertan
2014-01-01
The determinants of Xpert MTB/RIF sensitivity, a widely used PCR test for the diagnosis of tuberculosis (TB) are poorly understood. We compared culture time-to-positivity (TTP; a surrogate of bacterial load), MTB/RIF TB-specific and internal positive control (IPC)-specific CT values, and clinical characteristics in patients with suspected TB who provided expectorated (n = 438) or induced sputum (n = 128), tracheal aspirates (n = 71), bronchoalveolar lavage fluid (n = 152), pleural fluid (n = 76), cerebral spinal fluid (CSF; n = 152), pericardial fluid (n = 131), or urine (n = 173) specimens. Median bacterial load (TTP in days) was the strongest associate of MTB/RIF positivity in each fluid. TTP correlated with CT values in pulmonary specimens but not extrapulmonary specimens (Spearman's coefficient 0.5043 versus 0.1437; p = 0.030). Inhibition affected a greater proportion of pulmonary specimens than extrapulmonary specimens (IPC CT > 34: 6% (47/731) versus 1% (4/381; p < 0.0001). Pulmonary specimens had greater load than extrapulmonary specimens [TTPs (interquartile range) of 11 (7–16) versus 22 (18–33.5) days; p < 0.0001]. HIV-infection was associated with a decreased likelihood of MTB/RIF-positivity in pulmonary specimens but an increased likelihood in extrapulmonary specimens. Mycobacterial load, which displays significant variation across different body compartments, is the main determinant of MTB/RIF-positivity rather than PCR inhibition. MTB/RIF CT is a poor surrogate of load in extrapulmonary specimens. PMID:25014250
Sensitivity of Gram stain in the diagnosis of urethritis in men.
Orellana, M Angeles; Gómez-Lus, M Luisa; Lora, David
2012-06-01
Acute urethritis is among the most common types of sexually transmitted diseases in men. The diagnosis usually requires microscopic evidence of urethritis, but sometimes urethral pathogens are detected in asymptomatic men without such evidence. The aims of this study were to assess the sensitivity of Gram stain in men with urethral symptoms and to relate it to the microorganisms isolated. Between January 2006 and December 2007, 491 urethral samples were analysed. The authors assessed the presence of leukocytes by Gram stain and tested specifically for Chlamydia trachomatis, Ureaplasma urealyticum, Mycoplasma hominis and Trichomonas vaginalis, as well as analysing the results of conventional culture. The percentages of positive samples as a function of Gram category were two or less polymorphonuclear leukocytes (PMNLs)/high-power field (HPF) 25% (92/364), three to four PMNLs/HPF 32% (18/57) and five or more PMNLs/HPF 54% (38/70). Classing samples with more than two PMNLs/HPF as positive, the sensitivity, specificity and positive likelihood ratio for Gram stain were 38% (95% CI 30 to 46), 79% (95% CI 75 to 84) and 1.8 (95% CI 1.4 to 2.4), respectively. On the other hand, taking as positive five or more PMNLs/HPF, the sensitivity, specificity and positive likelihood ratio for Gram stain were 26% (95% CI 18 to 33), 91% (95% CI 87 to 94) and 2.7 (95% CI 1.8 to 4.2), respectively. The sensitivity of Gram stain to Neisseria gonorrhoeae, Chlamydia trachomatis and Ureaplasma urealyticum were 80% (95% CI 64 to 96), 23% (95% CI 8 to 39) and 11% (95% CI 2 to 20), respectively. The low sensitivity of Gram stain means that negative results do not exclude the presence of urethritis in symptomatic patients.
Marroquín, Brett; Boyle, Chloe C.; Nolen-Hoeksema, Susan; Stanton, Annette L.
2016-01-01
Predictions about the future are susceptible to mood-congruent influences of emotional state. However, recent work suggests individuals also differ in the degree to which they incorporate emotion into cognition. This study examined the role of such individual differences in the context of state negative emotion. We examined whether trait tendencies to use negative or positive emotion as information affect individuals' predictions of what will happen in the future (likelihood estimation) and how events will feel (affective forecasting), and whether trait influences depend on emotional state. Participants (N=119) reported on tendencies to use emotion as information (“following feelings”), underwent an emotion induction (negative versus neutral), and made likelihood estimates and affective forecasts for future events. Views of the future were predicted by both emotional state and individual differences in following feelings. Whereas following negative feelings affected most future-oriented cognition across emotional states, following positive feelings specifically buffered individuals' views of the future in the negative emotion condition, and specifically for positive future events, a category of future-event prediction especially important in psychological health. Individual differences may confer predisposition toward optimistic or pessimistic expectations of the future in the context of acute negative emotion, with implications for adaptive and maladaptive functioning. PMID:27041783
Development and validation of a parent-report measure for detection of cognitive delay in infancy.
Schafer, Graham; Genesoni, Lucia; Boden, Greg; Doll, Helen; Jones, Rosamond A K; Gray, Ron; Adams, Eleri; Jefferson, Ros
2014-12-01
To develop a brief, parent-completed instrument (ERIC - Early Report by Infant Caregivers) for detection of cognitive delay in 10- to 24-month-olds born preterm, or of low birthweight, or with perinatal complications, and to establish ERIC's diagnostic properties. Scores for ERIC were collected from the parents of 317 children meeting ≥inclusion criterion (birthweight <1500 g, gestational age <34 completed weeks, 5 min Apgar score <7, or presence of hypoxic-ischaemic encephalopathy) and no exclusion criteria. Children were assessed using a criterion score of below 80 on the Bayley Scales of Infant and Toddler Development-III cognitive scale. Items were retained according to their individual associations with delay. Sensitivity, specificity, and positive and negative predictive values were estimated and a truncated ERIC was developed for use in children <14 months old. ERIC correctly detected developmental delay in 17 out of 18 children in the sample, with 94.4% sensitivity, 76.9% specificity, 19.8% positive predictive value, 99.6% negative predictive value, 4.09 likelihood ratio positive, and 0.07 likelihood ratio negative. ERIC has potential value as a quickly administered diagnostic instrument for the absence of early cognitive delay in 10- to 24-month-old preterm infants and as a screen for cognitive delay. © 2014 Mac Keith Press.
Mohd-Sidik, Sherina; Arroll, Bruce; Goodyear-Smith, Felicity; Zain, Azhar M D
2011-01-01
To determine the diagnostic accuracy of the two questions with help question (TQWHQ) in the Malay language. The two questions are case-finding questions on depression, and a question on whether help is needed was added to increase the specificity of the two questions. This cross sectional validation study was conducted in a government funded primary care clinic in Malaysia. The participants included 146 consecutive women patients receiving no psychotropic drugs and who were Malay speakers. The main outcome measures were sensitivity, specificity, and likelihood ratios of the two questions and help question. The two questions showed a sensitivity of 99% (95% confidence interval 88% to 99.9%) and a specificity of 70% (62% to 78%), respectively. The likelihood ratio for a positive test was 3.3 (2.5 to 4.5) and the likelihood ratio for a negative test was 0.01 (0.00 to 0.57). The addition of the help question to the two questions increased the specificity to 95% (89% to 98%). The two qeustions on depression detected most cases of depression in this study. The questions have the advantage of brevity. The addition of the help question increased the specificity of the two questions. Based on these findings, the TQWHQ can be strongly recommended for detection of depression in government primary care clnics in Malaysia. Translation did not apear to affect the validity of the TQWHQ.
Disclosure of Medical Errors: What Factors Influence How Patients Respond?
Mazor, Kathleen M; Reed, George W; Yood, Robert A; Fischer, Melissa A; Baril, Joann; Gurwitz, Jerry H
2006-01-01
BACKGROUND Disclosure of medical errors is encouraged, but research on how patients respond to specific practices is limited. OBJECTIVE This study sought to determine whether full disclosure, an existing positive physician-patient relationship, an offer to waive associated costs, and the severity of the clinical outcome influenced patients' responses to medical errors. PARTICIPANTS Four hundred and seven health plan members participated in a randomized experiment in which they viewed video depictions of medical error and disclosure. DESIGN Subjects were randomly assigned to experimental condition. Conditions varied in type of medication error, level of disclosure, reference to a prior positive physician-patient relationship, an offer to waive costs, and clinical outcome. MEASURES Self-reported likelihood of changing physicians and of seeking legal advice; satisfaction, trust, and emotional response. RESULTS Nondisclosure increased the likelihood of changing physicians, and reduced satisfaction and trust in both error conditions. Nondisclosure increased the likelihood of seeking legal advice and was associated with a more negative emotional response in the missed allergy error condition, but did not have a statistically significant impact on seeking legal advice or emotional response in the monitoring error condition. Neither the existence of a positive relationship nor an offer to waive costs had a statistically significant impact. CONCLUSIONS This study provides evidence that full disclosure is likely to have a positive effect or no effect on how patients respond to medical errors. The clinical outcome also influences patients' responses. The impact of an existing positive physician-patient relationship, or of waiving costs associated with the error remains uncertain. PMID:16808770
ERIC Educational Resources Information Center
Olson, Jonathan R.; Goddard, H. Wallace
2015-01-01
The purpose of this study was to identify predictors of depressive symptoms among adolescents using concepts drawn from two theoretical models that underlie popular youth-focused programs. Specifically, we assessed the degree to which family-level risk factors increase the likelihood of depressive symptoms, and the degree to which community and/or…
Yu, Zhiyuan; Zheng, Jun; Guo, Rui; Ma, Lu; Li, Mou; Wang, Xiaoze; Lin, Sen; Li, Hao; You, Chao
2017-12-01
Hematoma expansion is independently associated with poor outcome in intracerebral hemorrhage (ICH). Blend sign is a simple predictor for hematoma expansion on non-contrast computed tomography. However, its accuracy for predicting hematoma expansion is inconsistent in previous studies. This meta-analysis is aimed to systematically assess the performance of blend sign in predicting hematoma expansion in ICH. A systematic literature search was conducted. Original studies about predictive accuracy of blend sign for hematoma expansion in ICH were included. Pooled sensitivity, specificity, positive and negative likelihood ratios were calculated. Summary receiver operating characteristics curve was constructed. Publication bias was assessed by Deeks' funnel plot asymmetry test. A total of 5 studies with 2248 patients were included in this meta-analysis. The pooled sensitivity, specificity, positive and negative likelihood ratios of blend sign for predicting hematoma expansion were 0.28, 0.92, 3.4 and 0.78, respectively. The area under the curve (AUC) was 0.85. No significant publication bias was found. This meta-analysis demonstrates that blend sign is a useful predictor with high specificity for hematoma expansion in ICH. Further studies with larger sample size are still necessary to verify the accuracy of blend sign for predicting hematoma expansion. Copyright © 2017 Elsevier B.V. All rights reserved.
Chen, Helen; Bautista, Dianne; Ch'ng, Ying Chia; Li, Wenyun; Chan, Edwin; Rush, A John
2013-06-01
The Edinburgh Postnatal Depression Scale (EPDS) may not be a uniformly valid postnatal depression (PND) screen across populations. We evaluated the performance of a Chinese translation of 10-item (HK-EPDS) and six-item (HK-EPDS-6) versions in post-partum women in Singapore. Chinese-speaking post-partum obstetric clinic patients were recruited for this study. They completed the HK-EPDS, from which we derived the six-item HK-EPDS-6. All women were clinically assessed for PND based on Diagnostic and Statistical Manual, Fourth Edition-Text Revision criteria. Receiver-operator curve (ROC) analyses and likelihood ratio computations informed scale cutoff choices. Clinical fitness was judged by thresholds for internal consistency [α ≥ 0.70] and for diagnostic performance by true-positive rate (>85%), false-positive rate (≤10%), positive likelihood ratio (>1), negative likelihood ratio (<0.2), area under the ROC curve (AUC, ≥90%) and effect size (≥0.80). Based on clinical interview, prevalence of PND was 6.2% in 487 post-partum women. HK-EPDS internal consistency was 0.84. At 13 or more cutoff, the true-positive rate was 86.7%, false-positive rate 3.3%, positive likelihood ratio 26.4, negative likelihood ratio 0.14, AUC 94.4% and effect size 0.81. For the HK-EPDS-6, internal consistency was 0.76. At 8 or more cutoff, we found a true-positive rate of 86.7%, false-positive rate 6.6%, positive likelihood ratio 13.2, negative likelihood ration 0.14, AUC 92.9% and effect size 0.98. The HK-EPDS (cutoff ≥13) and HK-EPDS6 (cutoff ≥8) are fit for PND screening for general population post-partum women. The brief six-item version appears to be clinically suitable for quick screening in Chinese speaking women. Copyright © 2013 Wiley Publishing Asia Pty Ltd.
Horsch, Karla; Pesce, Lorenzo L.; Giger, Maryellen L.; Metz, Charles E.; Jiang, Yulei
2012-01-01
Purpose: The authors developed scaling methods that monotonically transform the output of one classifier to the “scale” of another. Such transformations affect the distribution of classifier output while leaving the ROC curve unchanged. In particular, they investigated transformations between radiologists and computer classifiers, with the goal of addressing the problem of comparing and interpreting case-specific values of output from two classifiers. Methods: Using both simulated and radiologists’ rating data of breast imaging cases, the authors investigated a likelihood-ratio-scaling transformation, based on “matching” classifier likelihood ratios. For comparison, three other scaling transformations were investigated that were based on matching classifier true positive fraction, false positive fraction, or cumulative distribution function, respectively. The authors explored modifying the computer output to reflect the scale of the radiologist, as well as modifying the radiologist’s ratings to reflect the scale of the computer. They also evaluated how dataset size affects the transformations. Results: When ROC curves of two classifiers differed substantially, the four transformations were found to be quite different. The likelihood-ratio scaling transformation was found to vary widely from radiologist to radiologist. Similar results were found for the other transformations. Our simulations explored the effect of database sizes on the accuracy of the estimation of our scaling transformations. Conclusions: The likelihood-ratio-scaling transformation that the authors have developed and evaluated was shown to be capable of transforming computer and radiologist outputs to a common scale reliably, thereby allowing the comparison of the computer and radiologist outputs on the basis of a clinically relevant statistic. PMID:22559651
Novak, Kerri L.; Jacob, Deepti; Kaplan, Gilaad G.; Boyce, Emma; Ghosh, Subrata; Ma, Irene; Lu, Cathy; Wilson, Stephanie; Panaccione, Remo
2016-01-01
Background. Approaches to distinguish inflammatory bowel disease (IBD) from noninflammatory disease that are noninvasive, accurate, and readily available are desirable. Such approaches may decrease time to diagnosis and better utilize limited endoscopic resources. The aim of this study was to evaluate the diagnostic accuracy for gastroenterologist performed point of care ultrasound (POCUS) in the detection of luminal inflammation relative to gold standard ileocolonoscopy. Methods. A prospective, single-center study was conducted on convenience sample of patients presenting with symptoms of diarrhea and/or abdominal pain. Patients were offered POCUS prior to having ileocolonoscopy. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) with 95% confidence intervals (CI), as well as likelihood ratios, were calculated. Results. Fifty-eight patients were included in this study. The overall sensitivity, specificity, PPV, and NPV were 80%, 97.8%, 88.9%, and 95.7%, respectively, with positive and negative likelihood ratios (LR) of 36.8 and 0.20. Conclusion. POCUS can accurately be performed at the bedside to detect transmural inflammation of the intestine. This noninvasive approach may serve to expedite diagnosis, improve allocation of endoscopic resources, and facilitate initiation of appropriate medical therapy. PMID:27446838
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.
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.
The five-factor model of impulsivity-like traits and emotional lability in aggressive behavior.
Dvorak, Robert D; Pearson, Matthew R; Kuvaas, Nicholas J
2013-01-01
Factors that increase automatic psychological processes may result in impulsive action and, consequently, aggressive behavior. The current cross-sectional study examined the association between the five-factor model of impulsivity-like traits (negative urgency, positive urgency, premeditation, perseverance, and sensation seeking), emotional lability, and physically aggressive behaviors among college students (n = 481) in a negative binomial hurdle model. In the logistic portion of the model, emotional lability was related to a higher likelihood of engaging in aggressive acts in the past 6 months. The association between emotional lability and the likelihood of aggressive behavior was moderated by two impulsivity-like traits: negative urgency and positive urgency. Specifically, emotional lability was related to engaging in aggressive acts among those with high negative urgency, and among those with low positive urgency. In the count portion of the model, emotional lability was uniquely related to the number of aggressive acts in the past 6 months. Our results indicate that emotional lability and facets of impulsivity interactively relate to engagement in aggressive behavior, suggesting that these variables be integrated into models of aggression. © 2013 Wiley Periodicals, Inc.
Who Gets Promoted? Gender Differences in Science and Engineering Academia
NASA Astrophysics Data System (ADS)
Olson, Kristen
Using a nationally representative sample of doctoral academic scientists and engineers, this study examines gender differences in the likelihood of having tenure and senior faculty ranks after controlling for academic age, field, doctoral origins, employing educational institution, productivity, postdoctoral positions, work activities, and family characteristics. Logistic regressions show that many of these controls are significant; that biology and employment at comprehensive universities have a gender-specific advantage for women; and that postdoctoral positions, teaching instead of doing administrative work, and having children have a gender-specific disadvantage. Although the statistical methods employed here do not reveal the exact nature of how gender inequities in science and engineering careers arise, the author suggests that they exist.
Dai, Cong; Jiang, Min; Sun, Ming-Jun; Cao, Qin
2018-05-01
Fecal immunochemical test (FIT) is a promising marker for assessment of inflammatory bowel disease activity. However, the utility of FIT for predicting mucosal healing (MH) of ulcerative colitis (UC) patients has yet to be clearly demonstrated. The objective of our study was to perform a diagnostic test accuracy test meta-analysis evaluating the diagnostic accuracy of FIT in predicting MH of UC patients. We systematically searched the databases from inception to November 2017 that evaluated MH in UC. The methodological quality of each study was assessed according to the Quality Assessment of Diagnostic Accuracy Studies checklist. The extracted data were pooled using a summary receiver operating characteristic curve model. Random-effects model was used to summarize the diagnostic odds ratio, sensitivity, specificity, positive likelihood ratio, and negative likelihood ratio. Six studies comprising 625 UC patients were included in the meta-analysis. The pooled sensitivity and specificity values for predicting MH in UC were 0.77 (95% confidence interval [CI], 0.72-0.81) and 0.81 (95% CI, 0.76-0.85), respectively. The FIT level had a high rule-in value (positive likelihood ratio, 3.79; 95% CI, 2.85-5.03) and a moderate rule-out value (negative likelihood ratio, 0.26; 95% CI, 0.16-0.43) for predicting MH in UC. The results of the receiver operating characteristic curve analysis (area under the curve, 0.88; standard error of the mean, 0.02) and diagnostic odds ratio (18.08; 95% CI, 9.57-34.13) also revealed improved discrimination for identifying MH in UC with FIT concentration. Our meta-analysis has found that FIT is a simple, reliable non-invasive marker for predicting MH in UC patients. © 2018 Journal of Gastroenterology and Hepatology Foundation and John Wiley & Sons Australia, Ltd.
Wongwai, Phanthipha; Anupongongarch, Pacharapan; Suwannaraj, Sirinya; Asawaphureekorn, Somkiat
2016-08-01
To evaluate the prevalence of visual impairment of children aged four to six years in Khon Kaen City Municipality, Thailand. The visual acuity test was performed on 1,286 children in kindergarten schools located in Khon Kaen Municipality. The first test of visual acuity was done by trained teachers and the second test by the pediatric ophthalmologist. The prevalence of visual impairment of both tests was recorded including sensitivity, specificity, likelihood ratio, and predictive value of the test by teachers. The causes of visual impairment were also recorded. There were 39 children with visual impairment from the test by the teacher and 12 children from the test by the ophthalmologist. Myopia is the single cause of visual impairment. Mean spherical equivalence is 1.375 diopters (SD = 0.53). Median spherical equivalence is 1.375 diopters (minimum = 0.5, maximum =4). The detection of visual impairment by trained teachers had a sensitivity of 1.00 (95% CI 0.76-1.00), specificity of 0.98 (95% CI 0.97-0.99), likelihood ratio for a positive test 44.58 (95% CI 30.32-65.54), likelihood ratio for a negative test 0.04 (95% CI 0.003-0.60), positive predictive value of 0.31 (95% CI 0.19-0.47), and negative predictive value of 1.00 (95% CI 0.99-1.00). The prevalence of visual impairment among children aged four to six year old is 0.9%. Trained teachers can be examiners for screening purpose.
Gandhi, Rikesh; Silverman, Edward; Courtney, Paul M; Lee, Gwo-Chin
2017-09-01
Identification of the infecting organism is critical to the successful management of deep prosthetic joint infections about the hip and the knee. However, the number of culture specimens and which culture specimens are best to identify these organisms is unknown. We evaluated 113 consecutive patients with infected total hip and total knee arthroplasties and correlated the type of culture specimen and number of specimens taken during surgery to the likelihood of a positive culture result. From these data, we subsequently developed a model to maximize culture yield at the time of surgical intervention. After exclusions, 74 patients meeting the Musculoskeletal Infection Society criteria were left for final analysis. From this cohort, 63 of 74 patients had a positive culture result (85%). The odds of a fluid culture result being positive was 35 of 47 (0.75), whereas the likelihood of tissue cultures yielding a positive result was 164 of 245 (0.67; P = .313). The sample designated "best culture" specimen was the only culture with a positive result in 1 of 48 cases in which a best culture was identified. The optimal number of cultures needed to yield a positive test result was 4 (specificity = 0.61 and sensitivity = 0.63). Increasing the number of samples increases sensitivity but reduces specificity. A minimum of 4 tissue cultures from representative areas is necessary to maximize the chance of identifying the infecting organism during management of the infected total hip and total knee arthroplasties. The designation of the best culture specimen for additional testing is arbitrary and may not be clinically efficacious. Copyright © 2017 Elsevier Inc. All rights reserved.
Bilirubin nomogram for prediction of significant hyperbilirubinemia in north Indian neonates.
Pathak, Umesh; Chawla, Deepak; Kaur, Saranjit; Jain, Suksham
2013-04-01
(i) To construct hour-specific serum total bilirubin (STB) nomogram in neonates born at =35 weeks of gestation; (ii)To evaluate efficacy of pre-discharge bilirubin measurement in predicting hyperbilirubinemia needing treatment. Diagnostic test performance in a prospective cohort study. Teaching hospital in Northern India. Healthy neonates with gestation =35 weeks or birth weight =2000 g. Serum total bilirubin was measured in all enrolled neonates at 24 ± 6, 72-96 and 96-144 h of postnatal age and when indicated clinically. Neonates were followed up during hospital stay and after discharge till completion of 7th postnatal day. Key outcome was significant hyperbilirubinemia (SHB) defined as need of phototherapy based on modified American Academy of Pediatrics (AAP) guidelines. In neonates born at 38 or more weeks of gestation middle line and in neonates born at 37 or less completed weeks of gestation, lower line of phototherapy thresholds were used to initiate phototherapy. For construction of nomogram, STB values were clubbed in six-hour epochs (age ± 3 hours) for postnatal age up to 48 h and twelve-hour epochs (age ± 6 hours) for age beyond 48 h. Predictive ability of the nomogram was assessed by calculating sensitivity, specificity, positive predictive value, negative predictive value and likelihood ratio, by plotting receiver-operating characteristics (ROC) curve and calculating c-statistic. 997 neonates (birth weight: 2627 ± 536 g, gestation: 37.8 ± 1.5 weeks) were enrolled, of which 931 completed followup. Among enrolled neonates 344 (34.5%) were low birth weight. Rate of exclusive breastfeeding during hospital stay was more than 80%. Bilirubin nomogram was constructed using 40th, 75th and 95th percentile values of hour-specific bilirubin. Pre-discharge STB of =95th percentile was assigned to be in high-risk zone, between 75th and 94th centile in upper-intermediate risk zone, between 40th and 74th centile in lower-intermediate risk zone and below 40th percentile in low-risk zone. Among 49 neonates with pre-discharge STB in high risk zone. 34 developed SHB (positive predictive value: 69.4%, sensitivity: 17.1%, positive likelihood ratio: 8.26). Among 342 neonates with pre-discharge STB in low risk zone, 32 developed PHB (negative predictive value: 90.6% and specificity: 42.5%, positive likelihood ratio: 0.37). Area under curve for this risk assessment strategy was 0.73. Hour-specific bilirubin nomogram and STB measurement can be used for predicting subsequent need of phototherapy. Further studies are needed to validate performance of risk demarcation zones defined in this hour-specific bilirubin nomogram.
Chaudhari, Pradip P; Monuteaux, Michael C; Shah, Pinkey; Bachur, Richard G
2017-07-01
The presence of leukocyte esterase by urine dipstick and microscopic pyuria are both indicators of possible urinary tract infection. The effect of urine concentration on the diagnostic performance of the urinalysis for pediatric urinary tract infection has not been studied. Our objective is to determine whether the urinalysis performance for detecting urinary tract infection varies by urine concentration as measured by specific gravity. This was a retrospective cross-sectional study of the urine laboratory results of children younger than 13 years who presented to the emergency department during 68 months and had a paired urinalysis and urine culture obtained. Urinary tract infection was defined as pure growth of a uropathogen at standard culture thresholds. Test characteristics were calculated across 4 specific gravity groups (1.000 to 1.010, 1.011 to 1.020, 1.021 to 1.030, and >1.030). In total, 14,971 cases were studied. Median age was 1.5 years (interquartile range 0.4 to 5.5 years) and 60% were female patients. Prevalence of urinary tract infection was 7.7%. For the presence of leukocyte esterase and a range of pyuria cut points, the positive likelihood ratios decreased with increasing specific gravity. From most dilute to most concentrated urine, the positive likelihood ratio decreased from 12.1 (95% confidence interval [CI] 10.7 to 13.7) to 4.2 (95% CI 3.0 to 5.8) and 9.5 (95% CI 8.6 to 10.6) to 5.5 (95% CI 3.3 to 9.1) at a threshold of greater than or equal to 5 WBCs per high-power field and presence of leukocyte esterase, respectively. The negative likelihood ratios increased with increasing specific gravity for leukocyte esterase and microscopic pyuria. For the detection of pediatric urinary tract infection, the diagnostic performance of both dipstick leukocyte esterase and microscopic pyuria varies by urine concentration, and therefore the specific gravity should be considered when the urinalysis is interpreted. Copyright © 2016 American College of Emergency Physicians. Published by Elsevier Inc. All rights reserved.
Schaap, Jeroen; Kauling, Robert M; Boekholdt, S Matthijs; Nieman, Koen; Meijboom, W Bob; Post, Martijn C; Van der Heyden, Jan A; de Kroon, Thom L; van Es, H Wouter; Rensing, Benno J; Verzijlbergen, J Fred
2013-07-01
Hybrid myocardial perfusion imaging with single photon emission computed tomography (SPECT) and CT coronary angiography (CCTA) has the potential to play a major role in patients with non-conclusive SPECT or CCTA results. We evaluated the performance of hybrid SPECT/CCTA vs. standalone SPECT and CCTA for the diagnosis of significant coronary artery disease (CAD) in patients with an intermediate to high pre-test likelihood of CAD. In total, 98 patients (mean age 62.5 ± 10.1 years, 68.4% male) with stable anginal complaints and a median pre-test likelihood of 87% (range 22-95%) were prospectively included in this study. Hybrid SPECT/CCTA was performed prior to conventional coronary angiography (CA) including fractional flow reserve (FFR) measurements. Hybrid analysis was performed by combined interpretation of SPECT and CCTA images. The sensitivity, specificity, positive (PPV), and negative (NPV) predictive values were calculated for standalone SPECT, CCTA, and hybrid SPECT/CCTA on per patient level, using an FFR <0.80 as a reference for significant CAD. Significant CAD was demonstrated in 56 patients (57.9%). Non-conclusive SPECT or CCTA results were found in 32 (32.7%) patients. SPECT had a sensitivity of 93%, specificity 79%, PPV 85%, and NPV 89%. CCTA had a sensitivity of 98%, specificity 62%, PPV 77%, and NPV 96%. Hybrid analysis of SPECT and CCTA improved the overall performance: sensitivity, specificity, PPV, and NPV for the presence of significant CAD to 96, 95, 96, and 95%, respectively. In > 40% of the patients with a high pre-test likelihood no significant CAD was demonstrated, emphasizing the value of accurate pre-treatment cardiovascular imaging. Hybrid SPECT/CCTA was able to accurately diagnose and exclude significant CAD surpassing standalone myocardial SPECT and CCTA, vs. a reference standard of FFR measurements.
Roberson, Nathaniel P; Dillman, Jonathan R; O'Hara, Sara M; DeFoor, William R; Reddy, Pramod P; Giordano, Richard M; Trout, Andrew T
2018-07-01
The incidence of pediatric nephrolithiasis in the United States is increasing. There is a paucity of literature comparing the diagnostic performance of computed ultrasound (US) to tomography (CT) in the pediatric population. To determine the diagnostic performance of renal US for nephrolithiasis in children using a clinical effectiveness approach. Institutional review board approval with a waiver of informed consent was obtained for this retrospective, HIPAA-complaint investigation. Billing records and imaging reports were used to identify children (≤18 years old) evaluated for nephrolithiasis by both US and unenhanced CT within 24 h between March 2012 and March 2017. Imaging reports were reviewed for presence, number, size and location of kidney stones. Diagnostic performance of US (reference standard=CT) was calculated per renal unit (left/right kidney) and per renal sector (four sectors per kidney). For sector analysis, US was considered truly positive if a stone was identified at CT in the same or an adjacent sector. There were 68 renal stones identified by CT in 30/69 patients (43%). Mean patient age was 14.7±3.6 years, and 35 were boys. For detecting nephrolithiasis in any kidney, US was 66.7% (48.8-80.8%) sensitive and 97.4% (86.8-99.9%) specific (positive predictive value=95.2% [77.3-99.8%], negative predictive value=79.2% [65.7-88.3%], positive likelihood ratio=26.0). Per renal sector, US was 59.7% (46.7-71.4%) sensitive and 97.4% (95.5-98.5%) specific (positive predictive value=72.3% [58.2-83.1%], negative predictive value=95.4% [93.2-96.9%], positive likelihood ratio=22.5). Of the 30 stones not detected by US, only 3 were >3 mm at CT. In clinical practice, US has high specificity for detecting nephrolithiasis in children but only moderate sensitivity and false negatives are common.
Trainor, Kate; Pinnington, Mark A
2011-03-01
It has been proposed that neurodynamic examination can assist differential diagnosis of upper/mid lumbar nerve root compression; however, the diagnostic validity of many of these tests has yet to be established. This pilot study aimed to establish the diagnostic validity of the slump knee bend neurodynamic test for upper/mid lumbar nerve root compression in subjects with suspected lumbosacral radicular pain. Two independent examiners performed the slump knee bend test on subjects with radicular leg pain. Inter-tester reliability was calculated using the kappa coefficient. Slump knee bend test results were compared with magnetic resonance imaging findings, and diagnostic accuracy measures were calculated including sensitivity, specificity, predictive values and likelihood ratios. Orthopaedic spinal clinic, secondary care. Sixteen patients with radicular leg pain. All four subjects with mid lumbar nerve root compression on magnetic resonance imaging were correctly identified with the slump knee bend test; however, it was falsely positive in two individuals without the condition. Inter-tester reliability for the slump knee bend test using the kappa coefficient was 0.71 (95% confidence interval 0.33 to 1.0). Diagnostic validity calculations for the slump knee bend test (95% confidence intervals) were: sensitivity, 100% (40 to 100%); specificity, 83% (52 to 98%); positive predictive value, 67% (22 to 96%); negative predictive value, 100% (69 to 100%); positive likelihood ratio, 6.0 (1.58 to 19.4); and negative likelihood ratio, 0 (0 to 0.6). Results indicate good inter-tester reliability and suggest that the slump knee bend test has potential to be a useful clinical test for identifying patients with mid lumbar nerve root compression. Further investigation is needed on larger numbers of patients to confirm these findings. Copyright © 2010 Chartered Society of Physiotherapy. Published by Elsevier Ltd. All rights reserved.
Vinci, Christine; Li, Liang; Wu, Cai; Lam, Cho Y; Guo, Lin; Correa-Fernández, Virmarie; Spears, Claire A; Hoover, Diana S; Etcheverry, Paul E; Wetter, David W
2017-11-01
Individuals attempting to quit smoking typically have poor success rates, and the majority fail to maintain long-term abstinence. Although a large body of evidence documents the impact of negative affect on reducing abstinence, there is a much smaller body of research on positive emotions, which could be an important mechanism that is associated with successful cessation. As such, this study examined positive emotions in real-time via ecological momentary assessment (EMA) to determine whether discrete positive emotions were uniquely related to 2 cessation milestones: quit day lapse and first lapse. Participants were 391 smokers who received tobacco cessation treatment. EMAs were completed pre- and postquit, and positive emotion was assessed with 3 items (enthusiastic, happy, and relaxed) rated on 5-point Likert scales. Analyses examined the associations of the means and slopes of each emotion on the current day with the likelihood of lapse on the following day. When controlling for relevant covariates, prequit positive emotions were not related to quit day lapse. However, postquit positive emotions were associated with first lapse. Specifically, high levels of happiness and relaxation, as well as increasing levels of enthusiasm, happiness, and relaxation were related to a lower likelihood of next day lapse. These are some of the first real-time, real-world data to demonstrate that distinct positive emotions are associated with a lower risk of lapse during the postquit period among smokers attempting to quit. (PsycINFO Database Record (c) 2017 APA, all rights reserved).
Ibáñez-Sanz, Gemma; Garcia, Montse; Rodríguez-Moranta, Francisco; Binefa, Gemma; Gómez-Matas, Javier; Domènech, Xènia; Vidal, Carmen; Soriano, Antonio; Moreno, Víctor
2016-10-01
The most common side effect in population screening programmes is a false-positive result which leads to unnecessary risks and costs. To identify factors associated with false-positive results in a colorectal cancer screening programme with the faecal immunochemical test (FIT). Cross-sectional study of 472 participants with a positive FIT who underwent colonoscopy for confirmation of diagnosis between 2013 and 2014. A false-positive result was defined as having a positive FIT (≥20μg haemoglobin per gram of faeces) and follow-up colonoscopy without intermediate/high-risk lesions or cancer. Women showed a two-fold increased likelihood of a false-positive result compared with men (adjusted OR, 2.3; 95%CI, 1.5-3.4), but no female-specific factor was identified. The other variables associated with a false-positive result were successive screening (adjusted OR, 1.5; 95%CI, 1.0-2.2), anal disorders (adjusted OR, 3.1; 95%CI, 2.1-4.5) and the use of proton pump inhibitors (adjusted OR, 1.8; 95%CI, 1.1-2.9). Successive screening and proton pump inhibitor use were associated with FP in men. None of the other drugs were related to a false-positive FIT. Concurrent use of proton pump inhibitors at the time of FIT might increase the likelihood of a false-positive result. Further investigation is needed to determine whether discontinuing them could decrease the false-positive rate. Copyright © 2016 Editrice Gastroenterologica Italiana S.r.l. Published by Elsevier Ltd. All rights reserved.
Tanaka, Ryo; Umehara, Takuya; Fujimura, Takafumi; Ozawa, Junya
2016-12-01
To develop and assess a clinical prediction rule (CPR) to predict declines in activities of daily living (ADL) at 6 months after surgery for hip fracture repair. Prospective, cohort study. From hospital to home. Patients (N=104) with hip fractures after surgery. Not applicable. ADL were assessed using the Barthel Index at 6 months after surgery. At 6 months after surgery, 86 patients (82.6%) were known to be alive, 1 patient (1.0%) had died, and 17 (16.3%) were lost to follow-up. Thirty-two patients (37.2%) did not recover their ADL at 6 months after surgery to levels before fracture. The classification and regression trees methodology was used to develop 2 models to predict a decline in ADL: (1) model 1 included age, type of fracture, and care level before fracture (sensitivity=75.0%, specificity=81.5%, positive predictive value=70.6%, positive likelihood ratio=4.050); and (2) model 2 included the degree of independence 2 weeks postsurgery for ADL chair transfer, ADL ambulation, and age (sensitivity=65.6%, specificity=87.0%, positive predictive value=75.0%, positive likelihood ratio=5.063). The areas under the receiver operating characteristic curves of both CPR models were .825 (95% confidential interval, .728-.923) and .790 (95% confidence interval, .683-.897), respectively. CPRs with moderate accuracy were developed to predict declines in ADL at 6 months after surgery for hip fracture repair. Copyright © 2016 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.
O'Brien, D J; Fierke, J S; Cooley, T M; Fitzgerald, S D; Cosgrove, M K; Schmitt, S M
2013-11-01
Risks of bovine tuberculosis (bTB) transmission from free-ranging wildlife to livestock remain a concern in the United States, in both known endemic areas and where spillover from recently-infected livestock herds occurs. Federal agriculture officials in the United States (US) have recommended surveillance of non-cervid furbearers to determine whether free-ranging wildlife in the vicinity of cattle herd breakdowns are bTB infected, yet the efficacy of common diagnostic tests in these species is largely unknown. We calculated the sensitivity, specificity, predictive values and positive likelihood ratios for bTB infection in carcasses of sixteen species of furbearers tested via: (i) the presence of gross lesions compatible with bTB; (ii) histopathology consistent with bTB; and (iii) the presence of acid-fast bacilli (AFB) on histopathology. The gold standard comparison test was mycobacterial culture of cranial ± visceral lymph nodes pooled for each animal. Forty-two animals distributed across six species cultured bTB positive from among 1522 furbearers tested over thirteen years. The sensitivity of all three tests was poor (10%, 22% and 24% for gross lesions, AFB and histopathology, respectively), while specificities (all ≥ 99%) and negative predictive values (all ≥ 97%) were high. Positive predictive values varied widely (31-75%). Likelihood ratios for culture positivity given a positive test result showed AFB on histopathology to be the most reliable test, and gross lesions the least, though confidence intervals were wide and overlapping. While non-cervid furbearers may prove useful in North American bTB surveillance, wildlife managers should be aware of factors that may abate their utility and complicate interpretation of surveillance. © 2013 Blackwell Verlag GmbH.
Identifying Patients With Vesicovaginal Fistula at High Risk of Urinary Incontinence After Surgery
Bengtson, Angela M.; Kopp, Dawn; Tang, Jennifer H.; Chipungu, Ennet; Moyo, Margaret; Wilkinson, Jeffrey
2016-01-01
Objective To develop a risk score to identify women with vesicovaginal fistula at high risk of residual urinary incontinence after surgical repair. Methods We conducted a prospective cohort study among 401 women undergoing their first vesicovaginal fistula repair at a referral fistula repair center in Lilongwe, Malawi, between September 2011 and December 2014, who returned for follow-up within 120 days of surgery. We used logistic regression to develop a risk score to identify women with high likelihood of residual urinary incontinence, defined as incontinence grade 2-5 within 120 days of vesicovaginal fistula repair, based on preoperative clinical and demographic characteristics (age, number of years with fistula, HIV status, body mass index, previous repair surgery at an outside facility, revised Goh Classification, Goh vesicovaginal fistula size, circumferential fistula, vaginal scaring, bladder size, and urethral length). The sensitivity, specificity, positive and negative predictive values of the risk score at each cut-point were assessed. Results Overall, 11 (3%) women had unsuccessful fistula closure. Of those with successful fistula closure (n=372), 85 (23%) experienced residual incontinence. A risk score cut-point of 20 had sensitivity 82% (95% CI 72%, 89%) and specificity 63% (95% CI 57%, 69%) to potentially identify women with residual incontinence. In our population, the positive predictive value for a risk score cut-point of _20 or higher was 43% (95% CI 36%, 51%) and the negative predictive value was 91% (95% CI 86%, 94%). Forty-eight percent of our study population had a risk score ≥20 and therefore, would have been identified for further intervention. Conclusions A risk score 20 or higher was associated with an increased likelihood of residual incontinence, with satisfactory sensitivity and specificity. If validated in alternative settings, the risk score could be used to refer women with high likelihood of postoperative incontinence to more experienced surgeons. PMID:27741181
Kim, Hye Jeong; Kwak, Mi Kyung; Choi, In Ho; Jin, So-Young; Park, Hyeong Kyu; Byun, Dong Won; Suh, Kyoil; Yoo, Myung Hi
2018-02-23
The aim of this study was to address the role of the elasticity index as a possible predictive marker for detecting papillary thyroid carcinoma (PTC) and quantitatively assess shear wave elastography (SWE) as a tool for differentiating PTC from benign thyroid nodules. One hundred and nineteen patients with thyroid nodules undergoing SWE before ultrasound-guided fine needle aspiration and core needle biopsy were analyzed. The mean (EMean), minimum (EMin), maximum (EMax), and standard deviation (ESD) of SWE elasticity indices were measured. Among 105 nodules, 14 were PTC and 91 were benign. The EMean, EMin, and EMax values were significantly higher in PTCs than benign nodules (EMean 37.4 in PTC vs. 23.7 in benign nodules, p = 0.005; EMin 27.9 vs. 17.8, p = 0.034; EMax 46.7 vs. 31.5, p < 0.001). The EMean, EMin, and EMax were significantly associated with PTC with diagnostic odds ratios varying from 6.74 to 9.91, high specificities (86.4%, 86.4%, and 88.1%, respectively), and positive likelihood ratios (4.21, 3.69, and 4.82, respectively). The ESD values were significantly higher in PTC than in benign nodules (6.3 vs. 2.6, p < 0.001). ESD had the highest specificity (96.6%) when applied with a cut-off value of 6.5 kPa. It had a positive likelihood ratio of 14.75 and a diagnostic odds ratio of 28.50. The shear elasticity index of ESD, with higher likelihood ratios for PTC, will probably identify nodules that have a high potential for malignancy. It may help to identify and select malignant nodules, while reducing unnecessary fine needle aspiration and core needle biopsies of benign nodules.
Smith, M A; Dyson, S J; Murray, R C
2012-11-01
To determine the reliability of 2 magnetic resonance imaging (MRI) systems for detection of cartilage and bone lesions of the equine fetlock. To test the hypotheses that lesions in cartilage, subchondral and trabecular bone of the equine fetlock verified using histopathology can be detected on high- and low-field MR images with a low incidence of false positive or negative results; that low-field images are less reliable than high-field images for detection of cartilage lesions; and that combining results of interpretation from different pulse sequences increases detection of cartilage lesions. High- and low-field MRI was performed on 19 limbs from horses identified with fetlock lameness prior to euthanasia. Grading systems were used to score cartilage, subchondral and trabecular bone on MR images and histopathology. Sensitivity and specificity were calculated for images. High-field T2*-weighted gradient echo (T2*W-GRE) and low-field T2-weighted fast spin echo (T2W-FSE) images had high sensitivity but low specificity for detection of cartilage lesions. All pulse sequences had high sensitivity and low-moderate specificity for detection of subchondral bone lesions and moderate sensitivity and moderate-high specificity for detection of trabecular bone lesions (histopathology as gold standard). For detection of lesions of trabecular bone low-field T2*W-GRE images had higher sensitivity and specificity than T2W-FSE images. There is high likelihood of false positive results using high- or low-field MRI for detection of cartilage lesions and moderate-high likelihood of false positive results for detection of subchondral bone lesions compared with histopathology. Combining results of interpretation from different pulse sequences did not increase detection of cartilage lesions. MRI interpretation of trabecular bone was more reliable than cartilage or subchondral bone in both MR systems. Independent interpretation of a variety of pulse sequences may maximise detection of cartilage and bone lesions in the fetlock. Clinicians should be aware of potential false positive and negative results. © 2012 EVJ Ltd.
Good, Ryan J; Leroue, Matthew K; Czaja, Angela S
2018-06-07
Noninvasive positive pressure ventilation (NIPPV) is increasingly used in critically ill pediatric patients, despite limited data on safety and efficacy. Administrative data may be a good resource for observational studies. Therefore, we sought to assess the performance of the International Classification of Diseases, Ninth Revision procedure code for NIPPV. Patients admitted to the PICU requiring NIPPV or heated high-flow nasal cannula (HHFNC) over the 11-month study period were identified from the Virtual PICU System database. The gold standard was manual review of the electronic health record to verify the use of NIPPV or HHFNC among the cohort. The presence or absence of a NIPPV procedure code was determined by using administrative data. Test characteristics with 95% confidence intervals (CIs) were generated, comparing administrative data with the gold standard. Among the cohort ( n = 562), the majority were younger than 5 years, and the most common primary diagnosis was bronchiolitis. Most (82%) required NIPPV, whereas 18% required only HHFNC. The NIPPV code had a sensitivity of 91.1% (95% CI: 88.2%-93.6%) and a specificity of 57.6% (95% CI: 47.2%-67.5%), with a positive likelihood ratio of 2.15 (95% CI: 1.70-2.71) and negative likelihood ratio of 0.15 (95% CI: 0.11-0.22). Among our critically ill pediatric cohort, NIPPV procedure codes had high sensitivity but only moderate specificity. On the basis of our study results, there is a risk of misclassification, specifically failure to identify children who require NIPPV, when using administrative data to study the use of NIPPV in this population. Copyright © 2018 by the American Academy of Pediatrics.
Assessment of articular disc displacement of temporomandibular joint with ultrasound.
Razek, Ahmed Abdel Khalek Abdel; Al Mahdy Al Belasy, Fouad; Ahmed, Wael Mohamed Said; Haggag, Mai Ahmed
2015-06-01
To assess pattern of articular disc displacement in patients with internal derangement (ID) of temporomandibular joint (TMJ) with ultrasound. Prospective study was conducted upon 40 TMJ of 20 patients (3 male, 17 female with mean age of 26.1 years) with ID of TMJ. They underwent high-resolution ultrasound and MR imaging of TMJ. The MR images were used as the gold standard for calculating sensitivity, specificity, accuracy, positive predictive value (PPV), negative predictive value (NPV), positive likelihood ratio (PLR), and negative likelihood ratio (NLR) of ultrasound for diagnosis of anterior or sideway displacement of the disc. The anterior displaced disc was seen in 26 joints at MR and 22 joints at ultrasound. The diagnostic efficacy of ultrasound for anterior displacement has sensitivity of 79.3 %, specificity of 72.7 %, accuracy of 77.5 %, PPV of 88.5 %, NPV of 57.1 %, PLR of 2.9 and NLR of 0.34. The sideway displacement of disc was seen in four joints at MR and three joints at ultrasound. The diagnostic efficacy of ultrasound for sideway displacement has a sensitivity of 75 %, specificity of 63.6 %, accuracy of 66.7 %, PPV of 42.8, NPV of 87.5 %, PLR of 2.06, and NLR of 0.39. We concluded that ultrasound is a non-invasive imaging modality used for assessment of anterior and sideway displacement of the articular disc in patients with ID of TMJ.
Validation of a school-based amblyopia screening protocol in a kindergarten population.
Casas-Llera, Pilar; Ortega, Paula; Rubio, Inmaculada; Santos, Verónica; Prieto, María J; Alio, Jorge L
2016-08-04
To validate a school-based amblyopia screening program model by comparing its outcomes to those of a state-of-the-art conventional ophthalmic clinic examination in a kindergarten population of children between the ages of 4 and 5 years. An amblyopia screening protocol, which consisted of visual acuity measurement using Lea charts, ocular alignment test, ocular motility assessment, and stereoacuity with TNO random-dot test, was performed at school in a pediatric 4- to 5-year-old population by qualified healthcare professionals. The outcomes were validated in a selected group by a conventional ophthalmologic examination performed in a fully equipped ophthalmologic center. The ophthalmologic evaluation was used to confirm whether or not children were correctly classified by the screening protocol. The sensitivity and specificity of the test model to detect amblyopia were established. A total of 18,587 4- to 5-year-old children were subjected to the amblyopia screening program during the 2010-2011 school year. A population of 100 children were selected for the ophthalmologic validation screening. A sensitivity of 89.3%, specificity of 93.1%, positive predictive value of 83.3%, negative predictive value of 95.7%, positive likelihood ratio of 12.86, and negative likelihood ratio of 0.12 was obtained for the amblyopia screening validation model. The amblyopia screening protocol model tested in this investigation shows high sensitivity and specificity in detecting high-risk cases of amblyopia compared to the standard ophthalmologic examination. This screening program may be highly relevant for amblyopia screening at schools.
Liu, W; Yin, W; Zhang, R; Li, J; Zheng, Y
2015-06-01
The aim of this study was to evaluate the predictive value of panoramic radiography on inferior alveolar nerve (IAN) injury after extraction of the mandibular third molar. Relevant studies up to 1 June 2014 that discussed the association of panoramic radiography signs and post-mandibular third molar extraction IAN injury were systematically retrieved from the databases of PubMed, Embase, Springerlink, Web of Science and Cochrane library. The effect size of pooled sensitivity, specificity, positive likelihood ratios (PLR), negative likelihood ratios (NLR) and diagnostic odds ratio (DOR) with their 95% confidence intervals (CI) were statistically analysed with Meta-disc 1.4 software. Nine articles were included in this meta-analysis. The pooled estimates of sensitivity and specificity were 0.56 (95% CI: 0.50-0.61) and 0.86 (95% CI: 0.84-0.87), respectively. The overall PLR was 3.46 (95% CI: 2.02-5.92) and overall NLR was 0.58 (95% CI: 0.45-0.73). The pooled estimate of DOR was 6.49 (95% CI: 2.92-14.44). The area under the summary receiver operating characteristic curve was 0.7143 ± 0.0604. The meta-analysis indicated that interpretation of panoramic radiography based on darkening of the root had a high specificity in predicting IAN injury after mandibular third molar extraction. However, the ability of this panoramic radiography marker to detect true positive IAN injury was not satisfactory. © 2015 Australian Dental Association.
Cunningham, Shala
2013-01-01
Objective: The purpose of this study was to estimate the diagnostic accuracy of the ScreenAssist Lumbar Questionnaire (SALQ) to determine the presence of non-musculoskeletal pain or emergent musculoskeletal pain, in terms of its sensitivity and specificity, when compared with the assessment and diagnosis made by primary care providers. Methods: Subjects were patients presenting to a primary care physician’s office with the main complaint of low back pain. SALQ data were collected within 24 hours of the appointment. A 2-month post-visit chart review was performed in order to compare scores and recommendations made by the questionnaire with the assessment and diagnosis made by the physician. Results: The SALQ demonstrated a sensitivity of 100% (95% CI = 0.445–1.0) and specificity of 92% (95% CI = 0.831–0.920). The negative likelihood ratio was 0.11 (95% CI = 0.01–1.54) and the positive likelihood ratio was 9.36 (95% CI = 2.78–32). If the SALQ was positive, the post-test probability was 0.60. If the SALQ was negative, the post-test probability was 0.017. Discussion: Results from this study suggest that the SALQ can be used as an adjunct to the subjective history taking in a physical therapy evaluation to assist in the recognition of non-musculoskeletal or emergent musculoskeletal conditions requiring referral. PMID:24421613
Modeling abundance effects in distance sampling
Royle, J. Andrew; Dawson, D.K.; Bates, S.
2004-01-01
Distance-sampling methods are commonly used in studies of animal populations to estimate population density. A common objective of such studies is to evaluate the relationship between abundance or density and covariates that describe animal habitat or other environmental influences. However, little attention has been focused on methods of modeling abundance covariate effects in conventional distance-sampling models. In this paper we propose a distance-sampling model that accommodates covariate effects on abundance. The model is based on specification of the distance-sampling likelihood at the level of the sample unit in terms of local abundance (for each sampling unit). This model is augmented with a Poisson regression model for local abundance that is parameterized in terms of available covariates. Maximum-likelihood estimation of detection and density parameters is based on the integrated likelihood, wherein local abundance is removed from the likelihood by integration. We provide an example using avian point-transect data of Ovenbirds (Seiurus aurocapillus) collected using a distance-sampling protocol and two measures of habitat structure (understory cover and basal area of overstory trees). The model yields a sensible description (positive effect of understory cover, negative effect on basal area) of the relationship between habitat and Ovenbird density that can be used to evaluate the effects of habitat management on Ovenbird populations.
Robert, Jérôme; Pantel, Alix; Merens, Audrey; Meiller, Elodie; Lavigne, Jean-Philippe; Nicolas-Chanoine, Marie-Hélène
2017-01-17
Carbapenemase-producing Enterobacteriaceae (CPE) are difficult to identify among carbapenem non-susceptible Enterobacteriaceae (NSE). We designed phenotypic strategies giving priority to high sensitivity for screening putative CPE before further testing. Presence of carbapenemase-encoding genes in ertapenem NSE (MIC > 0.5 mg/l) consecutively isolated in 80 French laboratories between November 2011 and April 2012 was determined by the Check-MDR-CT103 array method. Using the Mueller-Hinton (MH) disk diffusion method, clinical diameter breakpoints of carbapenems other than ertapenem, piperazicillin+tazobactam, ticarcillin+clavulanate and cefepime as well as diameter cut-offs for these antibiotics and temocillin were evaluated alone or combined to determine their performances (sensitivity, specificity, positive and negative likelihood ratios) for identifying putative CPE among these ertapenem-NSE isolates. To increase the screening specificity, these antibiotics were also tested on cloxacillin-containing MH when carbapenem NSE isolates belonged to species producing chromosomal cephalosporinase (AmpC) but Escherichia coli. Out of the 349 ertapenem NSE, 52 (14.9%) were CPE, including 39 producing OXA-48 group carbapenemase, eight KPC and five MBL. A screening strategy based on the following diameter cut offs, ticarcillin+clavulanate <15 mm, temocillin <15 mm, meropenem or imipenem <22 mm, and cefepime <26 mm, showed 100% sensitivity and 68.1% specificity with the better likelihood ratios combination. The specificity increased when a diameter cut-off <32 mm for imipenem (76.1%) or meropenem (78.8%) further tested on cloxacillin-containing MH was added to the previous strategy for AmpC-producing isolates. The proposed strategies that allowed for increasing the likelihood of CPE among ertapenem-NSE isolates should be considered as a surrogate for carbapenemase production before further CPE confirmatory testing.
Simental-Mendía, Luis E; Simental-Mendía, Esteban; Rodríguez-Hernández, Heriberto; Rodríguez-Morán, Martha; Guerrero-Romero, Fernando
2016-01-01
Introduction and aim. Given that early identification of non-alcoholic fatty liver disease (NAFLD) is an important issue for primary prevention of hepatic disease, the objectives of this study were to evaluate the efficacy of the product of triglyceride and glucose levels (TyG) for screening simple steatosis and non-alcoholic steatohepatitis (NASH) in asymptomatic women, and to compare its efficacy vs. other biomarkers for recognizing NAFLD. Asymptomatic women aged 20 to 65 years were enrolled into a cross-sectional study. The optimal values of TyG, for screening simple steatosis and NASH were established on a Receiver Operating Characteristic scatter plot; the sensitivity, specificity, and likelihood ratios of TyG index were estimated versus liver biopsy. According sensitivity and specificity, the efficacy of TyG was compared versus the well-known clinical biomarkers for recognizing NAFLD. A total of 50 asymptomatic women were enrolled. The best cutoff point of TyG for screening simple steatosis was 4.58 (sensitivity 0.94, specificity 0.69); in addition, the best cutoff point of TyG index for screening NASH was 4.59 (sensitivity 0.87, specificity 0.69). The positive and negative likelihood ratios were 3.03 and 0.08 for simple steatosis, and 2.80 and 0.18 for NASH. As compared versus SteatoTest, NashTest, Fatty liver index, and Algorithm, the TyG showed to be the best test for screening. TyG has high sensitivity and low negative likelihood ratio; as compared with other clinical biomarkers, the TyG showed to be the best test for screening simple steatosis and NASH.
A Likelihood-Based Framework for Association Analysis of Allele-Specific Copy Numbers.
Hu, Y J; Lin, D Y; Sun, W; Zeng, D
2014-10-01
Copy number variants (CNVs) and single nucleotide polymorphisms (SNPs) co-exist throughout the human genome and jointly contribute to phenotypic variations. Thus, it is desirable to consider both types of variants, as characterized by allele-specific copy numbers (ASCNs), in association studies of complex human diseases. Current SNP genotyping technologies capture the CNV and SNP information simultaneously via fluorescent intensity measurements. The common practice of calling ASCNs from the intensity measurements and then using the ASCN calls in downstream association analysis has important limitations. First, the association tests are prone to false-positive findings when differential measurement errors between cases and controls arise from differences in DNA quality or handling. Second, the uncertainties in the ASCN calls are ignored. We present a general framework for the integrated analysis of CNVs and SNPs, including the analysis of total copy numbers as a special case. Our approach combines the ASCN calling and the association analysis into a single step while allowing for differential measurement errors. We construct likelihood functions that properly account for case-control sampling and measurement errors. We establish the asymptotic properties of the maximum likelihood estimators and develop EM algorithms to implement the corresponding inference procedures. The advantages of the proposed methods over the existing ones are demonstrated through realistic simulation studies and an application to a genome-wide association study of schizophrenia. Extensions to next-generation sequencing data are discussed.
Dahabreh, Issa J; Trikalinos, Thomas A; Lau, Joseph; Schmid, Christopher H
2017-03-01
To compare statistical methods for meta-analysis of sensitivity and specificity of medical tests (e.g., diagnostic or screening tests). We constructed a database of PubMed-indexed meta-analyses of test performance from which 2 × 2 tables for each included study could be extracted. We reanalyzed the data using univariate and bivariate random effects models fit with inverse variance and maximum likelihood methods. Analyses were performed using both normal and binomial likelihoods to describe within-study variability. The bivariate model using the binomial likelihood was also fit using a fully Bayesian approach. We use two worked examples-thoracic computerized tomography to detect aortic injury and rapid prescreening of Papanicolaou smears to detect cytological abnormalities-to highlight that different meta-analysis approaches can produce different results. We also present results from reanalysis of 308 meta-analyses of sensitivity and specificity. Models using the normal approximation produced sensitivity and specificity estimates closer to 50% and smaller standard errors compared to models using the binomial likelihood; absolute differences of 5% or greater were observed in 12% and 5% of meta-analyses for sensitivity and specificity, respectively. Results from univariate and bivariate random effects models were similar, regardless of estimation method. Maximum likelihood and Bayesian methods produced almost identical summary estimates under the bivariate model; however, Bayesian analyses indicated greater uncertainty around those estimates. Bivariate models produced imprecise estimates of the between-study correlation of sensitivity and specificity. Differences between methods were larger with increasing proportion of studies that were small or required a continuity correction. The binomial likelihood should be used to model within-study variability. Univariate and bivariate models give similar estimates of the marginal distributions for sensitivity and specificity. Bayesian methods fully quantify uncertainty and their ability to incorporate external evidence may be useful for imprecisely estimated parameters. Copyright © 2017 Elsevier Inc. All rights reserved.
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.
Functional decline in the elderly with MCI: Cultural adaptation of the ADCS-ADL scale.
Cintra, Fabiana Carla Matos da Cunha; Cintra, Marco Túlio Gualberto; Nicolato, Rodrigo; Bertola, Laiss; Ávila, Rafaela Teixeira; Malloy-Diniz, Leandro Fernandes; Moraes, Edgar Nunes; Bicalho, Maria Aparecida Camargos
2017-07-01
Translate, transcultural adaptation and application to Brazilian Portuguese of the Alzheimer's Disease Cooperative Study - Activities of Daily Living (ADCS-ADL) scale as a cognitive screening instrument. We applied the back translation added with pretest and bilingual methods. The sample was composed by 95 elderly individuals and their caregivers. Thirty-two (32) participants were diagnosed as mild cognitive impairment (MCI) patients, 33 as Alzheimer's disease (AD) patients and 30 were considered as cognitively normal individuals. There were only little changes on the scale. The Cronbach alpha coefficient was 0.89. The scores were 72.9 for control group, followed by MCI (65.1) and by AD (55.9), with a p-value < 0.001. The ROC curve value was 0.89. We considered a cut point of 72 and we observed a sensibility of 86.2%, specificity of 70%, positive predictive value of 86.2%, negative predictive value of 70%, positive likelihood ratio of 2.9 and negative likelihood ratio of 0.2. ADCS-ADL scale presents satisfactory psychometric properties to discriminate between MCI, AD and normal cognition.
Prevalence of Abuse Among Young Children with Rib Fractures: A Systematic Review
Paine, Christine Weirich; Fakeye, Oludolapo; Christian, Cindy W.; Wood, Joanne N.
2016-01-01
Objectives We aimed to estimate the prevalence of abuse in young children presenting with rib fractures and to identify demographic, injury, and presentation-related characteristics that affect the probability that rib fractures are secondary to abuse. Methods We searched PubMed/MEDLINE and CINAHL databases for articles published in English between January 1, 1990 and June 30, 2014 on rib fracture etiology in children ≤ 5 years old. Two reviewers independently extracted predefined data elements and assigned quality ratings to included studies. Study-specific abuse prevalences and the sensitivities, specificities, and positive and negative likelihood ratios of patients’ demographic and clinical characteristics for abuse were calculated with 95% confidence intervals. Results Data for 1,396 children ≤ 48 months old with rib fractures were abstracted from 10 articles. Among infants < 12 months old, abuse prevalence ranged from 67% to 84%, whereas children 12-23 months old and 24-35 months old had study-specific abuse prevalences of 29% and 28% respectively. Age < 12 months was the only characteristic significantly associated with increased likelihood of abuse across multiple studies. Rib fracture location was not associated with likelihood of abuse. The retrospective design of the included studies and variations in ascertainment of cases, inclusion/exclusion criteria, and child abuse assessments prevented further meta-analysis. Conclusions Abuse is the most common cause of rib fractures in infants < 12 months old. Prospective studies with standardized methods are needed to improve accuracy in determining abuse prevalence among children with rib fractures and characteristics associated with abusive rib fractures. PMID:27749806
Wang, Liang; Xia, Yu; Jiang, Yu-Xin; Dai, Qing; Li, Xiao-Yi
2012-11-01
To assess the efficacy of sonography for discriminating nodular Hashimoto thyroiditis from papillary thyroid carcinoma in patients with sonographically evident diffuse Hashimoto thyroiditis. This study included 20 patients with 24 surgically confirmed Hashimoto thyroiditis nodules and 40 patients with 40 papillary thyroid carcinoma nodules; all had sonographically evident diffuse Hashimoto thyroiditis. A retrospective review of the sonograms was performed, and significant benign and malignant sonographic features were selected by univariate and multivariate analyses. The combined likelihood ratio was calculated as the product of each feature's likelihood ratio for papillary thyroid carcinoma. We compared the abilities of the original sonographic features and combined likelihood ratios in diagnosing nodular Hashimoto thyroiditis and papillary thyroid carcinoma by their sensitivity, specificity, and Youden index. The diagnostic capabilities of the sonographic features varied greatly, with Youden indices ranging from 0.175 to 0.700. Compared with single features, combinations of features were unable to improve the Youden indices effectively because the sensitivity and specificity usually changed in opposite directions. For combined likelihood ratios, however, the sensitivity improved greatly without an obvious reduction in specificity, which resulted in the maximum Youden index (0.825). With a combined likelihood ratio greater than 7.00 as the diagnostic criterion for papillary thyroid carcinoma, sensitivity reached 82.5%, whereas specificity remained at 100.0%. With a combined likelihood ratio less than 1.00 for nodular Hashimoto thyroiditis, sensitivity and specificity were 90.0% and 92.5%, respectively. Several sonographic features of nodular Hashimoto thyroiditis and papillary thyroid carcinoma in a background of diffuse Hashimoto thyroiditis were significantly different. The combined likelihood ratio may be superior to original sonographic features for discrimination of nodular Hashimoto thyroiditis from papillary thyroid carcinoma; therefore, it is a promising risk index for thyroid nodules and warrants further investigation.
Validation of a stroke symptom questionnaire for epidemiological surveys.
Abe, Ivana Makita; Goulart, Alessandra Carvalho; Santos Júnior, Waldyr Rodrigues; Lotufo, Paulo Andrade; Benseñor, Isabela Martins
2010-07-01
Stroke is a relevant issue within public health and requires epidemiological surveillance tools. The aim here was to validate a questionnaire for evaluating individuals with stroke symptoms in the Stroke Morbidity and Mortality Study (Estudo de Mortalidade e Morbidade do Acidente Vascular Cerebral, EMMA), São Paulo, Brazil. This was a cross-sectional study performed among a sample of the inhabitants of Butantã, an area in the western zone of the city of São Paulo. For all households in the coverage area of a primary healthcare unit, household members over the age of 35 years answered a stroke symptom questionnaire addressing limb weakness, facial weakness, speech problems, sensory disorders and impaired vision. Thirty-six participants were randomly selected for a complete neurological examination (gold standard). Considering all the questions in the questionnaire, the sensitivity was 72.2%, specificity was 94.4%, positive predictive value was 92.9% and negative predictive value was 77.3%. The positive likelihood ratio was 12.9, the negative likelihood ratio was 0.29 and the kappa coefficient was 0.67. Limb weakness was the most sensitive symptom, and speech problems were the most specific. The stroke symptom questionnaire is a useful tool and can be applied by trained interviewers with the aim of identifying community-dwelling stroke patients, through the structure of the Family Health Program.
Identifying Malignant Pleural Effusion by A Cancer Ratio (Serum LDH: Pleural Fluid ADA Ratio).
Verma, Akash; Abisheganaden, John; Light, R W
2016-02-01
We studied the diagnostic potential of serum lactate dehydrogenase (LDH) in malignant pleural effusion. Retrospective analysis of patients hospitalized with exudative pleural effusion in 2013. Serum LDH and serum LDH: pleural fluid ADA ratio was significantly higher in cancer patients presenting with exudative pleural effusion. In multivariate logistic regression analysis, pleural fluid ADA was negatively correlated 0.62 (0.45-0.85, p = 0.003) with malignancy, whereas serum LDH 1.02 (1.0-1.03, p = 0.004) and serum LDH: pleural fluid ADA ratio 0.94 (0.99-1.0, p = 0.04) was correlated positively with malignant pleural effusion. For serum LDH: pleural fluid ADA ratio, a cut-off level of >20 showed sensitivity, specificity of 0.98 (95 % CI 0.92-0.99) and 0.94 (95 % CI 0.83-0.98), respectively. The positive likelihood ratio was 32.6 (95 % CI 10.7-99.6), while the negative likelihood ratio at this cut-off was 0.03 (95 % CI 0.01-0.15). Higher serum LDH and serum LDH: pleural fluid ADA ratio in patients presenting with exudative pleural effusion can distinguish between malignant and non-malignant effusion on the first day of hospitalization. The cut-off level for serum LDH: pleural fluid ADA ratio of >20 is highly predictive of malignancy in patients with exudative pleural effusion (whether lymphocytic or neutrophilic) with high sensitivity and specificity.
The role of multisensory interplay in enabling temporal expectations.
Ball, Felix; Michels, Lara E; Thiele, Carsten; Noesselt, Toemme
2018-01-01
Temporal regularities can guide our attention to focus on a particular moment in time and to be especially vigilant just then. Previous research provided evidence for the influence of temporal expectation on perceptual processing in unisensory auditory, visual, and tactile contexts. However, in real life we are often exposed to a complex and continuous stream of multisensory events. Here we tested - in a series of experiments - whether temporal expectations can enhance perception in multisensory contexts and whether this enhancement differs from enhancements in unisensory contexts. Our discrimination paradigm contained near-threshold targets (subject-specific 75% discrimination accuracy) embedded in a sequence of distractors. The likelihood of target occurrence (early or late) was manipulated block-wise. Furthermore, we tested whether spatial and modality-specific target uncertainty (i.e. predictable vs. unpredictable target position or modality) would affect temporal expectation (TE) measured with perceptual sensitivity (d ' ) and response times (RT). In all our experiments, hidden temporal regularities improved performance for expected multisensory targets. Moreover, multisensory performance was unaffected by spatial and modality-specific uncertainty, whereas unisensory TE effects on d ' but not RT were modulated by spatial and modality-specific uncertainty. Additionally, the size of the temporal expectation effect, i.e. the increase in perceptual sensitivity and decrease of RT, scaled linearly with the likelihood of expected targets. Finally, temporal expectation effects were unaffected by varying target position within the stream. Together, our results strongly suggest that participants quickly adapt to novel temporal contexts, that they benefit from multisensory (relative to unisensory) stimulation and that multisensory benefits are maximal if the stimulus-driven uncertainty is highest. We propose that enhanced informational content (i.e. multisensory stimulation) enables the robust extraction of temporal regularities which in turn boost (uni-)sensory representations. Copyright © 2017 Elsevier B.V. All rights reserved.
ANA testing in the presence of acute and chronic infections.
Litwin, Christine M; Binder, Steven R
2016-01-01
Autoantibody testing is performed to help diagnose patients who have clinical symptoms suggestive of possible autoimmune diseases. Antinuclear antibodies (ANA) are present in many systemic autoimmune conditions such as systemic lupus erythematosus (SLE). However, a positive ANA test may also be seen with non-autoimmune inflammatory diseases, including both acute and chronic infections. When the ANA test is used as an initial screen in patients with non-specific clinical symptoms, such as fever, joint pain, myalgias, fatigue, rash, or anemia, the likelihood of a positive result due to infection will increase, especially in children. This article identifies acute and chronic infectious diseases that are likely to produce a positive ANA result and summarizes recent literature addressing both the causes and consequences of these findings.
Descatha, A; Dale, A-M; Franzblau, A; Coomes, J; Evanoff, B
2010-02-01
We evaluated the utility of physical examination manoeuvres in the prediction of carpal tunnel syndrome (CTS) in a population-based research study. We studied a cohort of 1108 newly employed workers in several industries. Each worker completed a symptom questionnaire, a structured physical examination and nerve conduction study. For each hand, our CTS case definition required both median nerve conduction abnormality and symptoms classified as "classic" or "probable" on a hand diagram. We calculated the positive predictive values and likelihood ratios for physical examination manoeuvres in subjects with and without symptoms. The prevalence of CTS in our cohort was 1.2% for the right hand and 1.0% for the left hand. The likelihood ratios of a positive test for physical provocative tests ranged from 2.0 to 3.3, and those of a negative test from 0.3 to 0.9. The post-test probability of positive testing was <50% for all strategies tested. Our study found that physical examination, alone or in combination with symptoms, was not predictive of CTS in a working population. We suggest using specific symptoms as a first-level screening tool, and nerve conduction study as a confirmatory test, as a case definition strategy in research settings.
Horton, Karissa D.; Loukas, Alexandra
2014-01-01
Depressive symptoms are associated with increased levels of cigarette smoking, yet not every individual experiencing depressive symptoms smokes. This study examined whether religious coping moderated the impact of depressive symptoms on past 30-day cigarette use among a racially/ethnically diverse sample of 963 post-secondary vocational students (46.8% women; mean age = 25 years). Results from negative binomial regression analyses indicated that depressive symptoms increased the likelihood of cigarette smoking (quantity-frequency measure of cigarette use) for female students, whereas positive religious coping decreased the likelihood of smoking for female students. Consistent with religious coping theory and as expected, negative religious coping moderated the depressive symptoms-smoking relationship such that negative religious coping exacerbated the impact of depressive symptoms on cigarette smoking among females. Positive religious coping also moderated the depressive symptoms-cigarette smoking relationship for females. However, contrary to expectations, high levels of positive religious coping exacerbated the likelihood of cigarette smoking among females with high levels of depressive symptoms. Surprisingly, neither depressive symptoms nor positive or negative religious coping contributed to the likelihood of males’ smoking. Study limitations and suggestions for directions in future research are discussed. PMID:23276324
2013-01-01
Background In emergency settings, verification of endotracheal tube (ETT) location is important for critically ill patients. Ignorance of oesophageal intubation can be disastrous. Many methods are used for verification of the endotracheal tube location; none are ideal. Quantitative waveform capnography is considered the standard of care for this purpose but is not always available and is expensive. Therefore, this feasibility study is conducted to compare a cheaper alternative, bedside upper airway ultrasonography to waveform capnography, for verification of endotracheal tube location after intubation. Methods This was a prospective, single-centre, observational study, conducted at the HRPB, Ipoh. It included patients who were intubated in the emergency department from 28 March 2012 to 17 August 2012. A waiver of consent had been obtained from the Medical Research Ethics Committee. Bedside upper airway ultrasonography was performed after intubation and compared to waveform capnography. Specificity, sensitivity, positive and negative predictive value and likelihood ratio are calculated. Results A sample of 107 patients were analysed, and 6 (5.6%) had oesophageal intubations. The overall accuracy of bedside upper airway ultrasonography was 98.1% (95% confidence interval (CI) 93.0% to 100.0%). The kappa value (Κ) was 0.85, indicating a very good agreement between the bedside upper airway ultrasonography and waveform capnography. Thus, bedside upper airway ultrasonography is in concordance with waveform capnography. The sensitivity, specificity, positive predictive value and negative predictive value of bedside upper airway ultrasonography were 98.0% (95% CI 93.0% to 99.8%), 100% (95% CI 54.1% to 100.0%), 100% (95% CI 96.3% to 100.0%) and 75.0% (95% CI 34.9% to 96.8%). The likelihood ratio of a positive test is infinite and the likelihood ratio of a negative test is 0.0198 (95% CI 0.005 to 0.0781). The mean confirmation time by ultrasound is 16.4 s. No adverse effects were recorded. Conclusions Our study shows that ultrasonography can replace waveform capnography in confirming ETT placement in centres without capnography. This can reduce incidence of unrecognised oesophageal intubation and prevent morbidity and mortality. Trial registration National Medical Research Register NMRR11100810230. PMID:23826756
Bhadoria, Ajeet Singh; Kasar, Pradeep Kumar; Toppo, Neelam Anupama
2015-01-01
Globally the increasing prevalence of diabetes mellitus (DM) is major public health concern. The Indian Diabetes Risk Score (IDRS) was developed by Madras Diabetes Research Foundation (MDRF) as a simple tool to help detect undiagnosed type 2 DM (T2DM) in the community. We conducted a study among 911 adults of Jabalpur District to validate the IDRS score against increased fasting blood sugar levels in diagnosing T2DM. T2DM was confirmed either by history of previously known disease or fasting plasma glucose ≥126 mg/dl on two occasions. Sensitivity, specificity, positive predictive value, negative predictive value, Youden index (sensitivity + specificity -1), likelihood ratio for positive test, and likelihood ratio for negative test were calculated for IDRS cut-offs of ≥20, ≥40, ≥60, and ≥80 against the presence of T2DM (either known diabetic or fasting plasma glucose >126 mg/dl on two occasions). The overall prevalence of T2DM was 9.99% (95% confidence interval, 8.04-11.94%). In the Receiver operating characteristic analysis, IDRS had an area under the curve of 0.736 (P < 0.001). The best cut-off was IDRS 40 with a sensitivity, specificity, and Youden index of 60.4%, 70.7%, and 0.31, respectively. The findings of our study indicate that IDRS has excellent predictive value for detecting undiagnosed diabetes in the community and IDRS is also a much stronger risk indicator than examining individual risk factors like age, family history, obesity, or physical activity.
Pacek, Lauren R; Rass, Olga; Johnson, Matthew W
2017-10-01
Smoking cessation has proven to be a challenge for HIV-positive smokers. Patient and provider characteristics may provide barriers to smoking cessation. We aimed to identify characteristics associated with interest in cessation as well as characterize use of, current interest in, and provider recommendations for smoking cessation modalities. Data came from 275 HIV-positive smokers recruited online. Half (49.1%) of the sample was interested in quitting; daily smoking was associated with decreased likelihood of interest in cessation, whereas making a lifetime quit attempt, receiving encouragement to quit from an HIV care provider, and greater frequency of discussions regarding cessation with HIV care providers were associated with increased likelihood of interest in cessation. Nicotine replacement therapy was the most commonly used (42.9%), generated the most interest (59.1%), and was the most commonly clinician-recommended (70.7%) cessation modality. Findings emphasize the importance of the healthcare provider-patient relationship for smoking cessation promotion in HIV-positive smokers.
Nadeau, Mélissa; Rosas-Arellano, M Patricia; Gurr, Kevin R; Bailey, Stewart I; Taylor, David C; Grewal, Ruby; Lawlor, D Kirk; Bailey, Chris S
2013-12-01
Intermittent claudication can be neurogenic or vascular. Physicians use a profile based on symptom attributes to differentiate the 2 types of claudication, and this guides their investigations for diagnosis of the underlying pathology. We evaluated the validity of these symptom attributes in differentiating neurogenic from vascular claudication. Patients with a diagnosis of lumbar spinal stenosis (LSS) or peripheral vascular disease (PVD) who reported claudication answered 14 questions characterizing their symptoms. We determined the sensitivity, specificity and positive and negative likelihood ratios (PLR and NLR) for neurogenic and vascular claudication for each symptom attribute. We studied 53 patients. The most sensitive symptom attribute to rule out LSS was the absence of "triggering of pain with standing alone" (sensitivity 0.97, NLR 0.050). Pain alleviators and symptom location data showed a weak clinical significance for LSS and PVD. Constellation of symptoms yielded the strongest associations: patients with a positive shopping cart sign whose symptoms were located above the knees, triggered with standing alone and relieved with sitting had a strong likelihood of neurogenic claudication (PLR 13). Patients with symptoms in the calf that were relieved with standing alone had a strong likelihood of vascular claudication (PLR 20.0). The classic symptom attributes used to differentiate neurogenic from vascular claudication are at best weakly valid independently. However, certain constellation of symptoms are much more indicative of etiology. These results can guide general practitioners in their evaluation of and investigation for claudication.
Hospital mergers and market overlap.
Brooks, G R; Jones, V G
1997-01-01
OBJECTIVE: To address two questions: What are the characteristics of hospitals that affect the likelihood of their being involved in a merger? What characteristics of particular pairs of hospitals affect the likelihood of the pair engaging in a merger? DATA SOURCES/STUDY SETTING: Hospitals in the 12 county region surrounding the San Francisco Bay during the period 1983 to 1992 were the focus of the study. Data were drawn from secondary sources, including the Lexis/Nexis database, the American Hospital Association, and the Office of Statewide Health Planning and Development of the State of California. STUDY DESIGN: Seventeen hospital mergers during the study period were identified. A random sample of pairs of hospitals that did not merge was drawn to establish a statistically efficient control set. Models constructed from hypotheses regarding hospital and market characteristics believed to be related to merger likelihood were tested using logistic regression analysis. DATA COLLECTION: See Data Sources/Study Setting. PRINCIPAL FINDINGS: The analysis shows that the likelihood of a merger between a particular pair of hospitals is positively related to the degree of market overlap that exists between them. Furthermore, market overlap and performance difference interact in their effect on merger likelihood. In an analysis of individual hospitals, conditions of rivalry, hospital market share, and hospital size were not found to influence the likelihood that a hospital will engage in a merger. CONCLUSIONS: Mergers between hospitals are not driven directly by considerations of market power or efficiency as much as by the existence of specific merger opportunities in the hospitals' local markets. Market overlap is a condition that enables a merger to occur, but other factors, such as the relative performance levels of the hospitals in question and their ownership and teaching status, also play a role in influencing the likelihood that a merger will in fact take place. PMID:9018212
Explaining the effect of event valence on unrealistic optimism.
Gold, Ron S; Brown, Mark G
2009-05-01
People typically exhibit 'unrealistic optimism' (UO): they believe they have a lower chance of experiencing negative events and a higher chance of experiencing positive events than does the average person. UO has been found to be greater for negative than positive events. This 'valence effect' has been explained in terms of motivational processes. An alternative explanation is provided by the 'numerosity model', which views the valence effect simply as a by-product of a tendency for likelihood estimates pertaining to the average member of a group to increase with the size of the group. Predictions made by the numerosity model were tested in two studies. In each, UO for a single event was assessed. In Study 1 (n = 115 students), valence was manipulated by framing the event either negatively or positively, and participants estimated their own likelihood and that of the average student at their university. In Study 2 (n = 139 students), valence was again manipulated and participants again estimated their own likelihood; additionally, group size was manipulated by having participants estimate the likelihood of the average student in a small, medium-sized, or large group. In each study, the valence effect was found, but was due to an effect on estimates of own likelihood, not the average person's likelihood. In Study 2, valence did not interact with group size. The findings contradict the numerosity model, but are in accord with the motivational explanation. Implications for health education are discussed.
Han, Jin H.; Wilson, Amanda; Graves, Amy J.; Shintani, Ayumi; Schnelle, John F.; Dittus, Robert S.; Powers, James S.; Vernon, John; Storrow, Alan B.; Ely, E. Wesley
2014-01-01
Objectives In the emergency department (ED), health care providers miss delirium approximately 75% of the time, because they do not routinely screen for this syndrome. The Confusion Assessment Method for the Intensive Care Unit (CAM-ICU) is a brief (<1 minute) delirium assessment that may be feasible for use in the ED. The study objective was to determine its validity and reliability in older ED patients. Methods In this prospective observational cohort study, patients aged 65 years or older were enrolled at an academic, tertiary care ED from July 2009 to February 2012. Research assistants (RAs) and an emergency physician (EP) performed the CAM-ICU. The reference standard for delirium was a comprehensive (~30 minutes) psychiatrist assessment using the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision criteria. All assessments were blinded to each other and were conducted within 3 hours. Sensitivities, specificities, and likelihood ratios were calculated for both the EP and the RAs using the psychiatrist’s assessment as the reference standard. Kappa values between the EP and RAs were also calculated to measure reliability. Results Of 406 patients enrolled, 50 (12.3%) had delirium. The median age was 73.5 years old (interquartile range [IQR] = 69 to 80 years), 202 (49.8%) were female, and 57 (14.0%) were nonwhite. The CAM-ICU’s sensitivities were 72.0% (95% confidence interval [CI] = 58.3% to 82.5%) and 68.0% (95% CI = 54.2% to 79.2%) in the EP and RAs, respectively. The CAM-ICU’s specificity was 98.6% (95% CI = 96.8% to 99.4%) for both raters. The negative likelihood ratios (LR–) were 0.28 (95% CI = 0.18 to 0.44) and 0.32 (95% CI = 0.22 to 0.49) in the EP and RAs, respectively. The positive likelihood ratios (LR+) were 51.3 (95% CI = 21.1 to 124.5) and 48.4 (95% CI = 19.9 to 118.0), respectively. The kappa between the EP and RAs was 0.92 (95% CI = 0.85 to 0.98), indicating excellent interobserver reliability. Conclusions In older ED patients, the CAM-ICU is highly specific, and a positive test is nearly diagnostic for delirium when used by both RAs and EPs. However, the CAM-ICU’s sensitivity was modest, and a negative test decreased the likelihood of delirium by a small amount. The consequences of a false-negative CAM-ICU are unknown and deserve further study. PMID:24673674
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
Babafemi, Emmanuel O; Cherian, Benny P; Banting, Lee; Mills, Graham A; Ngianga, Kandala
2017-10-25
Rapid and accurate diagnosis of tuberculosis (TB) is key to manage the disease and to control and prevent its transmission. Many established diagnostic methods suffer from low sensitivity or delay of timely results and are inadequate for rapid detection of Mycobacterium tuberculosis (MTB) in pulmonary and extra-pulmonary clinical samples. This study examined whether a real-time polymerase chain reaction (RT-PCR) assay, with a turn-a-round time of 2 h, would prove effective for routine detection of MTB by clinical microbiology laboratories. A systematic literature search was performed for publications in any language on the detection of MTB in pathological samples by RT-PCR assay. The following sources were used MEDLINE via PubMed, EMBASE, BIOSIS Citation Index, Web of Science, SCOPUS, ISI Web of Knowledge and Cochrane Infectious Diseases Group Specialised Register, grey literature, World Health Organization and Centres for Disease Control and Prevention websites. Forty-six studies met set inclusion criteria. Generated pooled summary estimates (95% CIs) were calculated for overall accuracy and bivariate meta-regression model was used for meta-analysis. Summary estimates for pulmonary TB (31 studies) were as follows: sensitivity 0.82 (95% CI 0.81-0.83), specificity 0.99 (95% CI 0.99-0.99), positive likelihood ratio 43.00 (28.23-64.81), negative likelihood ratio 0.16 (0.12-0.20), diagnostic odds ratio 324.26 (95% CI 189.08-556.09) and area under curve 0.99. Summary estimates for extra-pulmonary TB (25 studies) were as follows: sensitivity 0.70 (95% CI 0.67-0.72), specificity 0.99 (95% CI 0.99-0.99), positive likelihood ratio 29.82 (17.86-49.78), negative likelihood ratio 0.33 (0.26-0.42), diagnostic odds ratio 125.20 (95% CI 65.75-238.36) and area under curve 0.96. RT-PCR assay demonstrated a high degree of sensitivity for pulmonary TB and good sensitivity for extra-pulmonary TB. It indicated a high degree of specificity for ruling in TB infection from sampling regimes. This was acceptable, but may better as a rule out add-on diagnostic test. RT-PCR assays demonstrate both a high degree of sensitivity in pulmonary samples and rapidity of detection of TB which is an important factor in achieving effective global control and for patient management in terms of initiating early and appropriate anti-tubercular therapy. PROSPERO CRD42015027534 .
Control/display trade-off study for single-pilot instrument flight rule operations
NASA Technical Reports Server (NTRS)
Hoh, R.
1983-01-01
The objectives were to determine minimum autopilot functions and displays required to keep pilot workload at an acceptable level; to determine what constitutes an acceptable level of workload; to identify critical tasks; and to suggest specific experiments required to refine conclusions. It was determined that workload relief is derived from basic stability augmentation; that complex autopilots can lead to serious blunders; and that displays need to enhance positional awareness and minimize the likelihood of false hypothesis.
Monte Carlo-based Reconstruction in Water Cherenkov Detectors using Chroma
NASA Astrophysics Data System (ADS)
Seibert, Stanley; Latorre, Anthony
2012-03-01
We demonstrate the feasibility of event reconstruction---including position, direction, energy and particle identification---in water Cherenkov detectors with a purely Monte Carlo-based method. Using a fast optical Monte Carlo package we have written, called Chroma, in combination with several variance reduction techniques, we can estimate the value of a likelihood function for an arbitrary event hypothesis. The likelihood can then be maximized over the parameter space of interest using a form of gradient descent designed for stochastic functions. Although slower than more traditional reconstruction algorithms, this completely Monte Carlo-based technique is universal and can be applied to a detector of any size or shape, which is a major advantage during the design phase of an experiment. As a specific example, we focus on reconstruction results from a simulation of the 200 kiloton water Cherenkov far detector option for LBNE.
Shi, Jia-Xin; Li, Jia-Shu; Hu, Rong; Li, Chun-Hua; Wen, Yan; Zheng, Hong; Zhang, Feng; Li, Qin
2013-01-01
The serum soluble triggering receptor expressed on myeloid cells-1 (sTREM-1) is a useful biomarker in differentiating bacterial infections from others. However, the diagnostic value of sTREM-1 in bronchoalveolar lavage fluid (BALF) in lung infections has not been well established. We performed a meta-analysis to assess the accuracy of sTREM-1 in BALF for diagnosis of bacterial lung infections in intensive care unit (ICU) patients. We searched PUBMED, EMBASE and Web of Knowledge (from January 1966 to October 2012) databases for relevant studies that reported diagnostic accuracy data of BALF sTREM-1 in the diagnosis of bacterial lung infections in ICU patients. Pooled sensitivity, specificity, and positive and negative likelihood ratios were calculated by a bivariate regression analysis. Measures of accuracy and Q point value (Q*) were calculated using summary receiver operating characteristic (SROC) curve. The potential between-studies heterogeneity was explored by subgroup analysis. Nine studies were included in the present meta-analysis. Overall, the prevalence was 50.6%; the sensitivity was 0.87 (95% confidence interval (CI), 0.72-0.95); the specificity was 0.79 (95% CI, 0.56-0.92); the positive likelihood ratio (PLR) was 4.18 (95% CI, 1.78-9.86); the negative likelihood ratio (NLR) was 0.16 (95% CI, 0.07-0.36), and the diagnostic odds ratio (DOR) was 25.60 (95% CI, 7.28-89.93). The area under the SROC curve was 0.91 (95% CI, 0.88-0.93), with a Q* of 0.83. Subgroup analysis showed that the assay method and cutoff value influenced the diagnostic accuracy of sTREM-1. BALF sTREM-1 is a useful biomarker of bacterial lung infections in ICU patients. Further studies are needed to confirm the optimized cutoff value.
Validation of the portable Air-Smart Spirometer
Núñez Fernández, Marta; Pallares Sanmartín, Abel; Mouronte Roibas, Cecilia; Cerdeira Domínguez, Luz; Botana Rial, Maria Isabel; Blanco Cid, Nagore; Fernández Villar, Alberto
2018-01-01
Background The Air-Smart Spirometer is the first portable device accepted by the European Community (EC) that performs spirometric measurements by a turbine mechanism and displays the results on a smartphone or a tablet. Methods In this multicenter, descriptive and cross-sectional prospective study carried out in 2 hospital centers, we compare FEV1, FVC, FEV1/FVC ratio measured with the Air Smart-Spirometer device and a conventional spirometer, and analyze the ability of this new portable device to detect obstructions. Patients were included for 2 consecutive months. We calculate sensitivity, specificity, positive and negative predictive value (PPV and NPV) and likelihood ratio (LR +, LR-) as well as the Kappa Index to evaluate the concordance between the two devices for the detection of obstruction. The agreement and relation between the values of FEV1 and FVC in absolute value and the FEV1/FVC ratio measured by both devices were analyzed by calculating the intraclass correlation coefficient (ICC) and the Pearson correlation coefficient (r) respectively. Results 200 patients (100 from each center) were included with a mean age of 57 (± 14) years, 110 were men (55%). Obstruction was detected by conventional spirometry in 73 patients (40.1%). Using a FEV1/FVC ratio smaller than 0.7 to detect obstruction with the Air Smart-Spirometer, the kappa index was 0.88, sensitivity (90.4%), specificity (97.2%), PPV (95.7%), NPV (93.7%), positive likelihood ratio (32.29), and negative likelihood ratio (0.10). The ICC and r between FEV1, FVC, and FEV1 / FVC ratio measured by the Air Smart Spirometer and the conventional spirometer were all higher than 0.94. Conclusion The Air-Smart Spirometer is a simple and very precise instrument for detecting obstructive airway diseases. It is easy to use, which could make it especially useful non-specialized care and in other areas. PMID:29474502
Colder, Craig R; O'Connor, Roisin M; Read, Jennifer P; Eiden, Rina D; Lengua, Liliana J; Hawk, Larry W; Wieczorek, William F
2014-09-01
This longitudinal study provided a comprehensive examination of age-related changes in alcohol outcome expectancies, subjective evaluation of alcohol outcomes, and automatic alcohol associations in early adolescence. A community sample (52% female, 75% White/non-Hispanic) was assessed annually for 3 years (mean age at the first assessment = 11.6 years). Results from growth modeling suggested that perceived likelihood of positive outcomes increased and that subjective evaluations of these outcomes were more positive with age. Perceived likelihood of negative outcomes declined with age. Automatic alcohol associations were assessed with an Implicit Association Task (IAT), and were predominantly negative, but these negative associations weakened with age. High initial levels of perceived likelihood of positive outcomes at age 11 were associated with escalation of drinking. Perceived likelihood of negative outcomes was associated with low risk for drinking at age 11, but not with changes in drinking. Increases in positive evaluations of positive outcomes were associated with increases in alcohol use. Overall, findings suggest that at age 11, youth maintain largely negative attitudes and perceptions about alcohol, but with the transition into adolescence, there is a shift toward a more neutral or ambivalent view of alcohol. Some features of this shift are associated with escalation of drinking. Our findings point to the importance of delineating multiple aspects of alcohol information processing for extending cognitive models of alcohol use to the early stages of drinking.
Jing, Helen G.; Madore, Kevin P.; Schacter, Daniel L.
2015-01-01
Previous research has demonstrated that an episodic specificity induction – brief training in recollecting details of a recent experience – enhances performance on various subsequent tasks thought to draw upon episodic memory processes. Existing work has also shown that mental simulation can be beneficial for emotion regulation and coping with stressors. Here we focus on understanding how episodic detail can affect problem solving, reappraisal, and psychological well-being regarding worrisome future events. In Experiment 1, an episodic specificity induction significantly improved participants’ performance on a subsequent means-end problem solving task (i.e., more relevant steps) and an episodic reappraisal task (i.e., more episodic details) involving personally worrisome future events compared with a control induction not focused on episodic specificity. Imagining constructive behaviors with increased episodic detail via the specificity induction was also related to significantly larger decreases in anxiety, perceived likelihood of a bad outcome, and perceived difficulty to cope with a bad outcome, as well as larger increases in perceived likelihood of a good outcome and indicated use of active coping behaviors compared with the control. In Experiment 2, we extended these findings using a more stringent control induction, and found preliminary evidence that the specificity induction was related to an increase in positive affect and decrease in negative affect compared with the control. Our findings support the idea that episodic memory processes are involved in means-end problem solving and episodic reappraisal, and that increasing the episodic specificity of imagining constructive behaviors regarding worrisome events may be related to improved psychological well-being. PMID:26820166
Pepsin in saliva for the diagnosis of gastro-oesophageal reflux disease.
Hayat, Jamal O; Gabieta-Somnez, Shirley; Yazaki, Etsuro; Kang, Jin-Yong; Woodcock, Andrew; Dettmar, Peter; Mabary, Jerry; Knowles, Charles H; Sifrim, Daniel
2015-03-01
Current diagnostic methods for gastro-oesophageal reflux disease (GORD) have moderate sensitivity/specificity and can be invasive and expensive. Pepsin detection in saliva has been proposed as an 'office-based' method for GORD diagnosis. The aims of this study were to establish normal values of salivary pepsin in healthy asymptomatic subjects and to determine its value to discriminate patients with reflux-related symptoms (GORD, hypersensitive oesophagus (HO)) from functional heartburn (FH). 100 asymptomatic controls and 111 patients with heartburn underwent MII-pH monitoring and simultaneous salivary pepsin determination on waking, after lunch and dinner. Cut-off value for pepsin positivity was 16 ng/mL. Patients were divided into GORD (increased acid exposure time (AET), n=58); HO (normal AET and + Symptom Association Probability (SAP), n=26) and FH (normal AET and-SAP, n=27). 1/3 of asymptomatic subjects had pepsin in saliva at low concentration (0(0-59)ng/mL). Patients with GORD and HO had higher prevalence and pepsin concentration than controls (HO, 237(52-311)ng/mL and GORD, 121(29-252)ng/mL)(p<0.05). Patients with FH had low prevalence and concentration of pepsin in saliva (0(0-40) ng/mL). A positive test had 78.6% sensitivity and 64.9% specificity for diagnosis of GORD+HO (likelihood ratio: 2.23). However, one positive sample with >210 ng/mL pepsin suggested presence of GORD+HO with 98.2% specificity (likelihood ratio: 25.1). Only 18/84 (21.4%) of GORD+HO patients had 3 negative samples. In patients with symptoms suggestive of GORD, salivary pepsin testing may complement questionnaires to assist office-based diagnosis. This may lessen the use of unnecessary antireflux therapy and the need for further invasive and expensive diagnostic methods. 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.
Alvarez-Cuesta, E; Madrigal-Burgaleta, R; Angel-Pereira, D; Ureña-Tavera, A; Zamora-Verduga, M; Lopez-Gonzalez, P; Berges-Gimeno, M P
2015-07-01
Evidence regarding drug provocation test (DPT) with antineoplastic and biological agents is scarce. Our aim was to assess the usefulness of including DPT as a paramount gold standard diagnostic tool (prior to desensitization). Prospective, observational, longitudinal study with patients who, during a 3-year period, were referred to the Desensitization Program at Ramon y Cajal University Hospital. Patients underwent a structured diagnostic protocol by means of anamnesis, skin tests (ST), risk assessment, and DPT. Oxaliplatin-specific IgE was determined in oxaliplatin-reactive patients (who underwent DPT regardless of oxaliplatin-specific IgE results). Univariate analysis and multivariate analysis were used to identify predictors of the final diagnosis among several variables. A total of 186 patients were assessed. A total of 104 (56%) patients underwent DPT. Sixty-four percent of all DPTs were negative (i.e., hypersensitivity was excluded). Sensitivity for oxaliplatin-specific IgE (0.35 UI/l cutoff point) was 34%, specificity 90.3%, negative predictive value 45.9%, positive predictive value 85%, negative likelihood ratio 0.7, and positive likelihood ratio 3.5. These are the first reported data based on more than 100 DPTs with antineoplastic and biological agents (paclitaxel, oxaliplatin, rituximab, infliximab, irinotecan, and other drugs). Implementation of DPT in diagnostic protocols helps exclude hypersensitivity (in 36% of all referred patients), and avoids unnecessary desensitizations in nonhypersensitive patients (30-56% of patients, depending on culprit-drug). Drug provocation test is vital to validate diagnostic tools; consequently, quality data are shown on oxaliplatin-specific IgE and oxaliplatin-ST in the largest series of oxaliplatin-reactive patients reported to date (74 oxaliplatin-reactive patients). Identifying phenotypes and predictors of a diagnosis of hypersensitivity may be helpful for tailored plans. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Dusing, Reginald W.; Peng, Warner; Lai, Sue-Min; Grado, Gordon L.; Holzbeierlein, Jeffrey M.; Thrasher, J. Brantley; Hill, Jacqueline; Van Veldhuizen, Peter J.
2014-01-01
Purpose The aim of this study was to identify which patient characteristics are associated with the highest likelihood of positive findings on 11C-acetate PET/computed tomography attenuation correction (CTAC) (PET/CTAC) scan when imaging for recurrent prostate cancer. Methods From 2007 to 2011, 250 11C-acetate PET/CTAC scans were performed at a single institution on patients with prostate cancer recurrence after surgery, brachytherapy, or external beam radiation. Of these patients, 120 met our inclusion criteria. Logistic regression analysis was used to examine the relationship between predictability of positive findings and patients’ characteristics, such as prostate-specific antigen (PSA) level at the time of scan, PSA kinetics, Gleason score, staging, and type of treatment before scan. Results In total, 68.3% of the 120 11C-acetate PET/CTAC scans were positive. The percentage of positive scans and PSA at the time of scanning and PSA velocity (PSAV) had positive correlations. The putative sensitivity and specificity were 86.6% and 65.8%, respectively, when a PSA level greater than 1.24 ng/mL was used as the threshold for scanning. The putative sensitivity and specificity were 74% and 75%, respectively, when a PSAV level greater than 1.32 ng/mL/y was used as the threshold. No significant associations were found between scan positivity and age, PSA doubling time, Gleason score, staging, or type of treatment before scanning. Conclusions This retrospective study suggests that threshold models of PSA greater than 1.24 ng/mL or PSAV greater than 1.32 ng/mL per year are independent predictors of positive findings in 11C-acetate PET/CTAC imaging of recurrent prostate cancer. PMID:25036021
Urine Concentration and Pyuria for Identifying UTI in Infants.
Chaudhari, Pradip P; Monuteaux, Michael C; Bachur, Richard G
2016-11-01
Varying urine white blood cell (WBC) thresholds have been recommended for the presumptive diagnosis of urinary tract infection (UTI) among young infants. These thresholds have not been studied with newer automated urinalysis systems that analyze uncentrifuged urine that might be influenced by urine concentration. Our objective was to determine the optimal urine WBC threshold for UTI in young infants by using an automated urinalysis system, stratified by urine concentration. Retrospective cross-sectional study of infants aged <3 months evaluated for UTI in the emergency department with paired urinalysis and urine culture. UTI was defined as ≥50 000 colony-forming units/mL from catheterized specimens. Test characteristics were calculated across a range of WBC and leukocyte esterase (LE) cut-points, dichotomized into specific gravity groups (dilute <1.015; concentrated ≥1.015). Twenty-seven thousand infants with a median age of 1.7 months were studied. UTI prevalence was 7.8%. Optimal WBC cut-points were 3 WBC/high-power field (HPF) in dilute urine (likelihood ratio positive [LR+] 9.9, likelihood ratio negative [LR‒] 0.15) and 6 WBC/HPF (LR+ 10.1, LR‒ 0.17) in concentrated urine. For dipstick analysis, positive LE has excellent test characteristics regardless of urine concentration (LR+ 22.1, LR‒ 0.12 in dilute urine; LR+ 31.6, LR‒ 0.22 in concentrated urine). Urine concentration should be incorporated into the interpretation of automated microscopic urinalysis in young infants. Pyuria thresholds of 3 WBC/HPF in dilute urine and 6 WBC/HPF in concentrated urine are recommended for the presumptive diagnosis of UTI. Without correction of specific gravity, positive LE by automated dipstick is a reliably strong indicator of UTI. Copyright © 2016 by the American Academy of Pediatrics.
[Usefulness of sputum Gram staining in community-acquired pneumonia].
Sato, Tadashi; Aoshima, Masahiro; Ohmagari, Norio; Tada, Hiroshi; Chohnabayashi, Naohiko
2002-07-01
To evaluate the usefulness of sputum gram staining in community-acquired pneumonia (CAP), we reviewed 144 cases requiring hospitalization in the last 4 years. The sensitivity was 75.5%, specificity 68.2%, positive predictive value 74.1%, negative predictive value 69.8%, positive likelihood ratio 2.37, negative likelihood ratio 0.36 and accuracy 72.2% in 97 cases. Both sputum gram staining and culture were performed. Concerning bacterial pneumonia (65 cases), we compared the Gram staining group (n = 33), which received initial antibiotic treatment, based on sputum gram staining with the Empiric group (n = 32) that received antibiotics empirically. The success rates of the initial antibiotic treatment were 87.9% vs. 78.1% (P = 0.473); mean hospitalization periods were 9.67 vs. 11.75 days (P = 0.053); and periods of intravenous therapy were 6.73 vs. 7.91 days (P = 0.044), respectively. As for initial treatment, penicillins were used in the Gram staining group more frequently (P < 0.01). We conclude that sputum gram staining is useful for the shortening of the treatment period and the appropriate selection of initial antibiotics in bacterial pneumonia. We believe, therefore, that sputum gram staining is indispensable as a diagnostic tool CAP.
Variations in microbicide gel acceptability among young women in the USA and Puerto Rico
Giguere, Rebecca; Carballo-Diéguez, Alex; Ventuneac, Ana; Mabragaña, Marina; Dolezal, Curtis; Chen, Beatrice A.; Kahn, Jessica A.; Zimet, Gregory D.; McGowan, Ian
2011-01-01
In a multi-site study of vaginal microbicide acceptability conducted with sexually active young women, quantitative assessments revealed significant differences in acceptability by site. Participants in Puerto Rico rated the gel more favourably than mainland US participants in terms of liking the gel and likelihood of future use. To explain these differences, we examined responses to qualitative behavioural assessments. Young women in the mainland USA associated gel leakage with uncomfortable sensations experienced during menstruation, while young women in Puerto Rico had positive associations of gel use with douching. These negative or positive associations affected assessments of the gel’s physical qualities. In addition, young women’s perceptions of primary partners’ support for microbicide use influenced sexual satisfaction with the gel and, ultimately, product acceptability. Finally, geographic HIV risk context contributed to heightened HIV risk perception, which influenced likelihood of future microbicide use, even for women in stated monogamous relationships. Future microbicide acceptability studies should take into account potential differences in acceptability by site such as HIV risk perception based on local HIV prevalence, popularity of vaginal hygiene products in a specific area, and male attitudes in different cultures concerning women’s use of HIV protection strategies. PMID:22084840
Two-question depression-screeners - the solution to all problems?
Albani, Cornelia; Bailer, Harald; Blaser, Gerd; Brähler, Elmar; Geyer, Michael; Grulke, Norbert
2006-04-01
Depression constitutes a considerable issue in medicine and it is anticipated that the amount of people suffering from affective disorders will increase significantly. It would be useful to have a simple, fast screening procedure which would help detect depression. In four recently published articles a two-question depression-screener is recommended. Sensitivity, specificity, likelihood ratios, negative and positive predictive values were compared. For four different clinical samples and one sample that was representative of the German population the prevalence for depression ranged from 6.9 % to 18.1 %. Sensitivity and specificity reached values from 72.6 % to 96.6 % and from 56.9 % to 90.0 % respectively. All negative predictive values were high (< 97 %) opposed to positive predictive values (17.8 % to 38.5 %). Overall, it seems that the two-question screenings are well suited for the exclusion of a major depression. It is possible that regular screening could further lower the percentage of undiagnosed cases.
Fitzsimmons-Craft, Ellen E; Accurso, Erin C; Ciao, Anna C; Crosby, Ross D; Cao, Li; Pisetsky, Emily M; Le Grange, Daniel; Peterson, Carol B; Crow, Scott J; Engel, Scott G; Mitchell, James E; Wonderlich, Stephen A
2015-11-01
This study examined negative and positive affect in relation to restrictive eating episodes (i.e., meals/snacks perceived as restrictive) and whether restrictive eating was associated with likelihood of subsequent eating disorder behaviors (i.e., additional restrictive eating, binge eating, vomiting, laxative use, weighing, exercising, meal skipping, drinking fluids to curb appetite, body checking). Women with anorexia nervosa (N = 118) completed a 2-week ecological momentary assessment protocol. For both restrictive and nonrestrictive eating, negative affect significantly increased from prebehavior to the time of the behavior but remained stable thereafter, while positive affect remained stable from prebehavior to the time of the behavior but decreased significantly thereafter. Across time, negative affect was significantly lower and positive affect was significantly greater in restrictive than nonrestrictive episodes. Engagement in restrictive eating was associated with an increased likelihood of subsequent restrictive eating, laxative use, and body checking, but not other behaviors. Engagement in nonrestrictive eating was associated with a decreased likelihood of subsequent restrictive eating, binge eating, vomiting, laxative use, weighing, meal skipping, drinking fluids to curb appetite, and body checking. Despite similar patterns of affect across eating episodes over time, results suggest affect may be involved in the maintenance of restrictive eating in anorexia nervosa since restrictive episodes were associated with lower negative and greater positive affect across time compared to nonrestrictive episodes. Further, while restrictive episodes increased the likelihood of only three subsequent eating disorder behaviors, nonrestrictive episodes were protective since they decreased likelihood of all but one behavior. © 2015 Wiley Periodicals, Inc.
He, Y; Zhang, W; Huang, T; Wang, X; Wang, M
2015-10-01
To evaluate a diagnostic flow chart applying medical thoracoscoy (MT), adenosine deaminase (ADA) and T-SPOT.TB in diagnosis of tuberculous pleural effusion (TPE) at a high TB burden country. 136 patients with pleural effusion (PE) were enrolled and divided into TPE and Non-TPE group. MT (histology), PE ADA and T-SPOT.TB were conducted on all patients. ROC analysis was performed for the best cut-off value of PE ADA in detection of TPE. The diagnostic flow chart applying MT, ADA and T-SPOT.TB was evaluated for improving the limitations of each diagnostic method. ROC analysis showed that the best cut-off value of PE ADA was 30U/L. The sensitivity and specificity of these tests were calculated respectively to be: 71.4% (58.5%-81.6%) and 100% (95.4-100.0%) for MT, 92.9% (83.0-97.2%) and 68.8% (57.9-77.9%) for T-SPOT.TB, and 80.0% (69.6-88.1%) and 92.9% (82.7-98.0%) for PE ADA. The sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, positive predictive value and negative predictive value of the diagnostic flow chart were 96.4% (87.9-99.0%), 96.3% (89.6-98.7%), 25.714, 0.037, 97.4 and 94.9, respectively. The diagnostic flow chart applying MT, ADA and T-SPOT.TB is an accurate and rapid diagnostic method in detection of TPE.
Teixeira, João L G; Rabaioli, Paola; Savaris, Ricardo F
2015-01-01
To evaluate the performance of a commercial urinary test to screen for abnormal first trimester pregnancies in women presenting to an emergency room. In this prospective observational cohort, women with a confirmed first trimester pregnancy (gestational age <12 weeks) provided a urine sample for diagnosing the viability of their gestation. Pregnancy viability and location testing were confirmed by ultrasound and/or laparoscopy. From 815 eligible patients for the study, 12 were excluded for not having a confirmed pregnancy (n = 6) or were lost to follow-up (n = 6). A total of 803 patients underwent testing and completed follow-up. The pretest probability of an abnormal pregnancy was 44% (9% for ectopic pregnancy and 35% for miscarriage). The test had the following parameters to identify an abnormal first-trimester pregnancy (sensitivity, 13%; 95% confidence interval [CI], 10-17; specificity, 82%; 95% CI, 78-86; positive predictive value, 36; 95% CI, 28-46; negative predictive value, 54; 95% CI, 50-58; accuracy, 47%; positive likelihood ratio, 0.74; 95% CI, 0.53-1.03; negative likelihood ratio, 1.06; 95% CI, 1-1.12). The reproducibility of the test in our study was high (kappa index between readers, 0.89; 95% CI, 0.77-1). In our emergency setting, we were not able to confirm that the commercial test is adequate to detect or exclude an abnormal first-trimester pregnancy. Copyright © 2015 Elsevier Inc. All rights reserved.
The Incidence of Propionibacterium acnes in Open Shoulder Surgery: A Controlled Diagnostic Study.
Mook, William R; Klement, Mitchell R; Green, Cynthia L; Hazen, Kevin C; Garrigues, Grant E
2015-06-17
Propionibacterium acnes has arisen as the most common microorganism identified at the time of revision shoulder arthroplasty. There is limited evidence to suggest how frequently false-positive cultures occur. The purpose of this prospective controlled study was to evaluate culture growth from specimens obtained during open shoulder surgery. Patients undergoing an open deltopectoral approach to the shoulder were prospectively enrolled. Patients with a history of shoulder surgery or any concern for active or previous shoulder infection were excluded. Three pericapsular soft-tissue samples were taken from the shoulder for bacterial culture and were incubated for fourteen days. A sterile sponge was also analyzed in parallel with the tissue cultures. In addition, similar cultures were obtained from patients who had undergone previous shoulder surgery. Overall, 20.5% of surgeries (twenty-four of 117) yielded at least one specimen removed for culture that was positive for bacterial growth, and 13.0% of sterile control specimens (seven of fifty-four) had positive culture growth (p = 0.234). P. acnes represented 83.0% of all positive cultures (thirty-nine of forty-seven) at a median incubation time of fourteen days. Among the subjects who had not undergone previous surgery, 17.1% (fourteen of eighty-two) had at least one positive P. acnes culture. Male sex was univariably associated with a greater likelihood of bacterial growth (p < 0.01), and patients who had not undergone previous surgery and had received two or more preoperative corticosteroid injections had a higher likelihood of bacterial growth (p = 0.047). The clinical importance of positive P. acnes cultures from specimens obtained from open shoulder surgery remains uncertain. Male sex and preoperative corticosteroid injections were associated with a higher likelihood of bacterial growth on culture and are risk factors that merit further investigation. Previously reported incidences of positive P. acnes culture results from specimens from primary and revision shoulder arthroplasty may be overestimated because of a substantial level of culture contamination. P. acnes is isolated via culture at a substantial rate from shoulders undergoing a deltopectoral approach. The clinical importance of culture growth by this low-virulence organism still remains uncertain. Further study is necessary to more specifically characterize culture growth by P. acnes as an infection, commensal presence, or contaminant. Copyright © 2015 by The Journal of Bone and Joint Surgery, Incorporated.
Evangelista, Laura; Panunzio, Annalori; Polverosi, Roberta; Pomerri, Fabio; Rubello, Domenico
2014-03-01
The purpose of this study was to determine likelihood of malignancy for indeterminate lung nodules identified on CT comparing two standardized models with (18)F-FDG PET/CT. Fifty-nine cancer patients with indeterminate lung nodules (solid tumors; diameter, ≥5 mm) on CT had FDG PET/CT for lesion characterization. Mayo Clinic and Veterans Affairs Cooperative Study models of likelihood of malignancy were applied to solitary pulmonary nodules. High probability of malignancy was assigned a priori for multiple nodules. Low (<5%), intermediate (5-60%), and high (>60%) pretest malignancy probabilities were analyzed separately. Patients were reclassified with PET/CT. Histopathology or 2-year imaging follow-up established diagnosis. Outcome-based reclassification differences were defined as net reclassification improvement. A null hypothesis of asymptotic test was applied. Thirty-one patients had histology-proven malignancy. PET/CT was true-positive in 24 and true-negative in 25 cases. Negative predictive value was 78% and positive predictive value was 89%. On the basis of the Mayo Clinic model (n=31), 18 patients had low, 12 had intermediate, and one had high pretest likelihood; on the basis of the Veterans Affairs model (n=26), 5 patients had low, 20 had intermediate, and one had high pretest likelihood. Because of multiple lung nodules, 28 patients were classified as having high malignancy risk. PET/CT showed 32 negative and 27 positive scans. Net reclassification improvements respectively were 0.95 and 1.6 for Mayo Clinic and Veterans Affairs models (both p<0.0001). Fourteen of 31 (45.2%) and 12 of 26 (46.2%) patients with low and intermediate pretest likelihood, respectively, had positive findings on PET/CT for the Mayo Clinic and Veterans Affairs models, respectively. Of 15 patients with high pretest likelihood and negative findings on PET/CT, 13 (86.7%) did not have lung malignancy. PET/CT improves stratification of cancer patients with indeterminate pulmonary nodules. A substantial number of patients considered at low and intermediate pretest likelihood of malignancy with histology-proven lung malignancy showed abnormal PET/CT findings.
Blozik, Eva; Scherer, Martin; Lacruz, Maria E; Ladwig, Karl-Heinz
2013-12-23
Screening for depressive disorders in the general adult population is recommended, however, it is unclear which instruments combine user friendliness and diagnostic utility. We evaluated the test performance of a yes/no single item screener for depressive disorders ("Have you felt depressed or sad much of the time in the past year?") in comparison to the depressive disorder module of the Patient Health Questionnaire (PHQ-9). Data from 3184 participants of the population-based KORA F3 survey in Augsburg/ Germany were used to analyse sensitivity, specificity, ROC area, positive likelihood ratio (LR+), negative likelihood ratio (LR-), positive predictive value (PPV), and negative predictive value (NPV) of the single item screener in comparison with "depressive mood" and "major depressive disorder" defined according to PHQ-9 (both interviewer-administered versions). In comparison to PHQ-9 "depressive mood", sensitivity was low (46%) with an excellent specificity (94%), (PPV 76%; NPV 82%; LR + 8.04; LR- .572, ROC area .702). When using the more conservative definition for "major depressive disorder", sensitivity increased to 83% with a specificity of 88%. The PPV under the conservative definition was low (32%), but NPV was 99% (LR + 6.65; LR- .196; ROC area .852). Results varied across age groups and between males and females. The single item screener is able to moderately decrease post-test probability of major depressive disorders and to identify populations that should undergo additional, more detailed evaluation for depression. It may have limited utility in combination with additional screening tests or for selection of at-risk populations, but cannot be recommended for routine use as a screening tool in clinical practice.
Zhang, Li; Tang, Min; Chen, Sipan; Lei, Xiaoyan; Zhang, Xiaoling; Huan, Yi
2017-12-01
This meta-analysis was undertaken to review the diagnostic accuracy of PI-RADS V2 for prostate cancer (PCa) detection with multiparametric MR (mp-MR). A comprehensive literature search of electronic databases was performed by two observers independently. Inclusion criteria were original research using the PI-RADS V2 system in reporting prostate MRI. The methodological quality was assessed using the Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) tool. Data necessary to complete 2 × 2 contingency tables were obtained from the included studies. Thirteen studies (2,049 patients) were analysed. This is an initial meta-analysis of PI-RADs V2 and the overall diagnostic accuracy in diagnosing PCa was as follows: pooled sensitivity, 0.85 (0.78-0.91); pooled specificity, 0.71 (0.60-0.80); pooled positive likelihood ratio (LR+), 2.92 (2.09-4.09); pooled negative likelihood ratio (LR-), 0.21 (0.14-0.31); pooled diagnostic odds ratio (DOR), 14.08 (7.93-25.01), respectively. Positive predictive values ranged from 0.54 to 0.97 and negative predictive values ranged from 0.26 to 0.92. Currently available evidence indicates that PI-RADS V2 appears to have good diagnostic accuracy in patients with PCa lesions with high sensitivity and moderate specificity. However, no recommendation regarding the best threshold can be provided because of heterogeneity. • PI-RADS V2 shows good diagnostic accuracy for PCa detection. • Initially pooled specificity of PI-RADS v2 remains moderate. • PCa detection is increased by experienced radiologists. • There is currently a high heterogeneity in prostate diagnostics with MRI.
2013-01-01
Background Screening for depressive disorders in the general adult population is recommended, however, it is unclear which instruments combine user friendliness and diagnostic utility. We evaluated the test performance of a yes/no single item screener for depressive disorders (“Have you felt depressed or sad much of the time in the past year?”) in comparison to the depressive disorder module of the Patient Health Questionnaire (PHQ-9). Methods Data from 3184 participants of the population-based KORA F3 survey in Augsburg/ Germany were used to analyse sensitivity, specificity, ROC area, positive likelihood ratio (LR+), negative likelihood ratio (LR-), positive predictive value (PPV), and negative predictive value (NPV) of the single item screener in comparison with “depressive mood” and “major depressive disorder” defined according to PHQ-9 (both interviewer-administered versions). Results In comparison to PHQ-9 “depressive mood”, sensitivity was low (46%) with an excellent specificity (94%), (PPV 76%; NPV 82%; LR + 8.04; LR- .572, ROC area .702). When using the more conservative definition for “major depressive disorder”, sensitivity increased to 83% with a specificity of 88%. The PPV under the conservative definition was low (32%), but NPV was 99% (LR + 6.65; LR- .196; ROC area .852). Results varied across age groups and between males and females. Conclusions The single item screener is able to moderately decrease post-test probability of major depressive disorders and to identify populations that should undergo additional, more detailed evaluation for depression. It may have limited utility in combination with additional screening tests or for selection of at-risk populations, but cannot be recommended for routine use as a screening tool in clinical practice. PMID:24359193
Beattie, Karen A; Macintyre, Norma J; Pierobon, Jessica; Coombs, Jennifer; Horobetz, Diana; Petric, Alexis; Pimm, Mara; Kean, Walter; Larché, Maggie J; Cividino, Alfred
2011-09-01
To evaluate the sensitivity, specificity and reliability of the gait, arms, legs and spine (GALS) examination to detect signs and symptoms of rheumatoid arthritis when used by physiotherapy students and physiotherapists. Two physiotherapy students and two physiotherapists were trained to perform the GALS examination by viewing an instructional DVD and attending a workshop. Two rheumatologists familiar with the GALS examination also participated in the workshop. All healthcare professionals performed the GALS examination on 25 participants with rheumatoid arthritis recruited through a rheumatology practice and 23 participants without any arthritides recruited from a primary care centre. Each participant was assessed by one rheumatologist, one physiotherapist and one physiotherapy student. Abnormalities of gait, arms, legs and spine, including their location and description, were recorded, along with whether or not a diagnosis of rheumatoid arthritis was suspected. Healthcare professionals understood the study's objective to be their agreement on GALS findings and were unaware that half of the participants had rheumatoid arthritis. Sensitivity, specificity and likelihood ratios were calculated to determine the ability of the GALS examination to screen for rheumatoid arthritis. Using rheumatologists' findings on the study day as the standard for comparison, sensitivity and specificity were 71 to 86% and 69 to 93%, respectively. Positive likelihood ratios ranged from 2.74 to 10.18, while negative likelihood ratios ranged from 0.21 to 0.38. The GALS examination may be a useful tool for physiotherapists to rule out rheumatoid arthritis in a direct access setting. Differences in duration and type of experience of each healthcare professional may contribute to the variation in results. The merits of introducing the GALS examination into physiotherapy curricula and practice should be explored. Copyright © 2010 Chartered Society of Physiotherapy. Published by Elsevier Ltd. All rights reserved.
Wong, Charles; Teitge, Braden; Ross, Marshall; Young, Paul; Robertson, Helen Lee; Lang, Eddy
2018-06-01
Point-of-care ultrasound (POCUS) has been suggested as an initial investigation in the management of renal colic. Our objectives were: 1) to determine the accuracy of POCUS for the diagnosis of nephrolithiasis and 2) to assess its prognostic value in the management of renal colic. The review protocol was registered to the PROSPERO database (CRD42016035331). An electronic database search of MEDLINE, Embase, and PubMed was conducted utilizing subject headings, keywords, and synonyms that address our research question. Bibliographies of included studies and narrative reviews were manually examined. Studies of adult emergency department patients with renal colic symptoms were included. Any degree of hydronephrosis was considered a positive POCUS finding. Accepted criterion standards were computed tomography evidence of renal stone or hydronephrosis, direct stone visualization, or surgical findings. Screening of abstracts, quality assessment with the QUADAS-2 instrument, and data extraction were performed by two reviewers, with discrepancies resolved by consensus with a third reviewer. Test performance was assessed by pooled sensitivity and specificity, calculated likelihood ratios, and a summary receiver operator curve (SROC). The secondary objective of prognostic value was reported as a narrative summary. The electronic search yielded 627 unique titles. After relevance screening, 26 papers underwent full-text review, and nine articles met all inclusion criteria. Of these, five high-quality studies (N = 1,773) were included in the meta-analysis for diagnostic accuracy and the remaining yielded data on prognostic value. The pooled results for sensitivity and specificity were 70.2% (95% confidence interval [CI] = 67.1%-73.2%) and 75.4% (95% CI = 72.5%-78.2%), respectively. The calculated positive and negative likelihood ratios were 2.85 and 0.39. The SROC generated did not show evidence of a threshold effect. Two of the studies in the meta-analysis found that the finding of moderate or greater hydronephrosis yielded a specificity of 94.4% (95% CI = 92.7%-95.8%). Four studies examining prognostic value noted a higher likelihood of a large stone when positive POCUS findings were present. The largest randomized trial showed lower cumulative radiation exposure and no increase in adverse events in those who received POCUS investigation as the initial renal colic investigation. Point-of-care ultrasound has modest diagnostic accuracy for diagnosing nephrolithiasis. The finding of moderate or severe hydronephrosis is highly specific for the presence of any stone, and the presence of any hydronephrosis is suggestive of a larger (>5 mm) stone in those presenting with renal colic. © 2018 by the Society for Academic Emergency Medicine.
Pan, Hui; Ba-Thein, William
2018-01-01
Global Pharma Health Fund (GPHF) Minilab™, a semi-quantitative thin-layer chromatography (TLC)-based commercially available test kit, is widely used in drug quality surveillance globally, but its diagnostic accuracy is unclear. We investigated the diagnostic accuracy of Minilab system for antimicrobials, using high-performance liquid chromatography (HPLC) as reference standard. Following the Minilab protocols and the Pharmacopoeia of the People's Republic of China protocols, Minilab-TLC and HPLC were used to test five common antimicrobials (506 batches) for relative concentration of active pharmaceutical ingredients. The prevalence of poor-quality antimicrobials determined, respectively, by Minilab TLC and HPLC was amoxicillin (0% versus 14.9%), azithromycin (0% versus 17.4%), cefuroxime axetil (14.3% versus 0%), levofloxacin (0% versus 3.0%), and metronidazole (0% versus 38.0%). The Minilab TLC had false-positive and false-negative detection rates of 2.6% (13/506) and 15.2% (77/506) accordingly, resulting in the following test characteristics: sensitivity 0%, specificity 97.0%, positive predictive value 0, negative predictive value 0.8, positive likelihood ratio 0, negative likelihood ratio 1.0, diagnostic odds ratio 0, and adjusted diagnostic odds ratio 0.2. This study demonstrates unsatisfying diagnostic accuracy of Minilab system in screening poor-quality antimicrobials of common use. Using Minilab as a stand-alone system for monitoring drug quality should be reconsidered.
Sykes, Bryan L.; Hoppe, Trevor A.; Maziarka, Kristen D.
2016-01-01
Abstract A 2014 U.S. Department of Justice Best Practices Report advocates that states eliminate HIV-specific criminal penalties except under 2 conditions: when a human immunodeficiency virus (HIV)-positive person intentionally commits a sex crime or transmits the virus by engaging in behavior that poses a significant risk of transmission, regardless of actual transmission. We assess the premise of these exceptions to understand whether these best practices are based on scientific evidence about the population at risk of infection and the risk of sexual violence by HIV-positive individuals. We employ nationally representative, cross-sectional survey data from the Current Population Survey (CPS), the Survey of Inmates in State, Federal, and Local Jails (SISFLJ), and the National Health and Nutrition Survey (NHANES). Data from the CPS, SISFLJ, and NHANES are weighted and combined to analyze bias in the population at risk of HIV. Linear probability models are employed to estimate the likelihood that HIV-positive inmates are incarcerated for violent or sexual offenses, net of socioeconomic factors. We find significant measurement bias in HIV prevalence rates. The selection of national surveys for population denominators distorts contemporary estimates of HIV prevalence by 7% to 20%. Our findings also illustrate that HIV-positive inmates are 10 percentage-points less likely to be incarcerated for violent offenses than HIV-negative inmates. National best practice guidelines may undermine effective social policy that aims to curtail stigma within HIV-positive communities because scientific evidence neither include inmates into prevalence denominators (as a measure of the population at risk) nor assess the likelihood that HIV-positive inmates commit violent or sexual crimes. PMID:27100418
Expressed Likelihood as Motivator: Creating Value through Engaging What’s Real
Higgins, E. Tory; Franks, Becca; Pavarini, Dana; Sehnert, Steen; Manley, Katie
2012-01-01
Our research tested two predictions regarding how likelihood can have motivational effects as a function of how a probability is expressed. We predicted that describing the probability of a future event that could be either A or B using the language of high likelihood (“80% A”) rather than low likelihood (“20% B”), i.e., high rather than low expressed likelihood, would make a present activity more real and engaging, as long as the future event had properties relevant to the present activity. We also predicted that strengthening engagement from the high (vs. low) expressed likelihood of a future event would intensify the value of present positive and negative objects (in opposite directions). Both predictions were supported. There was also evidence that this intensification effect from expressed likelihood was independent of the actual probability or valence of the future event. What mattered was whether high versus low likelihood language was used to describe the future event. PMID:23940411
NASA Astrophysics Data System (ADS)
Cui, Yong; Cao, Wenzhou; Li, Quan; Shen, Hua; Liu, Chao; Deng, Junpeng; Xu, Jiangfeng; Shao, Qiang
2016-05-01
Previous studies indicate that prostate cancer antigen 3 (PCA3) is highly expressed in prostatic tumors. However, its clinical value has not been characterized. The aim of this study was to investigate the clinical value of the urine PCA3 test in the diagnosis of prostate cancer by pooling the published data. Clinical trials utilizing the urine PCA3 test for diagnosing prostate cancer were retrieved from PubMed and Embase. A total of 46 clinical trials including 12,295 subjects were included in this meta-analysis. The pooled sensitivity, specificity, positive likelihood ratio (+LR), negative likelihood ratio (-LR), diagnostic odds ratio (DOR) and area under the curve (AUC) were 0.65 (95% confidence interval [CI]: 0.63-0.66), 0.73 (95% CI: 0.72-0.74), 2.23 (95% CI: 1.91-2.62), 0.48 (95% CI: 0.44-0.52), 5.31 (95% CI: 4.19-6.73) and 0.75 (95% CI: 0.74-0.77), respectively. In conclusion, the urine PCA3 test has acceptable sensitivity and specificity for the diagnosis of prostate cancer and can be used as a non-invasive method for that purpose.
Pourfaraj, Majid; Mohammadi, Nourallah; Taghavi, Mohammadreza
2008-12-01
The purpose of this study is to examine the psychometric properties of Thought-Action Fusion revised scale (TAF-R; Amir, N., freshman, M., Ramsey, B., Neary, E., & Brigidi, B. (2001). Thought-action fusion in individuals with OCD symptoms. Behaviour Research and Therapy, 39, 765-776) in a sample of 565 (321 female) students of Shiraz university. The results of factor analysis with using varimax rotation yielded eight factors that explained 80% variances of total scale. These factors are labeled: moral TAF, responsibility for positive thoughts, likelihood negative events, likelihood positive events, responsibility for negative thoughts, responsibility for harm avoidance, likelihood harm avoidance and likelihood self, respectively. The reliability coefficients of total scale are calculated by two methods: internal consistency and test-retest, which were 0.81 and 0.61, respectively. Concurrent validity showed that TAF-R scores positively and significantly correlate with responsibility, guilt and obsessive-compulsive symptoms. Confirming the expectations, there were people with high obsessive-compulsive symptoms having higher TAF-R scores than those with low symptoms. Moreover, subscales-total correlations showed that the correlations between subscales were low, but subscales correlating with total score of TAF-R were moderated.
Omar, Mohammad Ali; Laniado, Marc
2017-01-01
Introduction There are limited studies evaluating the 3 Incontinence Questionnaire (3IQ) against urodynamics based diagnosis as a reference standard. The 3IQ has been proposed to be useful to evaluate women at the level of primary care. The aim of this study was to determine correlation between 3IQ and video-urodynamics (VUDS) in diagnosing types of urinary incontinence. Material and methods Prospective data was collected on 200 consecutive female patients referred by primary care physicians for urinary incontinence. The mean age was 55 years (range 15–83 years). The patients were evaluated using the 3IQ and video-urodynamics. The 3IQ-based diagnosis of type of female urinary incontinence was compared to VUDS-based results. Sensitivity, specificity, positive likelihood ratios and positive predictive values were calculated. Results On 3IQ based self-evaluation, 28% of patients were classified as having stress urinary incontinence, 20% with urge incontinence and 40% with mixed incontinence. On video-urodynamics, urodynamic stress urinary incontinence (UDSUI) was detected in 56% of patients, detrusor overactivity (DO) in 15% and mixed urinary incontinence (MUI) in 19%. The 3IQ had a sensitivity and specificity respectively of 43% and 92% for UDSUI, 57% and 86% for DO and 58% and 64% for MUI. The corresponding positive likelihood ratios (CI, 95%) were 5.4 (CI 2.6 to 11.3) for stress urinary incontinence, 4.0 (CI 2.5 to 6.5) for DO and 1.62 (1.2 to 2.3) for MUI. The respective positive predictive values were 87% (CI 75% to 95%), 42% (CI 26% to 58%) and 28% (18% to 39%). Conclusions In our study population, stress urinary incontinence was reasonably well predicted by the 3IQ, but the questionnaire under-performed in the diagnoses of detrusor overactivity and mixed urinaryincontinence. PMID:29732212
Validity of self-reported history of Chlamydia trachomatis infection.
Frisse, Ann C; Marrazzo, Jeanne M; Tutlam, Nhial T; Schreiber, Courtney A; Teal, Stephanie B; Turok, David K; Peipert, Jeffrey F
2017-04-01
Chlamydia trachomatis infection is common and largely asymptomatic in women. If untreated, it can lead to sequelae such as pelvic inflammatory disease and infertility. It is unknown whether a patient's self-reported history of Chlamydia trachomatis infection is a valid marker of past infection. Our objective was to evaluate the validity of women's self-reported history of Chlamydia trachomatis infection compared with Chlamydia trachomatis serology, a marker for previous infection. We analyzed data from the Fertility After Contraception Termination study. We compared participants' survey responses with the question, "Have you ever been told by a health care provider that you had Chlamydia?" to serological test results indicating the presence or absence of antibodies to Chlamydia trachomatis as assessed by a microimmunofluorescence assay. Prevalence of past infection, sensitivity, specificity, predictive values, and likelihood ratios were calculated. The Cohen's kappa statistic was computed to assess agreement between self-report and serology. Among 409 participants, 108 (26%) reported having a history of Chlamydia trachomatis infection, whereas 146 (36%) had positive serological test results. Relative to positive microimmunofluorescence assay, the sensitivity and specificity of self-reported history of Chlamydia trachomatis infection were 52.1% (95% confidence interval, 43.6-60.4%) and 87.8% (95% confidence interval, 83.3-91.5%), respectively. The positive predictive value of the self-report was 70.4% (95% confidence interval, 60.8-78.8%), and the negative predictive value was 76.7% (95% confidence interval, 71.6-81.4%). The likelihood ratio was found to be 4.28. Agreement between self-report and serology was found to be moderate (kappa = 0.42, P < .001). Self-reported history of Chlamydia trachomatis infection commonly yields false-negative and false-positive results. When definitive status of past Chlamydia trachomatis infection is needed, serology should be obtained. Copyright © 2016 Elsevier Inc. All rights reserved.
Clinical Diagnosis of Bordetella Pertussis Infection: A Systematic Review.
Ebell, Mark H; Marchello, Christian; Callahan, Maria
2017-01-01
Bordetella pertussis (BP) is a common cause of prolonged cough. Our objective was to perform an updated systematic review of the clinical diagnosis of BP without restriction by patient age. We identified prospective cohort studies of patients with cough or suspected pertussis and assessed study quality using QUADAS-2. We performed bivariate meta-analysis to calculate summary estimates of accuracy and created summary receiver operating characteristic curves to explore heterogeneity by vaccination status and age. Of 381 studies initially identified, 22 met our inclusion criteria, of which 14 had a low risk of bias. The overall clinical impression was the most accurate predictor of BP (positive likelihood ratio [LR+], 3.3; negative likelihood ratio [LR-], 0.63). The presence of whooping cough (LR+, 2.1) and posttussive vomiting (LR+, 1.7) somewhat increased the likelihood of BP, whereas the absence of paroxysmal cough (LR-, 0.58) and the absence of sputum (LR-, 0.63) decreased it. Whooping cough and posttussive vomiting have lower sensitivity in adults. Clinical criteria defined by the Centers for Disease Control and Prevention were sensitive (0.90) but nonspecific. Typical signs and symptoms of BP may be more sensitive but less specific in vaccinated patients. The clinician's overall impression was the most accurate way to determine the likelihood of BP infection when a patient initially presented. Clinical decision rules that combine signs, symptoms, and point-of-care tests have not yet been developed or validated. © Copyright 2017 by the American Board of Family Medicine.
The utility of serum tryptase in the diagnosis of food-induced anaphylaxis.
Wongkaewpothong, Patcharaporn; Pacharn, Punchama; Sripramong, Chaweewan; Boonchoo, Siribangon; Piboonpocanun, Surapon; Visitsunthorn, Nualanong; Vichyanond, Pakit; Jirapongsananuruk, Orathai
2014-07-01
This study investigates the utility of serum tryptase for the confirmation of shrimp-induced anaphylaxis. Patients with a history of shrimp allergy and positive skin prick tests (SPT) to commercial shrimp extract were recruited for shrimp challenges. Serum total tryptase was obtained at baseline and 60 min (peak) after the onset of symptoms. Thirty-nine patients were challenged. There were 12 patients with anaphylaxis, 20 with mild reactions and 7 without symptoms (control group). Characteristic features and baseline tryptase were not different among the 3 groups. The peak tryptase levels were higher than the baseline in anaphylaxis and mild reaction groups (P<0.05). The delta-tryptase (peak minus baseline) and the tryptase ratio (peak divided by baseline) in the anaphylaxis group were higher than the mild reaction and control groups (P<0.01). The optimum cut-off for peak tryptase to confirm anaphylaxis was 2.99 µg/L with 50% sensitivity, 85% specificity, 3.33 positive likelihood ratio (LR) and 0.59 negative LR. The manufacturer's cut-off for peak tryptase was >11.4 µg/L with 17% sensitivity, 100% specificity, infinity positive LR and 0.83 negative LR. The best cut-off for delta-tryptase was ≥0.8 µg/L with 83% sensitivity, 93% specificity, 11.86 positive LR and 0.18 negative LR. The best cut-off for tryptase ratio was ≥1.5 with 92% sensitivity, 96% specificity, 23 positive LR and 0.08 negative LR. The peak tryptase level should be compared with the baseline value to confirm anaphylaxis. The tryptase ratio provide the best sensitivity, specificity, positive and negative LR than a single peak serum tryptase for the confirmation of shrimp-induced anaphylaxis.
ERIC Educational Resources Information Center
Wagler, Ron
2010-01-01
The purpose of this study was to assess the association between United States K-4 preservice teacher's attitudes toward specific animals and the likelihood that the preservice elementary teachers would incorporate these specific animals in their future science curriculum. A strong statistically significant association was found between the…
Gyre and gimble: a maximum-likelihood replacement for Patterson correlation refinement.
McCoy, Airlie J; Oeffner, Robert D; Millán, Claudia; Sammito, Massimo; Usón, Isabel; Read, Randy J
2018-04-01
Descriptions are given of the maximum-likelihood gyre method implemented in Phaser for optimizing the orientation and relative position of rigid-body fragments of a model after the orientation of the model has been identified, but before the model has been positioned in the unit cell, and also the related gimble method for the refinement of rigid-body fragments of the model after positioning. Gyre refinement helps to lower the root-mean-square atomic displacements between model and target molecular-replacement solutions for the test case of antibody Fab(26-10) and improves structure solution with ARCIMBOLDO_SHREDDER.
Pottinger, Paul; Butler-Wu, Susan; Neradilek, Moni Blazej; Merritt, Andrew; Bertelsen, Alexander; Jette, Jocelyn L; Warme, Winston J; Matsen, Frederick A
2012-11-21
Propionibacterium acnes has been grown on culture in half of the reported cases of chronic infection associated with shoulder arthroplasty. The presence of this organism can be overlooked because its subtle presentation may not suggest the need for culture or because, in contrast to many orthopaedic infections, multiple tissue samples and weeks of culture incubation are often necessary to recover this organism. Surgical decisions regarding implant revision and antibiotic therapy must be made before the results of intraoperative cultures are known. In the present study, we sought clinically relevant prognostic evidence that could help to guide treatment decisions. We statistically correlated preoperative and intraoperative observations on 193 shoulder arthroplasty revisions that were performed because of pain, loosening, or stiffness with the results of a Propionibacterium acnes-specific culture protocol. Regression models were used to identify factors predictive of a positive culture for Propionibacterium acnes. One hundred and eight of the 193 revision arthroplasties were associated with positive cultures; 70% of the positive cultures demonstrated growth of Propionibacterium acnes. The rate of positive cultures per shoulder increased with the number of culture specimens obtained from each shoulder. Fifty-five percent of the positive cultures required observation for more than one week. Male sex, humeral osteolysis, and cloudy fluid were each associated with significant increases of ≥ 600% in the likelihood of obtaining a positive Propionibacterium acnes culture. Humeral loosening, glenoid wear, and membrane formation were associated with significant increases of >300% in the likelihood of obtaining a positive Propionibacterium acnes culture. Preoperative and intraoperative factors can be used to help to predict the risk of a positive culture for Propionibacterium acnes. This evidence is clinically relevant to decisions regarding prosthesis removal or retention and the need for immediate antibiotic therapy at the time of revision shoulder arthroplasty before the culture results become available. Prognostic Level II. See Instructions for Authors for a complete description of levels of evidence.
Accuracy of Urine Color to Detect Equal to or Greater Than 2% Body Mass Loss in Men.
McKenzie, Amy L; Muñoz, Colleen X; Armstrong, Lawrence E
2015-12-01
Clinicians and athletes can benefit from field-expedient measurement tools, such as urine color, to assess hydration state; however, the diagnostic efficacy of this tool has not been established. To determine the diagnostic accuracy of urine color assessment to distinguish a hypohydrated state (≥2% body mass loss [BML]) from a euhydrated state (<2% BML) after exercise in a hot environment. Controlled laboratory study. Environmental chamber in a laboratory. Twenty-two healthy men (age = 22 ± 3 years, height = 180.4 ± 8.7 cm, mass = 77.9 ± 12.8 kg, body fat = 10.6% ± 4.6%). Participants cycled at 68% ± 6% of their maximal heart rates in a hot environment (36°C ± 1°C) for 5 hours or until 5% BML was achieved. At the point of each 1% BML, we assessed urine color. Diagnostic efficacy of urine color was assessed using receiver operating characteristic curve analysis, sensitivity, specificity, and likelihood ratios. Urine color was useful as a diagnostic tool to identify hypohydration after exercise in the heat (area under the curve = 0.951, standard error = 0.022; P < .001). A urine color of 5 or greater identified BML ≥2% with 88.9% sensitivity and 84.8% specificity (positive likelihood ratio = 5.87, negative likelihood ratio = 0.13). Under the conditions of acute dehydration due to exercise in a hot environment, urine color assessment can be a valid, practical, inexpensive tool for assessing hydration status. Researchers should examine the utility of urine color to identify a hypohydrated state under different BML conditions.
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.
NASA Astrophysics Data System (ADS)
Kreis, Benjamin
In the absence of meaningful federal action, many states have adopted clean energy policies aimed at reducing carbon emissions. Among these policies is the energy efficiency resource standard (EERS), adopted by 33 states mostly in the last decade, which sets an energy consumption reduction target for some or all regulated utilities within a state. My paper examines what factors affect a state's likelihood of adopting an EERS, and whether those factors are different for EERS policies compared with other clean energy policies. The energy policy literature features many studies of clean energy policy adoption, but none have focused specifically on EERS adoption. I theorized that energy efficiency potential being relatively homogeneously distributed across states (compared to renewable energy potential) and efficiency's relative inexpensiveness as a resource would result in a unique set of factors being associated with the likelihood of EERS adoption. Specifically, I expected that three internal determinants--the presence of utility rate decoupling in a state, a state's political ideology, and the state's average retail price of residential electricity--affect a state's likelihood of adopting an EERS. To test these hypotheses, I estimated several multiple regression models using an event history analysis approach and found that citizen liberalism, level of electricity consumption, and a time counter variable were all statistically significant and positive predictors of state adoption of an EERS, all else equal. I found no association between decoupling or electricity price and EERS adoption, though in the case of the former that may be a result of insufficient data.
Combinatorial pulse position modulation for power-efficient free-space laser communications
NASA Technical Reports Server (NTRS)
Budinger, James M.; Vanderaar, M.; Wagner, P.; Bibyk, Steven
1993-01-01
A new modulation technique called combinatorial pulse position modulation (CPPM) is presented as a power-efficient alternative to quaternary pulse position modulation (QPPM) for direct-detection, free-space laser communications. The special case of 16C4PPM is compared to QPPM in terms of data throughput and bit error rate (BER) performance for similar laser power and pulse duty cycle requirements. The increased throughput from CPPM enables the use of forward error corrective (FEC) encoding for a net decrease in the amount of laser power required for a given data throughput compared to uncoded QPPM. A specific, practical case of coded CPPM is shown to reduce the amount of power required to transmit and receive a given data sequence by at least 4.7 dB. Hardware techniques for maximum likelihood detection and symbol timing recovery are presented.
Desai, Himanshu; Patel, Anil; Patel, Pinal; Grant, Brydon J B; Mador, M Jeffery
2009-11-01
Autotitrating continuous positive airway pressure (auto-CPAP) devices now have a smart card (a pocket-sized card with embedded integrated circuits which records data from the CPAP machine such as CPAP usage, CPAP pressure, large leak, etc.) which can estimate the Apnea-Hypopnea Index (AHI) on therapy. The aim of this study was to determine the accuracy of auto-CPAP in estimating the residual AHI in patients with obstructive sleep apnea (OSA) who were treated with auto-CPAP without a CPAP titration study. We studied 99 patients with OSA from April 2005 to May 2007 who underwent a repeat sleep study using auto-CPAP. The estimated AHI from auto-CPAP was compared with the AHI from an overnight polysomnogram (PSG) on auto-CPAP using Bland-Altman plot and likelihood ratio analyses. A PSG AHI cutoff of five events per hour was used to differentiate patients optimally treated with auto-CPAP from those with residual OSA on therapy. Bland and Altman analysis showed good agreement between auto-CPAP AHI and PSG AHI. There was no significant bias when smart card estimates of AHI at home were compared to smart card estimates obtained in the sleep laboratory. An auto-CPAP cutoff for the AHI of six events per hour was shown to be optimal for differentiating patients with and without residual OSA with a sensitivity of 0.92 (95% confidence interval (CI) 0.76 to 0.98) and specificity of 0.90 (95% CI 0.82 to 0.95) with a positive likelihood ratio (LR) of 9.6 (95% CI 5.1 to 21.5) and a negative likelihood ratio of 0.085 (95% CI 0.02 to 0.25). Auto-CPAP AHI of eight events per hour yielded the optimal sensitivity (0.94, 95% CI 0.73 to 0.99) and specificity (0.90, 95% CI 0.82 to 0.95) with a positive LR of 9.6 (95% CI 5.23 to 20.31) and a negative LR of 0.065 (95% CI 0.004 to 0.279) to identify patients with a PSG AHI of > or = 10 events per hour. Auto-CPAP estimate of AHI may be used to estimate residual AHI in patients with OSA of varying severity treated with auto-CPAP.
Zhang, Li; Tang, Min; Min, Zhiqian; Lu, Jun; Lei, Xiaoyan; Zhang, Xiaoling
2016-06-01
Magnetic resonance imaging (MRI) is increasingly being used to examine patients with suspected breast cancer. To determine the diagnostic performance of combined dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) and diffusion-weighted imaging (DWI) for breast cancer detection. A comprehensive search of the PUBMED, EMBASE, Web of Science, and Cochrane Library databases was performed up to September 2014. Statistical analysis included pooling of sensitivity and specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), diagnostic odds ratio (DOR), and diagnostic accuracy using the summary receiver operating characteristic (SROC). All analyses were conducted using STATA (version 12.0), RevMan (version 5.2), and Meta-Disc 1.4 software programs. Fourteen studies were analyzed, which included a total of 1140 patients with 1276 breast lesions. The pooled sensitivity and specificity of combined DCE-MRI and DWI were 91.6% and 85.5%, respectively. The pooled sensitivity and specificity of DWI-MRI were 86.0% and 75.6%, respectively. The pooled sensitivity and specificity of DCE-MRI were 93.2% and 71.1%. The area under the SROC curve (AUC-SROC) of combined DCE-MRI and DWI was 0.94, the DCE-MRI of 0.85. Deeks testing confirmed no significant publication bias in all studies. Combined DCE-MRI and DWI had superior diagnostic accuracy than either DCE-MRI or DWI alone for the diagnosis of breast cancer. © The Foundation Acta Radiologica 2015.
Halpern, Michael T; Romaire, Melissa A; Haber, Susan G; Tangka, Florence K; Sabatino, Susan A; Howard, David H
2014-10-01
Although state Medicaid programs cover cancer screening, Medicaid beneficiaries are less likely to be screened for cancer and are more likely to present with tumors of an advanced stage than are those with other insurance. The current study was performed to determine whether state Medicaid eligibility and reimbursement policies affect the receipt of breast, cervical, and colon cancer screening among Medicaid beneficiaries. Cross-sectional regression analyses of 2007 Medicaid data from 46 states and the District of Columbia were performed to examine associations between state-specific Medicaid reimbursement/eligibility policies and receipt of cancer screening. The study sample included individuals aged 21 years to 64 years who were enrolled in fee-for-service Medicaid for at least 4 months. Subsamples eligible for each screening test were: Papanicolaou test among 2,136,511 patients, mammography among 792,470 patients, colonoscopy among 769,729 patients, and fecal occult blood test among 753,868 patients. State-specific Medicaid variables included median screening test reimbursement, income/financial asset eligibility requirements, physician copayments, and frequency of eligibility renewal. Increases in screening test reimbursement demonstrated mixed associations (positive and negative) with the likelihood of receiving screening tests among Medicaid beneficiaries. In contrast, increased reimbursements for office visits were found to be positively associated with the odds of receiving all screening tests examined, including colonoscopy (odds ratio [OR], 1.07; 95% confidence interval [95% CI], 1.06-1.08), fecal occult blood test (OR, 1.09; 95% CI, 1.08-1.10), Papanicolaou test (OR, 1.02; 95% CI, 1.02-1.03), and mammography (OR, 1.02; 95% CI, 1.02-1.03). Effects of other state-specific Medicaid policies varied across the screening tests examined. Increased reimbursement for office visits was consistently associated with an increased likelihood of being screened for cancer, and may be an important policy tool for increasing screening among this vulnerable population. © 2014 American Cancer Society.
Zhang, Lifan; Cheng, Xinhe; Bian, Sainan; Song, Yanhua; Li, Qiang; Gao, Mengqiu; Zhang, Yueqiu; Shi, Xiaochun
2017-01-01
Currently available Interferon-γ release assay (IGRA) cannot reliably differentiate active TB (ATB) from non-active TB (non-ATB). A study was performed to evaluate the value of Mycobacterium tuberculosis (MTB) specific Th1 cell immune responses which test IFN-γ and IL-2 simultaneous for differentiating ATB from non-ATB. Forty-nine newly diagnosed inpatients with ATB (26 pulmonary TB and 23 extrapulmonary TB) were enrolled as the ATB group. Forty-five volunteers with latent tuberculosis infection (LTBI) and twenty with evidence of previous TB were enrolled during the same period as the non-ATB group. Clinical examination and MTB specific Th1 cell immune responses were performed for all participants. After being stimulated with ESAT-6 and CFP-10, the median frequencies of single IL-2-, single IFN-γ-, and dual IFN-γ/IL-2-secreting T-cells were all higher in the ATB group than in the non-ATB group (20(8–45) vs. 7(3–13), P<0.001;131(44–308) vs. 10(6–27), P<0.001;25(9–74) vs. 7(3–23), P = 0.001, respectively). Evaluation of the diagnostic performance of detecting single IFN-γ-secreting T cells for pulmonary TB employed a cutoff value of 35 iSFCs/250,000 PBMC. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), positive likelihood ratio (PLR), and negative likelihood ratio (NLR) were 92.3%, 80.0%, 64.9%, 96.3%, 4.62, and 0.10, respectively. For extrapulmonary TB, using a cutoff value of 23 iSFCs/ 250,000 PBMC, the sensitivity, specificity, PPV, NPV, PLR, and NLR were 91.3%, 76.9%, 58.3%, 96.2%, 3.96, and 0.11, respectively. When combining frequencies and proportion of single IFN-γ-secreting T cells, the test sensitivity was 100% in parallel tests and the specificity was 87.7% in serial tests for pulmonary TB. MTB specific Th1 cell immune responses (FluoroSpot) had value for the differentiation of ATB and non-ATB. Further confirmatory studies are indicated. PMID:28531231
Mikula, A L; Hetzel, S J; Binkley, N; Anderson, P A
2017-05-01
Many osteoporosis-related vertebral fractures are unappreciated but their detection is important as their presence increases future fracture risk. We found height loss is a useful tool in detecting patients with vertebral fractures, low bone mineral density, and vitamin D deficiency which may lead to improvements in patient care. This study aimed to determine if/how height loss can be used to identify patients with vertebral fractures, low bone mineral density, and vitamin D deficiency. A hospital database search in which four patient groups including those with a diagnosis of osteoporosis-related vertebral fracture, osteoporosis, osteopenia, or vitamin D deficiency and a control group were evaluated for chart-documented height loss over an average 3 1/2 to 4-year time period. Data was retrieved from 66,021 patients (25,792 men and 40,229 women). A height loss of 1, 2, 3, and 4 cm had a sensitivity of 42, 32, 19, and 14% in detecting vertebral fractures, respectively. Positive likelihood ratios for detecting vertebral fractures were 1.73, 2.35, and 2.89 at 2, 3, and 4 cm of height loss, respectively. Height loss had lower sensitivities and positive likelihood ratios for detecting low bone mineral density and vitamin D deficiency compared to vertebral fractures. Specificity of 1, 2, 3, and 4 cm of height loss was 70, 82, 92, and 95%, respectively. The odds ratios for a patient who loses 1 cm of height being in one of the four diagnostic groups compared to a patient who loses no height was higher for younger and male patients. This study demonstrated that prospective height loss is an effective tool to identify patients with vertebral fractures, low bone mineral density, and vitamin D deficiency although a lack of height loss does not rule out these diagnoses. If significant height loss is present, the high positive likelihood ratios support a further workup.
Décary, Simon; Frémont, Pierre; Pelletier, Bruno; Fallaha, Michel; Belzile, Sylvain; Martel-Pelletier, Johanne; Pelletier, Jean-Pierre; Feldman, Debbie; Sylvestre, Marie-Pierre; Vendittoli, Pascal-André; Desmeules, François
2018-04-01
To assess the validity of diagnostic clusters combining history elements and physical examination tests to diagnose or exclude patellofemoral pain (PFP). Prospective diagnostic study. Orthopedic outpatient clinics, family medicine clinics, and community-dwelling. Consecutive patients (N=279) consulting one of the participating orthopedic surgeons (n=3) or sport medicine physicians (n=2) for any knee complaint. Not applicable. History elements and physical examination tests were obtained by a trained physiotherapist blinded to the reference standard: a composite diagnosis including both physical examination tests and imaging results interpretation performed by an expert physician. Penalized logistic regression (least absolute shrinkage and selection operator) was used to identify history elements and physical examination tests associated with the diagnosis of PFP, and recursive partitioning was used to develop diagnostic clusters. Diagnostic accuracy measures including sensitivity, specificity, positive and negative predictive values, and positive and negative likelihood ratios with associated 95% confidence intervals (CIs) were calculated. Two hundred seventy-nine participants were evaluated, and 75 had a diagnosis of PFP (26.9%). Different combinations of history elements and physical examination tests including the age of participants, knee pain location, difficulty descending stairs, patellar facet palpation, and passive knee extension range of motion were associated with a diagnosis of PFP and used in clusters to accurately discriminate between individuals with PFP and individuals without PFP. Two diagnostic clusters developed to confirm the presence of PFP yielded a positive likelihood ratio of 8.7 (95% CI, 5.2-14.6) and 3 clusters to exclude PFP yielded a negative likelihood ratio of .12 (95% CI, .06-.27). Diagnostic clusters combining common history elements and physical examination tests that can accurately diagnose or exclude PFP compared to various knee disorders were developed. External validation is required before clinical use. Copyright © 2017 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.
Intraoperative Physical Examination for Diagnosis of Interosseous Ligament Rupture-Cadaveric Study.
Kachooei, Amir Reza; Rivlin, Michael; Wu, Fei; Faghfouri, Aram; Eberlin, Kyle R; Ring, David
2015-09-01
To study the intraobserver and interobserver reliability of the diagnosis of interosseous ligament (IOL) rupture in a cadaver model. On 12 fresh frozen cadavers, radial heads were cut using an identical incision and osteotomy. After randomization, the soft tissues of the limbs were divided into 4 groups: both IOL and triangular fibrocartilage (TFCC) intact; IOL disruption but TFCC intact; both IOL and TFCC divided; and IOL intact but TFCC divided. All incisions had identical suturing. After standard instruction and demonstration of radius pull-push and radius lateral pull tests, 10 physician evaluators with different levels of experience examined the cadaver limbs in a standardized way (elbow at 90° with the forearm held in both supination and pronation) and were asked to classify them into one of the 4 groups. Next, the same examiners were asked to re-examine the limbs after randomly changing the order of examination. The interobserver reliability of agreement for the diagnosis of IOL injury (groups 2 and 3) was fair in both rounds of examination and the intraobserver reliability was moderate. The intra- and interobserver reliabilities of agreement for the 4 groups of injuries among the examiners were fair in both rounds of examination. The sensitivity, specificity, accuracy, positive, and negative predictive values were all around 70%. The likelihood of a positive test corresponding with the presence of IOL rupture (positive likelihood ratio) was 2.2. The likelihood of a negative test correctly diagnosing an intact IOL was 0.40. In cadavers, intraoperative tests had fair reliability and 70% accuracy for the diagnosis of IOL rupture using the push-pull and lateral pull maneuvers. The level of experience did not have any effect on the correct diagnosis of intact versus disrupted IOL. Although not common, some failure of surgeries for traumatic elbow fracture-dislocations is because of failure in timely diagnosis of IOL disruption. Copyright © 2015 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.
Zhang, Aimi; Li, Panli; Liu, Qiufang; Song, Shaoli
2017-01-01
This study aimed to evaluate the diagnostic role of breast-specific gamma camera imaging (BSGI) with technetium-99m-methoxy isobutyl isonitrile ( 99m Tc-MIBI) and magnetic resonance imaging (MRI) in patients with breast cancer through a meta-analysis. Three reviewers searched articles published in medical journals before June 2016 in MEDLINE, EMBASE and Springer Databases; the references listed in original articles were also retrieved. We used the quality assessment of diagnostic accuracy studies (QUADAS) tool to assess the quality of the included studies. Heterogeneity, pooled sensitivity and specificity, positive likelihood ratio, negative likelihood ratio, diagnostic odds ratio (DOR) and summary receiver operating characteristic (SROC) curves were calculated by Meta-DiSc software to estimate the diagnostic performance of BSGI and MRI. Ten studies with 517 patients were included after meeting the inclusion criteria. We did a subgroup analysis of the same data type. The pooled sensitivities of BSGI and MRI were: 0.84 (95% CI, 0.79-0.88) and 0.89 (95% CI, 0.84-0.92) respectively, and the pooled specificities of BSGI and MRI were: 0.82 (95% CI, 0.74-0.88) and 0.39 (95% CI, 0.30-0.49) respectively. The areas under the SROC curve of BSGI and MRI were 0.93 and 0.72 respectively. The results of our meta-analysis indicated that compared with MRI, BSGI has similar sensitivity, higher specificity, better diagnostic performance, and can be widely used in clinical practice.
The cultural influences on help-seeking among a national sample of victimized Latino women.
Sabina, Chiara; Cuevas, Carlos A; Schally, Jennifer L
2012-06-01
The current study examined the influence of legal status and cultural variables (i.e., acculturation, gender role ideology and religious coping) on the formal and informal help-seeking efforts of Latino women who experienced interpersonal victimization. The sample was drawn from the Sexual Assault Among Latinas (SALAS) Study that surveyed 2,000 self-identified adult Latino women. The random digit dial methodology employed in high-density Latino neighborhoods resulted in a cooperation rate of 53.7%. Women who experienced lifetime victimization (n = 714) reported help-seeking efforts in response to their most distressful victimization event that occurred in the US. Approximately one-third of the women reported formal help-seeking and about 70% of women reported informal help-seeking. Help-seeking responses were generally not predicted by the cultural factors measured, with some exceptions. Anglo orientation and negative religious coping increased the likelihood of formal help-seeking. Positive religious coping, masculine gender role and Anglo acculturation increased the likelihood of specific forms of informal help-seeking. Latino orientation decreased the likelihood of talking to a sibling. Overall, these findings reinforce the importance of bilingual culturally competent services as cultural factors shape the ways in which women respond to victimization either formally or within their social networks.
Conde-Agudelo, Agustin; Romero, Roberto
2015-12-01
To determine the accuracy of changes in transvaginal sonographic cervical length over time in predicting preterm birth in women with singleton and twin gestations. PubMed, Embase, Cinahl, Lilacs, and Medion (all from inception to June 30, 2015), bibliographies, Google scholar, and conference proceedings. Cohort or cross-sectional studies reporting on the predictive accuracy for preterm birth of changes in cervical length over time. Two reviewers independently selected studies, assessed the risk of bias, and extracted the data. Summary receiver-operating characteristic curves, pooled sensitivities and specificities, and summary likelihood ratios were generated. Fourteen studies met the inclusion criteria, of which 7 provided data on singleton gestations (3374 women) and 8 on twin gestations (1024 women). Among women with singleton gestations, the shortening of cervical length over time had a low predictive accuracy for preterm birth at <37 and <35 weeks of gestation with pooled sensitivities and specificities, and summary positive and negative likelihood ratios ranging from 49% to 74%, 44% to 85%, 1.3 to 4.1, and 0.3 to 0.7, respectively. In women with twin gestations, the shortening of cervical length over time had a low to moderate predictive accuracy for preterm birth at <34, <32, <30, and <28 weeks of gestation with pooled sensitivities and specificities, and summary positive and negative likelihood ratios ranging from 47% to 73%, 84% to 89%, 3.8 to 5.3, and 0.3 to 0.6, respectively. There were no statistically significant differences between the predictive accuracies for preterm birth of cervical length shortening over time and the single initial and/or final cervical length measurement in 8 of 11 studies that provided data for making these comparisons. In the largest and highest-quality study, a single measurement of cervical length obtained at 24 or 28 weeks of gestation was significantly more predictive of preterm birth than any decrease in cervical length between these gestational ages. Change in transvaginal sonographic cervical length over time is not a clinically useful test to predict preterm birth in women with singleton or twin gestations. A single cervical length measurement obtained between 18 and 24 weeks of gestation appears to be a better test to predict preterm birth than changes in cervical length over time. Published by Elsevier Inc.
Sabet, Fatemeh Alsadat; Majdzadeh, Reza; Mostafazadeh Davani, Babak; Heidari, Kazem; Soltani, Akbar
2015-01-01
To propose an evidence based diagnostic algorithm using mass characteristics to determine malignancy in patients with adrenal incidentaloma by CTscan. A systematic review in Medline, Scopus, relevant reference books and desk searching was performed up to January 2016 with relevant reference checking. The summery estimates of sensitivity, specificity, positive and negative likelihood ratio of different characteristics were calculated in two groups of the articles investigating the cases without previous malignancy and the articles investigating the oncologic cases. Thirty six articles were included in this study. In the first group with no history of malignancy a positive and negative LR of 3.1 and 0.13 in 4 cm threshold and positive and negative LR of 2.85 and 0 in 10HU density were found. In the second group with history of malignancy positive and negative LR of 2.3 and 0.27 in 3 cm threshold and positive and negative LR of 3.6 and 0.08 in 20HU density were resulted. The results retrieved in this study considering the limitations show that adrenal incidentaloma with a size less than 4 cm or a mass larger than 4 cm with density less than 10HU in the first group can be managed with imaging follow up. For masses larger than 4 cm with density more than 10HU another diagnostic procedure should be performed. In the second group an adrenal mass larger than 3 cm or less than 3 cm with density more than 20HU should go under operation. But masses smaller than 3 cm with less than 20HU density can be followed by imaging.
Maternal regulation of child affect in externalizing and typically-developing children.
Lougheed, Jessica P; Hollenstein, Tom; Lichtwarck-Aschoff, Anna; Granic, Isabela
2015-02-01
Temporal contingencies between children's affect and maternal behavior play a role in the development of children's externalizing problems. The goal of the current study was to use a microsocial approach to compare dyads with externalizing dysregulation (N =191) to healthy controls (N = 54) on maternal supportive regulation of children's negative and positive affect. Children were between the ages of 8 and 12 years. Mother-child dyads participated in conflict and positive discussions, and child affect and maternal supportive affect regulation were coded in real time. First, no group differences on overall levels of mother supportive regulation or child affect were found. Second, three event history analyses in a 2-level Cox hazard regression framework were used to predict the hazard rate of (a) maternal supportiveness, and of children's transitions (b) out of negative affect and (c) into positive affect. The hazard rate of maternal supportiveness, regardless of child affect, was not different between groups. However, as expected, the likelihood of mothers' supportive responses to children's negative affect was lower in externalizing than comparison dyads. In addition, children with externalizing problems were significantly less likely than typically developing children to transition out of negative affect in response to maternal supportiveness. The likelihood of both typically developing children and children with externalizing problems transitioning into positive affect were not related to specific occurrences of maternal supportiveness. Results of the current study show the importance of temporal dynamics in mother-child interactions in the emergence of children's externalizing problems. PsycINFO Database Record (c) 2015 APA, all rights reserved.
Buscombe, Richard; Greenlees, Iain; Holder, Tim; Thelwell, Richard; Rimmer, Matt
2006-12-01
In this study, we examined the impact of a male opponent's pre-match body language and clothing (general vs. sports-specific) on how his performances were judged by an observer. Forty male tennis players viewed videos of a male target tennis player warming up and then observed playing footage of the target. Each participant viewed the target player warming up displaying one of four combinations of body language and clothing (positive body language/tennis-specific clothing; positive body language/general sportswear; negative body language/tennis-specific clothing; negative body language/general sportswear). Participants rated the performance of the tennis player and gave their perceptions of the likely outcome of a tennis match with the target player. Analyses of variance indicated that clothing and body language had an interactive effect on both outcome expectations and ratings of performance. The findings support the contention that the initial impressions athletes form of their opponents can influence the way in which they judge the performances of opponents and their perceived likelihood of success against the same opponents.
Markov-modulated Markov chains and the covarion process of molecular evolution.
Galtier, N; Jean-Marie, A
2004-01-01
The covarion (or site specific rate variation, SSRV) process of biological sequence evolution is a process by which the evolutionary rate of a nucleotide/amino acid/codon position can change in time. In this paper, we introduce time-continuous, space-discrete, Markov-modulated Markov chains as a model for representing SSRV processes, generalizing existing theory to any model of rate change. We propose a fast algorithm for diagonalizing the generator matrix of relevant Markov-modulated Markov processes. This algorithm makes phylogeny likelihood calculation tractable even for a large number of rate classes and a large number of states, so that SSRV models become applicable to amino acid or codon sequence datasets. Using this algorithm, we investigate the accuracy of the discrete approximation to the Gamma distribution of evolutionary rates, widely used in molecular phylogeny. We show that a relatively large number of classes is required to achieve accurate approximation of the exact likelihood when the number of analyzed sequences exceeds 20, both under the SSRV and among site rate variation (ASRV) models.
Diagnostic Capability of Spectral Domain Optical Coherence Tomography for Glaucoma
Wu, Huijuan; de Boer, Johannes F.; Chen, Teresa C.
2012-01-01
Purpose To determine the diagnostic capability of spectral domain optical coherence tomography (OCT) in glaucoma patients with visual field (VF) defects. Design Prospective, cross-sectional study. Methods Setting Participants were recruited from a university hospital clinic. Study Population One eye of 85 normal subjects and 61 glaucoma patients [with average VF mean deviation (MD) of -9.61 ± 8.76 dB] were randomly selected for the study. A subgroup of the glaucoma patients with early VF defects was calculated separately. Observation Procedures Spectralis OCT circular scans were performed to obtain peripapillary retinal nerve fiber layer (RNFL) thicknesses. The RNFL diagnostic parameters based on the normative database were used alone or in combination for identifying glaucomatous RNFL thinning. Main Outcome Measures To evaluate diagnostic performance, calculations included areas under the receiver operating characteristic curve (AROC), sensitivity, specificity, positive predictive value, negative predictive value, positive likelihood ratio, and negative likelihood ratio. Results Overall RNFL thickness had the highest AROC value (0.952 for all patients, 0.895 for the early glaucoma subgroup). For all patients, the highest sensitivity (98.4%, CI 96.3-100%) was achieved by using two criteria: ≥1 RNFL sectors being abnormal at the < 5% level, and overall classification of borderline or outside normal limits, with specificities of 88.9% (CI 84.0-94.0%) and 87.1% (CI 81.6-92.5%) respectively for these two criteria. Conclusions Statistical parameters for evaluating the diagnostic performance of the Spectralis spectral domain OCT were good for early perimetric glaucoma and excellent for moderately-advanced perimetric glaucoma. PMID:22265147
Mallampati test as a predictor of laryngoscopic view.
Adamus, Milan; Fritscherova, Sarka; Hrabalek, Lumir; Gabrhelik, Tomas; Zapletalova, Jana; Janout, Vladimir
2010-12-01
To determine the accuracy of the modified Mallampati test for predicting difficult tracheal intubation. A cross-sectional, clinical, observational, non-blinded study. A quality analysis of anesthetic care. Operating theatres and department of anesthesiology in a university hospital. Following the local ethics committee approval and patients' informed consent to anesthesia, all adult patients (> 18 yrs) presenting for any type of non-emergency surgical procedures under general anesthesia requiring endotracheal intubation were enrolled. Prior to anesthesia, Samsoon and Young's modification of the Mallampati test (modified Mallampati test) was performed. Following induction, the anesthesiologist described the laryngoscopic view using the Cormack-Lehane scale. Classes 3 or 4 of the modified Mallampati test were considered a predictor of difficult intubation. Grades 3 or 4 of the Cormack-Lehane classification of the laryngoscopic view were defined as impaired glottic exposure. The sensitivity, specificity, positive and negative predictive value, relative risk, likelihood ratio and accuracy of the modified Mallampati test were calculated on 2x2 contingency tables. Of the total 1,518 patients enrolled, 48 had difficult intubation (3.2%). We failed to detect as many as 35.4% patients in whom glottis exposure during direct laryngoscopy was inadequate (sensitivity 0.646). Compared to the original article by Mallampati, we found lower specificity (0.824 vs. 0.995), lower positive predictive value (0.107 vs. 0.933), higher negative predictive value (0.986 vs. 0.928), lower likelihood ratio (3.68 vs. 91.0) and accuracy (0.819 vs. 0.929). When used as a single examination, the modified Mallampati test is of limited value in predicting difficult intubation.
Automatic optimism: the affective basis of judgments about the likelihood of future events.
Lench, Heather C
2009-05-01
People generally judge that the future will be consistent with their desires, but the reason for this desirability bias is unclear. This investigation examined whether affective reactions associated with future events are the mechanism through which desires influence likelihood judgments. In 4 studies, affective reactions were manipulated for initially neutral events. Compared with a neutral condition, events associated with positive reactions were judged as likely to occur, and events associated with negative reactions were judged as unlikely to occur. Desirability biases were reduced when participants could misattribute affective reactions to a source other than future events, and the relationship between affective reactions and judgments was influenced when approach and avoidance motivations were independently manipulated. Together, these findings demonstrate that positive and negative affective reactions to potential events cause the desirability bias in likelihood judgments and suggest that this effect occurs because of a tendency to approach positive possibilities and avoid negative possibilities. (c) 2009 APA, all rights reserved.
The effect of prenatal care on birthweight: a full-information maximum likelihood approach.
Rous, Jeffrey J; Jewell, R Todd; Brown, Robert W
2004-03-01
This paper uses a full-information maximum likelihood estimation procedure, the Discrete Factor Method, to estimate the relationship between birthweight and prenatal care. This technique controls for the potential biases surrounding both the sample selection of the pregnancy-resolution decision and the endogeneity of prenatal care. In addition, we use the actual number of prenatal care visits; other studies have normally measured prenatal care as the month care is initiated. We estimate a birthweight production function using 1993 data from the US state of Texas. The results underscore the importance of correcting for estimation problems. Specifically, a model that does not control for sample selection and endogeneity overestimates the benefit of an additional visit for women who have relatively few visits. This overestimation may indicate 'positive fetal selection,' i.e., women who did not abort may have healthier babies. Also, a model that does not control for self-selection and endogenity predicts that past 17 visits, an additional visit leads to lower birthweight, while a model that corrects for these estimation problems predicts a positive effect for additional visits. This result shows the effect of mothers with less healthy fetuses making more prenatal care visits, known as 'adverse selection' in prenatal care. Copyright 2003 John Wiley & Sons, Ltd.
Alavi, Afsaneh; Sibbald, R Gary; Nabavizadeh, Reza; Valaei, Farnaz; Coutts, Pat; Mayer, Dieter
2015-12-01
To determine the accuracy of audible arterial foot signals with an audible handheld Doppler ultrasound for identification of significant peripheral arterial disease as a simple, quick, and readily available bedside screening tool. Two hundred consecutive patients referred to an interprofessional wound care clinic underwent audible handheld Doppler ultrasound of both legs. As a control and comparator, a formal bilateral lower leg vascular study including the calculation of Ankle Brachial Pressure Index and toe pressure (TP) was performed at the vascular lab. Diagnostic reliability of audible handheld Doppler ultrasound was calculated versus Ankle Brachial Pressure Index as the gold standard test. A sensitivity of 42.8%, a specificity of 97.5%, negative predictive value of 94.10%, positive predictive value of 65.22%, positive likelihood ratio of 17.52, and negative likelihood ratio of 0.59. The univariable logistic regression model had an area under the curve of 0.78. There was a statistically significant difference at the 5% level between univariable and multivariable area under the curves of the dorsalis pedis and posterior tibial models (p < 0.001). Audible handheld Doppler ultrasound proved to be a reliable, simple, rapid, and inexpensive bedside exclusion test of peripheral arterial disease in diabetic and nondiabetic patients. © The Author(s) 2015.
Is the MARS questionnaire a reliable measure of medication adherence in childhood asthma?
Garcia-Marcos, Patricia W; Brand, Paul L P; Kaptein, Adrian A; Klok, Ted
2016-12-01
To assess the reliability of the Medication Adherence Report Scale (MARS-5) for assessing adherence in clinical practice and research. Prospective cohort study following electronically measured inhaled corticosteroids (ICS) adherence for 1 year in 2-13-year-old children with persistent asthma. The relationship between electronically measured adherence and MARS-5 scores (ranging from 5 to 25) was assessed by Spearman's rank correlation coefficient. A ROC (receiver operating characteristic) curve was performed testing MARS-5 against electronically measured adherence. Sensitivity, specificity, positive and negative likelihood ratios of the closest MARS-5 cut-off values to the top left-hand corner of the ROC curve were calculated. High MARS scores were obtained (median 24, interquartile range 22-24). Despite a statistically significant correlation between MARS-5 and electronically assessed adherence (Spearman's rho = 0.47; p < 0.0001), there was considerable variation of adherence rates at every MARS-5 score. The area under the ROC curve was 0.7188. A MARS-5 score ≥23 had the best predictive ability for electronically assessed adherence, but positive and negative likelihood ratios were too small to be useful (1.65 and 0.27, respectively). Self-report using MARS-5 is too inaccurate to be a useful measure of adherence in children with asthma, both in clinical practice and in research.
Nimesh, Manoj; Joon, Deepali; Pathak, Anil Kumar; Saluja, Daman
2013-11-01
Indian contribution to global burden of tuberculosis is about 26%. In the present study we have developed an in-house PCR assay using primers for sdaA gene of Mycobacterium tuberculosis and evaluated against already established primers devR, IS6110, MPB64, rpoB primers for diagnosis of pulmonary tuberculosis. Using universal sample preparation (USP) method, DNA was extracted from sputum specimens of 412 symptomatic patients from Delhi, India. The DNA so extracted was used as template for PCR amplification using primers targeting sdaA, devR, IS6110, MPB64 and rpoB genes. Out of 412, 149 specimens were considered positive based on composite reference standard (CRS) criteria. The in-house designed sdaA PCR showed high specificity (96.5%), the high positive likelihood ratio (28), the high sensitivity (95.9%), and the very low negative likelihood ratio (0.04) in comparison to CRS. Based on our results, the sdaA PCR assay can be considered as one of the most reliable diagnostic tests in comparison to other PCR based detection methods. Copyright © 2013 The British Infection Association. Published by Elsevier Ltd. All rights reserved.
Estimating the variance for heterogeneity in arm-based network meta-analysis.
Piepho, Hans-Peter; Madden, Laurence V; Roger, James; Payne, Roger; Williams, Emlyn R
2018-04-19
Network meta-analysis can be implemented by using arm-based or contrast-based models. Here we focus on arm-based models and fit them using generalized linear mixed model procedures. Full maximum likelihood (ML) estimation leads to biased trial-by-treatment interaction variance estimates for heterogeneity. Thus, our objective is to investigate alternative approaches to variance estimation that reduce bias compared with full ML. Specifically, we use penalized quasi-likelihood/pseudo-likelihood and hierarchical (h) likelihood approaches. In addition, we consider a novel model modification that yields estimators akin to the residual maximum likelihood estimator for linear mixed models. The proposed methods are compared by simulation, and 2 real datasets are used for illustration. Simulations show that penalized quasi-likelihood/pseudo-likelihood and h-likelihood reduce bias and yield satisfactory coverage rates. Sum-to-zero restriction and baseline contrasts for random trial-by-treatment interaction effects, as well as a residual ML-like adjustment, also reduce bias compared with an unconstrained model when ML is used, but coverage rates are not quite as good. Penalized quasi-likelihood/pseudo-likelihood and h-likelihood are therefore recommended. Copyright © 2018 John Wiley & Sons, Ltd.
Labronici, Pedro José; Ferreira, Leonardo Termis; Dos Santos Filho, Fernando Claudino; Pires, Robinson Esteves Santos; Gomes, Davi Coutinho Fonseca Fernandes; da Silva, Luiz Henrique Penteado; Gameiro, Vinicius Schott
2017-02-01
Several so-called casting indices are available for objective evaluation of plaster cast quality. The present study sought to investigate four of these indices (gap index, padding index, Canterbury index, and three-point index) as compared to a reference standard (cast index) for evaluation of plaster cast quality after closed reduction of pediatric displaced distal forearm fractures. Forty-three radiographs from patients with displaced distal forearm fractures requiring manipulation were reviewed. Accuracy, sensitivity, specificity, false-positive probability, false-negative probability, positive predictive value, negative predictive value, positive likelihood ratio, and negative likelihood ratio were calculated for each of the tested indices. Comparison among indices revealed diagnostic agreement in only 4.7% of cases. The strongest correlation with the cast index was found for the gap index, with a Spearman correlation coefficient of 0.94. The gap index also displayed the best agreement with the cast index, with both indices yielding the same result in 79.1% of assessments. When seeking to assess plaster cast quality, the cast index and gap index should be calculated; if both indices agree, a decision on quality can be made. If the cast and gap indices disagree, the padding index can be calculated as a tiebreaker, and the decision based on the most frequent of the three results. Calculation of the three-point index and Canterbury index appears unnecessary. Copyright © 2016 Elsevier Ltd. All rights reserved.
Sabour, Siamak
2018-03-08
The purpose of this letter, in response to Hall, Mehta, and Fackrell (2017), is to provide important knowledge about methodology and statistical issues in assessing the reliability and validity of an audiologist-administered tinnitus loudness matching test and a patient-reported tinnitus loudness rating. The author uses reference textbooks and published articles regarding scientific assessment of the validity and reliability of a clinical test to discuss the statistical test and the methodological approach in assessing validity and reliability in clinical research. Depending on the type of the variable (qualitative or quantitative), well-known statistical tests can be applied to assess reliability and validity. The qualitative variables of sensitivity, specificity, positive predictive value, negative predictive value, false positive and false negative rates, likelihood ratio positive and likelihood ratio negative, as well as odds ratio (i.e., ratio of true to false results), are the most appropriate estimates to evaluate validity of a test compared to a gold standard. In the case of quantitative variables, depending on distribution of the variable, Pearson r or Spearman rho can be applied. Diagnostic accuracy (validity) and diagnostic precision (reliability or agreement) are two completely different methodological issues. Depending on the type of the variable (qualitative or quantitative), well-known statistical tests can be applied to assess validity.
Ala-Houhala, M; Koukila-Kähkölä, P; Antikainen, J; Valve, J; Kirveskari, J; Anttila, V-J
2018-03-01
To assess the clinical use of panfungal PCR for diagnosis of invasive fungal diseases (IFDs). We focused on the deep tissue samples. We first described the design of panfungal PCR, which is in clinical use at Helsinki University Hospital. Next we retrospectively evaluated the results of 307 fungal PCR tests performed from 2013 to 2015. Samples were taken from normally sterile tissues and fluids. The patient population was nonselected. We classified the likelihood of IFD according to the criteria of the European Organization for Research and Treatment of Cancer/Invasive Fungal Infections Cooperative Group and the National Institute of Allergy and Infectious Diseases Mycoses Study Group (EORTC/MSG), comparing the fungal PCR results to the likelihood of IFD along with culture and microscopy results. There were 48 positive (16%) and 259 negative (84%) PCR results. The sensitivity and specificity of PCR for diagnosing IFDs were 60.5% and 91.7%, respectively, while the negative predictive value and positive predictive value were 93.4% and 54.2%, respectively. The concordance between the PCR and the culture results was 86% and 87% between PCR and microscopy, respectively. Of the 48 patients with positive PCR results, 23 had a proven or probable IFD. Fungal PCR can be useful for diagnosing IFDs in deep tissue samples. It is beneficial to combine fungal PCR with culture and microscopy. Copyright © 2017 European Society of Clinical Microbiology and Infectious Diseases. Published by Elsevier Ltd. All rights reserved.
Risk management and precaution: insights on the cautious use of evidence.
Hrudey, Steve E; Leiss, William
2003-01-01
Risk management, done well, should be inherently precautionary. Adopting an appropriate degree of precaution with respect to feared health and environmental hazards is fundamental to risk management. The real problem is in deciding how precautionary to be in the face of inevitable uncertainties, demanding that we understand the equally inevitable false positives and false negatives from screening evidence. We consider a framework for detection and judgment of evidence of well-characterized hazards, using the concepts of sensitivity, specificity, positive predictive value, and negative predictive value that are well established for medical diagnosis. Our confidence in predicting the likelihood of a true danger inevitably will be poor for rare hazards because of the predominance of false positives; failing to detect a true danger is less likely because false negatives must be rarer than the danger itself. Because most controversial environmental hazards arise infrequently, this truth poses a dilemma for risk management. PMID:14527835
Modeling false positive detections in species occurrence data under different study designs.
Chambert, Thierry; Miller, David A W; Nichols, James D
2015-02-01
The occurrence of false positive detections in presence-absence data, even when they occur infrequently, can lead to severe bias when estimating species occupancy patterns. Building upon previous efforts to account for this source of observational error, we established a general framework to model false positives in occupancy studies and extend existing modeling approaches to encompass a broader range of sampling designs. Specifically, we identified three common sampling designs that are likely to cover most scenarios encountered by researchers. The different designs all included ambiguous detections, as well as some known-truth data, but their modeling differed in the level of the model hierarchy at which the known-truth information was incorporated (site level or observation level). For each model, we provide the likelihood, as well as R and BUGS code needed for implementation. We also establish a clear terminology and provide guidance to help choosing the most appropriate design and modeling approach.
Karzmark, Peter; Deutsch, Gayle K
2018-01-01
This investigation was designed to determine the predictive accuracy of a comprehensive neuropsychological and brief neuropsychological test battery with regard to the capacity to perform instrumental activities of daily living (IADLs). Accuracy statistics that included measures of sensitivity, specificity, positive and negative predicted power and positive likelihood ratio were calculated for both types of batteries. The sample was drawn from a general neurological group of adults (n = 117) that included a number of older participants (age >55; n = 38). Standardized neuropsychological assessments were administered to all participants and were comprised of the Halstead Reitan Battery and portions of the Wechsler Adult Intelligence Scale-III. A comprehensive test battery yielded a moderate increase over base-rate in predictive accuracy that generalized to older individuals. There was only limited support for using a brief battery, for although sensitivity was high, specificity was low. We found that a comprehensive neuropsychological test battery provided good classification accuracy for predicting IADL capacity.
Gengsheng Qin; Davis, Angela E; Jing, Bing-Yi
2011-06-01
For a continuous-scale diagnostic test, it is often of interest to find the range of the sensitivity of the test at the cut-off that yields a desired specificity. In this article, we first define a profile empirical likelihood ratio for the sensitivity of a continuous-scale diagnostic test and show that its limiting distribution is a scaled chi-square distribution. We then propose two new empirical likelihood-based confidence intervals for the sensitivity of the test at a fixed level of specificity by using the scaled chi-square distribution. Simulation studies are conducted to compare the finite sample performance of the newly proposed intervals with the existing intervals for the sensitivity in terms of coverage probability. A real example is used to illustrate the application of the recommended methods.
Simons, Jeffrey S.; Wills, Thomas A.; Neal, Dan J.
2016-01-01
This research tested a multilevel structural equation model of associations between 3 aspects of affective functioning (state affect, trait affect, and affective lability) and 3 alcohol outcomes (likelihood of drinking, quantity on drinking days, and dependence symptoms) in a sample of 263 college students. Participants provided 49 days of experience sampling data over 1.3 years in a longitudinal burst design. Within-person results: At the daily level, positive affect was directly associated with greater likelihood and quantity of alcohol consumption. Daily negative affect was directly associated with higher consumption on drinking days and with higher dependence symptoms. Between-person direct effects: Affect lability was associated with higher trait negative, but not positive, affect. Trait positive affect was inversely associated with the proportion of drinking days, whereas negative affectivity predicted a greater proportion of drinking days. Affect lability exhibited a direct association with dependence symptoms. Between-person indirect effects: Trait positive affect was associated with fewer dependence symptoms via proportion of drinking days. Trait negative affect was associated with greater dependence symptoms via proportion of drinking days. The results distinguish relations of positive and negative affect to likelihood versus amount of drinking and state versus trait drinking outcomes, and highlight the importance of affect variability for predicting alcohol dependence symptoms. PMID:24933278
Kamerman, Peter R.; Veliotes, Demetri G. A.; Phillips, Tudor J.; Asboe, David; Boffito, Marta; Rice, Andrew S. C.
2016-01-01
HIV-associated sensory peripheral neuropathy (HIV-SN) afflicts approximately 50% of patients on antiretroviral therapy, and is associated with significant neuropathic pain. Simple accurate diagnostic instruments are required for clinical research and daily practice in both high- and low-resource setting. A 4-item clinical tool (CHANT: Clinical HIV-associated Neuropathy Tool) assessing symptoms (pain and numbness) and signs (ankle reflexes and vibration sense) was developed by selecting and combining the most accurate measurands from a deep phenotyping study of HIV positive people (Pain In Neuropathy Study–HIV-PINS). CHANT was alpha-tested in silico against the HIV-PINS dataset and then clinically validated and field-tested in HIV-positive cohorts in London, UK and Johannesburg, South Africa. The Utah Early Neuropathy Score (UENS) was used as the reference standard in both settings. In a second step, neuropathic pain in the presence of HIV-SN was assessed using the Douleur Neuropathique en 4 Questions (DN4)-interview and a body map. CHANT achieved high accuracy on alpha-testing with sensitivity and specificity of 82% and 90%, respectively. In 30 patients in London, CHANT diagnosed 43.3% (13/30) HIV-SN (66.7% with neuropathic pain); sensitivity = 100%, specificity = 85%, and likelihood ratio = 6.7 versus UENS, internal consistency = 0.88 (Cronbach alpha), average item-total correlation = 0.73 (Spearman’s Rho), and inter-tester concordance > 0.93 (Spearman’s Rho). In 50 patients in Johannesburg, CHANT diagnosed 66% (33/50) HIV-SN (78.8% neuropathic pain); sensitivity = 74.4%, specificity = 85.7%, and likelihood ratio = 5.29 versus UENS. A positive CHANT score markedly increased of pre- to post-test clinical certainty of HIV-SN from 43% to 83% in London, and from 66% to 92% in Johannesburg. In conclusion, a combination of four easily and quickly assessed clinical items can be used to accurately diagnose HIV-SN. DN4-interview used in the context of bilateral feet pain can be used to identify those with neuropathic pain. PMID:27764177
GNSS Spoofing Detection and Mitigation Based on Maximum Likelihood Estimation
Li, Hong; Lu, Mingquan
2017-01-01
Spoofing attacks are threatening the global navigation satellite system (GNSS). The maximum likelihood estimation (MLE)-based positioning technique is a direct positioning method originally developed for multipath rejection and weak signal processing. We find this method also has a potential ability for GNSS anti-spoofing since a spoofing attack that misleads the positioning and timing result will cause distortion to the MLE cost function. Based on the method, an estimation-cancellation approach is presented to detect spoofing attacks and recover the navigation solution. A statistic is derived for spoofing detection with the principle of the generalized likelihood ratio test (GLRT). Then, the MLE cost function is decomposed to further validate whether the navigation solution obtained by MLE-based positioning is formed by consistent signals. Both formulae and simulations are provided to evaluate the anti-spoofing performance. Experiments with recordings in real GNSS spoofing scenarios are also performed to validate the practicability of the approach. Results show that the method works even when the code phase differences between the spoofing and authentic signals are much less than one code chip, which can improve the availability of GNSS service greatly under spoofing attacks. PMID:28665318
GNSS Spoofing Detection and Mitigation Based on Maximum Likelihood Estimation.
Wang, Fei; Li, Hong; Lu, Mingquan
2017-06-30
Spoofing attacks are threatening the global navigation satellite system (GNSS). The maximum likelihood estimation (MLE)-based positioning technique is a direct positioning method originally developed for multipath rejection and weak signal processing. We find this method also has a potential ability for GNSS anti-spoofing since a spoofing attack that misleads the positioning and timing result will cause distortion to the MLE cost function. Based on the method, an estimation-cancellation approach is presented to detect spoofing attacks and recover the navigation solution. A statistic is derived for spoofing detection with the principle of the generalized likelihood ratio test (GLRT). Then, the MLE cost function is decomposed to further validate whether the navigation solution obtained by MLE-based positioning is formed by consistent signals. Both formulae and simulations are provided to evaluate the anti-spoofing performance. Experiments with recordings in real GNSS spoofing scenarios are also performed to validate the practicability of the approach. Results show that the method works even when the code phase differences between the spoofing and authentic signals are much less than one code chip, which can improve the availability of GNSS service greatly under spoofing attacks.
Yiu, Sean; Tom, Brian Dm
2017-01-01
Several researchers have described two-part models with patient-specific stochastic processes for analysing longitudinal semicontinuous data. In theory, such models can offer greater flexibility than the standard two-part model with patient-specific random effects. However, in practice, the high dimensional integrations involved in the marginal likelihood (i.e. integrated over the stochastic processes) significantly complicates model fitting. Thus, non-standard computationally intensive procedures based on simulating the marginal likelihood have so far only been proposed. In this paper, we describe an efficient method of implementation by demonstrating how the high dimensional integrations involved in the marginal likelihood can be computed efficiently. Specifically, by using a property of the multivariate normal distribution and the standard marginal cumulative distribution function identity, we transform the marginal likelihood so that the high dimensional integrations are contained in the cumulative distribution function of a multivariate normal distribution, which can then be efficiently evaluated. Hence, maximum likelihood estimation can be used to obtain parameter estimates and asymptotic standard errors (from the observed information matrix) of model parameters. We describe our proposed efficient implementation procedure for the standard two-part model parameterisation and when it is of interest to directly model the overall marginal mean. The methodology is applied on a psoriatic arthritis data set concerning functional disability.
The Phenomenology and Generation of Positive Mental Imagery in Early Psychosis.
Laing, Jennifer; Morland, Tristan; Fornells-Ambrojo, Miriam
2016-11-01
Theoretical models of depression and bipolar disorder emphasise the importance of positive mental imagery in mood and behaviour. Distressing, intrusive images are common in psychosis; however, little is known about positive imagery experiences or their association with clinical symptoms. The aim of the current study was to examine the phenomenology of positive imagery in early psychosis and the relationship between the characteristics of positive, future-oriented imagery and symptom severity. Characteristics, thematic content and appraisals of recent self-reported images were examined in 31 people with early psychosis. The vividness and perceived likelihood of deliberately generated, future-oriented images were investigated in relation to clinical symptoms. Eighty-four percent of participants reported experiencing a recent positive image. Themes included the achievement of personal goals, spending enjoyable time with peers and family, loving, intimate relationships and escape from current circumstances. The vividness and perceived likelihood of generated prospective imagery were negatively correlated with levels of depression and social anxiety. The relationship between emotional problems and the ability to imagine positive, future events may have implications for motivation, mood and goal-directed behaviour in psychosis. Everyday experiences of positive imagery may represent the simulation of future goals, attempts to cope or avoid aversive experiences or idealised fantasy. Copyright © 2015 John Wiley & Sons, Ltd. The majority of participants experienced a recent positive image with themes related to goal attainment and social relationships. Depression and social anxiety levels were correlated with the vividness of intentionally generated positive future-oriented images and their perceived likelihood. The assessment of positive imagery in early psychosis appears warranted and may provide insights regarding individual coping strategies, values and goals. Copyright © 2015 John Wiley & Sons, Ltd.
Value of circulating cell-free DNA analysis as a diagnostic tool for breast cancer: a meta-analysis
Ma, Xuelei; Zhang, Jing; Hu, Xiuying
2017-01-01
Objectives The aim of this study was to systematically evaluate the diagnostic value of cell free DNA (cfDNA) for breast cancer. Results Among 308 candidate articles, 25 with relevant diagnostic screening qualified for final analysis. The mean sensitivity, specificity and area under the curve (AUC) of SROC plots for 24 studies that distinguished breast cancer patients from healthy controls were 0.70, 0.87, and 0.9314, yielding a DOR of 32.31. When analyzed in subgroups, the 14 quantitative studies produced sensitivity, specificity, AUC, and a DOR of 0.78, 0.83, 0.9116, and 24.40. The 10 qualitative studies produced 0.50, 0.98, 0.9919, and 68.45. For 8 studies that distinguished malignant breast cancer from benign diseases, the specificity, sensitivity, AUC and DOR were 0.75, 0.79, 0.8213, and 9.49. No covariate factors had a significant correlation with relative DOR. Deek's funnel plots indicated an absence of publication bias. Materials and Methods Databases were searched for studies involving the use of cfDNA to diagnose breast cancer. The studies were analyzed to determine sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, diagnostic odds ratio (DOR), and the summary receiver operating characteristic (SROC). Covariates were evaluated for effect on relative DOR. Deek's Funnel plots were generated to measure publication bias. Conclusions Our analysis suggests a promising diagnostic potential of using cfDNA for breast cancer screening, but this diagnostic method is not yet independently sufficient. Further work refining qualitative cfDNA assays will improve the correct diagnosis of breast cancers. PMID:28460452
Dibble, Elizabeth H; Lourenco, Ana P; Baird, Grayson L; Ward, Robert C; Maynard, A Stanley; Mainiero, Martha B
2018-01-01
To compare interobserver variability (IOV), reader confidence, and sensitivity/specificity in detecting architectural distortion (AD) on digital mammography (DM) versus digital breast tomosynthesis (DBT). This IRB-approved, HIPAA-compliant reader study used a counterbalanced experimental design. We searched radiology reports for AD on screening mammograms from 5 March 2012-27 November 2013. Cases were consensus-reviewed. Controls were selected from demographically matched non-AD examinations. Two radiologists and two fellows blinded to outcomes independently reviewed images from two patient groups in two sessions. Readers recorded presence/absence of AD and confidence level. Agreement and differences in confidence and sensitivity/specificity between DBT versus DM and attendings versus fellows were examined using weighted Kappa and generalised mixed modeling, respectively. There were 59 AD patients and 59 controls for 1,888 observations (59 × 2 (cases and controls) × 2 breasts × 2 imaging techniques × 4 readers). For all readers, agreement improved with DBT versus DM (0.61 vs. 0.37). Confidence was higher with DBT, p = .001. DBT achieved higher sensitivity (.59 vs. .32), p < .001; specificity remained high (>.90). DBT achieved higher positive likelihood ratio values, smaller negative likelihood ratio values, and larger ROC values. DBT decreases IOV, increases confidence, and improves sensitivity while maintaining high specificity in detecting AD. • Digital breast tomosynthesis decreases interobserver variability in the detection of architectural distortion. • Digital breast tomosynthesis increases reader confidence in the detection of architectural distortion. • Digital breast tomosynthesis improves sensitivity in the detection of architectural distortion.
Gui, Xuwei; Xiao, Heping
2014-01-01
This systematic review and meta-analysis was performed to determine accuracy and usefulness of adenosine deaminase (ADA) in diagnosis of tuberculosis pleurisy. Medline, Google scholar and Web of Science databases were searched to identify related studies until 2014. Two reviewers independently assessed quality of studies included according to standard Quality Assessment of Diagnosis Accuracy Studies (QUADAS) criteria. The sensitivity, specificity, diagnostic odds ratio and other parameters of ADA in diagnosis of tuberculosis pleurisy were analyzed with Meta-DiSC1.4 software, and pooled using the random effects model. Twelve studies including 865 tuberculosis pleurisy patients and 1379 non-tuberculosis pleurisy subjects were identified from 110 studies for this meta-analysis. The sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR) and diagnosis odds ratio (DOR) of ADA in the diagnosis of tuberculosis pleurisy were 45.25 (95% CI 27.63-74.08), 0.86 (95% CI 0.84-0.88), 0.88 (95% CI 0.86-0.90), 6.32 (95% CI 4.83-8.26) and 0.15 (95% 0.11-0.22), respectively. The area under the summary receiver operating characteristic curve (SROC) was 0.9340. Our results demonstrate that the sensitivity and specificity of ADA are high in the diagnosis of tuberculosis pleurisy especially when ADA≥50 (U/L). Thus, ADA is a relatively sensitive and specific marker for tuberculosis pleurisy diagnosis. However, it is cautious to apply these results due to the heterogeneity in study design of these studies. Further studies are required to confirm the optimal cut-off value of ADA.
Child–Pugh Versus MELD Score for the Assessment of Prognosis in Liver Cirrhosis
Peng, Ying; Qi, Xingshun; Guo, Xiaozhong
2016-01-01
Abstract Child–Pugh and MELD scores have been widely used for the assessment of prognosis in liver cirrhosis. A systematic review and meta-analysis aimed to compare the discriminative ability of Child–Pugh versus MELD score to assess the prognosis of cirrhotic patients. PubMed and EMBASE databases were searched. The statistical results were summarized from every individual study. The summary areas under receiver operating characteristic curves, sensitivities, specificities, positive and negative likelihood ratios, and diagnostic odds ratios were also calculated. Of the 1095 papers initially identified, 119 were eligible for the systematic review. Study population was heterogeneous among studies. They included 269 comparisons, of which 44 favored MELD score, 16 favored Child–Pugh score, 99 did not find any significant difference between them, and 110 did not report the statistical significance. Forty-two papers were further included in the meta-analysis. In patients with acute-on-chronic liver failure, Child–Pugh score had a higher sensitivity and a lower specificity than MELD score. In patients admitted to ICU, MELD score had a smaller negative likelihood ratio and a higher sensitivity than Child–Pugh score. In patients undergoing surgery, Child–Pugh score had a higher specificity than MELD score. In other subgroup analyses, Child–Pugh and MELD scores had statistically similar discriminative abilities or could not be compared due to the presence of significant diagnostic threshold effects. Although Child–Pugh and MELD scores had similar prognostic values in most of cases, their benefits might be heterogeneous in some specific conditions. The indications for Child–Pugh and MELD scores should be further identified. PMID:26937922
How users adopt healthcare information: An empirical study of an online Q&A community.
Jin, Jiahua; Yan, Xiangbin; Li, Yijun; Li, Yumei
2016-02-01
The emergence of social media technology has led to the creation of many online healthcare communities, where patients can easily share and look for healthcare-related information from peers who have experienced a similar problem. However, with increased user-generated content, there is a need to constantly analyse which content should be trusted as one sifts through enormous amounts of healthcare information. This study aims to explore patients' healthcare information seeking behavior in online communities. Based on dual-process theory and the knowledge adoption model, we proposed a healthcare information adoption model for online communities. This model highlights that information quality, emotional support, and source credibility are antecedent variables of adoption likelihood of healthcare information, and competition among repliers and involvement of recipients moderate the relationship between the antecedent variables and adoption likelihood. Empirical data were collected from the healthcare module of China's biggest Q&A community-Baidu Knows. Text mining techniques were adopted to calculate the information quality and emotional support contained in each reply text. A binary logistics regression model and hierarchical regression approach were employed to test the proposed conceptual model. Information quality, emotional support, and source credibility have significant and positive impact on healthcare information adoption likelihood, and among these factors, information quality has the biggest impact on a patient's adoption decision. In addition, competition among repliers and involvement of recipients were tested as moderating effects between these antecedent factors and the adoption likelihood. Results indicate competition among repliers positively moderates the relationship between source credibility and adoption likelihood, and recipients' involvement positively moderates the relationship between information quality, source credibility, and adoption decision. In addition to information quality and source credibility, emotional support has significant positive impact on individuals' healthcare information adoption decisions. Moreover, the relationships between information quality, source credibility, emotional support, and adoption decision are moderated by competition among repliers and involvement of recipients. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.
A controlled trial of automated classification of negation from clinical notes
Elkin, Peter L; Brown, Steven H; Bauer, Brent A; Husser, Casey S; Carruth, William; Bergstrom, Larry R; Wahner-Roedler, Dietlind L
2005-01-01
Background Identification of negation in electronic health records is essential if we are to understand the computable meaning of the records: Our objective is to compare the accuracy of an automated mechanism for assignment of Negation to clinical concepts within a compositional expression with Human Assigned Negation. Also to perform a failure analysis to identify the causes of poorly identified negation (i.e. Missed Conceptual Representation, Inaccurate Conceptual Representation, Missed Negation, Inaccurate identification of Negation). Methods 41 Clinical Documents (Medical Evaluations; sometimes outside of Mayo these are referred to as History and Physical Examinations) were parsed using the Mayo Vocabulary Server Parsing Engine. SNOMED-CT™ was used to provide concept coverage for the clinical concepts in the record. These records resulted in identification of Concepts and textual clues to Negation. These records were reviewed by an independent medical terminologist, and the results were tallied in a spreadsheet. Where questions on the review arose Internal Medicine Faculty were employed to make a final determination. Results SNOMED-CT was used to provide concept coverage of the 14,792 Concepts in 41 Health Records from John's Hopkins University. Of these, 1,823 Concepts were identified as negative by Human review. The sensitivity (Recall) of the assignment of negation was 97.2% (p < 0.001, Pearson Chi-Square test; when compared to a coin flip). The specificity of assignment of negation was 98.8%. The positive likelihood ratio of the negation was 81. The positive predictive value (Precision) was 91.2% Conclusion Automated assignment of negation to concepts identified in health records based on review of the text is feasible and practical. Lexical assignment of negation is a good test of true Negativity as judged by the high sensitivity, specificity and positive likelihood ratio of the test. SNOMED-CT had overall coverage of 88.7% of the concepts being negated. PMID:15876352
Evangelista, Laura; Cuocolo, Alberto; Pace, Leonardo; Mansi, Luigi; Del Vecchio, Silvana; Miletto, Paolo; Sanfilippo, Silvia; Pellegrino, Sara; Guerra, Luca; Pepe, Giovanna; Peluso, Giuseppina; Salvatore, Marco; Galicchio, Rosj; Zuffante, Michele; Annunziata, Salvatore; Farsad, Mohsen; Chiaravalloti, Agostino; Spadafora, Marco
2018-05-07
The aim of this study was to determine the performance of 18 F-FDG-PET/CT in patients with solitary pulmonary nodule (SPN), stratifying the risk according to the likelihood of pulmonary malignancy. FDG-PET/CT of 502 patients, stratified for pre-test cancer risk, were retrospectively analyzed. FDG uptake in SPN was assessed by a 4-point scoring system and semiquantitative analysis using the ratio between SUVmax in SPN and SUVmean in mediastinal blood pool (BP) and between SUVmax in SPN and SUVmean in liver (L). Histopathology and/or follow-up data were used as standard of reference. SPN was malignant in 180 (36%) patients, benign in 175 (35%), and indeterminate in 147 (29%). The 355 patients with a definitive SPN nature (malignant or benign) were considered for the analysis. Considering FDG uptake ≥ 2, sensitivity, specificity, positive (PPV) and negative (NPV) predictive values, and accuracy were 85.6%, 85.7%, 86%, 85.2%, and 85.6% respectively. Sensitivity and PPV were higher (P < 0.05) in intermediate and high-risk patients, while specificity and NPV were higher (P < 0.05) in low-risk patients. On receiver operating characteristic curve analysis, the cut-offs for better discrimination between benign and malignant SPN were 1.56 (sensitivity 81% and specificity 87%) and 1.12 (sensitivity 81% and specificity 86%) for SUVmax/SUVmeanBP and SUVmax/SUVmeanL respectively. In intermediate and high-risk patients, including the SUVmax/SUVmeanBP, the specificity shifted from 85% and 50% to 100%. Visual FDG-PET/CT has an acceptable performance in patients with SPN, but accuracy improves when SUVratios are considered, particularly in patients with intermediate and high risk of malignancy.
Nakagawa, Hitoshi; Nagasaka, Takeshi; Cullings, Harry M; Notohara, Kenji; Hoshijima, Naoko; Young, Joanne; Lynch, Henry T; Tanaka, Noriaki; Matsubara, Nagahide
2009-06-01
It is sometimes difficult to diagnose Lynch syndrome by the simple but strict clinical criteria, or even by the definitive genetic testing for causative germline mutation of mismatch repair genes. Thus, some practical and efficient screening strategy to select highly possible Lynch syndrome patients is exceedingly desirable. We performed a comprehensive study to evaluate the methylation status of whole MLH1 promoter region by direct bisulfite sequencing of the entire MLH1 promoter regions on Lynch and non-Lynch colorectal cancers (CRCs). Then, we established a convenient assay to detect methylation in key CpG islands responsible for the silencing of MLH1 expression. We studied the methylation status of MLH1 as well as the CpG island methylator phenotype (CIMP) and immunohistochemical analysis of mismatch repair proteins on 16 cases of Lynch CRC and 19 cases of sporadic CRCs with high-frequency microsatellite instability (MSI-H). Sensitivity to detect Lynch syndrome by MLH1 (CCAAT) methylation was 88% and the specificity was 84%. Positive likelihood ratio (PLR) was 5.5 and negative likelihood ratio (NLR) was 0.15. Sensitivity by mutational analysis of BRAF was 100%, specificity was 84%, PLR was 6.3 and NLR was zero. By CIMP analysis; sensitivity was 88%, specificity was 79%, PLR was 4.2, and NLR was 0.16. BRAF mutation or MLH1 methylation analysis combined with MSI testing could be a good alternative to screen Lynch syndrome patients in a cost effective manner. Although the assay for CIMP status also showed acceptable sensitivity and specificity, it may not be practical because of its rather complicated assay.
A likelihood ratio anomaly detector for identifying within-perimeter computer network attacks
DOE Office of Scientific and Technical Information (OSTI.GOV)
Grana, Justin; Wolpert, David; Neil, Joshua
The rapid detection of attackers within firewalls of enterprise computer networks is of paramount importance. Anomaly detectors address this problem by quantifying deviations from baseline statistical models of normal network behavior and signaling an intrusion when the observed data deviates significantly from the baseline model. But, many anomaly detectors do not take into account plausible attacker behavior. As a result, anomaly detectors are prone to a large number of false positives due to unusual but benign activity. Our paper first introduces a stochastic model of attacker behavior which is motivated by real world attacker traversal. Then, we develop a likelihoodmore » ratio detector that compares the probability of observed network behavior under normal conditions against the case when an attacker has possibly compromised a subset of hosts within the network. Since the likelihood ratio detector requires integrating over the time each host becomes compromised, we illustrate how to use Monte Carlo methods to compute the requisite integral. We then present Receiver Operating Characteristic (ROC) curves for various network parameterizations that show for any rate of true positives, the rate of false positives for the likelihood ratio detector is no higher than that of a simple anomaly detector and is often lower. Finally, we demonstrate the superiority of the proposed likelihood ratio detector when the network topologies and parameterizations are extracted from real-world networks.« less
A likelihood ratio anomaly detector for identifying within-perimeter computer network attacks
Grana, Justin; Wolpert, David; Neil, Joshua; ...
2016-03-11
The rapid detection of attackers within firewalls of enterprise computer networks is of paramount importance. Anomaly detectors address this problem by quantifying deviations from baseline statistical models of normal network behavior and signaling an intrusion when the observed data deviates significantly from the baseline model. But, many anomaly detectors do not take into account plausible attacker behavior. As a result, anomaly detectors are prone to a large number of false positives due to unusual but benign activity. Our paper first introduces a stochastic model of attacker behavior which is motivated by real world attacker traversal. Then, we develop a likelihoodmore » ratio detector that compares the probability of observed network behavior under normal conditions against the case when an attacker has possibly compromised a subset of hosts within the network. Since the likelihood ratio detector requires integrating over the time each host becomes compromised, we illustrate how to use Monte Carlo methods to compute the requisite integral. We then present Receiver Operating Characteristic (ROC) curves for various network parameterizations that show for any rate of true positives, the rate of false positives for the likelihood ratio detector is no higher than that of a simple anomaly detector and is often lower. Finally, we demonstrate the superiority of the proposed likelihood ratio detector when the network topologies and parameterizations are extracted from real-world networks.« less
Dysfunctional beliefs about symptoms and illness in patients with hypochondriasis.
Weck, Florian; Neng, Julia M B; Richtberg, Samantha; Stangier, Ulrich
2012-01-01
The cognitive model and empirical research underline the importance of dysfunctional beliefs about bodily symptoms and illness in health anxiety and hypochondriasis. However, specificity of such beliefs has not yet been adequately demonstrated for patients with hypochondriasis. This study examined whether dysfunctional beliefs about bodily symptoms and illness are elevated in comparison to patients with anxiety disorders and, therefore, specific for patients with hypochondriasis. Patients with hypochondriasis (n = 38), patients with anxiety disorders (n = 40), and healthy controls (n = 42) completed the Symptom and Outcomes Scale (SOS) measuring participants' estimation of the likelihood of various symptoms being indicative of a particular illness. Additionally, participants' general psychopathology (Brief Symptom Inventory), depressive (Beck Depression Inventory-II), and anxiety symptoms (Beck Anxiety Inventory) were evaluated. In comparison to patients with anxiety disorders and healthy controls, patients with hypochondriasis estimated bodily symptoms to be more likely an indicator for a catastrophic illness. Patients with anxiety disorders took a middle position between patients with hypochondriasis and healthy controls. Regarding the estimation of the likelihood of symptoms indicating a minor illness, no differences were found between the three groups. Dysfunctional beliefs about symptoms and illness are important and specific for patients with hypochondriasis, which is in line with the cognitive model. In order to reduce misinformation about serious illnesses in patients with hypochondriasis, more attention should be paid to psychoeducational strategies. Copyright © 2012 The Academy of Psychosomatic Medicine. Published by Elsevier Inc. All rights reserved.
Balla, Sudheer B; Galic, Ivan; P, Karunakar; Vanin, Stefano; De Luca, Stefano; Cameriere, Roberto
2017-07-01
Deliberate falsification of age was considered to be one of the main reasons for forensic age estimation of the living individuals. This posed to be a challenging task during criminal and legal proceedings, and ultimate care must be taken not to classify juveniles as adults. Third molars are the only developing teeth during late adolescence and early adulthood. Our study was designed to analyze the usefulness of the third molar maturity index (I 3M ) specific cut-off value (I 3M < 0.08) to discriminate adults (≥18 years) and juveniles (<18 years) in South Indian children. 216 panoramic radiographs (114 females and 102 males) of living subjects aged between 14 and 21 years were analyzed. Our results demonstrated high sensitivity (83.3% and 90.2%) and specificity (98.3% and 95.1%) for females and males respectively. The positive likelihood ratios of being adult were 50.00 and 18.35 while the negative likelihood ratios were 0.17 and 0.10 in females and males respectively. The estimated posttest probability was 98.0% in females and 94.8% in males. The obtained results showed that the specific cut-off value of I 3M < 0.08 may be a useful additional tool in discrimination of individuals who are around 18 years of age. Copyright © 2017 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved.
Predictors of specific phobia in children with Williams syndrome.
Pitts, C H; Klein-Tasman, B P; Osborne, J W; Mervis, C B
2016-10-01
Specific phobia (SP) is the most common anxiety disorder among children with Williams syndrome (WS); prevalence rates derived from Diagnostic and Statistical Manual of Mental Disorders-based diagnostic interviews range from 37% to 56%. We evaluated the effects of gender, age, intellectual abilities and/or behaviour regulation difficulties on the likelihood that a child with WS would be diagnosed with SP. A total of 194 6-17 year-olds with WS were evaluated. To best characterise the relations between the predictors and the probability of a SP diagnosis, we explored not only possible linear effects but also curvilinear effects. No gender differences were detected. As age increased, the likelihood of receiving a SP diagnosis decreased. As IQ increased, the probability of receiving a SP diagnosis also decreased. Behaviour regulation difficulties were the strongest predictor of a positive diagnosis. A quadratic relation was detected: The probability of receiving a SP diagnosis gradually rose as behaviour regulation difficulties increased. However, once behaviour regulation difficulties approached the clinical range, the probability of receiving a SP diagnosis asymptoted at a high level. Children with behaviour regulation difficulties in or just below the clinical range were at the greatest risk of developing SP. These findings highlight the value of large samples and the importance of evaluating for nonlinear effects to provide accurate model specification when characterising relations among a dependent variable and possible predictors. © 2016 MENCAP and International Association of the Scientific Study of Intellectual and Developmental Disabilities and John Wiley & Sons Ltd.
Diagnostic value of survivin for malignant pleural effusion: a clinical study and meta-analysis.
Tian, Panwen; Shen, Yongchun; Wan, Chun; Yang, Ting; An, Jing; Yi, Qun; Chen, Lei; Wang, Tao; Wang, Ye; Wen, Fuqiang
2014-01-01
To investigate the diagnostic accuracy of survivin for malignant pleural effusion (MPE). Pleural effusion samples were collected from 40 MPE patients and 45 non-MPE patients. Pleural levels of survivin were measured by ELISA. Literature search was performed in Pubmed and Embase to identify studies regarding the usefulness of survivin to diagnose MPE. Data were retrieved and the pooled sensitivity, specificity and other diagnostic indexes were calculated. The summary receiver operating characteristics (SROC) curve was used to determine the overall diagnostic accuracy. The pleural levels of survivin were higher in MPE patients than non-MPE patients (844.17 ± 358.30 vs. 508.08 ± 169.58 pg/ml, P < 0.05), at a cut-off value of 683.2 pg/ml, the sensitivity and specificity were 57.50% and 88.89%, respectively. A total of six studies were included in present meta-analysis, the overall diagnostic estimates were: sensitivity 0.74 (95% CI: 0.59-0.85); specificity, 0.85 (95% CI: 0.79-0.89); positive likelihood ratio, 4.79 (95% CI: 3.48-6.61); negative likelihood ratio, 0.31 (95% CI: 0.19-0.50), and diagnostic odds ratio, 15.59 (95% CI: 7.69-31.61). The area under SROC curve was 0.86 (95% CI: 0.82-0.89). Our study confirms that the pleural survivin plays a role in the diagnosis of MPE. More studies at a large scale should be performed to validate our findings.
Diagnostic value of KLK6 as an ovarian cancer biomarker: A meta-analysis.
Yang, Fan; Hu, Zhi-DE; Chen, Yingjian; Hu, Cheng-Jin
2016-06-01
Kallikrein-related peptidase 6 (KLK6) is a new potential serum biomarker of ovarian cancer. The aim of the present study was to assess the diagnostic value of KLK6 systematically for ovarian cancer. All the selected studies regarding the changes of KLK6 in ovarian cancer were published prior to April 2015. Five studies involving 485 patients with ovarian cancer, 420 benign cysts and 245 healthy controls met the inclusion criteria. The value of sensitivity, specificity, positive-likelihood ratio (LR+), negative-likelihood ratio (LR-) and area under the receiver operating characteristic curve (ROC) were obtained. All these indices were used to evaluate the diagnostic value of KLK6 for ovarian cancer. The values of sensitivity, specificity, LR+ and LR- (95% confidence interval) of KLK6 were 0.50 (0.47-0.54), 0.91 (0.89-0.93), 7.20 (3.34-15.52) and 0.51 (0.43-0.62), respectively. The area under the summary ROC of KLK6 was 0.86. The index of Q* was 0.79. In conclusion, KLK6 showed high specificity for the diagnosis of ovarian cancer. It can improve the diagnostic accuracy of cancer antigen 125 (CA125). A combined panel of CA125 and KL K6 shows a high diagnostic efficiency for advanced ovarian cancer. Owing to the small number of studies and lack of samples, additional studies meeting the inclusion criteria are required to further analyze the diagnostic value of KLK6 for ovarian cancer.
Clinical signs of impending death in cancer patients.
Hui, David; dos Santos, Renata; Chisholm, Gary; Bansal, Swati; Silva, Thiago Buosi; Kilgore, Kelly; Crovador, Camila Souza; Yu, Xiaoying; Swartz, Michael D; Perez-Cruz, Pedro Emilio; Leite, Raphael de Almeida; Nascimento, Maria Salete de Angelis; Reddy, Suresh; Seriaco, Fabiola; Yennu, Sriram; Paiva, Carlos Eduardo; Dev, Rony; Hall, Stacy; Fajardo, Julieta; Bruera, Eduardo
2014-06-01
The physical signs of impending death have not been well characterized in cancer patients. A better understanding of these signs may improve the ability of clinicians to diagnose impending death. We examined the frequency and onset of 10 bedside physical signs and their diagnostic performance for impending death. We systematically documented 10 physical signs every 12 hours from admission to death or discharge in 357 consecutive patients with advanced cancer admitted to two acute palliative care units. We examined the frequency and median onset of each sign from death backward and calculated their likelihood ratios (LRs) associated with death within 3 days. In total, 203 of 357 patients (52 of 151 in the U.S., 151 of 206 in Brazil) died. Decreased level of consciousness, Palliative Performance Scale ≤20%, and dysphagia of liquids appeared at high frequency and >3 days before death and had low specificity (<90%) and positive LR (<5) for impending death. In contrast, apnea periods, Cheyne-Stokes breathing, death rattle, peripheral cyanosis, pulselessness of radial artery, respiration with mandibular movement, and decreased urine output occurred mostly in the last 3 days of life and at lower frequency. Five of these signs had high specificity (>95%) and positive LRs for death within 3 days, including pulselessness of radial artery (positive LR: 15.6; 95% confidence interval [CI]: 13.7-17.4), respiration with mandibular movement (positive LR: 10; 95% CI: 9.1-10.9), decreased urine output (positive LR: 15.2; 95% CI: 13.4-17.1), Cheyne-Stokes breathing (positive LR: 12.4; 95% CI: 10.8-13.9), and death rattle (positive LR: 9; 95% CI: 8.1-9.8). We identified highly specific physical signs associated with death within 3 days among cancer patients. ©AlphaMed Press.
ERIC Educational Resources Information Center
Sprinkle, Rose; Hunt, Stephen; Simonds, Cheri; Comadena, Mark
2006-01-01
This study examined the impact of teachers' use of fear appeals and efficacy statements on student affective learning, motivation, likelihood of taking a course with the instructor, and likelihood of visiting with the instructor for help. The results suggest that fear and efficacy interact to more positively influence students' perceptions of…
Adult Age Differences in Frequency Estimations of Happy and Angry Faces
ERIC Educational Resources Information Center
Nikitin, Jana; Freund, Alexandra M.
2015-01-01
With increasing age, the ratio of gains to losses becomes more negative, which is reflected in expectations that positive events occur with a high likelihood in young adulthood, whereas negative events occur with a high likelihood in old age. Little is known about expectations of social events. Given that younger adults are motivated to establish…
Holt, Martin; Lee, Evelyn; Prestage, Garrett P; Zablotska, Iryna; de Wit, John; Mao, Limin
2013-01-01
To assess the changing health promotion needs of human immunodeficiency virus (HIV)-positive gay men in Australia, we analysed the social and behavioural characteristics of HIV-positive men in the Australian Gay Community Periodic Surveys. We looked at change over time in the characteristics of HIV-positive men (from 2000-2001 to 2008-2009) and compared HIV-positive men with their HIV-negative peers within each time period. Multivariate logistic regression analysis was used to assess independent changes over time within each HIV status group. A total of 21,620 responses were included in the analyses; 10,537 in 2000-2001 and 11,083 in 2008-2009. Between the two time periods, HIV-positive and HIV-negative men became more similar in the following areas: paid employment, sexual identity, number of male sex partners, the likelihood of having a regular male partner and having a seroconcordant regular male partner. The two groups diverged in these areas: age, ethnicity, educational level, social engagement with gay men, types of relationship with regular male partners, likelihood of unprotected anal intercourse with casual male partners and likelihood of HIV disclosure to casual male partners. Workforce participation and educational attainment have improved among HIV-positive gay men since 2000, but they still lag behind their HIV-negative peers in these areas. Because HIV-positive men are an ageing cohort, support services will need to increasingly address issues of HIV, sexuality and ageing with HIV-positive men. The increase in unprotected anal intercourse and HIV disclosure with casual partners means that education and support services will increasingly need to address effective HIV disclosure and non-condom-based risk reduction strategies with both HIV-positive and HIV-negative gay men.
NASA Astrophysics Data System (ADS)
Barkley, Brett E.
A cooperative detection and tracking algorithm for multiple targets constrained to a road network is presented for fixed-wing Unmanned Air Vehicles (UAVs) with a finite field of view. Road networks of interest are formed into graphs with nodes that indicate the target likelihood ratio (before detection) and position probability (after detection). A Bayesian likelihood ratio tracker recursively assimilates target observations until the cumulative observations at a particular location pass a detection criterion. At this point, a target is considered detected and a position probability is generated for the target on the graph. Data association is subsequently used to route future measurements to update the likelihood ratio tracker (for undetected target) or to update a position probability (a previously detected target). Three strategies for motion planning of UAVs are proposed to balance searching for new targets with tracking known targets for a variety of scenarios. Performance was tested in Monte Carlo simulations for a variety of mission parameters, including tracking on road networks with varying complexity and using UAVs at various altitudes.
Reid, S; Lu, C; Hardy, N; Casikar, I; Reid, G; Cario, G; Chou, D; Almashat, D; Condous, G
2014-12-01
To use office gel sonovaginography (SVG) to predict posterior deep infiltrating endometriosis (DIE) in women undergoing laparoscopy. This was a multicenter prospective observational study carried out between January 2009 and February 2013. All women were of reproductive age, had a history of chronic pelvic pain and underwent office gel SVG assessment for the prediction of posterior compartment DIE prior to laparoscopic endometriosis surgery. Gel SVG findings were compared with laparoscopic findings to determine the diagnostic accuracy of office gel SVG for the prediction of posterior compartment DIE. In total, 189 women underwent preoperative gel SVG and laparoscopy for endometriosis. At laparoscopy, 57 (30%) women had posterior DIE and 43 (23%) had rectosigmoid/anterior rectal DIE. For the prediction of rectosigmoid/anterior rectal (i.e. bowel) DIE, gel SVG had an accuracy of 92%, sensitivity of 88%, specificity of 93%, positive predictive value (PPV) of 79%, negative predictive value (NPV) of 97%, positive likelihood ratio (LR+) of 12.9 and negative likelihood ratio (LR-) of 0.12 (P = 3.98E-25); for posterior vaginal wall and rectovaginal septum (RVS) DIE, respectively, the accuracy was 95% and 95%, sensitivity was 18% and 18%, specificity was 99% and 100%, PPV was 67% and 100%, NPV was 95% and 95%, LR+ was 32.4 and infinity and LR- was 0.82 and 0.82 (P = 0.009 and P = 0.003). Office gel SVG appears to be an effective outpatient imaging technique for the prediction of bowel DIE, with a higher accuracy for the prediction of rectosigmoid compared with anterior rectal DIE. Although the sensitivity for vaginal and RVS DIE was limited, gel SVG had a high specificity and NPV for all forms of posterior DIE, indicating that a negative gel SVG examination is highly suggestive of the absence of DIE at laparoscopy. Copyright © 2014 ISUOG. Published by John Wiley & Sons Ltd.
Armeli, Stephen; O'Hara, Ross E; Ehrenberg, Ethan; Sullivan, Tami P; Tennen, Howard
2014-09-01
The goal of the present study was to examine whether within-person, episode-specific changes in drinking-to-cope (DTC) motivation from the previous evening were associated with concurrent daily mood and fatigue-related symptoms among college student drinkers (N = 1,421; 54% female). We conducted an Internet-based daily diary study in which students reported over 30 days on their previous night's drinking level and motivation and their current mood (i.e., sadness, anxiety, anger/hostility, and positive mood) and fatigue-related symptoms. Hypotheses were tested using hierarchical linear models in which the current day's outcome was predicted by last night's levels of DTC motivation and drinking, controlling for drinking to enhance motivation, sex, current day's physical symptoms and drinking, and yesterday's level of the outcome. Subsequent models also predicted outcomes 2 days following the drinking event. Relative increases in previous night's DTC motivation were associated with higher levels of current day negative mood and fatigue-related symptoms and lower levels of positive mood. Also, the association between episode-specific DTC motivation and negative mood was stronger in the positive direction when individuals reported higher levels of nonsocial drinking from the previous night. Last, episode-specific DTC showed similar associations with sadness and anger/hostility 2 days after the drinking event. The results are generally consistent with the posited attention allocation and ego-depletion mechanisms. Findings suggest that the deleterious effects of repeated episodes of DTC, over time, could help to explain the increased likelihood of alcohol-related problems seen in prior studies.
Tang, Jian.; Chen, Yuwei.; Jaakkola, Anttoni.; Liu, Jinbing.; Hyyppä, Juha.; Hyyppä, Hannu.
2014-01-01
Laser scan matching with grid-based maps is a promising tool for real-time indoor positioning of mobile Unmanned Ground Vehicles (UGVs). While there are critical implementation problems, such as the ability to estimate the position by sensing the unknown indoor environment with sufficient accuracy and low enough latency for stable vehicle control, further development work is necessary. Unfortunately, most of the existing methods employ heuristics for quick positioning in which numerous accumulated errors easily lead to loss of positioning accuracy. This severely restricts its applications in large areas and over lengthy periods of time. This paper introduces an efficient real-time mobile UGV indoor positioning system for large-area applications using laser scan matching with an improved probabilistically-motivated Maximum Likelihood Estimation (IMLE) algorithm, which is based on a multi-resolution patch-divided grid likelihood map. Compared with traditional methods, the improvements embodied in IMLE include: (a) Iterative Closed Point (ICP) preprocessing, which adaptively decreases the search scope; (b) a totally brute search matching method on multi-resolution map layers, based on the likelihood value between current laser scan and the grid map within refined search scope, adopted to obtain the global optimum position at each scan matching; and (c) a patch-divided likelihood map supporting a large indoor area. A UGV platform called NAVIS was designed, manufactured, and tested based on a low-cost robot integrating a LiDAR and an odometer sensor to verify the IMLE algorithm. A series of experiments based on simulated data and field tests with NAVIS proved that the proposed IMEL algorithm is a better way to perform local scan matching that can offer a quick and stable positioning solution with high accuracy so it can be part of a large area localization/mapping, application. The NAVIS platform can reach an updating rate of 12 Hz in a feature-rich environment and 2 Hz even in a feature-poor environment, respectively. Therefore, it can be utilized in a real-time application. PMID:24999715
Tang, Jian; Chen, Yuwei; Jaakkola, Anttoni; Liu, Jinbing; Hyyppä, Juha; Hyyppä, Hannu
2014-07-04
Laser scan matching with grid-based maps is a promising tool for real-time indoor positioning of mobile Unmanned Ground Vehicles (UGVs). While there are critical implementation problems, such as the ability to estimate the position by sensing the unknown indoor environment with sufficient accuracy and low enough latency for stable vehicle control, further development work is necessary. Unfortunately, most of the existing methods employ heuristics for quick positioning in which numerous accumulated errors easily lead to loss of positioning accuracy. This severely restricts its applications in large areas and over lengthy periods of time. This paper introduces an efficient real-time mobile UGV indoor positioning system for large-area applications using laser scan matching with an improved probabilistically-motivated Maximum Likelihood Estimation (IMLE) algorithm, which is based on a multi-resolution patch-divided grid likelihood map. Compared with traditional methods, the improvements embodied in IMLE include: (a) Iterative Closed Point (ICP) preprocessing, which adaptively decreases the search scope; (b) a totally brute search matching method on multi-resolution map layers, based on the likelihood value between current laser scan and the grid map within refined search scope, adopted to obtain the global optimum position at each scan matching; and (c) a patch-divided likelihood map supporting a large indoor area. A UGV platform called NAVIS was designed, manufactured, and tested based on a low-cost robot integrating a LiDAR and an odometer sensor to verify the IMLE algorithm. A series of experiments based on simulated data and field tests with NAVIS proved that the proposed IMEL algorithm is a better way to perform local scan matching that can offer a quick and stable positioning solution with high accuracy so it can be part of a large area localization/mapping, application. The NAVIS platform can reach an updating rate of 12 Hz in a feature-rich environment and 2 Hz even in a feature-poor environment, respectively. Therefore, it can be utilized in a real-time application.
Individual, team, and coach predictors of players' likelihood to aggress in youth soccer.
Chow, Graig M; Murray, Kristen E; Feltz, Deborah L
2009-08-01
The purpose of this study was to examine personal and socioenvironmental factors of players' likelihood to aggress. Participants were youth soccer players (N = 258) and their coaches (N = 23) from high school and club teams. Players completed the Judgments About Moral Behavior in Youth Sports Questionnaire (JAMBYSQ; Stephens, Bredemeier, & Shields, 1997), which assessed athletes' stage of moral development, team norm for aggression, and self-described likelihood to aggress against an opponent. Coaches were administered the Coaching Efficacy Scale (CES; Feltz, Chase, Moritz, & Sullivan, 1999). Using multilevel modeling, results demonstrated that the team norm for aggression at the athlete and team level were significant predictors of athletes' self likelihood to aggress scores. Further, coaches' game strategy efficacy emerged as a positive predictor of their players' self-described likelihood to aggress. The findings contribute to previous research examining the socioenvironmental predictors of athletic aggression in youth sport by demonstrating the importance of coaching efficacy beliefs.
Conde, Esther; Suárez-Gauthier, Ana; Benito, Amparo; Garrido, Pilar; García-Campelo, Rosario; Biscuola, Michele; Paz-Ares, Luis; Hardisson, David; de Castro, Javier; Camacho, M. Carmen; Rodriguez-Abreu, Delvys; Abdulkader, Ihab; Ramirez, Josep; Reguart, Noemí; Salido, Marta; Pijuán, Lara; Arriola, Edurne; Sanz, Julián; Folgueras, Victoria; Villanueva, Noemí; Gómez-Román, Javier; Hidalgo, Manuel; López-Ríos, Fernando
2014-01-01
Background Based on the excellent results of the clinical trials with ALK-inhibitors, the importance of accurately identifying ALK positive lung cancer has never been greater. However, there are increasing number of recent publications addressing discordances between FISH and IHC. The controversy is further fuelled by the different regulatory approvals. This situation prompted us to investigate two ALK IHC antibodies (using a novel ultrasensitive detection-amplification kit) and an automated ALK FISH scanning system (FDA-cleared) in a series of non-small cell lung cancer tumor samples. Methods Forty-seven ALK FISH-positive and 56 ALK FISH-negative NSCLC samples were studied. All specimens were screened for ALK expression by two IHC antibodies (clone 5A4 from Novocastra and clone D5F3 from Ventana) and for ALK rearrangement by FISH (Vysis ALK FISH break-apart kit), which was automatically captured and scored by using Bioview's automated scanning system. Results All positive cases with the IHC antibodies were FISH-positive. There was only one IHC-negative case with both antibodies which showed a FISH-positive result. The overall sensitivity and specificity of the IHC in comparison with FISH were 98% and 100%, respectively. Conclusions The specificity of these ultrasensitive IHC assays may obviate the need for FISH confirmation in positive IHC cases. However, the likelihood of false negative IHC results strengthens the case for FISH testing, at least in some situations. PMID:25248157
Work-related injury factors and safety climate perception in truck drivers.
Anderson, Naomi J; Smith, Caroline K; Byrd, Jesse L
2017-08-01
The trucking industry has a high burden of work-related injuries. This study examined factors, such as safety climate perceptions, that may impact injury risk. A random sample of 9800 commercial driver's license holders (CDL) were sent surveys, only 4360 were eligible truck drivers. Descriptive statistics and logistic regression models were developed to describe the population and identify variables associated with work-related injury. 2189 drivers completed the pertinent interview questions. Driving less-than-truckload, daytime sleepiness, pressure to work faster, and having a poor composite score for safety perceptions were all associated with increased likelihood of work-related injury. Positive safety perception score was protective for odds of work-related injury, and increased claim filing when injured. Positive psychological safety climate is associated with decreased likelihood of work-related injury and increased likelihood that a driver injured on the job files a workers' compensation claim. © 2017 Wiley Periodicals, Inc.
Min, Qinghua; Shao, Kangwei; Zhai, Lulan; Liu, Wei; Zhu, Caisong; Yuan, Lixin; Yang, Jun
2015-02-07
Diffusion-weighted magnetic resonance imaging (DW-MRI) is different from conventional diagnostic methods and has the potential to delineate the microscopic anatomy of a target tissue or organ. The purpose of our study was to evaluate the value of DW-MRI in the diagnosis of benign and malignant breast masses, which would help the clinical surgeon to decide the scope and pattern of operation. A total of 52 female patients with palpable solid breast masses received breast MRI scans using routine sequences, dynamic contrast-enhanced imaging, and diffusion-weighted echo-planar imaging at b values of 400, 600, and 800 s/mm(2), respectively. Two regions of interest (ROIs) were plotted, with a smaller ROI for the highest signal and a larger ROI for the overall lesion. Apparent diffusion coefficient (ADC) values were calculated at three different b values for all detectable lesions and from two different ROIs. The sensitivity, specificity, positive predictive value, and positive likelihood ratio of DW-MRI were determined for comparison with histological results. A total of 49 (49/52, 94.2%) lesions were detected using DW-MRI, including 20 benign lesions (two lesions detected in the same patient) and 29 malignant lesions. Benign lesion had a higher mean ADC value than their malignant counterparts, regardless of b value. According to the receiver operating characteristic (ROC) curve, the smaller-range ROI was more effective in differentiation between benign and malignant lesions. The area under the ROC curve was the largest at a b value of 800 s/mm(2). With a threshold ADC value at 1.23 × 10(-3) mm(2)/s, DW-MRI achieved a sensitivity of 82.8%, specificity of 90.0%, positive predictive value of 92.3%, and positive likelihood ratio of 8.3 for differentiating benign and malignant lesions. DW-MRI is an accurate diagnostic tool for differentiation between benign and malignant breast lesions, with an optimal b value of 800 s/mm(2). A smaller-range ROI focusing on the highest signal has a better differential value.
Diagnostic capability of spectral-domain optical coherence tomography for glaucoma.
Wu, Huijuan; de Boer, Johannes F; Chen, Teresa C
2012-05-01
To determine the diagnostic capability of spectral-domain optical coherence tomography in glaucoma patients with visual field defects. Prospective, cross-sectional study. Participants were recruited from a university hospital clinic. One eye of 85 normal subjects and 61 glaucoma patients with average visual field mean deviation of -9.61 ± 8.76 dB was selected randomly for the study. A subgroup of the glaucoma patients with early visual field defects was calculated separately. Spectralis optical coherence tomography (Heidelberg Engineering, Inc) circular scans were performed to obtain peripapillary retinal nerve fiber layer (RNFL) thicknesses. The RNFL diagnostic parameters based on the normative database were used alone or in combination for identifying glaucomatous RNFL thinning. To evaluate diagnostic performance, calculations included areas under the receiver operating characteristic curve, sensitivity, specificity, positive predictive value, negative predictive value, positive likelihood ratio, and negative likelihood ratio. Overall RNFL thickness had the highest area under the receiver operating characteristic curve values: 0.952 for all patients and 0.895 for the early glaucoma subgroup. For all patients, the highest sensitivity (98.4%; 95% confidence interval, 96.3% to 100%) was achieved by using 2 criteria: ≥ 1 RNFL sectors being abnormal at the < 5% level and overall classification of borderline or outside normal limits, with specificities of 88.9% (95% confidence interval, 84.0% to 94.0%) and 87.1% (95% confidence interval, 81.6% to 92.5%), respectively, for these 2 criteria. Statistical parameters for evaluating the diagnostic performance of the Spectralis spectral-domain optical coherence tomography were good for early perimetric glaucoma and were excellent for moderately advanced perimetric glaucoma. Copyright © 2012 Elsevier Inc. All rights reserved.
Clinical performance of a new point-of-care cardiac troponin I test.
Christ, Michael; Geier, Felicitas; Blaschke, Sabine; Giannitsis, Evangelos; Khellaf, Mehdi; Mair, Johannes; Pariente, David; Scharnhorst, Volkher; Semjonow, Veronique; Hausfater, Pierre
2018-04-09
We evaluated the clinical performance of the Minicare cardiac troponin-I (cTnI), a new point-of-care (POC) cTnI test for the diagnosis of acute myocardial infarction (AMI) in a prospective, multicentre study (ISRCTN77371338). Of 474 patients (≥18 years) admitted to an emergency department (ED) or chest pain unit (CPU) with symptoms suggestive of acute coronary syndrome (ACS; ≤12 h from symptom onset), 465 were eligible. Minicare cTnI was tested immediately, 3 h and 6 h after presentation. AMI diagnoses were adjudicated independently based on current guidelines. The diagnostic performance of the Minicare cTnI test at 3 h was similar for whole blood and in plasma: sensitivity 0.92 vs. 0.90; specificity 0.91 vs. 0.90; positive predictive value (PPV) 0.68 vs. 0.66; negative predictive value (NPV) 0.98 vs. 0.98; positive likelihood ratio (LR+) 10.18 vs. 9.41; negative likelihood ratio (LR-) 0.09 vs. 0.11. The optimal diagnostic performance was obtained at 3 h using cut-offs cTnI >43 ng/L plus cTnI change from admission ≥18.5 ng/L: sensitivity 0.90, specificity 0.96, PPV 0.81, NPV 0.98, and LR+ 21.54. The area under the receiver operating characteristics (ROC) curve for cTnI whole blood baseline value and absolute change after 3 h curve was 0.93. These data support the clinical usefulness of Minicare cTnI within a 0 h/3 h-blood sampling protocol supported by current guidelines for the evaluation of suspected ACS.
Sharp, Adam L; Jones, Jason P; Wu, Ivan; Huynh, Dan; Kocher, Keith E; Shah, Nirav R; Gould, Michael K
2016-04-01
Pneumonia severity tools were primarily developed in cohorts of hospitalized patients, limiting their applicability to the emergency department (ED). We describe current community ED admission practices and examine the accuracy of the CURB-65 to predict 30-day mortality for patients, either discharged or admitted with community-acquired pneumonia (CAP). A retrospective, observational study of adult CAP encounters in 14 community EDs within an integrated healthcare system. We calculated CURB-65 scores for all encounters and described the use of hospitalization, stratified by each score (0-5). We then used each score as a cutoff to calculate sensitivity, specificity, positive predictive value, negative predictive value (NPV), positive likelihood ratios, and negative likelihood ratios for predicting 30-day mortality. The sample included 21,183 ED encounters for CAP (7,952 discharged and 13,231 admitted). The C-statistic describing the accuracy of CURB-65 for predicting 30-day mortality in the full sample was 0.761 (95% confidence interval [CI], 0.747-0.774). The C-statistic was 0.864 (95% CI, 0.821-0.906) among patients discharged from the ED compared with 0.689 (95% CI, 0.672-0.705) among patients who were admitted. Among all ED encounters a CURB-65 threshold of ≥1 was 92.8% sensitive and 38.0% specific for predicting mortality, with a 99.9% NPV. Among all encounters, 62.5% were admitted, including 36.2% of those at lowest risk (CURB-65 = 0). CURB-65 had very good accuracy for predicting 30-day mortality among patients discharged from the ED. This severity tool may help ED providers risk stratify patients to assist with disposition decisions and identify unwarranted variation in patient care. © 2016 by the Society for Academic Emergency Medicine.
McGuire, Connor; Kristman, Vicki L; Shaw, William; Williams-Whitt, Kelly; Reguly, Paula; Soklaridis, Sophie
2015-09-01
To determine the association between supervisors' leadership style and autonomy and supervisors' likelihood of supporting job accommodations for back-injured workers. A cross-sectional study of supervisors from Canadian and US employers was conducted using a web-based, self-report questionnaire that included a case vignette of a back-injured worker. Autonomy and two dimensions of leadership style (considerate and initiating structure) were included as exposures. The outcome, supervisors' likeliness to support job accommodation, was measured with the Job Accommodation Scale (JAS). We conducted univariate analyses of all variables and bivariate analyses of the JAS score with each exposure and potential confounding factor. We used multivariable generalized linear models to control for confounding factors. A total of 796 supervisors participated. Considerate leadership style (β = .012; 95% CI .009-.016) and autonomy (β = .066; 95% CI .025-.11) were positively associated with supervisors' likelihood to accommodate after adjusting for appropriate confounding factors. An initiating structure leadership style was not significantly associated with supervisors' likelihood to accommodate (β = .0018; 95% CI -.0026 to .0061) after adjusting for appropriate confounders. Autonomy and a considerate leadership style were positively associated with supervisors' likelihood to accommodate a back-injured worker. Providing supervisors with more autonomy over decisions of accommodation and developing their considerate leadership style may aid in increasing work accommodation for back-injured workers and preventing prolonged work disability.
Braga, Daniela Paes Almeida Ferreira; Halpern, Gabriela; Setti, Amanda S; Figueira, Rita Cássia S; Iaconelli, Assumpto; Borges, Edson
2015-07-01
The aim of this study was to evaluate the influence of patients' lifestyle factors and eating habits on embryo development. A total of 2659 embryos recovered from 269 patients undergoing intracytoplasmic sperm injection cycles were included. The frequency of intake of food items and social habits were registered and its influences on embryo development evaluated. The consumption of cereals, vegetables and fruits positively influenced the embryo quality at the cleavage stage. The quality of the embryo at the cleavage stage was also negatively correlated with the consumption of alcoholic drinks and smoking habits. The consumption of fruits influenced the likelihood of blastocyst formation, which was also positively affected by the consumption of fish. Being on a weight-loss diet and consumption of red meat had a negative influence on the likelihood of blastocyst formation. The likelihood of blastocyst formation was also negatively influenced by the consumption of alcoholic drinks and by smoking habits. The consumption of red meat and body mass index had a negative effect on the implantation rate and the likelihood of pregnancy. In addition, being on a weight-loss diet had a negative influence on implantation rate. Our evidence suggests a possible relationship between environmental factors and ovary biology. Copyright © 2015 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.
NASA Technical Reports Server (NTRS)
Battin, R. H.; Croopnick, S. R.; Edwards, J. A.
1977-01-01
The formulation of a recursive maximum likelihood navigation system employing reference position and velocity vectors as state variables is presented. Convenient forms of the required variational equations of motion are developed together with an explicit form of the associated state transition matrix needed to refer measurement data from the measurement time to the epoch time. Computational advantages accrue from this design in that the usual forward extrapolation of the covariance matrix of estimation errors can be avoided without incurring unacceptable system errors. Simulation data for earth orbiting satellites are provided to substantiate this assertion.
College students' responses to content-specific advisories regarding television and movies.
Bahk, C M
2000-08-01
Extending Ingold's research on adult viewers' responses to mature content advisories, this study examined the likelihood of viewing television programs and of viewing theatrical movies with general and content-specific advisories. The results show that among the 63 undergraduate men, viewing likelihood was increased significantly with the provision of all types of mature content advisories, whereas among the 122 undergraduate women viewing interest increased with the 'sexuality' advisory but decreased with the 'violence' advisory.
Improvement in likelihood to donate blood after being offered a topical anesthetic.
Watanabe, Kyle M; Jay, Jeffrey; Alicto, Christopher; Yamamoto, Loren G
2011-02-01
While there are many reasons people choose not to donate blood, pain sustained during the venipuncture portion of the blood donation process is likely one deterrent to volunteer donation. The purpose of this study was to survey the improvement in likelihood of donation if participants were given the option of a topical anesthetic cream prior to venipuncture. Over a three month period 316 adults (convenience sample) completed a one page survey consisting of twelve questions pertaining to blood donation. Participants were asked about their likelihood of donating blood in the near future (No Possibility, Possible, Likely, Certain). They were then informed of the possibility of using a topical anesthetic cream prior to donation. Subsequently, their likelihood of donating blood was reassessed. Fifty (16%) subjects reported an increased likelihood of donating blood if offered a topical anesthetic (p〈0.0001). Of these respondents reporting an increase in donation likelihood, eleven improved by 2 or more likelihood categories. Amongst the 169 participants who never donated blood, 34 (20%) reported an increased likelihood of donation after being told about the topical anesthetic cream, compared to 16 (10%) of the 147 subjects who had previously donated blood (p=0.02). The findings of this study suggest that providing a topical anesthetic had a positive effect on the study participants' likelihood of donating blood. This improvement was greater amongst those who have never donated blood. Hawaii Medical Journal Copyright 2011.
Anthropometrics of Italian Senior Male Rugby Union Players: From Elite to Second Division.
Fontana, Federico Y; Colosio, Alessandro; De Roia, Gabriela F; Da Lozzo, Giorgio; Pogliaghi, Silvia
2015-09-01
Anthropometric evaluation of athletes is necessary to optimize talent identification and player development. To provide a specific anthropometric reference database of senior male rugby players competing at different levels in the southern European region. Cross-sectional. In 362 professional players (25 ± 4 y; 138 Italian national team, 97 first-division, and 127 second-division national championships) the authors measured mass, stature, and percentage body fat (plicometry). Mean, SD, and coefficient of variation were calculated for forwards and backs and for positional subgroups. Binomial logistic regression and receiver-operating-characteristic curve were performed to assess which variables best predicted level assignment (international vs national level). For all competitive levels forwards were significantly heavier and taller and had a larger percentage body fat and fat-free mass than backs. The lower the competitive level, the higher the within-role variability observed; furthermore, players in a specific positional subgroup were lighter, shorter, and fatter and had less fat-free mass. Fatfree mass is the variable that best predicts the likelihood of being classified as an international or national player (cutoff value 79.54 kg). The data confirm the specificity in the physical requirements of rugby in individual playing positions at all competitive levels and document significant differences among elite and 1st- and 2nd-division players in the same positional role. These differences may reflect the variable technical abilities, selection, training practices, and requirements of the game among these categories.
Tissue preservation with mass spectroscopic analysis: Implications for cancer diagnostics.
Hall, O Morgan; Peer, Cody J; Figg, William D
2018-05-17
Surgical intervention is a common treatment modality for localized cancer. Post-operative analysis involves evaluation of surgical margins to assess whether all malignant tissue has been resected because positive surgical margins lead to a greater likelihood of recurrence. Secondary treatments are utilized to minimize the negative effects of positive surgical margins. Recently, in Science Translational Medicine, Zhang et al describe a new mass spectroscopic technique that could potentially decrease the likelihood of positive surgical margins. Their nondestructive in vivo tissue sampling leads to a highly accurate and rapid cancer diagnosis with great precision between healthy and malignant tissue. This new tool has the potential to improve surgical margins and accelerate cancer diagnostics by analyzing biomolecular signatures of various tissues and diseases.
Smoking relapse situations among a community-recruited sample of Spanish daily smokers.
Piñeiro, Bárbara; López-Durán, Ana; Martínez-Vispo, Carmela; Fernández Del Río, Elena; Martínez, Úrsula; Rodríguez-Cano, Rubén; Míguez, M Carmen; Becoña, Elisardo
2017-12-01
Relapse is a common factor within the behavior change process. However, there is scarce and limited knowledge of smoking relapse situations in population-based samples. The aim of this study was to identify smoking relapse situations among a sample of Spanish relapsers from the general population. A sample of 775 relapsers was recruited among the general population using a snowball method. Participants completed a survey including sociodemographic, smoking-related and psychopathology variables. Smoking relapse situations were identified through specific questions assessing different aspects related to the last relapse episode. The majority of smoking relapse situations were attributed to positive affect (36.6%) and negative affect (34.3%), followed by lack of control (10.1%), smoking habit (6.7%), craving or nicotine withdrawal (6.3%), and social pressure (5.9%). Being unemployed and having a mental disorder in the past increased the likelihood of relapse in situations of negative affect. Being single and having quit smoking to save money were associated with an increased likelihood of relapse in situations of positive affect. Affect plays a significant role in smoking relapse among a community sample of unassisted Spanish smokers. Relapse may be much more of an affective and situational process than a habit, physiological or social pressure. Findings from this study may help develop tailored community smoking relapse prevention strategies or programs. Copyright © 2017 Elsevier Ltd. All rights reserved.
Diagnostic value of clinical tests for degenerative rotator cuff disease in medical practice.
Lasbleiz, S; Quintero, N; Ea, K; Petrover, D; Aout, M; Laredo, J D; Vicaut, E; Bardin, T; Orcel, P; Beaudreuil, J
2014-06-01
To assess the diagnostic value of clinical tests for degenerative rotator cuff disease (DRCD) in medical practice. Patients with DRCD were prospectively included. Eleven clinical tests of the rotator cuff have been done. One radiologist performed ultrasonography (US) of the shoulder. Results of US were expressed as normal tendon, tendinopathy or full-thickness tear (the reference). For each clinical test and each US criteria, sensitivity, specificity, negative predictive value and positive predictive value, accuracy, negative likelihood ratio (NLR) and positive likelihood ratio (PLR) were calculated. Clinical relevance was defined as PLR ≥2 and NLR ≤0.5. For 35 patients (39 shoulders), Jobe (PLR: 2.08, NLR: 0.31) and full-can (2, 0.5) test results were relevant for diagnosis of supraspinatus tears and resisted lateral rotation (2.42, 0.5) for infraspinatus tears, with weakness as response criteria. The lift-off test (8.50, 0.27) was relevant for subscapularis tears with lag sign as response criteria. Yergason's test (3.7, 0.41) was relevant for tendinopathy of the long head of the biceps with pain as a response criterion. There was no relevant clinical test for diagnosis of tendinopathy of supraspinatus, infraspinatus or subscapularis. Five of 11 clinical tests were relevant for degenerative rotator cuff disease. Copyright © 2014 Elsevier Masson SAS. All rights reserved.
Dalla Nora, Magali; Hörner, Rosmari; De Carli, Diego Michelon; Rocha, Marta Pires da; Araujo, Amanda Faria de; Fagundes, Renato Borges
2016-01-01
The diagnosis of H. pylori infection can be performed by non-invasive and invasive methods.The identification through a fecal antigen test is a non-invasive, simple, and relatively inexpensive test. To determine the diagnostic performance of fecal antigen test in the identification of H. pylori infection. H. pylori antigens were identified in the stools of dyspeptic patients undergoing upper gastrointestinal endoscopy. For the identification of H. pylori antigen, we use ImmunoCard STAT! HpSA with immunochromatography technique. Histopathology plus urease test were the gold standard. We studied 163 patients, 51% male, mean age of 56.7± 8.5years. H. pylori infection was present in 49%. Fecal test presented: sensitivity 67.5% (CI95% 60.6-72.9); specificity 85.5% (CI95% 78.9-90.7); positive predictive value 81.8% (CI95% 73.4-88.4) and negative predictive value 73,2% (CI95% 67.5-77.6); Positive likelihood ratio was 4.7 (CI95% 2.9-7.9) and Negative Likelihood Ratio 0.4 (CI95% 0.3-0.5). The prevalence odds ratio for a positive test was 12.3 (CI95% 5.7-26.3).The index kappa between FAT and histology/urease test was 0.53 (CI95% 0.39-0.64). Immunochromatographic FAT is less expensive than the other methods and readily accepted by the patients but its diagnostic performance does not recommend its use in the primary diagnosis, when the patient may have an active infection.
Is it possible to predict office hysteroscopy failure?
Cobellis, Luigi; Castaldi, Maria Antonietta; Giordano, Valentino; De Franciscis, Pasquale; Signoriello, Giuseppe; Colacurci, Nicola
2014-10-01
The purpose of this study was to develop a clinical tool, the HFI (Hysteroscopy Failure Index), which gives criteria to predict hysteroscopic examination failure. This was a retrospective diagnostic test study, aimed to validate the HFI, set at the Department of Gynaecology, Obstetric and Reproductive Science of the Second University of Naples, Italy. The HFI was applied to our database of 995 consecutive women, who underwent office based to assess abnormal uterine bleeding (AUB), infertility, cervical polyps, and abnormal sonographic patterns (postmenopausal endometrial thickness of more than 5mm, endometrial hyperechogenic spots, irregular endometrial line, suspect of uterine septa). Demographic characteristics, previous surgery, recurrent infections, sonographic data, Estro-Progestins, IUD and menopausal status were collected. Receiver operating characteristic (ROC) curve analysis was used to assess the ability of the model to identify patients who were correctly identified (true positives) divided by the total number of failed hysteroscopies (true positives+false negatives). Positive and Negative Likelihood Ratios with 95%CI were calculated. The HFI score is able to predict office hysteroscopy failure in 76% of cases. Moreover, the Positive likelihood ratio was 11.37 (95% CI: 8.49-15.21), and the Negative likelihood ratio was 0.33 (95% CI: 0.27-0.41). Hysteroscopy failure index was able to retrospectively predict office hysteroscopy failure. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.
The use of early summer mosquito surveillance to predict late summer West Nile virus activity
Ginsberg, Howard S.; Rochlin, Ilia; Campbell, Scott R.
2010-01-01
Utility of early-season mosquito surveillance to predict West Nile virus activity in late summer was assessed in Suffolk County, NY. Dry ice-baited CDC miniature light traps paired with gravid traps were set weekly. Maximum-likelihood estimates of WNV positivity, minimum infection rates, and % positive pools were generally well correlated. However, positivity in gravid traps was not correlated with positivity in CDC light traps. The best early-season predictors of WNV activity in late summer (estimated using maximum-likelihood estimates of Culex positivity in August and September) were early date of first positive pool, low numbers of mosquitoes in July, and low numbers of mosquito species in July. These results suggest that early-season entomological samples can be used to predict WNV activity later in the summer, when most human cases are acquired. Additional research is needed to establish which surveillance variables are most predictive and to characterize the reliability of the predictions.
Elizabeth, Nabiwemba L; Christopher, Orach Garimoi; Patrick, Kolsteren
2013-04-12
Achieving Millennium Development Goal 4 is dependent on significantly reducing neonatal mortality. Low birth weight is an underlying factor in most neonatal deaths. In developing countries the missed opportunity for providing life saving care is mainly a result of failure to identify low birth weight newborns. This study aimed at identifying a reliable anthropometric measurement for screening low birth weight and determining an operational cut-off point in the Uganda setting. This simple measurement is required because of lack of weighing scales in the community, and sometimes in the health facilities. This was a hospital-based cross-sectional study. Two midwives weighed 706 newborns and measured their foot length, head, chest, thigh and mid-upper arm circumferences within 24 hours after birth.Data was analysed using STATA version 10.0. Correlation with birth weight using Pearson's correlation coefficient and Receiver Operating Characteristics curve analysis were done to determine the measure that best predicts birth weight. Sensitivity and specificity were calculated for a range of measures to obtain operational cut-off points; and Likelihood Ratios and Diagnostic Odds Ratio were determined for each cut-off point. Birth weights ranged from 1370-5350 grams with a mean of 3050 grams (SD 0.53) and 85 (12%) babies weighed less than 2500 grams. All anthropometric measurements had a positive correlation with birth weight, with foot length showing the strongest (r = 0.76) and thigh circumference the weakest (r = 0.62) correlations. Foot length had the highest predictive value for low birth weight (AUC = 0.97) followed by mid-upper arm circumference (AUC = 0.94). Foot length and chest circumference had the highest sensitivity (94%) and specificity (90%) respectively for screening low birth weight babies at the selected cut-off points. Chest circumference had a significantly higher positive likelihood ratio (8.7) than any other measure, and foot length had the lowest negative likelihood ratio. Chest circumference and foot length had diagnostic odds ratios of 97% and 77% respectively. Foot length was easier to measure and it involved minimal exposure of the baby to cold. A cut-off of foot length 7.9 cm had sensitivity of 94% and specificity of 83% for predicting low birth weight. This study suggests foot length as the most appropriate predictor for low birth weight in comparison to chest, head, mid-upper arm and thigh circumference in the Uganda setting. Use of low cost and easy to use tools to identify low birth weight babies by village health teams could support community efforts to save newborns.
Jones, Rhiannon; Bhattacharya, Joydeep
2014-01-01
Likelihood thought-action fusion (TAF-L) refers to a cognitive bias in which individuals believe that the mere thought of a negative event increases its likelihood of occurring in reality. TAF-L is most commonly associated with obsessive-compulsive disorder (OCD) but is also present in depression, generalized anxiety disorder and psychosis. We induced TAF-L in individuals with high (High-OC, N = 23) and low (Low-OC, N = 24) levels of OC traits, and used low resolution electromagnetic tomography (LORETA) to localise the accompanying electrical brain activity patterns. The results showed greater TAF-L in the High-OC than in the Low-OC group (p < .005), which was accompanied by significantly greater upper beta frequency (19-30 Hz) activity in the precuneus (p < .05). Further, the precuneus activity was positively correlated with self-reported magnitude of TAF-L (p < .01), suggesting a specific role of this region in this cognitive bias. Results are discussed with reference to self-referential processing and the default-mode network.
Calvert, Eric; Chambers, Gordon Keith; Regan, William; Hawkins, Robert H; Leith, Jordan M
2009-05-01
The diagnosis of a superior labrum anterior posterior (SLAP) lesion through physical examination has been widely reported in the literature. Most of these studies report high sensitivities and specificities, and claim to be accurate, valid, and reliable. The purpose of this study was to critically evaluate these studies to determine if there was sufficient evidence to support the use of the SLAP physical examination tests as valid and reliable diagnostic test procedures. Strict epidemiologic methodology was used to obtain and collate all relevant articles. Sackett's guidelines were applied to all articles. Confidence intervals and likelihood ratios were determined. Fifteen of 29 relevant studies met the criteria for inclusion. Only one article met all of Sackett's critical appraisal criteria. Confidence intervals for both the positive and negative likelihood ratios contained the value 1. The current literature being used as a resource for teaching in medical schools and continuing education lacks the validity necessary to be useful. There are no good physical examination tests that exist for effectively diagnosing a SLAP lesion.
Jones, Rhiannon; Bhattacharya, Joydeep
2013-01-01
Likelihood thought–action fusion (TAF-L) refers to a cognitive bias in which individuals believe that the mere thought of a negative event increases its likelihood of occurring in reality. TAF-L is most commonly associated with obsessive–compulsive disorder (OCD) but is also present in depression, generalized anxiety disorder and psychosis. We induced TAF-L in individuals with high (High-OC, N = 23) and low (Low-OC, N = 24) levels of OC traits, and used low resolution electromagnetic tomography (LORETA) to localise the accompanying electrical brain activity patterns. The results showed greater TAF-L in the High-OC than in the Low-OC group (p < .005), which was accompanied by significantly greater upper beta frequency (19–30 Hz) activity in the precuneus (p < .05). Further, the precuneus activity was positively correlated with self-reported magnitude of TAF-L (p < .01), suggesting a specific role of this region in this cognitive bias. Results are discussed with reference to self-referential processing and the default-mode network. PMID:24371793
Thakur, Jyoti; Pahuja, Sharvan Kumar; Pahuja, Roop
2017-01-01
In 2005, an international pediatric sepsis consensus conference defined systemic inflammatory response syndrome (SIRS) for children <18 years of age, but excluded premature infants. In 2012, Hofer et al. investigated the predictive power of SIRS for term neonates. In this paper, we examined the accuracy of SIRS in predicting sepsis in neonates, irrespective of their gestational age (i.e., pre-term, term, and post-term). We also created two prediction models, named Model A and Model B, using binary logistic regression. Both models performed better than SIRS. We also developed an android application so that physicians can easily use Model A and Model B in real-world scenarios. The sensitivity, specificity, positive likelihood ratio (PLR) and negative likelihood ratio (NLR) in cases of SIRS were 16.15%, 95.53%, 3.61, and 0.88, respectively, whereas they were 29.17%, 97.82%, 13.36, and 0.72, respectively, in the case of Model A, and 31.25%, 97.30%, 11.56, and 0.71, respectively, in the case of Model B. All models were significant with p < 0.001. PMID:29257099
2013-01-01
Background Rapid diagnostic test (RDT) is becoming an alternative way of establishing quickly the diagnosis of malaria infections, by detecting specific malaria antigens in suspected patients’ blood between the China-Myanmar endemic borders areas, towards achieving the National Malaria Elimination programme by 2020. The objective of this study is to evaluate the performance of CareStart™ Malaria Pf/Pan RDT kit for the diagnosis of malaria infections in suspected patients. Blood examination by microscopy was taken as gold standard to evaluate CareStart™ kit’s sensitivity, specificity and predictive value and corrected with PCR assay. Results Overall 126 of 241 (52.28%) malaria cases were detected by microscopy compared to 115 of 241(47.72%) CareStart™ kit and 128 of 241 (53.11%) PCR corrected assay. CareStart™ kit’s sensitivity and specificity for the diagnosis of malaria were 89.68% and 98.26% respectively, compared to standard microscopy, whereas the sensitivity and specificity for falciparum malaria were 88.52% and 98.26%, and for vivax malaria: 90.77% and 100%. The CareStart™ positive predictive values were 98.26% (93.88-99.52%, 95% CI) compared to 100% (96.77-100%, 95% CI) for PCR-corrected, and the negative predictive values of 89.68% (83.15-93.87%, 95% CI) were the same in microscopy as PCR-corrected. The diagnostic accuracy of CareStart™ kit versus microscopy and PCR were 93.78% (89.99-96.19%, 95% CI) and 94.61% (90.99-96.82%, 95% CI) respectively. The likelihood of diagnostic of malaria positive was almost similar between microscopy and CareStart™ kit, with an entropy reduction of 60.0% compared to a weak likelihood of misdiagnosis of 0.10 (0.09-0.12, 95% CI), with an entropy reduction of 36.01%. Conclusion The accuracy of CareStart™ kit is comparable to gold standard microscopy in these areas, it is easy to perform and suitable for cross-border diagnosis and monitoring of local or imported malaria patterns by any local health staff in endemic remotes. PMID:23294729
Xiaodong, Sun; Tambo, Ernest; Chun, Wei; Zhibin, Cheng; Yan, Deng; Jian, Wang; Jiazhi, Wang; Xiaonong, Zhou
2013-01-07
Rapid diagnostic test (RDT) is becoming an alternative way of establishing quickly the diagnosis of malaria infections, by detecting specific malaria antigens in suspected patients' blood between the China-Myanmar endemic borders areas, towards achieving the National Malaria Elimination programme by 2020. The objective of this study is to evaluate the performance of CareStart™ Malaria Pf/Pan RDT kit for the diagnosis of malaria infections in suspected patients. Blood examination by microscopy was taken as gold standard to evaluate CareStart™ kit's sensitivity, specificity and predictive value and corrected with PCR assay. Overall 126 of 241 (52.28%) malaria cases were detected by microscopy compared to 115 of 241(47.72%) CareStart™ kit and 128 of 241 (53.11%) PCR corrected assay. CareStart™ kit's sensitivity and specificity for the diagnosis of malaria were 89.68% and 98.26% respectively, compared to standard microscopy, whereas the sensitivity and specificity for falciparum malaria were 88.52% and 98.26%, and for vivax malaria: 90.77% and 100%. The CareStart™ positive predictive values were 98.26% (93.88-99.52%, 95% CI) compared to 100% (96.77-100%, 95% CI) for PCR-corrected, and the negative predictive values of 89.68% (83.15-93.87%, 95% CI) were the same in microscopy as PCR-corrected. The diagnostic accuracy of CareStart™ kit versus microscopy and PCR were 93.78% (89.99-96.19%, 95% CI) and 94.61% (90.99-96.82%, 95% CI) respectively. The likelihood of diagnostic of malaria positive was almost similar between microscopy and CareStart™ kit, with an entropy reduction of 60.0% compared to a weak likelihood of misdiagnosis of 0.10 (0.09-0.12, 95% CI), with an entropy reduction of 36.01%. The accuracy of CareStart™ kit is comparable to gold standard microscopy in these areas, it is easy to perform and suitable for cross-border diagnosis and monitoring of local or imported malaria patterns by any local health staff in endemic remotes.
Duenngai, Kunyarat; Wangboon, Chompunoot; Sithithaworn, Jiraporn; Watwiengkam, Nattaya; Namwat, Nisana; Techasen, Anchalee; Loilome, Watcharin; Yongvanit, Puangrat; Loukas, Alex; Sithithaworn, Paiboon; Bethony, Jeffrey M.
2015-01-01
Background Many strategies to control opisthorchiasis have been employed in Thailand, but not in the other neighbouring countries. Specific control methods include mass drug administration (MDA) and health education to reduce raw fish consumption. These control efforts have greatly shifted the epidemiology of Opisthorchis viverrini (OV) infection over the last decade from presenting as densely concentrated "heavy" infections in single villages to widespread "light" OV infections distributed over wide geographical areas. Currently, the "gold standard" detection method for OV infection is formalin ethyl-acetate concentration technique (FECT), which has limited diagnostic sensitivity and diagnostic specificity for light OV infections, with OV eggs often confused with eggs of minute intestinal flukes (MIFs) in feces. In this study, we developed and evaluated the diagnostic performance of a monoclonal antibody-based enzyme-linked immunosorbent assay for the measurement of OV excretory-secretory (ES) antigens in urine (urine OV-ES assay) for the diagnosis of opisthorchiasis compared to the gold standard detection FECT method. Methodology We tested several methods for pre-treating urine samples prior to testing the diagnostic performance of the urine OV-ES assay. Using trichloroacetic acid (TCA) pre-treated urine, we compared detection and quantification of OV infection using the urine OV-ES assay versus FECT in OV-endemic areas in Northeastern Thailand. Receiver operating characteristic (ROC) curves were used to determine the diagnostic sensitivity and specificity of the urine OV-ES assay using TCA pre-treated urine, and to establish diagnostic positivity thresholds. The Positive Predictive Value as well as the likelihood of obtaining a positive test result (LR+) or a negative test result (LR-) were calculated for the established diagnostic positivity threshold. Diagnostic risks (Odds Ratios) were estimated using logistic regression. Results When urine samples were pre-treated with TCA prior to use in the urine OV-ES assay, the analytical sensitivity was significantly improved. Using TCA pre-treatment of urine, the urine OV-ES assay had a limit of detection (LoD) of 39 ng/ml compared to the LoD of 52 ng/mL reported for coprological antigen detection methods. Similarly, the urine OV-ES assay correlated significantly with intensity of OV infection as measured by FECT. The urine OV-ES assay was also able to detect 28 individuals as positive from the 63 (44.4%) individuals previously determined to be negative using FECT. The likelihood of a positive diagnosis of OV infection by urine OV-ES assay increased significantly with the intensity of OV infection as determined by FECT. With reference to FECT, the sensitivity and specificity of the urine OV-ES assay was 81% and 70%, respectively. Conclusion The detection of OV-infection by the urine OV-ES assay showed much greater diagnostic sensitivity and diagnostic specificity than the current "gold standard" FECT method for the detection and quantification of OV infection. Due to its ease-of-use, and noninvasive sample collection (urine), the urine OV-ES assay offers the potential to revolutionize the diagnosis of liver fluke infection and provide an effective tool for control and elimination of these tumorigenic parasites. PMID:26485024
Ziapour, Behrad; Haji, Houman Seyedjavady
2015-01-01
Occult pneumothorax represents a diagnostic pitfall during the primary survey of trauma patients, particularly if these patients require early positive pressure ventilation. This study investigated the accuracy of our proposed rapid model of ultrasound transducer positioning during the primary survey of trauma patients after their arrival at the hospital. This diagnostic trial was conducted over 12 months and was based on the results of 84 ultrasound (US) exams performed on patients with severe multiple trauma. Our index test (US) was used to detect pneumothorax in four pre-defined locations on the anterior of each hemi-thorax using the "Anterior Convergent" approach, and its performance was limited to the primary survey. Consecutively, patients underwent chest-computed tomography (CT) with or without chest radiography. The diagnostic findings of both chest radiography and chest ultrasounds were compared to the gold-standard test (CT). The diagnostic sensitivity was 78 % for US and 36.4 % for chest radiography (p < 0.001); the specificity was 92 % for US and 98 % for chest radiography (not significant); the positive predictive values were 74 % for US and 80 % for chest radiography (not significant); the negative predictive values were 94 % for US and 87 % for chest radiography (not significant); the positive likelihood ratio was 10 for US and 18 for chest radiography (p = 0.007); and the negative likelihood ratio was 0.25 for US and 0.65 for chest radiography (p = 0.001). The mean required time for performing the new method was 64 ± 10 s. An absence of the expected diffused dynamic view among ultrasound images obtained from patients with pneumothorax was also observed. We designated this phenomenon "Gestalt Lung Recession." "Anterior convergent" chest US probing represents a brief but efficient model that provides clinicians a safe and accurate exam and adequate resuscitation during critical minutes of the primary survey without interrupting other medical staff activities taking place around the trauma patient. The use of the new concept of "Gestalt Lung Recession" instead of the absence of "lung sliding" might improve the specificity of US in detecting pneumothorax.
Mixture Rasch Models with Joint Maximum Likelihood Estimation
ERIC Educational Resources Information Center
Willse, John T.
2011-01-01
This research provides a demonstration of the utility of mixture Rasch models. Specifically, a model capable of estimating a mixture partial credit model using joint maximum likelihood is presented. Like the partial credit model, the mixture partial credit model has the beneficial feature of being appropriate for analysis of assessment data…
The Effects of Model Misspecification and Sample Size on LISREL Maximum Likelihood Estimates.
ERIC Educational Resources Information Center
Baldwin, Beatrice
The robustness of LISREL computer program maximum likelihood estimates under specific conditions of model misspecification and sample size was examined. The population model used in this study contains one exogenous variable; three endogenous variables; and eight indicator variables, two for each latent variable. Conditions of model…
A Composite Likelihood Inference in Latent Variable Models for Ordinal Longitudinal Responses
ERIC Educational Resources Information Center
Vasdekis, Vassilis G. S.; Cagnone, Silvia; Moustaki, Irini
2012-01-01
The paper proposes a composite likelihood estimation approach that uses bivariate instead of multivariate marginal probabilities for ordinal longitudinal responses using a latent variable model. The model considers time-dependent latent variables and item-specific random effects to be accountable for the interdependencies of the multivariate…
Jeon, Jihyoun; Hsu, Li; Gorfine, Malka
2012-07-01
Frailty models are useful for measuring unobserved heterogeneity in risk of failures across clusters, providing cluster-specific risk prediction. In a frailty model, the latent frailties shared by members within a cluster are assumed to act multiplicatively on the hazard function. In order to obtain parameter and frailty variate estimates, we consider the hierarchical likelihood (H-likelihood) approach (Ha, Lee and Song, 2001. Hierarchical-likelihood approach for frailty models. Biometrika 88, 233-243) in which the latent frailties are treated as "parameters" and estimated jointly with other parameters of interest. We find that the H-likelihood estimators perform well when the censoring rate is low, however, they are substantially biased when the censoring rate is moderate to high. In this paper, we propose a simple and easy-to-implement bias correction method for the H-likelihood estimators under a shared frailty model. We also extend the method to a multivariate frailty model, which incorporates complex dependence structure within clusters. We conduct an extensive simulation study and show that the proposed approach performs very well for censoring rates as high as 80%. We also illustrate the method with a breast cancer data set. Since the H-likelihood is the same as the penalized likelihood function, the proposed bias correction method is also applicable to the penalized likelihood estimators.
Xiong, Yi-Quan; Ma, Shu-Juan; Zhou, Jun-Hua; Zhong, Xue-Shan; Chen, Qing
2016-06-01
Barrett's esophagus (BE) is considered the most important risk factor for development of esophageal adenocarcinoma. Confocal laser endomicroscopy (CLE) is a recently developed technique used to diagnose neoplasia in BE. This meta-analysis was performed to assess the accuracy of CLE for diagnosis of neoplasia in BE. We searched EMBASE, PubMed, Cochrane Library, and Web of Science to identify relevant studies for all articles published up to June 27, 2015 in English. The quality of included studies was assessed using QUADAS-2. Per-patient and per-lesion pooled sensitivity, specificity, positive likelihood ratio, and negative likelihood ratio with 95% confidence intervals (CIs) were calculated. In total, 14 studies were included in the final analysis, covering 789 patients with 4047 lesions. Seven studies were included in the per-patient analysis. Pooled sensitivity and specificity were 89% (95% CI: 0.82-0.94) and 83% (95% CI: 0.78-0.86), respectively. Ten studies were included in the per-lesion analysis. Compared with the PP analysis, the corresponding pooled sensitivity declined to 77% (95% CI: 0.73-0.81) and specificity increased to 89% (95% CI: 0.87-0.90). Subgroup analysis showed that probe-based CLE (pCLE) was superior to endoscope-based CLE (eCLE) in pooled specificity [91.4% (95% CI: 89.7-92.9) vs 86.1% (95% CI: 84.3-87.8)] and AUC for the sROC (0.885 vs 0.762). Confocal laser endomicroscopy is a valid method to accurately differentiate neoplasms from non-neoplasms in BE. It can be applied to BE surveillance and early diagnosis of esophageal adenocarcinoma. © 2015 Journal of Gastroenterology and Hepatology Foundation and John Wiley & Sons Australia, Ltd.
Riewe, E; Neubauer, E; Pfeifer, A C; Schiltenwolf, M
2016-01-01
10% of all individuals in Germany develop persistent symptoms due to nonspecific back pain (NSBP) causing up to 90% of direct and indirect expenses for health care systems. Evidence indicates a strong relationship between chronic nonspecific back pain and psychosocial risk factors. The Örebro Musculoskeletal Pain Screening Questionnaire (ÖMPSQ) and the German Heidelberger Kurzfragebogen Rückenschmerz (HKF-R 10) are deemed valid in prediction of persistent pain, functional loss or amount of sick leave. This study provides and discusses validity criteria for these questionnaires using ROC-curve analyses. Quality measurements included sensitivity and specificity, likelihood-ratio related test-efficiencies and clinical utility in regard to predictive values. 265 patients recruited from primary and secondary care units completed both questionnaires during the same timeframe. From the total, 133 patients returned a 6-month follow-up questionnaire to assess the validity criteria for outcomes of pain, function and sick leave. Based on heterogeneous cut-offs for the ÖMPSQ, sensitivity and specificity were moderate for outcome of pain (72%/75%). Very high sensitivity was observed for function (97%/57%) and high specificity for sick leave (63%/85%). The latter also applied to the HKF-R 10 (pain 50%/84%). Proportions between sensitivity and specificity were unbalanced except for the ÖMPSQ outcome of pain. Likelihood-ratios and positive predictive values ranged from low to moderate. Although the ÖMPSQ may be considered useful in identification of long-term functional loss or pain, over- and underestimation of patients at risk of chronic noncspecific back pain led to limited test-efficiencies and clinical utility for both questionnaires. Further studies are required to quantify the predictive validity of both questionnaires in Germany.
Kim, Daniel J; Francispragasam, Mario; Docherty, Gavin; Silver, Byron; Prager, Ross; Lee, Donna; Maberley, David
2018-05-18
Previous studies of point of care ultrasound (POCUS) have reported high sensitivities and specificities for retinal detachment (RD). Our primary objective was to assess the test characteristics of POCUS performed by a large heterogeneous group of emergency physicians (EPs) for the diagnosis of RD. This was a prospective diagnostic test assessment of POCUS performed by EPs with varying ultrasound experience on a convenience sample of emergency department (ED) patients presenting with flashes or floaters in one or both eyes. After standard ED assessment, EPs performed an ocular POCUS scan targeted to detect the presence or absence of RD. After completing their ED visit, all patients were assessed by a retina specialist who was blinded to the results of the POCUS scan. We calculated sensitivity and specificity with associated exact binomial confidence intervals (CI) using the retina specialist's final diagnosis as the reference standard. A total of 30 EPs enrolled 115 patients, with median age of 60 years and 64% female. The retina specialist diagnosed RD in 16 (14%) cases. The sensitivity and specificity of POCUS for detecting RD was 75% (95% CI 48%-93%) and 94% (95% CI 87%-98%), respectively. The positive likelihood ratio was 12.4 (95% CI 5.4-28.3), and negative likelihood ratio was 0.27 (95% CI 0.11-0.62). A large heterogeneous group of EPs can perform POCUS with high specificity but only intermediate sensitivity for RD. A negative POCUS scan in the ED performed by a heterogeneous group of providers after a one-hour POCUS didactic is not sufficiently sensitive to rule out RD in a patient with new onset flashes or floaters. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.
Man, Wanrong; Hu, Jianqiang; Zhao, Zhijing; Zhang, Mingming; Wang, Tingting; Lin, Jie; Duan, Yu; Wang, Ling; Wang, Haichang; Sun, Dongdong; Li, Yan
2016-09-01
The instantaneous wave-free ratio (iFR) is a new vasodilator-free index of coronary stenosis severity. The aim of this meta-analysis is to assess the diagnostic performance of iFR for the evaluation of coronary stenosis severity with fractional flow reserve as standard reference. We searched PubMed, EMBASE, CENTRAL, ProQuest, Web of Science, and International Clinical Trials Registry Platform (ICTRP) for publications concerning the diagnostic value of iFR. We used a random-effects covariate to synthesize the available data of sensitivity, specificity, positive likelihood ratio (LR+), negative likelihood ratio (LR-), and diagnostic odds ratio (DOR). Overall test performance was summarized by the summary receiver operating characteristic curve (sROC) and the area under the curve (AUC). Eight studies with 1611 subjects were included in the meta-analysis. The pooled sensitivity, specificity, LR+, LR-, and DOR for iFR were respectively 73.3% (70.1-76.2%), 86.4% (84.3-88.3%), 5.71 (4.43-7.37), 0.29 (0.22-0.38), and 20.54 (16.11-26.20). The area under the summary receiver operating characteristic curves for iFR was 0.8786. No publication bias was identified. The available evidence suggests that iFR may be a new, simple, and promising technology for coronary stenosis physiological assessment.
Li, Li; Chen, Shi; Wang, Ke; Huang, Jiao; Liu, Li; Wei, Sheng; Gao, Hong-Yu
2015-01-01
Nodal invasion by colorectal cancer is a critical determinant in estimating patient survival and in choosing appropriate preoperative treatment. The present meta-analysis was designed to evaluate the diagnostic value of endorectal ultrasound (EUS) in preoperative assessment of lymph node involvement in colorectal cancer. We systematically searched PubMed, Web of Science, Embase, and China National Knowledge Infrastructure (CNKI) databases for relevant studies published on or before December 10th, 2014. The sensitivity, specificity, likelihood ratios, diagnostic odds ratio (DOR) and area under the summary receiver operating characteristics curve (AUC) were assessed to estimate the diagnostic value of EUS. Subgroup analysis and meta-regression were performed to explore heterogeneity across studies. Thirty-three studies covering 3,016 subjects were included. The pooled sensitivity and specificity were 0.69 (95%CI: 0.63-0.75) and 0.77 (95%CI: 0.73-0.82), respectively. The positive and negative likelihood ratios were 3.09 (95%CI: 2.52-3.78) and 0.39 (95%CI: 0.32-0.48), respectively. The DOR was 7.84 (95%CI: 5.56-11.08), and AUC was 0.80 (95%CI: 0.77-0.84). This meta-analysis indicated that EUS has moderate diagnostic value in preoperative assessment of lymph node involvement in colorectal cancer. Further refinements in technology and diagnostic criteria are necessary to improve the diagnostic accuracy of EUS.
Zhou, Q; Ye, Z J; Su, Y; Zhang, J C; Shi, H Z
2010-08-01
N-terminal pro-brain natriuretic peptide (NT-proBNP) is a biomarker useful in diagnosis of pleural effusion due to heart failure. Thus far, its overall diagnostic accuracy has not been systematically reviewed. The aim of the present meta-analysis was to establish the overall diagnostic accuracy of the measurement of pleural NT-proBNP for identifying pleural effusion due to heart failure. After a systematic review of English-language studies, sensitivity, specificity, and other measures of accuracy of NT-proBNP concentrations in pleural fluid in the diagnosis of pleural effusion resulting from heart failure were pooled using fixed-effects models. Summary receiver operating characteristic curves were used to summarise overall test performance. Eight publications met the inclusion criteria. The summary estimates for pleural NT-proBNP in the diagnosis of pleural effusion attributable to heart failure were: sensitivity 0.95 (95% CI 0.92 to 0.97), specificity 0.94 (0.92 to 0.96), positive likelihood ratio 14.12 (10.23 to 19.51), negative likelihood ratio 0.06 (0.04 to 0.09) and diagnostic OR 213.87 (122.50 to 373.40). NT-proBNP levels in pleural fluid showed a high diagnostic accuracy and may help accurately differentiate cardiac from non-cardiac conditions in patients presenting with pleural effusion.
Diagnostic performance of skeletal maturity for the assessment of midpalatal suture maturation.
Angelieri, Fernanda; Franchi, Lorenzo; Cevidanes, Lucia H S; McNamara, James A
2015-12-01
The aim of this study was to analyze the diagnostic performance of the cervical vertebral maturation (CVM) method in estimating accurately the stages of maturation of the midpalatal suture. Cone-beam computed tomography (CBCT) images from 142 subjects (84 female, 58 male; mean age, 14.8 ± 9.7 years) were analyzed by 2 calibrated examiners to define, by visual analysis, the maturational stages of the cervical vertebrae and the midpalatal suture. These CBCT images were required by orthodontists and surgeons for diagnosis and treatment purposes. Positive likelihood ratios (LHRs) were calculated to evaluate the diagnostic performance of the CVM stages in identifying the maturational stages of the midpalatal suture. Positive LHRs greater than 10 were found for several cervical vertebral stages (CSs), including CS1 and CS2 for the identification of midpalatal suture stages A and B, CS3 for the diagnosis of midpalatal suture stage C, and CS5 for the assessment of midpalatal suture stages D and E. These positive LHRs indicated large and often conclusive increases in the likelihood that the CVM stages were associated with specific stages of midpalatal suture maturation. At CS4, there were a moderate positive LHR for stage C and low positive LHRs for stages D and E. Most CVM stages can be used for the diagnosis of the stages of maturation of the midpalatal suture, so that CBCT imaging may not be necessary in these patients. In the postpubertal period, however, an assessment of the midpalatal suture maturation using CBCT images may be indicated in deciding between conventional rapid maxillary expansion and surgically assisted rapid maxillary expansion. On the other hand, if the CVM stage cannot be assessed, chronologic age may be a viable alternative to predict some midpalatal suture stages (particularly the early stages). Copyright © 2015 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.
Psychiatric Autoimmunity: N-Methyl-D-Aspartate Receptor IgG and Beyond.
Kruse, Jennifer L; Lapid, Maria I; Lennon, Vanda A; Klein, Christopher J; Toole, Orna O'; Pittock, Sean J; Strand, Edythe A; Frye, Mark A; McKeon, Andrew
2015-01-01
Descriptions of psychiatric autoimmunity beyond N-methyl-D-aspartate (NMDA) receptor encephalitis are sparse. To report the autoimmune psychiatric spectrum currently recognized in Mayo Clinic practice. Medical record review, testing of stored serum and cerebrospinal fluid for IgGs reactive with synaptic receptors and ion channels, neuronal nuclear and cytoplasmic antigens (including glutamic acid decarboxylase 65-kDa isoform) and case-control comparison were conducted. Patients were categorized into group 1, all adult psychiatric inpatients tested for neural autoantibodies (2002-2011; n = 213), and group 2, all Mayo NMDA receptor IgG-positive patients (2009-2013; n = 13); healthy control subjects were also included (n = 173). In group 1, at least 1 serum autoantibody (but not NMDA receptor IgG) was detected in 36 of 213 psychiatric inpatients. In total, 12 patients were determined retrospectively to have high-likelihood autoimmune encephalitic diagnoses. The most commonly detected autoantibody specificities were voltage-gated potassium channel ([Kv1] VGKC) complex (6) and calcium channel (P/Q type or N type; 5). Symptoms seen were as follows: depressive (8), anxious (7), psychotic (7), disorganized (5), suicidal (3), manic (1) and catatonic (1). In group 2, among 13 NMDA receptor IgG-positive patients, 12 had encephalitis; their psychiatric symptoms were as follows: depressive (9), catatonic (9), disorganized (8), anxious (8), psychotic (7), manic (6), and suicidal (3). Catatonic symptoms were more common in the 12 NMDA receptor IgG-positive patients than in the 12 group 1 patients with high likelihood of encephalitis (p = 0.002). Antibody positivities were usually low positive in value among healthy controls (12 of 16 vs 3 of 12 group 1 encephalitis cases, p = 0.025). NMDA receptor IgG was not detected in any healthy control subject. A spectrum of psychiatric autoimmunity beyond NMDA-R IgG may be under-recognized. Diagnosis is facilitated by combining results of comprehensive psychiatric, laboratory, radiologic, and electrophysiologic evaluations. Copyright © 2015 The Academy of Psychosomatic Medicine. Published by Elsevier Inc. All rights reserved.
Herbst, Meghan K.; Rosenberg, Graeme; Daniels, Brock; Gross, Cary P.; Singh, Dinesh; Molinaro, Annette M.; Luty, Seth; Moore, Christopher L.
2016-01-01
Study objective Hydronephrosis is readily visible on ultrasonography and is a strong predictor of ureteral stones, but ultrasonography is a user-dependent technology and the test characteristics of clinician-performed ultrasonography for hydronephrosis are incompletely characterized, as is the effect of ultrasound fellowship training on predictive accuracy. We seek to determine the test characteristics of ultrasonography for detecting hydronephrosis when performed by clinicians with a wide range of experience under conditions of direct patient care. Methods This was a prospective study of patients presenting to an academic medical center emergency department with suspected renal colic. Before computed tomography (CT) results, an emergency clinician performed bedside ultrasonography, recording the presence and degree of hydronephrosis. CT data were abstracted from the dictated radiology report by an investigator blinded to the bedside ultrasonographic results. Test characteristics of bedside ultrasonography for hydronephrosis were calculated with the CT scan as the reference standard, with test characteristics compared by clinician experience stratified into 4 levels: attending physicians with emergency ultrasound fellowship training, attending physicians without emergency ultrasound fellowship training, ultrasound experienced non–attending physician clinicians (at least 2 weeks of ultrasound training), and ultrasound inexperienced non–attending physician clinicians (physician assistants, nurse practitioners, off-service rotators, and first-year emergency medicine residents with fewer than 2 weeks of ultrasound training). Results There were 670 interpretable bedside ultrasonographic tests performed by 144 unique clinicians, 80.9% of which were performed by clinicians directly involved in the care of the patient. On CT, 47.5% of all subjects had hydronephrosis and 47.0% had a ureteral stone. Among all clinicians, ultrasonography had a sensitivity of 72.6% (95% confidence interval [CI] 65.4% to 78.9%), specificity of 73.3% (95% CI 66.1% to 79.4%), positive likelihood ratio of 2.72 (95% CI 2.25 to 3.27), and negative likelihood ratio of 0.37 (95% CI 0.31 to 0.44) for hydronephrosis, using hydronephrosis on CT as the criterion standard. Among attending physicians with fellowship training, ultrasonography had sensitivity of 92.7% (95% CI 83.8% to 96.9%), positive likelihood ratio of 4.97 (95% CI 2.90 to 8.51), and negative likelihood ratio of 0.08 (95% CI 0.03 to 0.23). Conclusion Overall, ultrasonography performed by emergency clinicians was moderately sensitive and specific for detection of hydronephrosis as seen on CT in patients with suspected renal colic. However, presence or absence of hydronephrosis as determined by emergency physicians with fellowship training in ultrasonography yielded more definitive test results. For clinicians without fellowship training, there was no significant difference between groups in the predictive accuracy of the application according to experience level. PMID:24630203
Herbst, Meghan K; Rosenberg, Graeme; Daniels, Brock; Gross, Cary P; Singh, Dinesh; Molinaro, Annette M; Luty, Seth; Moore, Christopher L
2014-09-01
Hydronephrosis is readily visible on ultrasonography and is a strong predictor of ureteral stones, but ultrasonography is a user-dependent technology and the test characteristics of clinician-performed ultrasonography for hydronephrosis are incompletely characterized, as is the effect of ultrasound fellowship training on predictive accuracy. We seek to determine the test characteristics of ultrasonography for detecting hydronephrosis when performed by clinicians with a wide range of experience under conditions of direct patient care. This was a prospective study of patients presenting to an academic medical center emergency department with suspected renal colic. Before computed tomography (CT) results, an emergency clinician performed bedside ultrasonography, recording the presence and degree of hydronephrosis. CT data were abstracted from the dictated radiology report by an investigator blinded to the bedside ultrasonographic results. Test characteristics of bedside ultrasonography for hydronephrosis were calculated with the CT scan as the reference standard, with test characteristics compared by clinician experience stratified into 4 levels: attending physicians with emergency ultrasound fellowship training, attending physicians without emergency ultrasound fellowship training, ultrasound experienced non-attending physician clinicians (at least 2 weeks of ultrasound training), and ultrasound inexperienced non-attending physician clinicians (physician assistants, nurse practitioners, off-service rotators, and first-year emergency medicine residents with fewer than 2 weeks of ultrasound training). There were 670 interpretable bedside ultrasonographic tests performed by 144 unique clinicians, 80.9% of which were performed by clinicians directly involved in the care of the patient. On CT, 47.5% of all subjects had hydronephrosis and 47.0% had a ureteral stone. Among all clinicians, ultrasonography had a sensitivity of 72.6% (95% confidence interval [CI] 65.4% to 78.9%), specificity of 73.3% (95% CI 66.1% to 79.4%), positive likelihood ratio of 2.72 (95% CI 2.25 to 3.27), and negative likelihood ratio of 0.37 (95% CI 0.31 to 0.44) for hydronephrosis, using hydronephrosis on CT as the criterion standard. Among attending physicians with fellowship training, ultrasonography had sensitivity of 92.7% (95% CI 83.8% to 96.9%), positive likelihood ratio of 4.97 (95% CI 2.90 to 8.51), and negative likelihood ratio of 0.08 (95% CI 0.03 to 0.23). Overall, ultrasonography performed by emergency clinicians was moderately sensitive and specific for detection of hydronephrosis as seen on CT in patients with suspected renal colic. However, presence or absence of hydronephrosis as determined by emergency physicians with fellowship training in ultrasonography yielded more definitive test results. For clinicians without fellowship training, there was no significant difference between groups in the predictive accuracy of the application according to experience level. Copyright © 2014 American College of Emergency Physicians. Published by Mosby, Inc. All rights reserved.
Avril, E; Lacroix, S; Vrignaud, B; Moreau-Klein, A; Coste-Burel, M; Launay, E; Gras-Le Guen, C
2016-07-01
We wanted to determine the diagnostic performance of a rapid influenza diagnostic test (RIDT) used bedside in a pediatric emergency department (PED). This was a prospective study over four consecutive winters (2009-2013), comparing the results of a RIDT (QuickVue®) with RT-PCR in children admitted to a PED. Among the 764 children included, we did not observe any significant differences in the diagnostic performance of RIDT except during the H1N1 pandemic. The overall sensitivity of the test was 0.82; the specificity 0.98; the positive and negative likelihood ratios 37.8 and 0.19. The positive and negative post-test probabilities of infection were 98% and 17%. The diagnostic performance was increased for influenza B cases (P = 0.03). RIDTs are suitable for use every winter with few differences in its diagnostic value, except during specific pandemic periods. This test could limit unnecessary complementary exams and guide the prescription of antivirals during influenza epidemic periods in PEDs. Copyright © 2016. Published by Elsevier Inc.
McGuire, Connor; Kristman, Vicki L; Williams-Whitt, Kelly; Reguly, Paula; Shaw, William; Soklaridis, Sophie
2015-01-01
PURPOSE To determine the association between supervisors’ leadership style and autonomy and supervisors’ likelihood of supporting job accommodations for back-injured workers. METHODS A cross-sectional study of supervisors from Canadian and US employers was conducted using a web-based, self-report questionnaire that included a case vignette of a back-injured worker. Autonomy and two dimensions of leadership style (considerate and initiating structure) were included as exposures. The outcome, supervisors’ likeliness to support job accommodation, was measured with the Job Accommodation Scale. We conducted univariate analyses of all variables and bivariate analyses of the JAS score with each exposure and potential confounding factor. We used multivariable generalized linear models to control for confounding factors. RESULTS A total of 796 supervisors participated. Considerate leadership style (β= .012; 95% CI: .009–.016) and autonomy (β= .066; 95% CI: .025–.11) were positively associated with supervisors’ likelihood to accommodate after adjusting for appropriate confounding factors. An initiating structure leadership style was not significantly associated with supervisors’ likelihood to accommodate (β = .0018; 95% CI: −.0026–.0061) after adjusting for appropriate confounders. CONCLUSIONS Autonomy and a considerate leadership style were positively associated with supervisors’ likelihood to accommodate a back-injured worker. Providing supervisors with more autonomy over decisions of accommodation and developing their considerate leadership style may aid in increasing work accommodation for back-injured workers and preventing prolonged work disability. PMID:25595332
Multiple-hit parameter estimation in monolithic detectors.
Hunter, William C J; Barrett, Harrison H; Lewellen, Tom K; Miyaoka, Robert S
2013-02-01
We examine a maximum-a-posteriori method for estimating the primary interaction position of gamma rays with multiple interaction sites (hits) in a monolithic detector. In assessing the performance of a multiple-hit estimator over that of a conventional one-hit estimator, we consider a few different detector and readout configurations of a 50-mm-wide square cerium-doped lutetium oxyorthosilicate block. For this study, we use simulated data from SCOUT, a Monte-Carlo tool for photon tracking and modeling scintillation- camera output. With this tool, we determine estimate bias and variance for a multiple-hit estimator and compare these with similar metrics for a one-hit maximum-likelihood estimator, which assumes full energy deposition in one hit. We also examine the effect of event filtering on these metrics; for this purpose, we use a likelihood threshold to reject signals that are not likely to have been produced under the assumed likelihood model. Depending on detector design, we observe a 1%-12% improvement of intrinsic resolution for a 1-or-2-hit estimator as compared with a 1-hit estimator. We also observe improved differentiation of photopeak events using a 1-or-2-hit estimator as compared with the 1-hit estimator; more than 6% of photopeak events that were rejected by likelihood filtering for the 1-hit estimator were accurately identified as photopeak events and positioned without loss of resolution by a 1-or-2-hit estimator; for PET, this equates to at least a 12% improvement in coincidence-detection efficiency with likelihood filtering applied.
Assistive technology use and human rights enjoyment: a cross-sectional study in Bangladesh.
Borg, Johan; Larsson, Stig; Ostergren, Per-Olof; Rahman, Asm Atiqur; Bari, Nazmul; Khan, Ahm Noman
2012-09-19
About half a billion people with disabilities in developing countries have limited access to assistive technology. The Convention on the Rights of persons with Disabilities requires governments to take measures to ensure provision of such technologies. To guide implementation of these measures there is a need for understanding health outcomes from a human rights perspective. The objective of this study was therefore to explore the relation between assistive technology use and enjoyment of human rights in a low-income country. Data was collected in eight districts of Bangladesh through interviews of people with hearing impairments using and not using hearings aids, and people with ambulatory impairments using and not using manual wheelchairs (N = 583). Using logistic regression, self-reported outcomes on standard of living, health, education, work, receiving information and movement were analyzed. The adjusted likelihood of reporting greater enjoyment of human rights was significantly higher among people using hearing aids compared to non-users for all outcomes except working status. Compared to non-users, users of wheelchairs reported a significantly higher adjusted likelihood of good ambulatory performance and a significantly lower adjusted likelihood of reporting a positive working status. Further analyses indicated that physical accessibility to working places and duration of wheelchair use had a statistically significant impact on the likelihood of reporting positive work outcomes. The findings support the notion that assistive technology use increases the likelihood of human rights enjoyment, particularly hearing aid use. Physical accessibility should always be addressed in wheelchair provision.
Factors associated with high-quality/low-cost hospital performance.
Jiang, H Joanna; Friedman, Bernard; Begun, James W
2006-01-01
This study explores organizational and market characteristics associated with superior hospital performance in both quality and cost of care, using the Healthcare Cost and Utilization Project State Inpatient Databases for ten states in 1997 and 2001. After controlling for a variety of patient factors, we found that for-profit ownership, hospital competition, and the number of HMOs were positively associated with the likelihood of attaining high-quality/low-cost performance. Furthermore, we examined interactions between organizational and market characteristics and identified a number of significant interactions. For example, the positive likelihood associated with for-profit hospitals diminished in markets with high HMO penetration.
Brown, Joshua W.
2009-01-01
The error likelihood computational model of anterior cingulate cortex (ACC) (Brown & Braver, 2005) has successfully predicted error likelihood effects, risk prediction effects, and how individual differences in conflict and error likelihood effects vary with trait differences in risk aversion. The same computational model now makes a further prediction that apparent conflict effects in ACC may result in part from an increasing number of simultaneously active responses, regardless of whether or not the cued responses are mutually incompatible. In Experiment 1, the model prediction was tested with a modification of the Eriksen flanker task, in which some task conditions require two otherwise mutually incompatible responses to be generated simultaneously. In that case, the two response processes are no longer in conflict with each other. The results showed small but significant medial PFC effects in the incongruent vs. congruent contrast, despite the absence of response conflict, consistent with model predictions. This is the multiple response effect. Nonetheless, actual response conflict led to greater ACC activation, suggesting that conflict effects are specific to particular task contexts. In Experiment 2, results from a change signal task suggested that the context dependence of conflict signals does not depend on error likelihood effects. Instead, inputs to ACC may reflect complex and task specific representations of motor acts, such as bimanual responses. Overall, the results suggest the existence of a richer set of motor signals monitored by medial PFC and are consistent with distinct effects of multiple responses, conflict, and error likelihood in medial PFC. PMID:19375509
A Walk on the Wild Side: The Impact of Music on Risk-Taking Likelihood.
Enström, Rickard; Schmaltz, Rodney
2017-01-01
From a marketing perspective, there has been substantial interest in on the role of risk-perception on consumer behavior. Specific 'problem music' like rap and heavy metal has long been associated with delinquent behavior, including violence, drug use, and promiscuous sex. Although individuals' risk preferences have been investigated across a range of decision-making situations, there has been little empirical work demonstrating the direct role music may have on the likelihood of engaging in risky activities. In the exploratory study reported here, we assessed the impact of listening to different styles of music while assessing risk-taking likelihood through a psychometric scale. Risk-taking likelihood was measured across ethical, financial, health and safety, recreational and social domains. Through the means of a canonical correlation analysis, the multivariate relationship between different music styles and individual risk-taking likelihood across the different domains is discussed. Our results indicate that listening to different types of music does influence risk-taking likelihood, though not in areas of health and safety.
A Walk on the Wild Side: The Impact of Music on Risk-Taking Likelihood
Enström, Rickard; Schmaltz, Rodney
2017-01-01
From a marketing perspective, there has been substantial interest in on the role of risk-perception on consumer behavior. Specific ‘problem music’ like rap and heavy metal has long been associated with delinquent behavior, including violence, drug use, and promiscuous sex. Although individuals’ risk preferences have been investigated across a range of decision-making situations, there has been little empirical work demonstrating the direct role music may have on the likelihood of engaging in risky activities. In the exploratory study reported here, we assessed the impact of listening to different styles of music while assessing risk-taking likelihood through a psychometric scale. Risk-taking likelihood was measured across ethical, financial, health and safety, recreational and social domains. Through the means of a canonical correlation analysis, the multivariate relationship between different music styles and individual risk-taking likelihood across the different domains is discussed. Our results indicate that listening to different types of music does influence risk-taking likelihood, though not in areas of health and safety. PMID:28539908
Mwanza, Jean-Claude; Budenz, Donald L; Godfrey, David G; Neelakantan, Arvind; Sayyad, Fouad E; Chang, Robert T; Lee, Richard K
2014-04-01
To evaluate the glaucoma diagnostic performance of ganglion cell inner-plexiform layer (GCIPL) parameters used individually and in combination with retinal nerve fiber layer (RNFL) or optic nerve head (ONH) parameters measured with Cirrus HD-OCT (Carl Zeiss Meditec, Inc, Dublin, CA). Prospective cross-sectional study. Fifty patients with early perimetric glaucoma and 49 age-matched healthy subjects. Three peripapillary RNFL and 3 macular GCIPL scans were obtained in 1 eye of each participant. A patient was considered glaucomatous if at least 2 of the 3 RNFL or GCIPL scans had the average or at least 1 sector measurement flagged at 1% to 5% or less than 1%. The diagnostic performance was determined for each GCIPL, RNFL, and ONH parameter as well as for binary or-logic and and-logic combinations of GCIPL with RNFL or ONH parameters. Sensitivity, specificity, positive likelihood ratio (PLR), and negative likelihood ratio (NLR). Among GCIPL parameters, the minimum had the best diagnostic performance (sensitivity, 82.0%; specificity, 87.8%; PLR, 6.69; and NLR, 0.21). Inferior quadrant was the best RNFL parameter (sensitivity, 74%; specificity, 95.9%; PLR, 18.13; and NLR, 0.27), as was rim area (sensitivity, 68%; specificity, 98%; PLR, 33.3; and NLR, 0.33) among ONH parameters. The or-logic combination of minimum GCIPL and average RNFL provided the overall best diagnostic performance (sensitivity, 94%; specificity, 85.7%; PRL, 6.58; and NLR, 0.07) as compared with the best RNFL, best ONH, and best and-logic combination (minimum GCIPL and inferior quadrant RNFL; sensitivity, 64%; specificity, 100%; PLR, infinity; and NPR, 0.36). The binary or-logic combination of minimum GCIPL and average RNFL or rim area provides better diagnostic performances than those of and-logic combinations or best single GCIPL, RNFL, or ONH parameters. This finding may be clinically valuable for the diagnosis of early glaucoma. Copyright © 2014 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.
Case finding of lifestyle and mental health disorders in primary care: validation of the ‘CHAT’ tool
Goodyear-Smith, Felicity; Coupe, Nicole M; Arroll, Bruce; Elley, C Raina; Sullivan, Sean; McGill, Anne-Thea
2008-01-01
Background Primary care is accessible and ideally placed for case finding of patients with lifestyle and mental health risk factors and subsequent intervention. The short self-administered Case-finding and Help Assessment Tool (CHAT) was developed for lifestyle and mental health assessment of adult patients in primary health care. This tool checks for tobacco use, alcohol and other drug misuse, problem gambling, depression, anxiety and stress, abuse, anger problems, inactivity, and eating disorders. It is well accepted by patients, GPs and nurses. Aim To assess criterion-based validity of CHAT against a composite gold standard. Design of study Conducted according to the Standards for Reporting of Diagnostic Accuracy statement for diagnostic tests. Setting Primary care practices in Auckland, New Zealand. Method One thousand consecutive adult patients completed CHAT and a composite gold standard. Sensitivities, specificities, positive and negative predictive values, and likelihood ratios were calculated. Results Response rates for each item ranged from 79.6 to 99.8%. CHAT was sensitive and specific for almost all issues screened, except exercise and eating disorders. Sensitivity ranged from 96% (95% confidence interval [CI] = 87 to 99%) for major depression to 26% (95% CI = 22 to 30%) for exercise. Specificity ranged from 97% (95% CI = 96 to 98%) for problem gambling and problem drug use to 40% (95% CI = 36 to 45%) for exercise. All had high likelihood ratios (3–30), except exercise and eating disorders. Conclusion CHAT is a valid and acceptable case-finding tool for most common lifestyle and mental health conditions. PMID:18186993
Tong, Xiang; Wang, Ye; Wang, Chengdi; Jin, Jing; Tian, Panwen; Li, Weimin
2018-01-01
Objectives Although different methods have been established to detect epidermal growth factor receptor (EGFR) T790M mutation in circulating tumor DNA (ctDNA), a wide range of diagnostic accuracy values were reported in previous studies. The aim of this meta-analysis was to provide pooled diagnostic accuracy measures for droplet digital PCR (ddPCR) in the diagnosis of EGFR T790M mutation based on ctDNA. Materials and methods A systematic review and meta-analysis were carried out based on resources from Pubmed, Web of Science, Embase and Cochrane Library up to October 11, 2017. Data were extracted to assess the pooled sensitivity, specificity, positive likelihood ratio, negative likelihood ratio (NLR), diagnostic OR (DOR), and areas under the summary receiver-operating characteristic curve (SROC). Results Eleven of 311 studies identified have met the including criteria. The sensitivity and specificity of ddPCR for the detection of T790M mutation in ctDNA ranged from 0.0% to 100.0% and 63.2% to 100.0%, respectively. For the pooled analysis, ddPCR had a performance of 70.1% (95% CI, 62.7%–76.7%) sensitivity, 86.9 % (95% CI, 80.6%–91.7%) specificity, 3.67 (95% CI, 2.33–5.79) PLR, 0.41 (95% CI, 0.32–0.55) NLR, and 10.83 (95% CI, 5.86–20.03) DOR, with the area under the SROC curve being 0.82. Conclusion The ddPCR harbored a good performance for detection of EGFR T790M mutation in ctDNA. PMID:29844700
Mosquera, Victor X; Marini, Milagros; Muñiz, Javier; Asorey-Veiga, Vanesa; Adrio-Nazar, Belen; Boix, Ricardo; Lopez-Perez, José M; Pradas-Montilla, Gonzalo; Cuenca, José J
2012-09-01
To develop a risk score based on physical examination and chest X-ray findings to rapidly identify major trauma patients at risk of acute traumatic aortic injury (ATAI). A multicenter retrospective study was conducted with 640 major trauma patients with associated blunt chest trauma classified into ATAI (aortic injury) and NATAI (no aortic injury) groups. The score data set included 76 consecutive ATAI and 304 NATAI patients from a single center, whereas the validation data set included 52 consecutive ATAI and 208 NATAI patients from three independent institutions. Bivariate analysis identified variables potentially influencing the presentation of aortic injury. Confirmed variables by logistic regression were assigned a score according to their corresponding beta coefficient which was rounded to the closest integer value (1-4). Predictors of aortic injury included widened mediastinum, hypotension less than 90 mmHg, long bone fracture, pulmonary contusion, left scapula fracture, hemothorax, and pelvic fracture. Area under receiver operating characteristic curve was 0.96. In the score data set, sensitivity was 93.42 %, specificity 85.85 %, Youden's index 0.79, positive likelihood ratio 6.60, and negative likelihood ratio 0.08. In the validation data set, sensitivity was 92.31 % and specificity 85.1 %. Given the relative infrequency of traumatic aortic injury, which often leads to missed or delayed diagnosis, application of our score has the potential to draw necessary clinical attention to the possibility of aortic injury, thus providing the chance of a prompt specific diagnostic and therapeutic management.
Understanding the properties of diagnostic tests - Part 2: Likelihood ratios.
Ranganathan, Priya; Aggarwal, Rakesh
2018-01-01
Diagnostic tests are used to identify subjects with and without disease. In a previous article in this series, we examined some attributes of diagnostic tests - sensitivity, specificity, and predictive values. In this second article, we look at likelihood ratios, which are useful for the interpretation of diagnostic test results in everyday clinical practice.
Sahi, Kamaldeep Singh; Lee, Karen S; Moss, Alan; Yee, Eric; Allard, Felicia; Brook, Alexander; Mortele, Koenraad J
2015-11-01
The purpose of this study was to describe the MR enterography (MRE) appearance of inflammation of the ileoanal pouch after ileal pouch-anal anastomosis (IPAA) surgery and to correlate it with pouch endoscopic and histopathologic findings. All MRE studies performed between October 1, 2007, and September 30, 2013, for patients who had previously undergone IPAA (n = 54) were retrieved. After review of medical records, the patients who underwent MRE, pouch endoscopy, and biopsy within 90 days (14 men, 14 women; mean age, 42.2 years; range, 24-67 years) were selected for inclusion in the study. Two blinded MRI radiologists in consensus retrospectively evaluated MRE studies for multiple MRI features. Two MRI scores were then calculated: an active and a composite inflammation score. A gastroenterologist retrospectively reviewed the pouch endoscopic images, and a pathologist reviewed the slides; both of these investigators were blinded. Both MRI scores were correlated with the pouch endoscopic and histopathologic findings. The composite MRI score had strong positive correlation with the endoscopic score (r = 0.61; p = 0.0005) but weak positive correlation with the histopathologic score (r = 0.31; p = 0.10, not statistically significant). The active inflammation MRI score had moderate positive correlation with the endoscopic score (r = 0.57; p = 0.0017) and weak positive correlation with the histopathologic score (r = 0.20; p = 0.31, not statistically significant). An MRI score ≥ 4 indicated the best results, with sensitivity of 86%, specificity of 79%, positive predictive value of 80%, negative predictive value of 85%, and accuracy of 82% for pouch inflammation. A positive likelihood ratio of 4.00 and negative likelihood ratio of 0.18 were obtained. In patients who have undergone IPAA surgery, the MRE findings strongly correlate with the pouch endoscopic findings with high sensitivity and positive predictive value for pouch inflammation. Therefore, MRE is a useful noninvasive test performed without ionizing radiation that can be used to evaluate patients with clinical symptoms and possibly alleviate the need for endoscopy in a select patient population.
Wichers, Marieke; Kasanova, Zuzana; Bakker, Jindra; Thiery, Evert; Derom, Catherine; Jacobs, Nele; van Os, Jim
2015-01-01
Many of the decisions and actions in everyday life result from implicit learning processes. Important to psychopathology are, for example, implicit reward-seeking and punishment-avoidant learning processes. It is known that when specific actions get associated with a rewarding experience, such as positive emotions, that this will increase the likelihood that an organism will engage in similar actions in the future. Similarly, when actions get associated with punishing experiences, such as negative emotions, this may reduce the likelihood that the organism will engage in similar actions in the future. This study examines whether we can observe these implicit processes prospectively in the flow of daily life. If such processes take place then we expect that current behaviour can be predicted by how similar behaviour was experienced (in terms of positive and negative affect) at previous measurement moments. This was examined in a sample of 621 female individuals that had participated in an Experience Sampling data collection. Measures of affect and behaviour were collected at 10 semi-random moments of the day for 5 consecutive days. It was examined whether affective experience that was paired with certain behaviours (physical activity and social context) at previous measurements modified the likelihood to show similar behaviours at next measurement moments. Analyses were performed both at the level of observations (a time scale with units of ± 90 min) and at day level (a time scale with units of 24 h). As expected, we found that affect indeed moderated the extent to which previous behaviour predicted similar behaviour later in time, at both beep- and day-level. This study showed that it is feasible to track reward-seeking and punishment-avoidant behaviour prospectively in humans in the flow of daily life. This opens up a new toolbox to examine processes determining goal-oriented behaviour in relation to psychopathology in humans. PMID:26087323
Wichers, Marieke; Kasanova, Zuzana; Bakker, Jindra; Thiery, Evert; Derom, Catherine; Jacobs, Nele; van Os, Jim
2015-01-01
Many of the decisions and actions in everyday life result from implicit learning processes. Important to psychopathology are, for example, implicit reward-seeking and punishment-avoidant learning processes. It is known that when specific actions get associated with a rewarding experience, such as positive emotions, that this will increase the likelihood that an organism will engage in similar actions in the future. Similarly, when actions get associated with punishing experiences, such as negative emotions, this may reduce the likelihood that the organism will engage in similar actions in the future. This study examines whether we can observe these implicit processes prospectively in the flow of daily life. If such processes take place then we expect that current behaviour can be predicted by how similar behaviour was experienced (in terms of positive and negative affect) at previous measurement moments. This was examined in a sample of 621 female individuals that had participated in an Experience Sampling data collection. Measures of affect and behaviour were collected at 10 semi-random moments of the day for 5 consecutive days. It was examined whether affective experience that was paired with certain behaviours (physical activity and social context) at previous measurements modified the likelihood to show similar behaviours at next measurement moments. Analyses were performed both at the level of observations (a time scale with units of ± 90 min) and at day level (a time scale with units of 24 h). As expected, we found that affect indeed moderated the extent to which previous behaviour predicted similar behaviour later in time, at both beep- and day-level. This study showed that it is feasible to track reward-seeking and punishment-avoidant behaviour prospectively in humans in the flow of daily life. This opens up a new toolbox to examine processes determining goal-oriented behaviour in relation to psychopathology in humans.
Family and sexual orientation: the family-demographic correlates of homosexuality in men and women.
Francis, Andrew M
2008-01-01
Using a nationally representative sample of young adults, I identify the family-demographic correlates of sexual orientation in men and women. Hence, I test the maternal immune hypothesis, which posits that the only biodemographic correlate of male homosexuality is the number of older brothers, and there are no biodemographic correlates of female homosexuality. For men, I find that having one older brother does not raise the likelihood of homosexuality. Although having multiple older brothers has a positive coefficient, it is not significant. Moreover, having any older sisters lowers the likelihood of homosexual or bisexual identity. For women, I find that having an older brother or having any sisters decreases the likelihood of homosexuality. Family structure, ethnicity, and education are also significantly correlated with male and female sexual orientation. Therefore, the maternal immune hypothesis cannot explain the entire pattern of family-demographic correlates. The findings are consistent with either biological or social theories of sexual orientation.
On the occurrence of false positives in tests of migration under an isolation with migration model
Hey, Jody; Chung, Yujin; Sethuraman, Arun
2015-01-01
The population genetic study of divergence is often done using a Bayesian genealogy sampler, like those implemented in IMa2 and related programs, and these analyses frequently include a likelihood-ratio test of the null hypothesis of no migration between populations. Cruickshank and Hahn (2014, Molecular Ecology, 23, 3133–3157) recently reported a high rate of false positive test results with IMa2 for data simulated with small numbers of loci under models with no migration and recent splitting times. We confirm these findings and discover that they are caused by a failure of the assumptions underlying likelihood ratio tests that arises when using marginal likelihoods for a subset of model parameters. We also show that for small data sets, with little divergence between samples from two populations, an excellent fit can often be found by a model with a low migration rate and recent splitting time and a model with a high migration rate and a deep splitting time. PMID:26456794
He, Qiqi; Wang, Hanzhang; Kenyon, Jonathan; Liu, Guiming; Yang, Li; Tian, Junqiang; Yue, Zhongjin; Wang, Zhiping
2015-01-01
To use meta-analysis to determine the accuracy of percutaneous core needle biopsy in the diagnosis of small renal masses (SMRs ≤ 4.0 cm). Studies were identified by searching PubMed, Embase, and the Cochrane Library database up to March 2013. Two of the authors independently assessed the study quality using QUADAS-2 tool and extracted data that met the inclusion criteria. The sensitivity, specificity, likelihood ratios, diagnostic odds ratio (DOR) and also summary receiver operating characteristic (SROC) curve were investigated and draw. Deek's funnel plot was used to evaluate the publication bias. A total of 9 studies with 788 patients (803 biopsies) were included. Failed biopsies without repeated or aborted from follow-up/surgery result were excluded (232 patients and 353 biopsies). For all cases, the pooled sensitivity was 94.0% (95% CI: 91.0%, 95.0%), the pooled positive likelihood was 22.57 (95 % CI: 9.20-55.34), the pooled negative likelihood was 0.09 (95 % CI: 0.06-0.13), the pooled DOR was 296.52(95 % CI: 99. 42-884.38). The area under the curve of SROC analysis was 0.959 ± 0.0254. Imaging-guided percutaneous core needle biopsy of small renal masses (SMRs ≤ 4.0 cm) is highly accurate to malignant tumor diagnosis with unknown metastatic status and could be offered to some patients after clinic judgment prior to surgical intervention consideration.
Segura-Jiménez, Víctor; Carbonell-Baeza, Ana; Keating, Xiaofen D; Ruiz, Jonatan R; Castro-Piñero, José
2015-04-01
Psychological positive health and health complaints have long been ignored scientifically. Sleep plays a critical role in children and adolescents development. We aimed at studying the association of sleep duration and quality with psychological positive health and health complaints in children and adolescents from southern Spain. A randomly selected two-phase sample of 380 healthy Caucasian children (6-11.9 years) and 304 adolescents (12-17.9 years) participated in the study. Sleep duration (total sleep time), perceived sleep quality (morning tiredness and sleep latency), psychological positive health and health complaints were assessed using the Health Behaviour in School-aged Children questionnaire. The mean (standard deviation [SD]) reported sleep time for children and adolescents was 9.6 (0.6) and 8.8 (0.6) h/day, respectively. Sleep time ≥10 h was significantly associated with an increased likelihood of reporting no health complaints (OR 2.3; P = 0.005) in children, whereas sleep time ≥9 h was significantly associated with an increased likelihood of overall psychological positive health and no health complaints indicators (OR ~ 2; all P < 0.05) in adolescents. Reporting better sleep quality was associated with an increased likelihood of reporting excellent psychological positive health (ORs between 1.5 and 2.6; all P < 0.05). Furthermore, children and adolescents with no difficulty falling asleep were more likely to report no health complaints (OR ~ 3.5; all P < 0.001). Insufficient sleep duration and poor perceived quality of sleep might directly impact quality of life in children, decreasing general levels of psychological positive health and increasing the frequency of having health complaints.
What affects public acceptance of recycled and desalinated water?
Dolnicar, Sara; Hurlimann, Anna; Grün, Bettina
2011-01-01
This paper identifies factors that are associated with higher levels of public acceptance for recycled and desalinated water. For the first time, a wide range of hypothesized factors, both of socio-demographic and psychographic nature, are included simultaneously. The key results, based on a survey study of about 3000 respondents are that: (1) drivers of the stated likelihood of using desalinated water differ somewhat from drivers of the stated likelihood of using recycled water; (2) positive perceptions of, and knowledge about, the respective water source are key drivers for the stated likelihood of usage; and (3) awareness of water scarcity, as well as prior experience with using water from alternative sources, increases the stated likelihood of use. Practical recommendations for public policy makers, such as key messages to be communicated to the public, are derived. PMID:20950834
Li, Gen; Li, Feng; Zhao, Hui-Min; Wen, Han-Li; Li, Hai-Cong; Li, Chun-Ling; Ji, Ping; Xu, Peng; Wu, Kang; Hu, Zhi-Dong; Lu, Shui-Hua; Lowrie, Douglas B; Lv, Jian-Xin; Fan, Xiao-Yong
2017-01-01
Blood-based interferon-gamma (IFN-γ) release assays (IGRAs) have been proven to be useful in the diagnosis of Mycobacterium tuberculosis ( Mtb ) infection. However, IGRAs have not been recommended for clinical practice in most low-income settings due to cost-intensive limitations and shortage of clinical data available. The established T-SPOT. TB assay containing Mtb -specific antigens ESAT-6 and CFP10 are widely used for immunodiagonsis of Mtb infection, but the high cost is one of the restricting factors against its clinical application in the developing countries. More recently, a cost-saving IGRA assay, TS-SPOT, was approved in China. This new assay contains an additional antigen Rv3615c. Rv3615c contains broadly recognized CD4 + and CD8 + epitopes, and T-cell responses to Rv3615c are as specific for Mtb infection as the responses to ESAT-6 and CFP10 in both Mtb -infected humans and M. bovis -infected cattle. Therefore, we assessed the likely effect of inclusion of Rv3615c as stimulus besides ESAT-6 and CFP10 in an IGRA assay and evaluated the performance of TS-SPOT for diagnosis of Mtb infection and active TB compared with T-SPOT. TB . We tested 155 active TB patients, 90 non-TB lung disease patients, and 55 healthy individuals. The results presented an improved positive rate for diagnosis of active TB and Mtb infection, that could be attributable to inclusion of Rv3615c in the mixture of stimulatory antigens. The diagnostic efficiency of TS-SPOT assay for active TB was as follows: sensitivity 80.00%, specificity 83.45%, positive predictive value (PPV) 83.78%, negative predictive value (NPV) 83.45%, positive likelihood ratio (LR+) 4.83, and negative likelihood ratio (LR-) 0.24. The results were similar to those of T-SPOT. TB , with an excellent agreement (κ = 0.91, 95% CI: 0.85-0.95) being observed between these two assays. The sensitivities of the TS-SPOT assay varied for patients with different forms of active TB, with the highest sensitivity for patients with culture-positive pulmonary TB (92.16%) and the lowest for those with tuberculosis meningitis (50.00%). Taken together, the current evidence indicates that this new TS-SPOT assay is a useful adjunct to the current tests for rapid diagnosis of active TB and Mtb infection in low-income and high-incidence settings due to its characteristics of cost-effectiveness and high-quality.
Niemi, Laura; Young, Liane
2013-01-01
Prior work has established robust diversity in the extent to which different moral values are endorsed. Some people focus on values related to caring and fairness, whereas others assign additional moral weight to ingroup loyalty, respect for authority and established hierarchies, and purity concerns. Five studies explore associations between endorsement of distinct moral values and a suite of interpersonal orientations: Machiavellianism, prosocial resource distribution, Social Dominance Orientation, and reported likelihood of helping and not helping kin and close friends versus acquaintances and neighbors. We found that Machiavellianism (Studies 1, 3, 4, 5) (e.g., amorality, controlling and status-seeking behaviors) and Social Dominance Orientation (Study 4) were negatively associated with caring values, and positively associated with valuation of authority. Those higher in caring values were more likely to choose prosocial resource distributions (Studies 2, 3, 4) and to report reduced likelihood of failing to help kin/close friends or acquaintances (Study 4). Finally, greater likelihood of helping acquaintances was positively associated with all moral values tested except authority values (Study 4). The current work offers a novel approach to characterizing moral values and reveals a striking divergence between two kinds of moral values in particular: caring values and authority values. Caring values were positively linked with prosociality and negatively associated with Machiavellianism, whereas authority values were positively associated with Machiavellianism and Social Dominance Orientation.
Galvan, Frank H.; Bogart, Laura M.; Wagner, Glenn J.; Klein, David J.; Chen, Ying-Tung
2014-01-01
HIV-positive Latino men have been found to have poorer medication adherence compared to Whites. This study sought to identify how cultural conceptualisations of masculinity are associated with self-reported medication adherence among Latino men. 208 HIV-positive men reported the number of doses of antiretroviral medication missed in the previous seven days (dichotomised at 100% adherence versus less). Conceptualisations of masculinity consisted of traditional machismo (e.g., power and aggressive attitudes, which are normally associated with negative stereotypes of machismo) and caballerismo (e.g., fairness, respect for elders and the importance of family). Multivariate logistic regression was used to identify factors associated with adherence. The mean adherence was 97% (SD 6.5%; range = 57%–100%). 100% adherence in the previous seven days was reported by 77% of the participants. Caballerismo was associated with a greater likelihood (OR: 1.77; 95% CI: 1.08–2.92; p = 0.03) and machismo with a lower likelihood (OR: 0.60; 95% CI: 0.38–0.95; p = 0.03) of medication adherence. In addition, higher medication side effects were found to be associated with a lower likelihood (OR: 0.59; 95% CI: 0.43–0.81; p = 0.001) of medication adherence. These findings reinforce the importance of identifying cultural factors which may affect medication adherence among HIV-positive Latino men resident in the USA. PMID:24730591
Niemi, Laura; Young, Liane
2013-01-01
Prior work has established robust diversity in the extent to which different moral values are endorsed. Some people focus on values related to caring and fairness, whereas others assign additional moral weight to ingroup loyalty, respect for authority and established hierarchies, and purity concerns. Five studies explore associations between endorsement of distinct moral values and a suite of interpersonal orientations: Machiavellianism, prosocial resource distribution, Social Dominance Orientation, and reported likelihood of helping and not helping kin and close friends versus acquaintances and neighbors. We found that Machiavellianism (Studies 1, 3, 4, 5) (e.g., amorality, controlling and status-seeking behaviors) and Social Dominance Orientation (Study 4) were negatively associated with caring values, and positively associated with valuation of authority. Those higher in caring values were more likely to choose prosocial resource distributions (Studies 2, 3, 4) and to report reduced likelihood of failing to help kin/close friends or acquaintances (Study 4). Finally, greater likelihood of helping acquaintances was positively associated with all moral values tested except authority values (Study 4). The current work offers a novel approach to characterizing moral values and reveals a striking divergence between two kinds of moral values in particular: caring values and authority values. Caring values were positively linked with prosociality and negatively associated with Machiavellianism, whereas authority values were positively associated with Machiavellianism and Social Dominance Orientation. PMID:24349095
Grandparental investment and reproductive decisions in the longitudinal 1970 British cohort study.
Waynforth, David
2012-03-22
There has been a recent increase in interest among evolutionary researchers in the hypothesis that humans evolved as cooperative breeders, using extended family support to help decrease offspring mortality and increase the number of children that can be successfully reared. In this study, data drawn from the 1970 longitudinal British cohort study were analysed to determine whether extended family support encourages fertility in contemporary Britain. The results showed that at age 30, reported frequency that participants saw their own parents (but not in-laws) and the closeness of the bond between the participant and their own parents were associated with an increased likelihood of having a child between ages 30 and 34. Financial help and reported grandparental childcare were not significantly positively associated with births from age 30 to 34. Men's income was positively associated with likelihood of birth, whereas women's income increased likelihood of birth only for working women with at least one child. While it was predicted that grandparental financial and childcare help would increase the likelihood of reproduction by lowering the cost to the parent of having a child, it appears that the mere physical presence of supportive parents rather than their financial or childcare help encouraged reproduction in the 1970 British birth cohort sample.
Prosocial Bystander Behavior in Bullying Dynamics: Assessing the Impact of Social Capital.
Evans, Caroline B R; Smokowski, Paul R
2015-12-01
Individuals who observe a bullying event, but are not directly involved as a bully or victim, are referred to as bystanders. Prosocial bystanders are those individuals who actively intervene in bullying dynamics to support the victim and this prosocial behavior often ends the bullying. The current study examines how social capital in the form of social support, community engagement, mental health functioning, and positive school experiences and characteristics is associated with the likelihood of engaging in prosocial bystander behavior in a large sample (N = 5752; 51.03% female) of racially/ethnically diverse rural youth. It was hypothesized that social capital would be associated with an increased likelihood of engaging in prosocial bystander behavior. Following multiple imputation, an ordered logistic regression with robust standard errors was run. The hypothesis was partially supported and results indicated that social capital in the form of friend and teacher support, ethnic identity, religious orientation, and future optimism were significantly associated with an increased likelihood of engaging in prosocial bystander behavior. Contrary to the hypothesis, a decreased rate of self-esteem was significantly associated with an increased likelihood of engaging in prosocial bystander behavior. The findings highlight the importance of positive social relationships and community engagement in increasing prosocial bystander behavior and ultimately decreasing school bullying. Implications were discussed.
Huysal, Kağan; Budak, Yasemin U; Karaca, Ayse Ulusoy; Aydos, Murat; Kahvecioğlu, Serdar; Bulut, Mehtap; Polat, Murat
2013-01-01
Urinary tract infection (UTI) is one of the most common types of infection. Currently, diagnosis is primarily based on microbiologic culture, which is time- and labor-consuming. The aim of this study was to assess the diagnostic accuracy of urinalysis results from UriSed (77 Electronica, Budapest, Hungary), an automated microscopic image-based sediment analyzer, in predicting positive urine cultures. We examined a total of 384 urine specimens from hospitalized patients and outpatients attending our hospital on the same day for urinalysis, dipstick tests and semi-quantitative urine culture. The urinalysis results were compared with those of conventional semiquantitative urine culture. Of 384 urinary specimens, 68 were positive for bacteriuria by culture, and were thus considered true positives. Comparison of these results with those obtained from the UriSed analyzer indicated that the analyzer had a specificity of 91.1%, a sensitivity of 47.0%, a positive predictive value (PPV) of 53.3% (95% confidence interval (CI) = 40.8-65.3), and a negative predictive value (NPV) of 88.8% (95% CI = 85.0-91.8%). The accuracy was 83.3% when the urine leukocyte parameter was used, 76.8% when bacteriuria analysis of urinary sediment was used, and 85.1% when the bacteriuria and leukocyturia parameters were combined. The presence of nitrite was the best indicator of culture positivity (99.3% specificity) but had a negative likelihood ratio of 0.7, indicating that it was not a reliable clinical test. Although the specificity of the UriSed analyzer was within acceptable limits, the sensitivity value was low. Thus, UriSed urinalysis resuIts do not accurately predict the outcome of culture.
A Positive Affective Neuroendocrinology Approach to Reward and Behavioral Dysregulation
Welker, Keith M.; Gruber, June; Mehta, Pranjal H.
2015-01-01
Emerging lines of research suggest that both testosterone and maladaptive reward processing can modulate behavioral dysregulation. Yet, to date, no integrative account has been provided that systematically explains neuroendocrine function, dysregulation of reward, and behavioral dysregulation in a unified perspective. This is particularly important given specific neuroendocrine systems are potential mechanisms underlying and giving rise to reward-relevant behaviors. In this review, we propose a forward-thinking approach to study the mechanisms of reward and behavioral dysregulation from a positive affective neuroendocrinology (PANE) perspective. This approach holds that testosterone increases reward processing and motivation, which increase the likelihood of behavioral dysregulation. Additionally, the PANE framework holds that reward processing mediates the effects of testosterone on behavioral dysregulation. We also explore sources of potential sex differences and the roles of age, cortisol, and individual differences within the PANE framework. Finally, we discuss future prospects for research questions and methodology in the emerging field of affective neuroendocrinology. PMID:26191007
Gil, A.; González, A.; Dal-Ré, R.; Dominguez, V.; Astasio, P.; Aguilar, L.
1997-01-01
Diluted dried blood drops on filter paper were compared with serum samples as a specimen source for qualitative anti-HAV antibody determination by ELISA. A total of 298 serum samples and dried blood drops were collected from a population of healthy adolescents (15.3 +/- 1.2 years old). The prevalence of anti-HAV antibody obtained by testing serum samples was 7.7% (95% CI:4.8 10.1). Compared with serum sampling the sensitivity and specificity of diluted dried blood drops were 91.3 and 99.3%. The positive and negative predictive values were 91.3 and 99.3%, respectively, and the likelihood ratios of positive and negative results were 91 and 0.09. It is proposed that this test represents a reliable procedure for anti-HAV antibody testing. PMID:9129596
Self-Harm and Suicidal Behaviors in Hong Kong Adolescents: Prevalence and Psychosocial Correlates
Shek, Daniel T. L.; Yu, Lu
2012-01-01
The present paper examined the prevalence and psychosocial correlates of adolescent deliberate self-harm (DSH) and suicidal behavior in a representative sample of 3,328 secondary school students in Hong Kong. With reference to the previous year, 32.7% of the students reported at least one form of DSH, 13.7% of the respondents had suicide thoughts, 4.9% devised specific suicidal plans, and 4.7% had actually attempted suicide. Adolescent girls had significantly higher rates of DSH and suicidal behavior than did adolescent boys. Having remarried parents was related to an increased likelihood of DSH and suicide. While high levels of family functioning, overall positive youth development, and academic and school performance predicted low rates of DSH and suicidal behavior, cognitive and behavioral competencies were unexpectedly found to be positively associated with DSH and suicidal behavior. Theoretical and practical implications of the findings are discussed. PMID:22566783
Simons, S O; van der Laan, T; Mulder, A; van Ingen, J; Rigouts, L; Dekhuijzen, P N R; Boeree, M J; van Soolingen, D
2014-10-01
There is an urgent need for rapid and accurate diagnosis of pyrazinamide-resistant multidrug-resistant tuberculosis (MDR-TB). No diagnostic algorithm has been validated in this population. We hypothesized that pncA sequencing added to rpoB mutation analysis can accurately identify patients with pyrazinamide-resistant MDR-TB. We identified from the Dutch national database (2007-11) patients with a positive Mycobacterium tuberculosis culture containing a mutation in the rpoB gene. In these cases, we prospectively sequenced the pncA gene. Results from the rpoB and pncA mutation analysis (pncA added to rpoB) were compared with phenotypic susceptibility testing results to rifampicin, isoniazid and pyrazinamide (reference standard) using the Mycobacterial Growth Indicator Tube 960 system. We included 83 clinical M. tuberculosis isolates containing rpoB mutations in the primary analysis. Rifampicin resistance was seen in 72 isolates (87%), isoniazid resistance in 73 isolates (88%) and MDR-TB in 65 isolates (78%). Phenotypic reference testing identified pyrazinamide-resistant MDR-TB in 31 isolates (48%). Sensitivity of pncA sequencing added to rpoB mutation analysis for detecting pyrazinamide-resistant MDR-TB was 96.8%, the specificity was 94.2%, the positive predictive value was 90.9%, the negative predictive value was 98.0%, the positive likelihood was 16.8 and the negative likelihood was 0.03. In conclusion, pyrazinamide-resistant MDR-TB can be accurately detected using pncA sequencing added to rpoB mutation analysis. We propose to include pncA sequencing in every isolate with an rpoB mutation, allowing for stratification of MDR-TB treatment according to pyrazinamide susceptibility. © 2014 The Authors Clinical Microbiology and Infection © 2014 European Society of Clinical Microbiology and Infectious Diseases.
Jeyaratnam, Jerold; Ter Haar, Nienke M; de Sain-van der Velden, Monique G M; Waterham, Hans R; van Gijn, Mariëlle E; Frenkel, Joost
2016-01-01
In patients suffering from mevalonate kinase deficiency (MKD), the reduced enzyme activity leads to an accumulation of mevalonic acid which is excreted in the urine. This study aims to evaluate the diagnostic value of urinary mevalonic acid measurement in patients with a clinical suspicion of mevalonate kinase deficiency. In this single-center, retrospective analysis, all patients in whom both measurement of mevalonic acid and genetic testing had been performed in the preceding 17 years have been included. The presence of two pathogenic MVK mutations or demonstration of decreased enzyme activity was considered to be the gold standard for the diagnosis of MKD. Sixty-one patients were included in this study. Thirteen of them harbored two MVK mutations; twelve of them showed elevated levels of mevalonic acid. Forty-eight patients did not harbor any MVK mutations, yet five of them excreted increased amounts of mevalonic acid. This corresponds to a sensitivity of 92%, a specificity of 90%, a positive predictive value of 71%, and a negative predictive value of 98%. The positive likelihood ratio is 10 and the negative likelihood ratio is 0.09. MKD seems very unlikely in patients with a normal mevalonic acid excretion, but it cannot be excluded completely. Further, a positive urinary mevalonic acid excretion still requires MVK analysis to confirm the diagnosis of MKD. Therefore, detection of urinary mevalonic acid should not be mandatory before genetic testing. However, as long as genetic testing is not widely available and affordable, measurement of urinary mevalonic acid is a fair way to select patients for MVK gene analysis or enzyme assay.
Piroozmand, Ahmad; Soltani, Babak; Razavizadeh, Mohsen; Matini, Amir Hasan; Gilasi, Hamid Reza; Zavareh, Abbas Nassaji; Soltani, Siamak
2017-12-01
Helicobacter pylori ( H. pylori ) is an important and common contagious human pathogen which may cause peptic ulcer and also gastric cancer. The definite diagnosis of it is made through invasive tests. Recently, non-invasive tests including serologic tests of serum and saliva have been conducted for diagnosis of H. pylori infection. In this research, the diagnostic values of serum and salivary serology were compared together to use salivary anti- H. pylori test as an alternative method in the future. During this prospective case-control study on patients who were candidates for endoscopy and gastric biopsy from March 2015 to April 2016 in Shahid Beheshti hospital, Kashan, Iran, serum and salivary samples were obtained for measurement of Immunoglobulin G (IgG) antibody levels against H. pylori by enzyme-linked immunosorbent assay (ELISA). Histopathology was the gold standard test. Statistical analysis was performed by SPSS software version 16. Statistical tests included Kolmogorov-Smirnov, independent-samples t-test, Chi-square, Mann-Whitney U, Kruskal-Wallis, McNemar and correlation. Of 123 patients, sixty-one patients (49.6%) were H. pylori -positive according to histology. The median levels of anti- H. pylori antibodies in serum (p<0.001) and saliva (p<0.001) of H. pylori -positive cases were significantly higher than H. pylori -negative cases. Sensitivity, specificity, positive likelihood ratio, negative likelihood ratio and accuracy of serologic tests in serum were 75%, 79%, 3.5, 0.3, 77% and for saliva were 85%, 82%, 4.7, 0.18, 84% respectively. Diagnostic values of salivary ELISA are comparable to serum ELISA and can be used as an alternative modality for diagnosis of H. pylori infection.
International adoption from Ethiopia: An overview of the health status at arrival in Belgium.
Van Kesteren, Lydia; Wojciechowski, Marek
2017-10-01
Ethiopia is a densely populated country with a fast growing economy. Still socioeconomic and health issues render many children parentless. One thousand and twenty eight Ethiopian children have been adopted in Belgium from September 2005 to September 2015. Little has been published about their health status at arrival. Three hundred and fifteen children adopted from Ethiopia were clinically evaluated at the Institute of Tropical Medicine in Antwerp from 1 January 2008 until 31 December 2014. Epidemiological and medical data were collected and analysed retrospectively. Data about 164 boys and 151 girls with a mean age of three years were analysed. Twenty per cent was adequately vaccinated, for 66.7% of children these data were absent. About 8.6% of the children were wasted/thin, 28.9% stunted. Skin abnormalities were seen in 40.3%, especially Tinea capitis. No children tested positive for HIV, syphilis or hepatitis C. Four children had an acute or chronic hepatitis B (HBV) infection, eight children had a cured HBV infection. Two children tested positive for malaria. Active pulmonary tuberculosis was found in six children. Sixty-two per cent had one or more intestinal parasite. Giardia lamblia (41.9%) and Blastocystis hominis (27.0%) were most frequently isolated. There is a statistically relevant association between the number of intestinal parasites and age at presentation. In this group eosinophilia had a sensitivity of 30.2%, a specificity of 79.1% for intestinal parasites and a positive likelihood ratio of 1.44 with a negative likelihood ratio of 0.88. Apart from the high prevalence of stunting and intestinal parasites important medical problems were infrequent. A systematic clinical examination and screening for infectious diseases remain important to ensure a healthy start of a new life in Belgium.
Cadogan, Angela; McNair, Peter; Laslett, Mark; Hing, Wayne; Taylor, Stephen
2013-01-01
Objectives: Rotator cuff tears are a common and disabling complaint. The early diagnosis of medium and large size rotator cuff tears can enhance the prognosis of the patient. The aim of this study was to identify clinical features with the strongest ability to accurately predict the presence of a medium, large or multitendon (MLM) rotator cuff tear in a primary care cohort. Methods: Participants were consecutively recruited from primary health care practices (n = 203). All participants underwent a standardized history and physical examination, followed by a standardized X-ray series and diagnostic ultrasound scan. Clinical features associated with the presence of a MLM rotator cuff tear were identified (P<0.200), a logistic multiple regression model was derived for identifying a MLM rotator cuff tear and thereafter diagnostic accuracy was calculated. Results: A MLM rotator cuff tear was identified in 24 participants (11.8%). Constant pain and a painful arc in abduction were the strongest predictors of a MLM tear (adjusted odds ratio 3.04 and 13.97 respectively). Combinations of ten history and physical examination variables demonstrated highest levels of sensitivity when five or fewer were positive [100%, 95% confidence interval (CI): 0.86–1.00; negative likelihood ratio: 0.00, 95% CI: 0.00–0.28], and highest specificity when eight or more were positive (0.91, 95% CI: 0.86–0.95; positive likelihood ratio 4.66, 95% CI: 2.34–8.74). Discussion: Combinations of patient history and physical examination findings were able to accurately detect the presence of a MLM rotator cuff tear. These findings may aid the primary care clinician in more efficient and accurate identification of rotator cuff tears that may require further investigation or orthopedic consultation. PMID:24421626
Choi, Sungim; Jung, Kyung Hwa; Son, Hyo-Ju; Lee, Seung Hyun; Hong, Jung Min; Kim, Min Chul; Kim, Min Jae; Chong, Yong Pil; Sung, Heungsup; Lee, Sang-Oh; Choi, Sang-Ho; Kim, Yang Soo; Woo, Jun Hee; Kim, Sung-Han
2018-05-01
Interferon (IFN)-γ-releasing assay for diagnosing tuberculosis (TB) has shown promise; however, there are only a few reports on usefulness of the QuantiFERON-TB Gold In-Tube test (QFT-GIT) for diagnosing TB vertebral osteomyelitis. All patients presenting at a tertiary hospital between January 2010 and July 2016 with suspected TB vertebral osteomyelitis were retrospectively enrolled to evaluate the diagnostic performance of QFT-GIT. We used QFT-GIT to measure the IFN-γ response to ESAT-6, CFP-10 and TB7.7. A total of 141 patients were enrolled; 32 (23%) were categorized as having confirmed TB, (1%) as probable TB, 14 (10%) as possible TB and 93 (66%) as not TB. Of these, 16 patients with probable and possible TB were excluded from the final analysis. Chronic granulomas with/without necrosis, acid-fast bacilli stain, M. tuberculosis polymerase chain reaction and cultures for M. tuberculosis were positive in 14 (44%), 12 (38%), 22 (69%) and 28 (88%) patients, respectively, among the 32 patients with confirmed TB. The overall sensitivity, specificity, positive predictive value, negative predictive value, likelihood ratio for a positive result, and likelihood ratio for a negative result of the QFT-GIT for TB vertebral osteomyelitis were 91% (95% confidence interval [CI], 75-98%), 65% (95% CI, 54-75%), 50% (95% CI, 42-58%), 95% (95% CI, 86-98%), 2.59 (95% CI, 1.89-3.55) and 0.14 (95% CI, 0.05-0.43), respectively. The QFT-GIT appears to be a useful adjunct test for diagnosing TB vertebral osteomyelitis because the negative test results may be useful for excluding a diagnosis of active TB vertebral osteomyelitis.
ERIC Educational Resources Information Center
Eaves, Michael
This paper provides a literature review of the elaboration likelihood model (ELM) as applied in persuasion. Specifically, the paper addresses distraction with regard to effects on persuasion. In addition, the application of proxemic violations as peripheral cues in message processing is discussed. Finally, the paper proposes to shed new light on…
De Yébenes, María Jesús García; Otero, Angel; Zunzunegui, María Victoria; Rodríguez-Laso, Angel; Sánchez-Sánchez, Fernando; Del Ser, Teodoro
2003-10-01
To validate the 'Prueba Cognitiva de Leganés' (PCL) as a screening tool for cognitive impairment in elderly people with little formal education. The PCL is a simple cognitive test with 32 items that includes two scores of orientation and memory and a global score of 0-32 points. It was applied to a population sample of 527 elderly people over 70 with low educational level, who were independently diagnosed by consensus between two neurologists as having normal cognitive function, age associated cognitive decline (AACD, IPA-OMS criteria) or dementia (DSM-IV criteria). Individuals with severe visual or hearing defects and those who rejected the exam were excluded from the study. The PCL was validated in a sample of 375 individuals: 300 normal, 42 with AACD and 33 with dementia. The sensitivity, specificity, accuracy and likelihood ratios, as well as the ROC curves for dementia and for AACD-dementia, were calculated. The confounding effect of sociodemographic variables was assessed by logistic regression analysis and convergent validity by partial correlations of the PCL with other cognitive tests. Inter-rater reliability was evaluated with the intraclass correlation coefficient. The PCL identified dementia (cut-off < or =22) and AACD-dementia (cut-off < or =26), with the following diagnostic parameters, respectively: sensitivity 93.9%-80%, specificity 94.7%-84.3%, positive likelihood ratio 17.8-5.1, negative likelihood ratio 0.06-0.24, and accuracy 94.6%-83.4%. The areas under the ROC curve were 0.985 (95% Confidence Intervals (CI) 0.967-0.995) and 0.904 (95% CI: 0.870-0.932) respectively. The intraclass correlation coefficient was 0.79 (0.74-0.83). The PCL is a simple instrument, which is both valid and reliable, for the screening of dementia in population samples of individuals with low educational level. This instrument could be useful in primary health care. Copyright 2003 John Wiley & Sons, Ltd.
Ernst, Udo A.; Schiffer, Alina; Persike, Malte; Meinhardt, Günter
2016-01-01
Processing natural scenes requires the visual system to integrate local features into global object descriptions. To achieve coherent representations, the human brain uses statistical dependencies to guide weighting of local feature conjunctions. Pairwise interactions among feature detectors in early visual areas may form the early substrate of these local feature bindings. To investigate local interaction structures in visual cortex, we combined psychophysical experiments with computational modeling and natural scene analysis. We first measured contrast thresholds for 2 × 2 grating patch arrangements (plaids), which differed in spatial frequency composition (low, high, or mixed), number of grating patch co-alignments (0, 1, or 2), and inter-patch distances (1° and 2° of visual angle). Contrast thresholds for the different configurations were compared to the prediction of probability summation (PS) among detector families tuned to the four retinal positions. For 1° distance the thresholds for all configurations were larger than predicted by PS, indicating inhibitory interactions. For 2° distance, thresholds were significantly lower compared to PS when the plaids were homogeneous in spatial frequency and orientation, but not when spatial frequencies were mixed or there was at least one misalignment. Next, we constructed a neural population model with horizontal laminar structure, which reproduced the detection thresholds after adaptation of connection weights. Consistent with prior work, contextual interactions were medium-range inhibition and long-range, orientation-specific excitation. However, inclusion of orientation-specific, inhibitory interactions between populations with different spatial frequency preferences were crucial for explaining detection thresholds. Finally, for all plaid configurations we computed their likelihood of occurrence in natural images. The likelihoods turned out to be inversely related to the detection thresholds obtained at larger inter-patch distances. However, likelihoods were almost independent of inter-patch distance, implying that natural image statistics could not explain the crowding-like results at short distances. This failure of natural image statistics to resolve the patch distance modulation of plaid visibility remains a challenge to the approach. PMID:27757076
Matzek, Brett A; Fivecoat, Phillip T; Ritz, Reis B
2014-03-01
Fracture diagnosis in the austere environment where radiographic tests are not available can be a challenge. In the past, a diagnostic technique has been described using a tuning fork and stethoscope to assess decreased sound conduction in the fractured extremity. In this study, we evaluate the use of a cellular phone's vibrate function and a stethoscope to limit equipment carried by expeditionary practitioners. The purpose of this study was to evaluate the accuracy of fracture diagnosis using a cellular phone and stethoscope. This is a pilot study to assess the usefulness of the above technique before clinical implementation. In 3 cadavers, we created fractures of the humerus and femur. Twenty-seven emergency medicine residents and an attending physician performed the diagnostic technique. Overall, the use of the cellular phone and stethoscope resulted in a sensitivity of 73% (95% confidence interval [CI]: 0.64 to 0.81) and a specificity of 83% (95% CI: 0.77 to 0.88), with a positive predicted value of 68% (95% CI: 0.59 to 0.77) and a negative predicted value of 86% (95% CI: 0.81 to 0.90). Positive likelihood ratio was 4.3, and negative likelihood ratio was 0.32. The use of a cellular phone and stethoscope may be a useful tool for the diagnosis of fractures in the austere environment. However, further study is needed to validate these findings in the clinical environment. Published by Wilderness Medical Society on behalf of Wilderness Medical Society.
Tsutsumi, Akizumi; Inoue, Akiomi; Eguchi, Hisashi
2017-07-27
The manual for the Japanese Stress Check Program recommends use of the Brief Job Stress Questionnaire (BJSQ) from among the program's instruments and proposes criteria for defining "high-stress" workers. This study aimed to examine how accurately the BJSQ identifies workers with or without potential psychological distress. We used an online survey to administer the BJSQ with a psychological distress scale (K6) to randomly selected workers (n=1,650). We conducted receiver operating characteristics curve analyses to estimate the screening performance of the cutoff points that the Stress Check Program manual recommends for the BJSQ. Prevalence of workers with potential psychological distress defined as K6 score ≥13 was 13%. Prevalence of "high-risk" workers defined using criteria recommended by the program manual was 16.7% for the original version of the BJSQ. The estimated values were as follows: sensitivity, 60.5%; specificity, 88.9%; Youden index, 0.504; positive predictive value, 47.3%; negative predictive value, 93.8%; positive likelihood ratio, 6.0; and negative likelihood ratio, 0.4. Analyses based on the simplified BJSQ indicated lower sensitivity compared with the original version, although we expected roughly the same screening performance for the best scenario using the original version. Our analyses in which psychological distress measured by K6 was set as the target condition indicate less than half of the identified "high-stress" workers warrant consideration for secondary screening for psychological distress.
Elsafi, Salah H; Alqahtani, Norah I; Zakary, Nawaf Y; Al Zahrani, Eidan M
2015-01-01
To study the performance of a single test using two fecal occult blood tests with colonoscopy for the detection of colorectal cancer (CRC) for the first time in Saudi Arabia to determine possible implications for the anticipated colorectal screening program. We compared the performance of guaiac and immunochemical fecal occult blood tests for the detection of CRC among patients of 50-74 years old attending two hospitals in the Eastern Region of Saudi Arabia. Samples of feces were collected from 257 asymptomatic patients and 20 cases of confirmed CRC, and they were tested simultaneously by the guaiac-based occult blood test and monoclonal antibody-based immunoassay kit. Colonoscopy was performed on all participants and the results were statistically analyzed with both positive and negative occult blood tests of both methods. Of the 277 subjects, 79 tested positive for occult blood with at least one method. Overall, the number of those with an occult blood-positive result by both tests was 39 (14.1%), while for 198 (71.5%), both tests were negative (P<0.0001); 40 (14.4%) samples showed a discrepant result. Colonoscopy data were obtained for all 277 patients. A total of three invasive cancers were detected among the screening group. Of the three, the guaiac test detected two cases, while the immunochemical test detected three of them. Of the 20 control cases, the guaiac test detected 13 CRC cases (P=0.03), while the immunochemical test detected 16 of them (P<0.0001). The sensitivity of guaiac and immunochemical tests for the detection of CRC in the screening group was 50.00% (95% confidence interval [CI] =6.76-93.24) and 75.00% (95% CI =19.41-99.37), respectively. For comparison, the sensitivity of the guaiac fecal occult blood test for detecting CRC among the control group was 65.00% (95% CI =40.78-84.61) while that of FIT was 80.00% (95% CI =56.34-94.27). The specificity of the guaiac and immunoassay tests was 77.87% (95% CI =72.24-82.83) and 90.12% (95% CI =85.76-93.50), respectively. The positive likelihood ratio of guaiac and immunochemical tests for the detection of CRC was 2.26 (95% CI =0.83-6.18) and 7.59 (95% CI =3.86-14.94), whereas the negative likelihood ratio was 0.64 (95% CI =0.24-1.71) and 0.28 (95% CI =0.05-1.52), respectively. The positive predictive values of guaiac and immunochemical tests were 3.45% (95% CI =0.426-11.91) and 10.71% (95% CI =2.27-28.23), respectively. There was no marked difference in the negative predictive values for both methods. The sensitivity of the fecal occult blood test by FIT was significantly higher for stages III and IV colorectal cancer than for stages I and II (P=0.01) and it was insignificant for the guaiac fecal occult blood test (P=0.07). In areas where other advance screening methods of CRC are not feasible, the use of FIT can be considered.
Shriberg, Lawrence D; Strand, Edythe A; Fourakis, Marios; Jakielski, Kathy J; Hall, Sheryl D; Karlsson, Heather B; Mabie, Heather L; McSweeny, Jane L; Tilkens, Christie M; Wilson, David L
2017-04-14
The purpose of this 2nd article in this supplement is to report validity support findings for the Pause Marker (PM), a proposed single-sign diagnostic marker of childhood apraxia of speech (CAS). PM scores and additional perceptual and acoustic measures were obtained from 296 participants in cohorts with idiopathic and neurogenetic CAS, adult-onset apraxia of speech and primary progressive apraxia of speech, and idiopathic speech delay. Adjusted for questionable specificity disagreements with a pediatric Mayo Clinic diagnostic standard, the estimated sensitivity and specificity, respectively, of the PM were 86.8% and 100% for the CAS cohort, yielding positive and negative likelihood ratios of 56.45 (95% confidence interval [CI]: [1.15, 2763.31]) and 0.13 (95% CI [0.06, 0.30]). Specificity of the PM for 4 cohorts totaling 205 participants with speech delay was 98.5%. These findings are interpreted as providing support for the PM as a near-conclusive diagnostic marker of CAS.
The Diagnostic Accuracy of Special Tests for Rotator Cuff Tear: The ROW Cohort Study
Jain, Nitin B.; Luz, Jennifer; Higgins, Laurence D.; Dong, Yan; Warner, Jon J.P.; Matzkin, Elizabeth; Katz, Jeffrey N.
2016-01-01
Objective The aim was to assess diagnostic accuracy of 15 shoulder special tests for rotator cuff tears. Design From 02/2011 to 12/2012, 208 participants with shoulder pain were recruited in a cohort study. Results Among tests for supraspinatus tears, Jobe’s test had a sensitivity of 88% (95% CI=80% to 96%), specificity of 62% (95% CI=53% to 71%), and likelihood ratio of 2.30 (95% CI=1.79 to 2.95). The full can test had a sensitivity of 70% (95% CI=59% to 82%) and a specificity of 81% (95% CI=74% to 88%). Among tests for infraspinatus tears, external rotation lag signs at 0° had a specificity of 98% (95% CI=96% to 100%) and a likelihood ratio of 6.06 (95% CI=1.30 to 28.33), and the Hornblower’s sign had a specificity of 96% (95% CI=93% to 100%) and likelihood ratio of 4.81 (95% CI=1.60 to 14.49). Conclusions Jobe’s test and full can test had high sensitivity and specificity for supraspinatus tears and Hornblower’s sign performed well for infraspinatus tears. In general, special tests described for subscapularis tears have high specificity but low sensitivity. These data can be used in clinical practice to diagnose rotator cuff tears and may reduce the reliance on expensive imaging. PMID:27386812
How to use … the Monospot and other heterophile antibody tests.
Marshall-Andon, Tess; Heinz, Peter
2017-08-01
Epstein-Barr virus (EBV) is a highly prevalent virus, transmitted via saliva, which often causes asymptomatic infection in children but frequently results in infectious mononucleosis in adolescents. Heterophile antibody tests, including the Monospot test, are red cell or latex agglutination assays, which detect antired cell antibodies produced as part of a polyclonal antibody response occurring during EBV infection. Heterophile antibody tests are rapid, cheap and specific tests that can be performed from the onset of symptoms of infectious mononucleosis. In adolescents, heterophile antibody tests have high specificity and sensitivity in the diagnosis of primary acute EBV infection. However, the tests have low sensitivity and low negative predictive value in young children and are not useful under the age of 4. Heterophile tests may be positive in other viral infections, autoimmune disease and haematological malignancies, but do not appear to be positive in primary bacterial infection. Virus-specific serology is required in children under the age of 4 or if an older child is heterophile negative. Virus-specific serology allows diagnosis and the pattern of positivity and negativity enables the clinician to stage the EBV infection. Virus-specific serology appears to have better sensitivity in young children, but there is cross-reaction with other herpesvirus infections, a longer turnaround time and it is more expensive to perform. Further research is needed to establish which children benefit from and hence require testing for heterophile antibodies, the cost-effectiveness of EBV investigations and whether heterophile titres have predictive value for the severity of infection and the likelihood of complications. 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/.
Multiple-Hit Parameter Estimation in Monolithic Detectors
Barrett, Harrison H.; Lewellen, Tom K.; Miyaoka, Robert S.
2014-01-01
We examine a maximum-a-posteriori method for estimating the primary interaction position of gamma rays with multiple interaction sites (hits) in a monolithic detector. In assessing the performance of a multiple-hit estimator over that of a conventional one-hit estimator, we consider a few different detector and readout configurations of a 50-mm-wide square cerium-doped lutetium oxyorthosilicate block. For this study, we use simulated data from SCOUT, a Monte-Carlo tool for photon tracking and modeling scintillation- camera output. With this tool, we determine estimate bias and variance for a multiple-hit estimator and compare these with similar metrics for a one-hit maximum-likelihood estimator, which assumes full energy deposition in one hit. We also examine the effect of event filtering on these metrics; for this purpose, we use a likelihood threshold to reject signals that are not likely to have been produced under the assumed likelihood model. Depending on detector design, we observe a 1%–12% improvement of intrinsic resolution for a 1-or-2-hit estimator as compared with a 1-hit estimator. We also observe improved differentiation of photopeak events using a 1-or-2-hit estimator as compared with the 1-hit estimator; more than 6% of photopeak events that were rejected by likelihood filtering for the 1-hit estimator were accurately identified as photopeak events and positioned without loss of resolution by a 1-or-2-hit estimator; for PET, this equates to at least a 12% improvement in coincidence-detection efficiency with likelihood filtering applied. PMID:23193231
Feehan, Lynne M; Goldsmith, Charles H; Leung, April Y F; Li, Linda C
Purpose: To compare the ability of SenseWear Mini (SWm) and Actigraph GT3X (AG 3 ) accelerometers to differentiate between healthy adults' observed sedentary and light activities in a laboratory setting. Methods: The 22 participants (15 women, 7 men), ages 19 to 72 years, wore SWm and AG 3 monitors and performed five sedentary and four light activities for 5 minutes each while observed in a laboratory setting. Performance was examined through comparisons of accuracy, sensitivity, specificity, positive and negative predictive values, and positive and negative likelihood ratios. Correct identification of both types of activities was examined using area under the receiver operating characteristic curve (AUC). Results: Both monitors demonstrated excellent ability to identify sedentary activities (sensitivity>0.89). The SWm monitor was better at identifying light activities (specificity 0.61-0.71) than the AG 3 monitor (specificity 0.27-0.47) and thus also showed a greater ability to correctly identify both sedentary and light activities (SWm AUC 0.84; AG 3 AUC 0.62-0.73). Conclusions: SWm may be a more suitable monitor for detecting time spent in sedentary and light-intensity activities. This finding has clinical and research relevance for evaluation of time spent in lower intensity physical activities by sedentary adults.
Modeling Goal-Directed User Exploration in Human-Computer Interaction
2011-02-01
scent, other factors including the layout position and grouping of options in the user-interface also affect user exploration and the likelihood of...grouping of options in the user-interface also affect user exploration and the likelihood of success. This dissertation contributes a new model of goal...better inform UI design. 1.1 RESEARCH GAPS IN MODELING In addition to infoscent, the layout of the UI also affects the choices made during
A Maximum Likelihood Approach to Functional Mapping of Longitudinal Binary Traits
Wang, Chenguang; Li, Hongying; Wang, Zhong; Wang, Yaqun; Wang, Ningtao; Wang, Zuoheng; Wu, Rongling
2013-01-01
Despite their importance in biology and biomedicine, genetic mapping of binary traits that change over time has not been well explored. In this article, we develop a statistical model for mapping quantitative trait loci (QTLs) that govern longitudinal responses of binary traits. The model is constructed within the maximum likelihood framework by which the association between binary responses is modeled in terms of conditional log odds-ratios. With this parameterization, the maximum likelihood estimates (MLEs) of marginal mean parameters are robust to the misspecification of time dependence. We implement an iterative procedures to obtain the MLEs of QTL genotype-specific parameters that define longitudinal binary responses. The usefulness of the model was validated by analyzing a real example in rice. Simulation studies were performed to investigate the statistical properties of the model, showing that the model has power to identify and map specific QTLs responsible for the temporal pattern of binary traits. PMID:23183762
The Role of Self-Efficacy for Bystander Helping Behaviors in Risky Alcohol Situations
Krieger, Heather; Serrano, Surizaday; Neighbors, Clayton
2017-01-01
We examined the role of self-efficacy in preventing bystander inaction in dangerous alcohol situations. Participants (N = 504) completed an online survey that assessed whether they had previously witnessed or intervened in alcohol-related emergencies, their self-efficacy for intervening, and their likelihood of intervening in the future. Previously intervening was positively associated with self-efficacy and likelihood of intervening in the future. Furthermore, self-efficacy mediated the association between previously intervening and likelihood of intervening in the future. In conclusion, self-efficacy for intervening in social situations is associated with intervening in alcohol-related emergencies and is an important factor to consider when designing bystander interventions. PMID:29097835
The Role of Self-Efficacy for Bystander Helping Behaviors in Risky Alcohol Situations.
Krieger, Heather; Serrano, Surizaday; Neighbors, Clayton
2017-04-01
We examined the role of self-efficacy in preventing bystander inaction in dangerous alcohol situations. Participants (N = 504) completed an online survey that assessed whether they had previously witnessed or intervened in alcohol-related emergencies, their self-efficacy for intervening, and their likelihood of intervening in the future. Previously intervening was positively associated with self-efficacy and likelihood of intervening in the future. Furthermore, self-efficacy mediated the association between previously intervening and likelihood of intervening in the future. In conclusion, self-efficacy for intervening in social situations is associated with intervening in alcohol-related emergencies and is an important factor to consider when designing bystander interventions.
Caviness, A Chantal; Oelze, Lindsay L; Saz, Ulas E; Greer, Jewel M; Demmler-Harrison, Gail J
2010-09-01
Direct immunofluorescence assay (DFA) is commonly used for the rapid identification of herpes simplex virus (HSV) infection in mucocutaneous lesions, yet little is known about its diagnostic accuracy. To determine the diagnostic yield and accuracy of HSV DFA for the diagnosis of mucocutaneous HSV infection in pediatric patients. Retrospective cross-sectional study of all patients who underwent HSV DFA testing by the Texas Children's Hospital Diagnostic Virology between January 1, 1995 and December 31, 2005. HSV DFA sensitivity, specificity, positive likelihood ratio (LRs), and negative LRs were estimated using viral culture as the reference standard. 659 specimens were submitted for HSV DFA with concurrent viral cultures. Viral cultures were positive for HSV type 1 in 158 (24%) and HSV type 2 in 2 (0.3%). There were 433 different patients with a median age of 8.6 years. Types of lesions were as follows: 50% ulcerative, 26% vesicular, 8% erythema or purpura, 5% pustular, and 11% missing. Of the 659 specimens submitted for HSV DFA, 160 (24%) were inconclusive due to inadequate cells. Of the 499 adequate specimens, overall HSV DFA test accuracy was: sensitivity 61%, specificity 99%, LR positive 40, and LR negative 0.39. A quarter of specimens submitted for HSV DFA testing are not adequate for DFA testing. When HSV DFA can be performed, it is specific, but not sensitive, for the identification of mucocutaneous HSV infection in children. Copyright (c) 2010 Elsevier B.V. All rights reserved.
Linking Illness in Parents to Health Anxiety in Offspring: Do Beliefs about Health Play a Role?
Alberts, Nicole M; Hadjistavropoulos, Heather D; Sherry, Simon B; Stewart, Sherry H
2016-01-01
The cognitive behavioural (CB) model of health anxiety proposes parental illness leads to elevated health anxiety in offspring by promoting the acquisition of specific health beliefs (e.g. overestimation of the likelihood of illness). Our study tested this central tenet of the CB model. Participants were 444 emerging adults (18-25-years-old) who completed online measures and were categorized into those with healthy parents (n = 328) or seriously ill parents (n = 116). Small (d = .21), but significant, elevations in health anxiety, and small to medium (d = .40) elevations in beliefs about the likelihood of illness were found among those with ill vs. healthy parents. Mediation analyses indicated the relationship between parental illness and health anxiety was mediated by beliefs regarding the likelihood of future illness. Our study incrementally advances knowledge by testing and supporting a central proposition of the CB model. The findings add further specificity to the CB model by highlighting the importance of a specific health belief as a central contributor to health anxiety among offspring with a history of serious parental illness.
MANTIS: a phylogenetic framework for multi-species genome comparisons.
Tzika, Athanasia C; Helaers, Raphaël; Van de Peer, Yves; Milinkovitch, Michel C
2008-01-15
Practitioners of comparative genomics face huge analytical challenges as whole genome sequences and functional/expression data accumulate. Furthermore, the field would greatly benefit from a better integration of this wealth of data with evolutionary concepts. Here, we present MANTIS, a relational database for the analysis of (i) gains and losses of genes on specific branches of the metazoan phylogeny, (ii) reconstructed genome content of ancestral species and (iii) over- or under-representation of functions/processes and tissue specificity of gained, duplicated and lost genes. MANTIS estimates the most likely positions of gene losses on the true phylogeny using a maximum-likelihood function. A user-friendly interface and an extensive query system allow to investigate questions pertaining to gene identity, phylogenetic mapping and function/expression parameters. MANTIS is freely available at http://www.mantisdb.org and constitutes the missing link between multi-species genome comparisons and functional analyses.
The Quantitative Science of Evaluating Imaging Evidence.
Genders, Tessa S S; Ferket, Bart S; Hunink, M G Myriam
2017-03-01
Cardiovascular diagnostic imaging tests are increasingly used in everyday clinical practice, but are often imperfect, just like any other diagnostic test. The performance of a cardiovascular diagnostic imaging test is usually expressed in terms of sensitivity and specificity compared with the reference standard (gold standard) for diagnosing the disease. However, evidence-based application of a diagnostic test also requires knowledge about the pre-test probability of disease, the benefit of making a correct diagnosis, the harm caused by false-positive imaging test results, and potential adverse effects of performing the test itself. To assist in clinical decision making regarding appropriate use of cardiovascular diagnostic imaging tests, we reviewed quantitative concepts related to diagnostic performance (e.g., sensitivity, specificity, predictive values, likelihood ratios), as well as possible biases and solutions in diagnostic performance studies, Bayesian principles, and the threshold approach to decision making. Copyright © 2017 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.
Factors Dancers Associate with their Body Dissatisfaction.
Dantas, Ana García; Alonso, Diana Amado; Sánchez-Miguel, Pedro Antonio; Del Río Sánchez, Carmen
2018-06-01
Body dissatisfaction constitutes an important factor in the development of eating pathologies, particularly among dancers. The aim of this research was to test the factors that dancers identified as relevant to their body dissatisfaction using an exploratory mixed method design. Participants were 369 dancers from two Spanish dance conservatories. Questionnaires assessed body dissatisfaction, abnormal eating attitudes and behaviors, and risk factors to eating disorders in the dance domain. Nine factors were found; the "teacher", the "uniform", and the "mirrors" were the most common. Individuals with a greater likelihood of developing an eating disorder identified teacherś influence as a key factor in their body dissatisfaction. Specifically, ballet dancers were more likely to indicate that teachers were a negative influence compared to students in other dance genres (contemporary, flamenco, and Spanish dance). Programs to reduce negative body image and improve positive body image in dance conservatories are needed, specifically focusing on teachers. Copyright © 2018 Elsevier Ltd. All rights reserved.
Methodological comparisons for antimicrobial resistance surveillance in feedlot cattle
2013-01-01
Background The purpose of this study was to objectively compare methodological approaches that might be utilized in designing an antimicrobial resistance (AMR) surveillance program in beef feedlot cattle. Specifically, four separate comparisons were made to investigate their potential impact on estimates for prevalence of AMR. These included investigating potential differences between 2 different susceptibility testing methods (broth microdilution and disc diffusion), between 2 different target bacteria (non-type-specific E. coli [NTSEC] and Mannheimia haemolytica), between 2 strategies for sampling feces (individual samples collected per rectum and pooled samples collected from the pen floor), and between 2 strategies for determining which cattle to sample (cattle that were culture-positive for Mannheimia haemolytica and those that were culture-negative). Results Comparing two susceptibility testing methods demonstrated differences in the likelihood of detecting resistance between automated disk diffusion (BioMIC®) and broth microdilution (Sensititre®) for both E. coli and M. haemolytica. Differences were also detected when comparing resistance between two bacterial organisms within the same cattle; there was a higher likelihood of detecting resistance in E. coli than in M. haemolytica. Differences in resistance prevalence were not detected when using individual animal or composite pen sampling strategies. No differences in resistance prevalences were detected in E. coli recovered from cattle that were culture-positive for M. haemolytica compared to those that were culture-negative, suggesting that sampling strategies which targeted recovery of E. coli from M. haemolytica-positive cattle would not provide biased results. Conclusions We found that for general purposes, the susceptibility test selected for AMR surveillance must be carefully chosen considering the purpose of the surveillance since the ability to detect resistance appears to vary between these tests depending upon the population where they are applied. Continued surveillance of AMR in M. haemolytica recovered by nasopharyngeal swab is recommended if monitoring an animal health pathogen is an objective of the surveillance program as results of surveillance using fecal E. coli cannot be extrapolated to this important respiratory pathogen. If surveillance of E. coli was pursued in the same population, study populations could target animals that were culture-positive for M. haemolytica without biasing estimates for AMR in E. coli. Composite pen-floor sampling or sampling of individuals per-rectum could possibly be used interchangeably for monitoring resistance in E. coli. PMID:24144185
Hogg, K; Dawson, D; Mackway‐Jones, K
2006-01-01
Objectives To measure the diagnostic accuracy of computerised strain gauge plethysmography in the diagnosis of pulmonary embolism (PE). Methods Two researchers prospectively recruited 425 patients with pleuritic chest pain presenting to the emergency department (ED). Lower limb computerised strain gauge plethysmography was performed in the ED. All patients underwent an independent reference standard diagnostic algorithm to establish the presence or absence of PE. A low modified Wells' clinical probability combined with a normal D‐dimer excluded PE. All others required diagnostic imaging with PIOPED interpreted ventilation perfusion scanning and/or computerised tomography (CT) pulmonary angiography. Patients with a nondiagnostic CT had digital subtraction pulmonary angiography. All patients were followed up clinically for 3 months. Results The sensitivity of computerised strain gauge plethysmography was 33.3% (95% confidence interval (CI) 16.3 to 56.2%) and specificity 64.1% (95% CI 59.0 to 68.8%). The negative likelihood ratio was 1.04 (95% CI 0.68 to 1.33) and positive likelihood ratio 0.93 (95% CI 0.45 to 1.60). Conclusions Lower limb computerised strain gauge plethysmography does not aid in the diagnosis of PE. PMID:16439734
Rape myth acceptance and rape acknowledgment: The mediating role of sexual refusal assertiveness.
Newins, Amie R; Wilson, Laura C; White, Susan W
2018-05-01
Unacknowledged rape, defined as when an individual experiences an event that meets a legal or empirical definition of rape but the individual does not label it as such, is prevalent. Research examining predictors of rape acknowledgment is needed. Sexual assertiveness may be an important variable to consider, as an individual's typical behavior during sexual situations may influence rape acknowledgment. To assess the indirect effect of rape myth acceptance on rape acknowledgment through sexual refusal assertiveness, an online survey of 181 female rape survivors was conducted. The indirect effects of two types of rape myths (He didn't mean to and Rape is a deviant event) were significant and positive. Specifically, acceptance of these two rape myths was negatively related to sexual refusal assertiveness, which was negatively associated with likelihood of rape acknowledgment. The results of this study indicate that sexual refusal assertiveness is associated with lower likelihood of rape acknowledgment among rape survivors. As a result, it appears that, under certain circumstances, women high in rape myth acceptance may be more likely to acknowledge rape when it results in decreased sexual refusal assertiveness. Copyright © 2018 Elsevier B.V. All rights reserved.
THE DIAGNOSTIC ACCURACY OF THE LEVER SIGN FOR DETECTING ANTERIOR CRUCIATE LIGAMENT INJURY
Anderson, Amanda; Watson, Seth; Dimeff, Robert J.
2017-01-01
Background An alternative physical examination procedure for evaluating the integrity of the anterior cruciate ligament (ACL) has been proposed in the literature but has not been validated in a broad population of patients with a symptomatic complaint of knee pain for its diagnostic value. Purpose To investigate the diagnostic accuracy of the Lever Sign to detect ACL tears and compare the results to Lachman testing in both supine and prone positions. Study design Prospective, blinded, diagnostic accuracy study. Methods Sixty-two consecutive patients with a complaint of knee pain were independently evaluated for the status of the ACL's integrity with the Lever Sign and the Lachman test in a prone and supine by a blinded examiner before any other diagnostic assessments were completed. Results Twenty-four of the 60 patients included in the analysis had a torn ACL resulting in a prevalence of 40%. The sensitivity of the Lever Sign, prone, and supine Lachman tests were 38, 83, and 67 % respectively and the specificity was 72, 89, and 97% resulting in positive likelihood ratios of 1.4, 7.5, and 24 and negative likelihood ratios of 0.86, 0.19, and 0.34 respectively. The positive predictive values were 47, 83, and 94% and the negative predictive values were 63, 89, and 81% respectively. The diagnostic odds ratios were 1.6, 40, and 70 with a number needed to diagnose of 10.3, 1.4, and 1.6 respectively. Conclusions The results of this study suggest that Lever Sign, in isolation, does not accurately detect the status of the ACL. During the clinical examination, the Lever Sign should be used as an adjunct to the gold standard assessment technique of anterior tibial translation assessment as employed in the Lachman tests in either prone or supine position. Level of Evidence 2 PMID:29234557
Antecedents of Psychological Contract Breach: The Role of Job Demands, Job Resources, and Affect
Vantilborgh, Tim; Bidee, Jemima; Pepermans, Roland; Griep, Yannick; Hofmans, Joeri
2016-01-01
While it has been shown that psychological contract breach leads to detrimental outcomes, relatively little is known about factors leading to perceptions of breach. We examine if job demands and resources predict breach perceptions. We argue that perceiving high demands elicits negative affect, while perceiving high resources stimulates positive affect. Positive and negative affect, in turn, influence the likelihood that psychological contract breaches are perceived. We conducted two experience sampling studies to test our hypotheses: the first using daily surveys in a sample of volunteers, the second using weekly surveys in samples of volunteers and paid employees. Our results confirm that job demands and resources are associated with negative and positive affect respectively. Mediation analyses revealed that people who experienced high job resources were less likely to report psychological contract breach, because they experienced high levels of positive affect. The mediating role of negative affect was more complex, as it increased the likelihood to perceive psychological contract breach, but only in the short-term. PMID:27171275
Antecedents of Psychological Contract Breach: The Role of Job Demands, Job Resources, and Affect.
Vantilborgh, Tim; Bidee, Jemima; Pepermans, Roland; Griep, Yannick; Hofmans, Joeri
2016-01-01
While it has been shown that psychological contract breach leads to detrimental outcomes, relatively little is known about factors leading to perceptions of breach. We examine if job demands and resources predict breach perceptions. We argue that perceiving high demands elicits negative affect, while perceiving high resources stimulates positive affect. Positive and negative affect, in turn, influence the likelihood that psychological contract breaches are perceived. We conducted two experience sampling studies to test our hypotheses: the first using daily surveys in a sample of volunteers, the second using weekly surveys in samples of volunteers and paid employees. Our results confirm that job demands and resources are associated with negative and positive affect respectively. Mediation analyses revealed that people who experienced high job resources were less likely to report psychological contract breach, because they experienced high levels of positive affect. The mediating role of negative affect was more complex, as it increased the likelihood to perceive psychological contract breach, but only in the short-term.
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.
Predictors of short-term outcome to exercise and manual therapy for people with hip osteoarthritis.
French, Helen P; Galvin, Rose; Cusack, Tara; McCarthy, Geraldine M
2014-01-01
Physical therapy for hip osteoarthritis (OA) has shown short-term effects but limited long-term benefit. There has been limited research, with inconsistent results, in identifying prognostic factors associated with a positive response to physical therapy. The purpose of this study was to identify potential predictors of response to physical therapy (exercise therapy [ET] with or without adjunctive manual therapy [MT]) for hip OA based on baseline patient-specific and clinical characteristics. A prognostic study was conducted. Secondary analysis of data from a multicenter randomized controlled trial (RCT) (N=131) that evaluated the effectiveness of ET and ET+MT for hip OA was undertaken. Treatment response was defined using OMERACT/OARSI responder criteria. Ten baseline measures were used as predictor variables. Regression analyses were undertaken to identify predictors of outcome. Discriminative ability (sensitivity, specificity, and likelihood ratios) of significant variables was calculated. The RCT results showed no significant difference in most outcomes between ET and ET+MT at 9 and 18 weeks posttreatment. Forty-six patients were classified as responders at 9 weeks, and 36 patients were classified as responders at 18 weeks. Four baseline variables were predictive of a positive outcome at 9 weeks: male sex, pain with activity (<6/10), Western Ontario and McMaster Universities Osteoarthritis Index physical function subscale score (<34/68), and psychological health (Hospital Anxiety and Depression Scale score <9/42). No predictor variables were identified at the 18-week follow-up. Prognostic accuracy was fair for all 4 variables (sensitivity=0.5-0.58, specificity=0.57-0.72, likelihood ratios=1.25-1.77), indicating fair discriminative ability at predicting treatment response. The short-term follow-up limits the interpretation of results, and the low number of identified responders may have resulted in possible overfitting of the predictor model. The authors were unable to identify baseline variables in patients with hip OA that indicate those most likely to respond to treatment due to low discriminative ability. Further validation studies are needed to definitively define the best predictors of response to physical therapy in people with hip OA.
Interpretation of diagnostic data: 5. How to do it with simple maths.
1983-11-01
The use of simple maths with the likelihood ratio strategy fits in nicely with our clinical views. By making the most out of the entire range of diagnostic test results (i.e., several levels, each with its own likelihood ratio, rather than a single cut-off point and a single ratio) and by permitting us to keep track of the likelihood that a patient has the target disorder at each point along the diagnostic sequence, this strategy allows us to place patients at an extremely high or an extremely low likelihood of disease. Thus, the numbers of patients with ultimately false-positive results (who suffer the slings of labelling and the arrows of needless therapy) and of those with ultimately false-negative results (who therefore miss their chance for diagnosis and, possibly, efficacious therapy) will be dramatically reduced. The following guidelines will be useful in interpreting signs, symptoms and laboratory tests with the likelihood ratio strategy: Seek out, and demand from the clinical or laboratory experts who ought to know, the likelihood ratios for key symptoms and signs, and several levels (rather than just the positive and negative results) of diagnostic test results. Identify, when feasible, the logical sequence of diagnostic tests. Estimate the pretest probability of disease for the patient, and, using either the nomogram or the conversion formulas, apply the likelihood ratio that corresponds to the first diagnostic test result. While remembering that the resulting post-test probability or odds from the first test becomes the pretest probability or odds for the next diagnostic test, repeat the process for all the pertinent symptoms, signs and laboratory studies that pertain to the target disorder. However, these combinations may not be independent, and convergent diagnostic tests, if treated as independent, will combine to overestimate the final post-test probability of disease. You are now far more sophisticated in interpreting diagnostic tests than most of your teachers. In the last part of our series we will show you some rather complex strategies that combine diagnosis and therapy, quantify our as yet nonquantified ideas about use, and require the use of at least a hand calculator.
Interpretation of diagnostic data: 5. How to do it with simple maths.
1983-01-01
The use of simple maths with the likelihood ratio strategy fits in nicely with our clinical views. By making the most out of the entire range of diagnostic test results (i.e., several levels, each with its own likelihood ratio, rather than a single cut-off point and a single ratio) and by permitting us to keep track of the likelihood that a patient has the target disorder at each point along the diagnostic sequence, this strategy allows us to place patients at an extremely high or an extremely low likelihood of disease. Thus, the numbers of patients with ultimately false-positive results (who suffer the slings of labelling and the arrows of needless therapy) and of those with ultimately false-negative results (who therefore miss their chance for diagnosis and, possibly, efficacious therapy) will be dramatically reduced. The following guidelines will be useful in interpreting signs, symptoms and laboratory tests with the likelihood ratio strategy: Seek out, and demand from the clinical or laboratory experts who ought to know, the likelihood ratios for key symptoms and signs, and several levels (rather than just the positive and negative results) of diagnostic test results. Identify, when feasible, the logical sequence of diagnostic tests. Estimate the pretest probability of disease for the patient, and, using either the nomogram or the conversion formulas, apply the likelihood ratio that corresponds to the first diagnostic test result. While remembering that the resulting post-test probability or odds from the first test becomes the pretest probability or odds for the next diagnostic test, repeat the process for all the pertinent symptoms, signs and laboratory studies that pertain to the target disorder. However, these combinations may not be independent, and convergent diagnostic tests, if treated as independent, will combine to overestimate the final post-test probability of disease. You are now far more sophisticated in interpreting diagnostic tests than most of your teachers. In the last part of our series we will show you some rather complex strategies that combine diagnosis and therapy, quantify our as yet nonquantified ideas about use, and require the use of at least a hand calculator. PMID:6671182
Parents’ perceptions of provider communication regarding adolescent vaccines
Dempsey, Amanda F.; Pyrzanowski, Jennifer; Lockhart, Steven; Campagna, Elizabeth; Barnard, Juliana; O'Leary, Sean T.
2016-01-01
ABSTRACT Strong provider recommendations for adolescent vaccines are critical for achieving high vaccination levels. However, little is known about parents’ preferred provider communication strategies for adolescent vaccines in general, and for human papillomavirus (HPV) vaccines specifically. We performed a cross-sectional survey of 800 parents of 9-14 year olds in April 2014 to assess current adolescent vaccine communication practices by providers, parents’ preferred HPV vaccine-specific communication strategies, and the association of these two outcomes with experiential, attitudinal and demographic characteristics. Among the 356 parents in the study (response rate 48%), HPV vaccines were reported as less likely to have been “very strongly” recommended by their adolescent’s provider (39%) than other adolescent-targeted vaccines (45%-59%, <0.05 for all comparisons). Receiving a very strong recommendation for HPV vaccines was associated with a higher likelihood of vaccine receipt (71% versus 39%, p<0.001), or among those not yet vaccinated, increased likelihood of positive vaccination intentions (82% vs. 60%, p = 0.015). Nearly all parents (87%) reported that, if available, they would use a website providing personalized HPV vaccine-related materials before their adolescent’s next check-up, and other technology-based communications were also endorsed by the majority of parents. From these data we conclude that parents received weaker recommendations for HPV vaccines than other adolescent vaccines, and that most parents want additional HPV vaccine-related materials, preferably delivered using a variety of technology-based modalities which is not their providers’ current practice. PMID:27078515
2013-01-01
Background Achieving Millennium Development Goal 4 is dependent on significantly reducing neonatal mortality. Low birth weight is an underlying factor in most neonatal deaths. In developing countries the missed opportunity for providing life saving care is mainly a result of failure to identify low birth weight newborns. This study aimed at identifying a reliable anthropometric measurement for screening low birth weight and determining an operational cut-off point in the Uganda setting. This simple measurement is required because of lack of weighing scales in the community, and sometimes in the health facilities. Methods This was a hospital-based cross-sectional study. Two midwives weighed 706 newborns and measured their foot length, head, chest, thigh and mid-upper arm circumferences within 24 hours after birth. Data was analysed using STATA version 10.0. Correlation with birth weight using Pearson’s correlation coefficient and Receiver Operating Characteristics curve analysis were done to determine the measure that best predicts birth weight. Sensitivity and specificity were calculated for a range of measures to obtain operational cut-off points; and Likelihood Ratios and Diagnostic Odds Ratio were determined for each cut-off point. Results Birth weights ranged from 1370–5350 grams with a mean of 3050 grams (SD 0.53) and 85 (12%) babies weighed less than 2500 grams. All anthropometric measurements had a positive correlation with birth weight, with foot length showing the strongest (r = 0.76) and thigh circumference the weakest (r = 0.62) correlations. Foot length had the highest predictive value for low birth weight (AUC = 0.97) followed by mid-upper arm circumference (AUC = 0.94). Foot length and chest circumference had the highest sensitivity (94%) and specificity (90%) respectively for screening low birth weight babies at the selected cut-off points. Chest circumference had a significantly higher positive likelihood ratio (8.7) than any other measure, and foot length had the lowest negative likelihood ratio. Chest circumference and foot length had diagnostic odds ratios of 97% and 77% respectively. Foot length was easier to measure and it involved minimal exposure of the baby to cold. A cut-off of foot length 7.9 cm had sensitivity of 94% and specificity of 83% for predicting low birth weight. Conclusions This study suggests foot length as the most appropriate predictor for low birth weight in comparison to chest, head, mid-upper arm and thigh circumference in the Uganda setting. Use of low cost and easy to use tools to identify low birth weight babies by village health teams could support community efforts to save newborns. PMID:23587297
Measures of accuracy and performance of diagnostic tests.
Drobatz, Kenneth J
2009-05-01
Diagnostic tests are integral to the practice of veterinary cardiology, any other specialty, and general veterinary medicine. Developing and understanding diagnostic tests is one of the cornerstones of clinical research. This manuscript describes the diagnostic test properties including sensitivity, specificity, predictive value, likelihood ratio, receiver operating characteristic curve. Review of practical book chapters and standard statistics manuscripts. Diagnostics such as sensitivity, specificity, predictive value, likelihood ratio, and receiver operating characteristic curve are described and illustrated. Basic understanding of how diagnostic tests are developed and interpreted is essential in reviewing clinical scientific papers and understanding evidence based medicine.
Galvan, Frank H; Bogart, Laura M; Wagner, Glenn J; Klein, David J; Chen, Ying-Tung
2014-06-01
HIV-positive Latino men have been found to have poorer medication adherence compared to Whites. This study sought to identify how cultural conceptualisations of masculinity are associated with self-reported medication adherence among Latino men. A total of 208 HIV-positive men reported the number of doses of antiretroviral medication missed in the previous seven days (dichotomised at 100% adherence versus less). Conceptualisations of masculinity consisted of traditional machismo (e.g., power and aggressive attitudes, which are normally associated with negative stereotypes of machismo) and caballerismo (e.g., fairness, respect for elders and the importance of family). Multivariate logistic regression was used to identify factors associated with adherence. The mean adherence was 97% (SD = 6.5%; range = 57-100%). In all, 77% of the participants reported 100% adherence in the previous seven days. Caballerismo was associated with a greater likelihood (OR = 1.77; 95% CI: 1.08-2.92; p = 0.03) and machismo with a lower likelihood (OR = 0.60; 95% CI: 0.38-0.95; p = 0.03) of medication adherence. In addition, higher medication side-effects were found to be associated with a lower likelihood (OR = 0.59; 95% CI: 0.43-0.81; p = 0.001) of medication adherence. These findings reinforce the importance of identifying cultural factors that may affect medication adherence among HIV-positive Latino men resident in the USA.
The complexity of selection at the major primate beta-defensin locus.
Semple, Colin A M; Maxwell, Alison; Gautier, Philippe; Kilanowski, Fiona M; Eastwood, Hayden; Barran, Perdita E; Dorin, Julia R
2005-05-18
We have examined the evolution of the genes at the major human beta-defensin locus and the orthologous loci in a range of other primates and mouse. For the first time these data allow us to examine selective episodes in the more recent evolutionary history of this locus as well as the ancient past. We have used a combination of maximum likelihood based tests and a maximum parsimony based sliding window approach to give a detailed view of the varying modes of selection operating at this locus. We provide evidence for strong positive selection soon after the duplication of these genes within an ancestral mammalian genome. Consequently variable selective pressures have acted on beta-defensin genes in different evolutionary lineages, with episodes both of negative, and more rarely positive selection, during the divergence of primates. Positive selection appears to have been more common in the rodent lineage, accompanying the birth of novel, rodent-specific beta-defensin genes. These observations allow a fuller understanding of the evolution of mammalian innate immunity. In both the rodent and primate lineages, sites in the second exon have been subject to positive selection and by implication are important in functional diversity. A small number of sites in the mature human peptides were found to have undergone repeated episodes of selection in different primate lineages. Particular sites were consistently implicated by multiple methods at positions throughout the mature peptides. These sites are clustered at positions predicted to be important for the specificity of the antimicrobial or chemoattractant properties of beta-defensins. Surprisingly, sites within the prepropeptide region were also implicated as being subject to significant positive selection, suggesting previously unappreciated functional significance for this region. Identification of these putatively functional sites has important implications for our understanding of beta-defensin function and for novel antibiotic design.
Petrova, Mariya; Wyman, Peter A; Schmeelk-Cone, Karen; Pisani, Anthony R
2015-12-01
Developing science-based communication guidance and positive-themed messages for suicide prevention are important priorities. Drawing on social learning and elaboration likelihood models, we designed and tested two positive-focused presentations by high school peer leaders delivered in the context of a suicide prevention program (Sources of Strength). Thirty-six classrooms in four schools (N = 706 students) were randomized to (1) peer leader modeling of healthy coping, (2) peer leader modeling plus audience involvement to identify trusted adults, or (3) control condition. Students' attitudes and norms were assessed by immediate post-only assessments. Exposure to either presentation enhanced positive coping attitudes and perceptions of adult support. Students who reported suicide ideation in the past 12 months benefited more than nonsuicidal students. Beyond modeling alone, audience involvement modestly enhanced expectations of adult support, congruent with the elaboration likelihood model. Positive peer modeling is a promising alternative to communications focused on negative consequences and directives and may enhance social-interpersonal factors linked to reduced suicidal behaviors. © 2015 The American Association of Suicidology.
Petrova, Mariya; Wyman, Peter A.; Schmeelk-Cone, Karen; Pisani, Anthony R.
2015-01-01
Developing science-based communication guidance and positive-themed messages for suicide prevention are important priorities. Drawing on social learning and elaboration likelihood models, we designed and tested two positive-focused presentations by high school peer leaders delivered in the context of a suicide prevention program (Sources of Strength). Thirty six classrooms in four schools (N=706 students) were randomized to: (a) peer leader modeling of healthy coping, (b) peer leader modeling plus audience involvement to identify trusted adults, or (c) control condition. Students’ attitudes and norms were assessed by immediate post-only assessments. Exposure to either presentation enhanced positive coping attitudes and perceptions of adult support. Students who reported suicide ideation in the past 12 months benefited more than non-suicidal students. Beyond modeling alone, audience involvement modestly enhanced expectations of adult support, congruent with the elaboration likelihood model. Positive peer modeling is a promising alternative to communications focused on negative consequences and directives and may enhance social-interpersonal factors linked to reduced suicidal behaviors. PMID:25692382
When you see it, let it be: Urgency, mindfulness and adolescent substance use.
Robinson, Joanna M; Ladd, Benjamin O; Anderson, Kristen G
2014-06-01
The emotion-based domains of impulsivity, positive and negative urgency, are facets that have garnered attention due to their associations with substance use, and mindfulness based strategies have shown promise in reducing substance use in adults. The aim of the current study was to examine relations among urgency, mindfulness, and substance use in adolescence. Cross-sectional data were collected from students (N=1,051) at a large, private high school in the Pacific Northwest. Both positive and negative urgency were uniquely associated with greater likelihood of lifetime and current alcohol use; only positive urgency predicted lifetime marijuana use. Mindfulness was associated with a lower likelihood of lifetime alcohol or marijuana use. Interactions between urgency and mindfulness were not supported. Our findings highlight the need to explore relations among baseline mindfulness, skills based mindfulness, and personality in adolescent alcohol and other drug use. Copyright © 2014 Elsevier Ltd. All rights reserved.
When you see it, let it be: Urgency, mindfulness and adolescent substance use
Robinson, Joanna M.; Ladd, Benjamin O.; Anderson, Kristen G.
2015-01-01
The emotion-based domains of impulsivity, positive and negative urgency, are facets that have garnered attention due to their associations with substance use, and mindfulness based strategies have shown promise in reducing substance use in adults. The aim of the current study was to examine relations among urgency, mindfulness, and substance use in adolescence. Cross-sectional data were collected from students (N = 1,051) at a large, private high school in the Pacific Northwest. Both positive and negative urgency were uniquely associated with greater likelihood of lifetime and current alcohol use; only positive urgency predicted lifetime marijuana use. Mindfulness was associated with a lower likelihood of lifetime alcohol or marijuana use. Interactions between urgency and mindfulness were not supported. Our findings highlight the need to explore relations among baseline mindfulness, skills based mindfulness, and personality in adolescent alcohol and other drug use. PMID:24629324
Forecasting drought risks for a water supply storage system using bootstrap position analysis
Tasker, Gary; Dunne, Paul
1997-01-01
Forecasting the likelihood of drought conditions is an integral part of managing a water supply storage and delivery system. Position analysis uses a large number of possible flow sequences as inputs to a simulation of a water supply storage and delivery system. For a given set of operating rules and water use requirements, water managers can use such a model to forecast the likelihood of specified outcomes such as reservoir levels falling below a specified level or streamflows falling below statutory passing flows a few months ahead conditioned on the current reservoir levels and streamflows. The large number of possible flow sequences are generated using a stochastic streamflow model with a random resampling of innovations. The advantages of this resampling scheme, called bootstrap position analysis, are that it does not rely on the unverifiable assumption of normality and it allows incorporation of long-range weather forecasts into the analysis.
Dasgupta, Subhankar; Dasgupta, Shyamal; Sharma, Partha Pratim; Mukherjee, Amitabha; Ghosh, Tarun Kumar
2011-11-01
To investigate the effect of oral progesterone on the accuracy of imaging studies performed to detect endometrial pathology in comparison to hysteroscopy-guided biopsy in perimenopausal women on progesterone treatment for abnormal uterine bleeding. The study population comprised of women aged 40-55 years with complaints of abnormal uterine bleeding who were also undergoing oral progesterone therapy. Women with a uterus ≥ 12 weeks' gestation size, previous abnormal endometrial biopsy, cervical lesion on speculum examination, abnormal Pap smear, active pelvic infection, adnexal mass on clinical examination or during ultrasound scan and a positive pregnancy test were excluded. A transvaginal ultrasound followed by saline infusion sonography were done. On the following day, a hysteroscopy followed by a guided biopsy of the endometrium or any endometrial lesion was performed. Comparison between the results of the imaging study with the hysteroscopy and guided biopsy was done. The final analysis included 83 patients. For detection of overall pathology, polyp and fibroid transvaginal ultrasound had a positive likelihood ratio of 1.65, 5.45 and 5.4, respectively, and a negative likelihood ratio of 0.47, 0.6 and 0.43, respectively. For detection of overall pathology, polyp and fibroid saline infusion sonography had a positive likelihood ratio of 4.4, 5.35 and 11.8, respectively, and a negative likelihood ratio of 0.3, 0.2 and 0.15, respectively. In perimenopausal women on oral progesterone therapy for abnormal uterine bleeding, imaging studies cannot be considered as an accurate method for diagnosing endometrial pathology when compared to hysteroscopy and guided biopsy. © 2011 The Authors. Journal of Obstetrics and Gynaecology Research © 2011 Japan Society of Obstetrics and Gynecology.
Loh, Jane; Kennedy, Mary Clare; Wood, Evan; Kerr, Thomas; Marshall, Brandon; Parashar, Surita; Montaner, Julio; Milloy, M-J
2016-11-01
Homelessness is common among people who use drugs (PWUD) and, for those living with HIV/AIDS, an important contributor to sub-optimal HIV treatment outcomes. This study aims to investigate the relationship between the duration of homelessness and the likelihood of plasma HIV-1 RNA viral load (VL) non-detectability among a cohort of HIV-positive PWUD. We used data from the ACCESS study, a long-running prospective cohort study of HIV-positive PWUD linked to comprehensive HIV clinical records including systematic plasma HIV-1 RNA VL monitoring. We estimated the longitudinal relationship between the duration of homelessness and the likelihood of exhibiting a non-detectable VL (i.e., <500 copies/mL plasma) using generalized linear mixed-effects modelling. Between May 1996 and June 2014, 922 highly active antiretroviral therapy-exposed participants were recruited and contributed 8188 observations. Of these, 4800 (59%) were characterized by non-detectable VL. Participants reported they were homeless in 910 (11%) interviews (median: six months, interquartile range: 6-12 months). A longer duration of homelessness was associated with lower odds of VL non-detectability (adjusted odds ratio = 0.71 per six-month period of homelessness, 95% confidence interval: 0.60-0.83) after adjustment for age, ancestry, drug use patterns, engagement in addiction treatment, and other potential confounders. Longer durations of episodes of homelessness in this cohort of HIV-positive illicit drug users were associated with a lower likelihood of plasma VL non-detectability. Our findings suggest that interventions that seek to promptly house homeless individuals, such as Housing First approaches, might assist in maximizing the clinical and public health benefits of antiretroviral therapy among people living with HIV/AIDS.
Alvaro-Meca, Alejandro; Palomares-Sancho, Ines; Diaz, Asuncion; Resino, Rosa; De Miguel, Angel Gil; Resino, Salvador
2015-01-01
Introduction Specific environmental factors may play a role in the development of Pneumocystis pneumonia (PCP) in HIV-positive patients. The aim of this study was to estimate the PCP incidence and mortality in hospitalized HIV-positive patients in Spain during the combination antiretroviral therapy (cART) era (1997 to 2011), as well as to analyze the climatological factors and air pollution levels in relation to hospital admissions and deaths. Methods We carried out a retrospective study. Data were collected from the National Hospital Discharge Database and the State Meteorological Agency of Spain. A case-crossover analysis was applied to identify environmental risk factors related to hospitalizations and deaths. For each patient, climatic factors and pollution levels were assigned based on readings from the nearest meteorological station to his or her postal code. Results There were 13,139 new PCP diagnoses and 1754 deaths in hospitalized HIV-positive patients from 1997 to 2011. The PCP incidence (events per 1000 person-years) dropped from 11.6 in 1997 to 2000, to 5.4 in 2004 to 2011 (p<0.001). The mortality (events per 10,000 person-years) also decreased from 14.3 in 1997 to 2000, to 7.5 in 2004 to 2011 (p<0.001). Most hospital admissions and deaths occurred in the winter season and the fewest occurred in the summer, overlapping respectively with the lowest and highest temperatures of the year in Spain. Moreover, lower temperatures prior to PCP admission, as well as higher concentrations of NO2 and particulate matter up to 10 m in size (PM10) at the time of admission were associated with higher likelihoods of hospital admission due to PCP when two weeks, one month, 1.5 months or two months were used as controls (p<0.01). Furthermore, higher concentrations of ozone at one month (p=0.007), 1.5 months (p<0.001) and two months (p=0.006) prior to admission were associated with higher likelihoods of hospital admission with PCP. For PCP-related deaths, lower temperatures prior to admission and higher concentrations of atmospheric PM10 at the time of admission were related to higher likelihood of death when two weeks, one month and 1.5 months were used as controls (p<0.05). Conclusions PCP was a significant health problem in the cART era (1997 to 2011), and PCP epidemiology was adversely influenced by colder climatological factors and higher ambient air pollution levels. PMID:25997453
A preliminary study of longitudinal neuroadaptation associated with recovery from addiction.
Forster, Sarah E; Finn, Peter R; Brown, Joshua W
2016-11-01
Few studies have explored longitudinal change in event-related brain responses during early recovery from addiction. Moreover, existing findings yield evidence of both increased and decreased signaling within reward and control centers over time. The current study explored reward- and control-related signals in a risky decision-making task and specifically investigated parametric modulations of the BOLD signal, rather than signal magnitude alone. It was hypothesized that risk-related signals during decision-making and outcome evaluation would reflect recovery and that change in specific signals would correspond with improved treatment outcomes. Twenty-one substance dependent individuals were recruited upon enrollment in community-based substance use treatment programs, wherein they received treatment-as-usual. Participants completed functional neuroimaging assessments at baseline and 3-month follow-up while performing the Balloon Analogue Risk Task (BART). Risk- and reward-sensitive signals were identified using parametric modulators. Substance use was tracked throughout the 3-month study interval using the timeline follow-back procedure. Longitudinal contrasts of parametric modulators suggested improved formation of risk-informed outcome expectations at follow-up. Specifically, a greater response to high risk (low-likelihood) positive feedback was identified in caudal anterior cingulate cortex (ACC) and a greater response to low risk (low-likelihood) negative feedback was identified in caudal ACC and inferior frontal gyrus. In addition, attenuation of a ventromedial prefrontal cortex (vmPFC) "reward-seeking" signal (i.e., increasing response with greater reward) during risky decisions at follow-up was associated with less substance use during the study interval. Changes in risk- and reward-related signaling in ACC/vmPFC appear to reflect recovery and may support sobriety. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.
Li, Bo; Sun, Zhiqiang; Li, Xiaohan; Li, Xiaoxi; Wang, Han; Chen, Weijiao; Chen, Peng; Qiao, Mengran; Mao, Yuanli
2017-04-01
There have been many inconsistent reports about the performance of histidine-rich protein 2 (HRP2) and lactate dehydrogenase (LDH) antigens as rapid diagnostic tests (RDTs) for the diagnosis of past Plasmodium falciparum infections. This meta-analysis was performed to determine the performance of pfHRP2 versus pLDH antigen RDTs in the detection of P. falciparum . After a systematic review of related studies, Meta-DiSc 1.4 software was used to calculate the pooled sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), and diagnostic odds ratio (DOR). Forest plots and summary receiver operating characteristic curve (SROC) analysis were used to summarize the overall test performance. Fourteen studies which met the inclusion criteria were included in the meta-analysis. The summary performances for pfHRP2- and pLDH-based tests in the diagnosis of P. falciparum infections were as follows: pooled sensitivity, 96.3% (95.8-96.7%) vs. 82.6% (81.7-83.5%); specificity, 86.1% (85.3-86.8%) vs. 95.9% (95.4-96.3%); diagnostic odds ratio (DOR), 243.31 (97.679-606.08) vs. 230.59 (114.98-462.42); and area under ROCs, 0.9822 versus 0.9849 (all p < 0.001). The two RDTs performed satisfactorily for the diagnosis of P. falciparum , but the pLDH tests had higher specificity, whereas the pfHRP2 tests had better sensitivity. The pfHRP2 tests had slightly greater accuracy compared to the pLDH tests. A combination of both antigens might be a more reliable approach for the diagnosis of malaria.
Katz, Brian S.; McMullan, Jason T.; Sucharew, Heidi; Adeoye, Opeolu; Broderick, Joseph P.
2015-01-01
Background and Purpose We derived and validated the Cincinnati Prehospital Stroke Severity Scale (CPSSS) to identify patients with severe strokes and large vessel occlusion (LVO). Methods CPSSS was developed with regression tree analysis, objectivity, anticipated ease in administration by EMS personnel, and the presence of cortical signs. We derived and validated the tool using the two NINDS t-PA Stroke Study trials and IMS III Trial cohorts, respectively, to predict severe stroke [NIH stroke scale (NIHSS) ≥15] and LVO. Standard test characteristics were determined and receiver operator curves were generated and summarized by the area under the curve (AUC). Results CPSSS score ranges from 0-4; composed and scored by individual NIHSS items: 2 points for presence of conjugate gaze (NIHSS ≥1); 1 point for presence of arm weakness (NIHSS ≥2); and 1 point for presence abnormal level of consciousness (LOC) commands and questions (NIHSS LOC ≥1 each). In the derivation set, CPSSS had an AUC of 0.89; score ≥2 was 89% sensitive and 73% specific in identifying NIHSS ≥15. Validation results were similar with an AUC of 0.83; score ≥2 was 92% sensitive, 51% specific, a positive likelihood ratio (PLR) of 3.3 and a negative likelihood ratio (NLR) of 0.15 in predicting severe stroke. For 222/303 IMS III subjects with LVO, CPSSS had an AUC of 0.67; a score ≥2 was 83% sensitive, 40% specific, PLR of 1.4, and NLR of 0.4 in predicting LVO. Conclusions CPSSS can identify stroke patients with NIHSS ≥15 and LVO. Prospective prehospital validation is warranted. PMID:25899242
Bustamante, Marco; Devesa, Francesc; Borghol, Abdul; Ortuño, Juan; Ferrando, Maria Jose
2002-07-01
Endoscopic follow-up study of gastric ulcers has been recommended routinely because of the possibility that a gastric neoplasm will be missed in the initial endoscopy. Some authors, most of them reporting data from areas of low gastric carcinoma incidence, have questioned this policy because of the low numbers of curable cancers detected and the high cost of such a program. To assess the accuracy of endoscopy diagnosis of gastric ulcers, and to evaluate the efficacy and cost of a gastric ulcer follow-up endoscopic program in an area with an intermediate incidence rate of gastric cancer. A retrospective study was used to identify all the gastroscopies in which a gastric ulcer had been diagnosed during a 6-year period. The endoscopic impression was compared with the histologic diagnosis, sensitivity, specificity, positive and negative predictive values, and the likelihood ratio. Patients who completed a follow-up program also were reviewed. For each neoplasm discovered, the number of endoscopies and global cost were calculated. In the 741 gastroscopies performed, 547 gastric ulcers were diagnosed in 529 patients. Biopsies were taken in 330 patients, in whom 341 gastric ulcers were found. At the index endoscopy, 41 gastric neoplasms (12.4%) were diagnosed. The accuracy of endoscopic malignancy diagnosis was as follows: positive predictive value of 0.68, negative predictive value of 0.98, sensitivity of 0.82, and specificity of 0.95. The likelihood ratio was 16. A total of 117 patients completed the follow-up program. Three new cases of gastric cancer (2.6%) were identified. In these three cases, the initial opinion of the endoscopist was uncertain. In the authors' experience, the cost of each gastric cancer diagnosed has been $4.653 (U.S. dollars). The endoscopic impression correlates with the histologic diagnosis even in a area of intermediate gastric cancer incidence. Endoscopic follow-up study may be restricted to cases of uncertain or malignant endoscopic impression.
Yavin, Daniel; Luu, Judy; James, Matthew T; Roberts, Derek J; Sutherland, Garnette R; Jette, Nathalie; Wiebe, Samuel
2014-09-01
Because clinical examination and imaging may be unreliable indicators of intracranial hypertension, intraocular pressure (IOP) measurement has been proposed as a noninvasive method of diagnosis. The authors conducted a systematic review and meta-analysis to determine the correlation between IOP and intracranial pressure (ICP) and the diagnostic accuracy of IOP measurement for detection of intracranial hypertension. The authors searched bibliographic databases (Ovid MEDLINE, Ovid EMBASE, and the Cochrane Central Register of Controlled Trials) from 1950 to March 2013, references of included studies, and conference abstracts for studies comparing IOP and invasive ICP measurement. Two independent reviewers screened abstracts, reviewed full-text articles, and extracted data. Correlation coefficients, sensitivity, specificity, and positive and negative likelihood ratios were calculated using DerSimonian and Laird methods and bivariate random effects models. The I(2) statistic was used as a measure of heterogeneity. Among 355 identified citations, 12 studies that enrolled 546 patients were included in the meta-analysis. The pooled correlation coefficient between IOP and ICP was 0.44 (95% CI 0.26-0.63, I(2) = 97.7%, p < 0.001). The summary sensitivity and specificity for IOP for diagnosing intracranial hypertension were 81% (95% CI 26%-98%, I(2) = 95.2%, p < 0.01) and 95% (95% CI 43%-100%, I(2) = 97.7%, p < 0.01), respectively. The summary positive and negative likelihood ratios were 14.8 (95% CI 0.5-417.7) and 0.2 (95% CI 0.02-1.7), respectively. When ICP and IOP measurements were taken within 1 hour of another, correlation between the measures improved. Although a modest aggregate correlation was found between IOP and ICP, the pooled diagnostic accuracy suggests that IOP measurement may be of clinical utility in the detection of intracranial hypertension. Given the significant heterogeneity between included studies, further investigation is required prior to the adoption of IOP in the evaluation of intracranial hypertension into routine practice.
Kumar, Praveen; Mardon, Marianne; Bradley, Michael; Gray, Selena; Swinkels, Annette
2014-11-01
Glenohumeral subluxation (GHS) is a common poststroke complication. Treatment of GHS is hampered by the lack of objective, real-time clinical measurements. The aims of this study were: (1) to compare an ultrasound method of GHS measurement with the fingerbreadth palpation method using a receiver operating characteristic curve (ROC) and (2) to report the sensitivity and specificity of this method. A prospective study was conducted. The study was conducted in local hospitals and day centers in the southwest of England. One hundred five patients who had one-sided weakness following a first-time stroke (51 men, 54 women; mean age=71 years, SD=11) and who gave informed consent were enrolled in the study. Ultrasound measurements of acromion-greater tuberosity (AGT) distance were used for the assessment of GHS. Measurements were undertaken on both shoulders by a research physical therapist trained in shoulder ultrasound with the patient seated in a standardized position. Fingerbreadth palpation assessment of GHS was undertaken by a clinical physical therapist based at the hospital, who also visited the day centers. The area under the ROC curve was 0.73 (95% confidence interval [95% CI]=0.63, 0.83), suggesting that the ultrasound method has good agreement compared with the fingerbreadth palpation method. A cutoff point of ≥0.2 cm AGT measurement difference between affected and unaffected shoulders generated a sensitivity of 68% (95% CI=51%, 75%), a specificity of 62% (95% CI=47%, 80%), a positive likelihood ratio of 1.79 (95% CI=1.1, 2.9), and a negative likelihood ratio of 0.55 (95% CI=0.4, 0.8). Clinical therapists involved in the routine care of patients conducted the fingerbreadth palpation method. It is likely that they were aware of the patients' subluxation status. The ultrasound method can detect minor asymmetry (≤0.5 cm) and has the potential advantage over the fingerbreadth palpation method of identifying patients with minor subluxation. © 2014 American Physical Therapy Association.
Ali, Innocent M; Bigoga, Jude D; Forsah, Dorothy A; Cho-Ngwa, Fidelis; Tchinda, Vivian; Moor, Vicky Ama; Fogako, Josephine; Nyongalema, Philomena; Nkoa, Theresa; Same-Ekobo, Albert; Mbede, Joseph; Fondjo, Etienne; Mbacham, Wilfred F; Leke, Rose G F
2016-01-20
All suspected cases of malaria should receive a diagnostic test prior to treatment with artemisinin-based combinations based on the new WHO malaria treatment guidelines. This study compared the accuracy and some operational characteristics of 22 different immunochromatographic antigen capture point-of- malaria tests (RDTs) in Cameroon to inform test procurement prior to deployment of artemisinin-based combinations for malaria treatment. One hundred human blood samples (50 positive and 50 negative) collected from consenting febrile patients in two health centres at Yaoundé were used for evaluation of the 22 RDTs categorized as "Pf Only" (9) or "Pf + PAN" (13) based on parasite antigen captured [histidine rich protein II (HRP2) or lactate dehydrogenase (pLDH) or aldolase]. RDTs were coded to blind technicians performing the tests. The sensitivity, specificity, and predictive values of the positive and negative tests (PPV and NPV) as well as the likelihood ratios were assessed. The reliability and some operational characteristics were determined as the mean values from two assessors, and the Cohen's kappa statistic was then used to compare agreement. Light microscopy was the referent. Of all RDTs tested, 94.2 % (21/22) had sensitivity values greater than 90% among which 14 (63.6%) were 'Pf + PAN' RDTs. The specificity was generally lower than the sensitivity for all RDTs and poorer for "Pf Only" RDTs. The predictive values and likelihood ratios were better for non-HRP2 analytes for "Pf + PAN" RDTs. The Kappa value for most of the tests obtained was around 67% (95% CI 50-69%), corresponding to a moderate agreement. Overall, 94.2% (21/22) of RDTs tested had accuracy within the range recommended by the WHO, while one performed poorly, below acceptable levels. Seven "Pf + PAN" and 3 "Pf Only" RDTs were selected for further assessment based on performance characteristics. Harmonizing RDT test presentation and procedures would prevent mistakes of test performance and interpretation.
Faes, L; Bodmer, N S; Bachmann, L M; Thiel, M A; Schmid, M K
2014-07-01
To clarify the screening potential of the Amsler grid and preferential hyperacuity perimetry (PHP) in detecting or ruling out wet age-related macular degeneration (AMD). Medline, Scopus and Web of Science (by citation of reference) were searched. Checking of reference lists of review articles and of included articles complemented electronic searches. Papers were selected, assessed, and extracted in duplicate. Systematic review and meta-analysis. Twelve included studies enrolled 903 patients and allowed constructing 27 two-by-two tables. Twelve tables reported on the Amsler grid and its modifications, twelve tables reported on the PHP, one table assessed the MCPT and two tables assessed the M-charts. All but two studies had a case-control design. The pooled sensitivity of studies assessing the Amsler grid was 0.78 (95% confidence intervals; 0.64-0.87), and the pooled specificity was 0.97 (95% confidence intervals; 0.91-0.99). The corresponding positive and negative likelihood ratios were 23.1 (95% confidence intervals; 8.4-64.0) and 0.23 (95% confidence intervals; 0.14-0.39), respectively. The pooled sensitivity of studies assessing the PHP was 0.85 (95% confidence intervals; 0.80-0.89), and specificity was 0.87 (95% confidence intervals; 0.82-0.91). The corresponding positive and negative likelihood ratios were 6.7 (95% confidence intervals; 4.6-9.8) and 0.17 (95% confidence intervals; 0.13-0.23). No pooling was possible for MCPT and M-charts. Results from small preliminary studies show promising test performance characteristics both for the Amsler grid and PHP to rule out wet AMD in the screening setting. To what extent these findings can be transferred to a real clinic practice still needs to be established.
Validation of the WristOx 3100 oximeter for the diagnosis of sleep apnea/hypopnea syndrome.
Nigro, Carlos Alberto; Aimaretti, Silvia; Gonzalez, Sergio; Rhodius, Edgardo
2009-05-01
To evaluate the diagnostic accuracy of the Nonin WristOx 3100 and its software (nVision 5.0) in patients with suspicion of sleep apnea/hypopnea syndrome (SAHS). All participants (168) had the oximetry and polysomnography simultaneously. The two recordings were interpreted blindly. The software calculated: adjusted O(2) desaturation index [ADI]-mean number of O(2) desaturation per hour of total recording analyzed time of > or = 2%, 3%, 4%, 5%, and 6% (ADI2, 3, 4, 5, and 6) and AT90-accumulated time at SO(2) < 90%. The ADI2, 3, 4, 5, and 6 and the AT90 cutoff points that better discriminated between subjects with or without SAHS arose from the receiver operating characteristic curve analysis. The sensitivity (S), specificity (E), and positive and negative likelihood ratio (LR+, LR-) for the different thresholds for ADI were calculated. One hundred and fifty-four patients were included (119 men, mean age 51, median apnea/hypopnea index [AHI] 14, median body mass index [BMI] 28.3 kg/m(2)). The best cutoff points of ADI were: SAHS = AHI > or = 5: ADI2 > 19.3 (S 89%, E 94%, LR+ 15.5 LR- 0.11); SAHS =AHI > or = 10: ADI3 > 10.5 (S 88%, E 94%, LR+ 15 LR- 0.12); SAHS = AHI > or = 15: ADI3 > 13.4 (S 88%, E 90%, LR+ 8.9, LR- 0.14). AT90 had the lowest diagnosis accuracy. An ADI2 < or = 12.2 excluded SAHS (AHI > or = 5 and 10; S 100%, LR- 0) and ADI3 > 4.3 (AHI > or = 5 and 10) or 32 (AHI > or = 15) confirmed SAHS (E 100%). A negative oximetry defined as ADI2 < or = 12.2 excluded SAHS defined as AHI > or = 5 or 10 with a sensitivity and negative likelihood ratio of 100% and 0%, respectively. Furthermore, a positive oximetry defined as an ADI3 > 32 (SAHS = AHI > or = 15) had a specificity of 100% to confirm the pathology.
Multiple Cognitive Control Effects of Error Likelihood and Conflict
Brown, Joshua W.
2010-01-01
Recent work on cognitive control has suggested a variety of performance monitoring functions of the anterior cingulate cortex, such as errors, conflict, error likelihood, and others. Given the variety of monitoring effects, a corresponding variety of control effects on behavior might be expected. This paper explores whether conflict and error likelihood produce distinct cognitive control effects on behavior, as measured by response time. A change signal task (Brown & Braver, 2005) was modified to include conditions of likely errors due to tardy as well as premature responses, in conditions with and without conflict. The results discriminate between competing hypotheses of independent vs. interacting conflict and error likelihood control effects. Specifically, the results suggest that the likelihood of premature vs. tardy response errors can lead to multiple distinct control effects, which are independent of cognitive control effects driven by response conflict. As a whole, the results point to the existence of multiple distinct cognitive control mechanisms and challenge existing models of cognitive control that incorporate only a single control signal. PMID:19030873
Heersink, Daniel K; Caley, Peter; Paini, Dean R; Barry, Simon C
2016-05-01
The cost of an uncontrolled incursion of invasive alien species (IAS) arising from undetected entry through ports can be substantial, and knowledge of port-specific risks is needed to help allocate limited surveillance resources. Quantifying the establishment likelihood of such an incursion requires quantifying the ability of a species to enter, establish, and spread. Estimation of the approach rate of IAS into ports provides a measure of likelihood of entry. Data on the approach rate of IAS are typically sparse, and the combinations of risk factors relating to country of origin and port of arrival diverse. This presents challenges to making formal statistical inference on establishment likelihood. Here we demonstrate how these challenges can be overcome with judicious use of mixed-effects models when estimating the incursion likelihood into Australia of the European (Apis mellifera) and Asian (A. cerana) honeybees, along with the invasive parasites of biosecurity concern they host (e.g., Varroa destructor). Our results demonstrate how skewed the establishment likelihood is, with one-tenth of the ports accounting for 80% or more of the likelihood for both species. These results have been utilized by biosecurity agencies in the allocation of resources to the surveillance of maritime ports. © 2015 Society for Risk Analysis.
Multibaseline gravitational wave radiometry
DOE Office of Scientific and Technical Information (OSTI.GOV)
Talukder, Dipongkar; Bose, Sukanta; Mitra, Sanjit
2011-03-15
We present a statistic for the detection of stochastic gravitational wave backgrounds (SGWBs) using radiometry with a network of multiple baselines. We also quantitatively compare the sensitivities of existing baselines and their network to SGWBs. We assess how the measurement accuracy of signal parameters, e.g., the sky position of a localized source, can improve when using a network of baselines, as compared to any of the single participating baselines. The search statistic itself is derived from the likelihood ratio of the cross correlation of the data across all possible baselines in a detector network and is optimal in Gaussian noise.more » Specifically, it is the likelihood ratio maximized over the strength of the SGWB and is called the maximized-likelihood ratio (MLR). One of the main advantages of using the MLR over past search strategies for inferring the presence or absence of a signal is that the former does not require the deconvolution of the cross correlation statistic. Therefore, it does not suffer from errors inherent to the deconvolution procedure and is especially useful for detecting weak sources. In the limit of a single baseline, it reduces to the detection statistic studied by Ballmer [Classical Quantum Gravity 23, S179 (2006).] and Mitra et al.[Phys. Rev. D 77, 042002 (2008).]. Unlike past studies, here the MLR statistic enables us to compare quantitatively the performances of a variety of baselines searching for a SGWB signal in (simulated) data. Although we use simulated noise and SGWB signals for making these comparisons, our method can be straightforwardly applied on real data.« less
Beliefs about Genetically Targeted Care in African Americans
Halbert, Chanita Hughes; McDonald, Jasmine A.; Magwood, Gayenell; Jefferson, Melanie
2018-01-01
We examined beliefs about genetically targeted care (GTC) among African American men and women in a hospital-based sample and identified sociodemographic, cultural, and clinical factors having significant independent associations with these beliefs. Specifically, beliefs about GTC were evaluated after respondents were randomly primed with a racial or non-racial cue about race and genetics. Despite priming with a racial or non-racial cue, many respondents had positive beliefs about GTC. But, 49% believed that GTC would limit access to medical treatment, 46% believed that people will not trust GTC, and 20% believed that people like them would not benefit from GTC. Racial and non-racial priming did not have significant associations with negative beliefs about GTC. However, cultural beliefs related to temporal orientation were associated significantly with believing that genetically targeted care will limit access to medical treatment. Greater levels of future temporal orientation were associated with a reduced likelihood of endorsing this belief (OR = 0.70, 95% CI = 0.49, 1.01, p = 0.05). Respondents who had a chronic medical condition had an almost three-fold greater likelihood of believing that they would not benefit from GTC (OR = 2.90, 95% CI = 1.00, 8.37, p = 0.05). Greater exposure to information about genetic testing for chronic conditions was also associated with a reduced likelihood of believing that they would not benefit from GTC (OR = 0.40, 95% CI = 0.64, 0.91, p = 0.02). African Americans have diverse beliefs about GTC that should be considered as genetic and genomic services are offered. PMID:28599763
Kohrt, Brandon A; Luitel, Nagendra P; Acharya, Prakash; Jordans, Mark J D
2016-03-08
Despite recognition of the burden of disease due to mood disorders in low- and middle-income countries, there is a lack of consensus on best practices for detecting depression. Self-report screening tools, such as the Patient Health Questionnaire (PHQ-9), require modification for low literacy populations and to assure cultural and clinical validity. An alternative approach is to employ idioms of distress that are locally salient, but these are not synonymous with psychiatric categories. Therefore, our objectives were to evaluate the validity of the PHQ-9, assess the added value of using idioms of distress, and develop an algorithm for depression detection in primary care. We conducted a transcultural translation of the PHQ-9 in Nepal using qualitative methods to achieve semantic, content, technical, and criterion equivalence. Researchers administered the Nepali PHQ-9 to randomly selected patients in a rural primary health care center. Trained psychosocial counselors administered a validated Nepali depression module of the Composite International Diagnostic Interview (CIDI) to validate the Nepali PHQ-9. Patients were also assessed for local idioms of distress including heart-mind problems (Nepali, manko samasya). Among 125 primary care patients, 17 (14 %) were positive for a major depressive episode in the prior 2 weeks based on CIDI administration. With a Nepali PHQ-9 cutoff ≥ 10: sensitivity = 0.94, specificity = 0.80, positive predictive value (PPV) =0.42, negative predictive value (NPV) =0.99, positive likelihood ratio = 4.62, and negative likelihood ratio = 0.07. For heart-mind problems: sensitivity = 0.94, specificity = 0.27, PPV = 0.17, NPV = 0.97. With an algorithm comprising two screening questions (1. presence of heart-mind problems and 2. function impairment due to heart-mind problems) to determine who should receive the full PHQ-9, the number of patients requiring administration of the PHQ-9 could be reduced by 50 %, PHQ-9 false positives would be reduced by 18 %, and 88 % of patients with depression would be correctly identified. Combining idioms of distress with a transculturally-translated depression screener increases efficiency and maintains accuracy for high levels of detection. The algorithm reduces the time needed for primary healthcare staff to verbally administer the tool for patients with limited literacy. The burden of false positives is comparable to rates in high-income countries and is a limitation for universal primary care screening.
Empirical likelihood inference in randomized clinical trials.
Zhang, Biao
2017-01-01
In individually randomized controlled trials, in addition to the primary outcome, information is often available on a number of covariates prior to randomization. This information is frequently utilized to undertake adjustment for baseline characteristics in order to increase precision of the estimation of average treatment effects; such adjustment is usually performed via covariate adjustment in outcome regression models. Although the use of covariate adjustment is widely seen as desirable for making treatment effect estimates more precise and the corresponding hypothesis tests more powerful, there are considerable concerns that objective inference in randomized clinical trials can potentially be compromised. In this paper, we study an empirical likelihood approach to covariate adjustment and propose two unbiased estimating functions that automatically decouple evaluation of average treatment effects from regression modeling of covariate-outcome relationships. The resulting empirical likelihood estimator of the average treatment effect is as efficient as the existing efficient adjusted estimators 1 when separate treatment-specific working regression models are correctly specified, yet are at least as efficient as the existing efficient adjusted estimators 1 for any given treatment-specific working regression models whether or not they coincide with the true treatment-specific covariate-outcome relationships. We present a simulation study to compare the finite sample performance of various methods along with some results on analysis of a data set from an HIV clinical trial. The simulation results indicate that the proposed empirical likelihood approach is more efficient and powerful than its competitors when the working covariate-outcome relationships by treatment status are misspecified.
Nazir, Mudasir; Wani, Wasim Ahmad; Malik, Muzaffar Ahmad; Mir, Mohd Rafiq; Ashraf, Younis; Kawoosa, Khalid; Ali, Syed Wajid
To assess the performance of cerebrospinal fluid (CSF) lactate as a biomarker to differentiate bacterial meningitis from viral meningitis in children, and to define an optimal CSF lactate concentration that can be called significant for the differentiation. Children with clinical findings compatible with meningitis were studied. CSF lactate and other conventional CSF parameters were recorded. At a cut-off value of 3mmol/L, CSF lactate had a sensitivity of 0.90, specificity of 1.0, positive predictive value of 1.0, and negative predictive value of 0.963, with an accuracy of 0.972. The positive and negative likelihood ratios were 23.6 and 0.1, respectively. When comparing between bacterial and viral meningitis, the area under the curve for CSF lactate was 0.979. The authors concluded that CSF lactate has high sensitivity and specificity in differentiating bacterial from viral meningitis. While at a cut-off value of 3mmol/L, CSF lactate has high diagnostic accuracy for bacterial meningitis, mean levels in viral meningitis remain essentially below 2mmol/L. Copyright © 2017 Sociedade Brasileira de Pediatria. Published by Elsevier Editora Ltda. All rights reserved.
Barbaro, Nicole; Parkhill, Michele R; Nguyen, David
2018-07-01
Attachment theory has increasingly been utilized to understand the etiology of sexual violence, and anxious attachment appears to be especially informative in this domain. We investigate the influence of general anxious attachment and specific anxious attachment on hostile masculine attitudes to predict male-perpetrated sexual assault. We hypothesize that hostile masculinity will mediate the relationship between general anxious attachment style and sexual assault perpetration (Hypothesis 1) and the relationship between specific anxious attachment to the assaulted woman and sexual assault perpetration (Hypothesis 2). Men ( N = 193) completed the Sexual Experiences Survey (SES) to determine sexual assault history and completed measures of general attachment style, specific attachment to the woman involved in the sexual activity, and measures of hostile masculine attitudes. Results support the hypothesized mediation models, such that general anxious attachment and specific anxious attachment are significantly associated with hostile masculinity, which in turn, predicts the likelihood of male-perpetrated sexual assault. The findings suggest that the unique characteristics of anxious attachment may escalate into hostile masculinity, which then increases the likelihood of sexual assault perpetration. This research is the first to investigate attachment bonds to the woman involved in the sexual activity and likelihood of sexual assault perpetration against the same woman.
Peterman, Jerusha Nelson; Silka, Linda; Bermudez, Odilia I; Wilde, Parke E; Rogers, Beatrice Lorge
2011-09-01
Refugees in the United States have higher rates of some chronic diseases than US-born residents or other first-generation immigrants. This may be partially a result of dietary practices in the United States. There is limited information about which factors are related to dietary practices in refugee populations, particularly those who have been in the United States for 10 to 20 years. Research with Cambodian communities may be useful for examining the relationship between refugee characteristics and dietary practices. Two focus groups (n=11) and a survey (n=150) of Cambodian refugee women were conducted in Lowell, MA, from 2007 to 2008. χ(2) analyses, t tests, and analysis of variance tests were used to describe differences in dietary practices (24-hour recall and a targeted qualitative food assessment) by group characteristics. Higher acculturation was related to higher likelihood of eating brown rice/whole grains, and to lower likelihood of eating high-sodium Asian sauces. Higher education was related to higher likelihood of eating vegetables and fruits and to eating white rice fewer times. Nutrition education and receiving dietary advice from a health care provider were related to higher likelihood of eating whole grains/brown rice. Having a child at home was related to a higher likelihood of eating fast food. Among Cambodian refugees who have been in the United States for 10 to 20 years, dietary practices appear to have a relationship with acculturation (positive association), the interrupted education common to refugees (negative association), nutrition education from either programs or health care providers (positive association), and having a child at home (negative association). Copyright © 2011 American Dietetic Association. Published by Elsevier Inc. All rights reserved.
Midttun, Linda
2007-03-01
In the aftermath of the Norwegian hospital reform of 2002, the private supply of specialized healthcare has increased substantially. This article analyses the likelihood of medical specialists working in the private sector. Sector choice is operationalized in two ways: first, as the likelihood of medical specialists working in the private sector at all (at least 1% of the total work hours), and second, as the likelihood of working full-time (90-100%) privately. The theoretical framework is embedded in work values theory and the results suggest that work values are important predictors of sector choice. All analyses are based on a postal questionnaire survey of medical specialists working in private contract practices and for-profit hospitals and a control group of specialists selected from the Norwegian Medical Association's member register. The analyses revealed that while autonomy values impact positively on the propensity for allocating any time at all to the private sector, professional values have a negative effect. Given that the medical specialist already works in the private sector, a high valuation of professional values and payment and benefit values increases the likelihood of having a dual sector job rather than a full-time private position. However, due to the cross-sectional structure of the data and limitations in the dataset, causality questions cannot be fully settled on the basis of the analyses. The relationship between work values and sector choice should, therefore, be regarded as associations rather than causality links. Finally, the likelihood of working in the private sector varies significantly at the municipality level, suggesting that medical specialist's location is important for sector choice.
Civic Returns to Higher Education: A Note on Heterogeneous Effects
Brand, Jennie E.
2011-01-01
American educational leaders and philosophers have long valued schooling for its role in preparing the nation’s youth to be civically engaged citizens. Numerous studies have found a positive relationship between education and subsequent civic participation. However, little is known about possible variation in effects by selection into higher education, a critical omission considering education’s expressed role as a key mechanism for integrating disadvantaged individuals into civic life. I disaggregate effects and examine whether civic returns to higher education are largest for disadvantaged low likelihood or advantaged high likelihood college goers. I find evidence for significant effect heterogeneity: civic returns to college are greatest among individuals who have a low likelihood for college completion. Returns decrease as the propensity for college increases. PMID:22223924
Maximum Likelihood Compton Polarimetry with the Compton Spectrometer and Imager
NASA Astrophysics Data System (ADS)
Lowell, A. W.; Boggs, S. E.; Chiu, C. L.; Kierans, C. A.; Sleator, C.; Tomsick, J. A.; Zoglauer, A. C.; Chang, H.-K.; Tseng, C.-H.; Yang, C.-Y.; Jean, P.; von Ballmoos, P.; Lin, C.-H.; Amman, M.
2017-10-01
Astrophysical polarization measurements in the soft gamma-ray band are becoming more feasible as detectors with high position and energy resolution are deployed. Previous work has shown that the minimum detectable polarization (MDP) of an ideal Compton polarimeter can be improved by ˜21% when an unbinned, maximum likelihood method (MLM) is used instead of the standard approach of fitting a sinusoid to a histogram of azimuthal scattering angles. Here we outline a procedure for implementing this maximum likelihood approach for real, nonideal polarimeters. As an example, we use the recent observation of GRB 160530A with the Compton Spectrometer and Imager. We find that the MDP for this observation is reduced by 20% when the MLM is used instead of the standard method.
Hui, David; Dos Santos, Renata; Chisholm, Gary; Bansal, Swati; Souza Crovador, Camila; Bruera, Eduardo
2015-03-15
Five highly specific physical signs associated with death within 3 days among cancer patients were recently reported that may aid in the diagnosis of impending death. In this study, the frequency and onset of another 52 bedside physical signs and their diagnostic performance for impending death were examined. Three hundred fifty-seven consecutive patients with advanced cancer who had been admitted to acute palliative care units at 2 tertiary care cancer centers were enrolled. Fifty-two physical signs were systematically documented every 12 hours from admission to death or discharge. The frequency and median time of onset of each sign from death backwards were examined, and the likelihood ratios (LRs) associated with death within 3 days were calculated. Two hundred three of the 357 patients (57%) died at the end of the admission. Eight physical signs that were highly diagnostic of impending death were identified. These signs occurred in 5% to 78% of the patients within the last 3 days of life, had a late onset, and had a high specificity (>95%) and a high positive LR for death within 3 days. They included nonreactive pupils (positive LR, 16.7; 95% confidence interval [CI], 14.9-18.6), a decreased response to verbal stimuli (positive LR, 8.3; 95% CI, 7.7-9), a decreased response to visual stimuli (positive LR, 6.7; 95% CI, 6.3-7.1), an inability to close eyelids (positive LR, 13.6; 95% CI, 11.7-15.5), drooping of the nasolabial fold (positive LR, 8.3; 95% CI, 7.7-8.9), hyperextension of the neck (positive LR, 7.3; 95% CI, 6.7-8), grunting of vocal cords (positive LR, 11.8; 95% CI, 10.3-13.4), and upper gastrointestinal bleeding (positive LR, 10.3; 95% CI, 9.5-11.1). Eight highly specific physical signs associated with death within 3 days among cancer patients were identified. These signs may inform the diagnosis of impending death. © 2015 American Cancer Society.
Scargill, J J; Reed, P; Kane, J
2013-01-01
Measurement of fractionated plasma or urine metadrenalines is the recommended screening test in the diagnosis of phaeochromocytoma, with clinical cut-offs geared towards diagnostic sensitivity. Current practice at Salford Royal Hospital is to add urine catecholamines onto samples with raised urine metadrenalines, with the aim of adding specificity to a diagnosis of phaeochromocytoma. This practice was reviewed by identifying a series of patients with raised urine metadrenalines who had catecholamines reflectively added. A total of 358 samples were identified from 242 patients, of which 228 had urine catecholamines measured. A diagnosis of 'phaeochromocytoma' (n = 41) or 'no phaeochromocytoma' (n = 90) was obtained in 131 of 228 patients, giving raised urine metadrenalines a positive predictive value for phaeochromocytoma of 31%. The finding of increased urine catecholamines in samples with raised urine metadrenalines increased specificity for phaeochromocytoma to 70%. However, 95% diagnostic specificity for phaeochromocytoma could be achieved by the introduction of a second cut-off for urine metadrenalines geared towards maximizing specificity. Consideration of the degree of increase in urine metadrenalines is a superior method of determining the likelihood of phaeochromocytoma than measurement of urine catecholamines.
Older Adolescents' Positive Attitudes toward Younger Adolescents as Sexual Partners
ERIC Educational Resources Information Center
Hegna, Kristinn; Mossige, Svein; Wichstrom, Lars
2004-01-01
The prevalence of older adolescents' positive attitudes toward younger sexual partners was investigated through three measures of self-reported hypothetical likelihood of having sex with preadolescents and younger adolescents (LSA), using a school-based cluster sample of 710 Norwegian 18- to 19-year-olds attending nonvocational high schools in…
Ecological consequences of colony structure in dynamic ant nest networks.
Ellis, Samuel; Franks, Daniel W; Robinson, Elva J H
2017-02-01
Access to resources depends on an individual's position within the environment. This is particularly important to animals that invest heavily in nest construction, such as social insects. Many ant species have a polydomous nesting strategy: a single colony inhabits several spatially separated nests, often exchanging resources between the nests. Different nests in a polydomous colony potentially have differential access to resources, but the ecological consequences of this are unclear. In this study, we investigate how nest survival and budding in polydomous wood ant ( Formica lugubris ) colonies are affected by being part of a multi-nest system. Using field data and novel analytical approaches combining survival models with dynamic network analysis, we show that the survival and budding of nests within a polydomous colony are affected by their position in the nest network structure. Specifically, we find that the flow of resources through a nest, which is based on its position within the wider nest network, determines a nest's likelihood of surviving and of founding new nests. Our results highlight how apparently disparate entities in a biological system can be integrated into a functional ecological unit. We also demonstrate how position within a dynamic network structure can have important ecological consequences.
Shrestha, Swastina; Dave, Amish J; Losina, Elena; Katz, Jeffrey N
2016-07-07
Administrative health care data are frequently used to study disease burden and treatment outcomes in many conditions including osteoarthritis (OA). OA is a chronic condition with significant disease burden affecting over 27 million adults in the US. There are few studies examining the performance of administrative data algorithms to diagnose OA. The purpose of this study is to perform a systematic review of administrative data algorithms for OA diagnosis; and, to evaluate the diagnostic characteristics of algorithms based on restrictiveness and reference standards. Two reviewers independently screened English-language articles published in Medline, Embase, PubMed, and Cochrane databases that used administrative data to identify OA cases. Each algorithm was classified as restrictive or less restrictive based on number and type of administrative codes required to satisfy the case definition. We recorded sensitivity and specificity of algorithms and calculated positive likelihood ratio (LR+) and positive predictive value (PPV) based on assumed OA prevalence of 0.1, 0.25, and 0.50. The search identified 7 studies that used 13 algorithms. Of these 13 algorithms, 5 were classified as restrictive and 8 as less restrictive. Restrictive algorithms had lower median sensitivity and higher median specificity compared to less restrictive algorithms when reference standards were self-report and American college of Rheumatology (ACR) criteria. The algorithms compared to reference standard of physician diagnosis had higher sensitivity and specificity than those compared to self-reported diagnosis or ACR criteria. Restrictive algorithms are more specific for OA diagnosis and can be used to identify cases when false positives have higher costs e.g. interventional studies. Less restrictive algorithms are more sensitive and suited for studies that attempt to identify all cases e.g. screening programs.
Parikh, Rajul S; Parikh, Shefali R; Kumar, Rajesh S; Prabakaran, S; Babu, J Gansesh; Thomas, Ravi
2008-07-01
To evaluate the diagnostic ability of scanning laser polarimetry (GDx variable corneal compensator [VCC]) for early glaucoma in Asian Indian eyes. Cross-sectional observational study. Two groups of patients (early glaucoma and normal) who satisfied the inclusion and exclusion criteria were included. Early glaucoma was diagnosed in presence of open angles, characteristic glaucomatous optic disc changes correlating with the visual field (VF) on automated perimetry (VF defect fulfilling at least 2 of 3 Anderson and Patella's criteria with mean deviation >or= -6 decibels). Normal subjects had visual acuity >or= 20/30 and intraocular pressure < 22 mmHg, with a normal optic disc and fields and no ocular abnormality. All patients underwent complete ophthalmic evaluation, including VF examination (24-2/30-2 Swedish interactive threshold algorithm standard program) and imaging with GDx VCC. Sensitivity, specificity, positive predictive value and negative predictive value, area under the receiving operating characteristic curve, and likelihood ratios (LRs) were calculated for various GDx VCC parameters. Seventy-four eyes (74 patients) with early glaucoma and 104 eyes (104 normal subjects) were enrolled. TSNIT Std Dev (temporal-superior-nasal-inferior-temporal standard deviation) had the best combination of sensitivity and specificity-61.3 and 95.2, respectively-followed by nerve fiber index score > 50 (sensitivity, 52.7%; specificity, 99%). Nerve fiber index score > 50 had positive and negative predictive values of 74.3% and 97.6%, respectively, for an assumed glaucoma prevalence of 5%. Nerve fiber index score > 50 had a positive LR (+LR) of 54.8 for early glaucoma. GDx VCC has moderate sensitivity, with high specificity, in the diagnosis of early glaucoma. The high +LR for the nerve fiber index score can provide valuable diagnostic information for individual patients.
Clark, S R; Baune, B T; Schubert, K O; Lavoie, S; Smesny, S; Rice, S M; Schäfer, M R; Benninger, F; Feucht, M; Klier, C M; McGorry, P D; Amminger, G P
2016-09-20
Current criteria identifying patients with ultra-high risk of psychosis (UHR) have low specificity, and less than one-third of UHR cases experience transition to psychosis within 3 years of initial assessment. We explored whether a Bayesian probabilistic multimodal model, combining baseline historical and clinical risk factors with biomarkers (oxidative stress, cell membrane fatty acids, resting quantitative electroencephalography (qEEG)), could improve this specificity. We analyzed data of a UHR cohort (n=40) with a 1-year transition rate of 28%. Positive and negative likelihood ratios were calculated for predictor variables with statistically significant receiver operating characteristic curves (ROCs), which excluded oxidative stress markers and qEEG parameters as significant predictors of transition. We clustered significant variables into historical (history of drug use), clinical (Positive and Negative Symptoms Scale positive, negative and general scores and Global Assessment of Function) and biomarker (total omega-3, nervonic acid) groups, and calculated the post-test probability of transition for each group and for group combinations using the odds ratio form of Bayes' rule. Combination of the three variable groups vastly improved the specificity of prediction (area under ROC=0.919, sensitivity=72.73%, specificity=96.43%). In this sample, our model identified over 70% of UHR patients who transitioned within 1 year, compared with 28% identified by standard UHR criteria. The model classified 77% of cases as very high or low risk (P>0.9, <0.1) based on history and clinical assessment, suggesting that a staged approach could be most efficient, reserving fatty-acid markers for 23% of cases remaining at intermediate probability following bedside interview.
Cumulative Incidence of False-Positive Results in Repeated, Multimodal Cancer Screening
Croswell, Jennifer Miller; Kramer, Barnett S.; Kreimer, Aimee R.; Prorok, Phil C.; Xu, Jian-Lun; Baker, Stuart G.; Fagerstrom, Richard; Riley, Thomas L.; Clapp, Jonathan D.; Berg, Christine D.; Gohagan, John K.; Andriole, Gerald L.; Chia, David; Church, Timothy R.; Crawford, E. David; Fouad, Mona N.; Gelmann, Edward P.; Lamerato, Lois; Reding, Douglas J.; Schoen, Robert E.
2009-01-01
PURPOSE Multiple cancer screening tests have been advocated for the general population; however, clinicians and patients are not always well-informed of screening burdens. We sought to determine the cumulative risk of a false-positive screening result and the resulting risk of a diagnostic procedure for an individual participating in a multimodal cancer screening program. METHODS Data were analyzed from the intervention arm of the ongoing Prostate, Lung, Colorectal, and Ovarian (PLCO) Cancer Screening Trial, a randomized controlled trial to determine the effects of prostate, lung, colorectal, and ovarian cancer screening on disease-specific mortality. The 68,436 participants, aged 55 to 74 years, were randomized to screening or usual care. Women received serial serum tests to detect cancer antigen 125 (CA-125), transvaginal sonograms, posteroanterior-view chest radiographs, and flexible sigmoidoscopies. Men received serial chest radiographs, flexible sigmoidoscopies, digital rectal examinations, and serum prostate-specific antigen tests. Fourteen screening examinations for each sex were possible during the 3-year screening period. RESULTS After 14 tests, the cumulative risk of having at least 1 false-positive screening test is 60.4% (95% CI, 59.8%–61.0%) for men, and 48.8% (95% CI, 48.1%–49.4%) for women. The cumulative risk after 14 tests of undergoing an invasive diagnostic procedure prompted by a false-positive test is 28.5% (CI, 27.8%–29.3%) for men and 22.1% (95% CI, 21.4%–22.7%) for women. CONCLUSIONS For an individual in a multimodal cancer screening trial, the risk of a false-positive finding is about 50% or greater by the 14th test. Physicians should educate patients about the likelihood of false positives and resulting diagnostic interventions when counseling about cancer screening. PMID:19433838
Boonyaviwat, Onsuree; Pacharn, Punchama; Jirapongsananuruk, Orathai; Vichyanond, Pakit; Visitsunthorn, Nualanong
2015-12-01
Double-blind, placebo-controlled food challenge is the gold standard for diagnosing food allergy. However, it is a time-consuming procedure and requires onsite medical supervision and resuscitating medicines and devices on hand. The objective of this study was to compare the atopy patch test (APT) with the oral food challenge test (OFC) in children with suspected food allergy-related gastrointestinal (GI) symptoms. A prospective self-controlled study enrolled children with a history of suspected food allergy-related GI symptoms. Skin prick test (SPT) and APT using lyophilized and commercial allergen extracts for cow's milk, egg, wheat, soy, and shrimp were evaluated, and OFC was performed. Thirty-nine patients (25 boys, median age 2.4 yrs) with 76 events of suspected food allergy-related GI symptoms were enrolled. SPT was positive in 11/76 events (14.5%). Sensitivity, specificity, predictive values, and likelihood ratio were calculated related to the food challenge outcome. Of 41 OFC, 30 (73.2%) were positive. APT using lyophilized allergen extracts yielded high sensitivity (80%) and high positive predictive value (85.7%). APT using commercial allergen extracts yielded low sensitivity (30%) but high specificity (90%). The negative predictive value of APT using lyophilized and commercial allergen extracts was 53.8% and 32.2%, respectively. All cases with positive APT using lyophilized allergen extracts together with positive SPT also had positive OFC. In contrast to commercial extracts, APT with lyophilized allergen extracts is reliable, safe, and maybe useful for the diagnosis of suspected food allergy-related GI symptoms in children. OFC is still needed in most of the cases. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Missed Lesions at CT Colonography: Lessons Learned
Pickhardt, Perry J.
2017-01-01
Misinterpretation at CT colonography (CTC) can result in either a colorectal lesion being missed (false negative) or a false-positive diagnosis. This review will largely focus on potential missed lesions – and ways to avoid such misses. The general causes of false-negative interpretation at CTC can be broadly characterized and grouped into discrete categories related to suboptimal study technique, specific lesion characteristics, anatomic location, and imaging artifacts. Overlapping causes further increase the likelihood of missing a clinically relevant lesion. In the end, if the technical factors of bowel preparation, colonic distention, and robust CTC software are adequately addressed on a consistent basis, and the reader is aware of all the potential pitfalls at CTC, important lesions will seldom be missed. PMID:22539045
Screening tests: a review with examples
Niebo, Ron; Utell, Mark J.
2014-01-01
Screening tests are widely used in medicine to assess the likelihood that members of a defined population have a particular disease. This article presents an overview of such tests including the definitions of key technical (sensitivity and specificity) and population characteristics necessary to assess the benefits and limitations of such tests. Several examples are used to illustrate calculations, including the characteristics of low dose computed tomography as a lung cancer screen, choice of an optimal PSA cutoff and selection of the population to undergo mammography. The importance of careful consideration of the consequences of both false positives and negatives is highlighted. Receiver operating characteristic curves are explained as is the need to carefully select the population group to be tested. PMID:25264934
Yang, Ji; Gu, Hongya; Yang, Ziheng
2004-01-01
Chalcone synthase (CHS) is a key enzyme in the biosynthesis of flavonoides, which are important for the pigmentation of flowers and act as attractants to pollinators. Genes encoding CHS constitute a multigene family in which the copy number varies among plant species and functional divergence appears to have occurred repeatedly. In morning glories (Ipomoea), five functional CHS genes (A-E) have been described. Phylogenetic analysis of the Ipomoea CHS gene family revealed that CHS A, B, and C experienced accelerated rates of amino acid substitution relative to CHS D and E. To examine whether the CHS genes of the morning glories underwent adaptive evolution, maximum-likelihood models of codon substitution were used to analyze the functional sequences in the Ipomoea CHS gene family. These models used the nonsynonymous/synonymous rate ratio (omega = d(N)/ d(S)) as an indicator of selective pressure and allowed the ratio to vary among lineages or sites. Likelihood ratio test suggested significant variation in selection pressure among amino acid sites, with a small proportion of them detected to be under positive selection along the branches ancestral to CHS A, B, and C. Positive Darwinian selection appears to have promoted the divergence of subfamily ABC and subfamily DE and is at least partially responsible for a rate increase following gene duplication.
Plasma neutrophil gelatinase-associated lipocalin: a marker of acute pyelonephritis in children.
Kim, Byung Kwan; Yim, Hyung Eun; Yoo, Kee Hwan
2017-03-01
This study was designed to compare the diagnostic accuracy of plasma neutrophil gelatinase-associated lipocalin (NGAL) with procalcitonin (PCT), C-reactive protein (CRP), and white blood cells (WBCs) for predicting acute pyelonephritis (APN) in children with febrile urinary tract infections (UTIs). In total, 138 children with febrile UTIs (APN 59, lower UTI 79) were reviewed retrospectively. Levels of NGAL, PCT, CRP, and WBCs in blood were measured on admission. The diagnostic accuracy of the biomarkers was investigated. Independent predictors of APN were identified by multivariate logistic regression analysis. Receiver operating curve (ROC) analyses showed good diagnostic profiles of NGAL, PCT, CRP, and WBCs for identifying APN [area under the curve (AUC) 0.893, 0.855, 0.879, and 0.654, respectively]. However, multivariate analysis revealed only plasma NGAL level was an independent predictor of APN (P = 0.006). At the best cutoff values of all examined biomarkers for identifying APN, sensitivity (86 %), specificity (85 %), positive predictive value (81 %), and negative predictive value (89 %) of plasma NGAL levels were the highest. The optimal NGAL cutoff value was 117 ng/ml. The positive likelihood ratio [odds ratio (OR) 5.69, 95 % confidence interval (CI) 3.56-8.78], and negative likelihood ratio (OR 0.16, 95 % CI 0.08-0.29) of plasma NGAL for APN diagnosis also showed it seemed to be more accurate than serum PCT, CRP, and WBCs. Plasma NGAL can be more useful than serum PCT, CRP, and WBC levels for identifying APN in children with febrile UTIs.
Favaloro, Emmanuel J; McCaughan, Georgia; Mohammed, Soma; Lau, Kun Kan Edwin; Gemmell, Rosalie; Cavanaugh, Lauren; Donikian, Dea; Kondo, Mayuko; Brighton, Timothy; Pasalic, Leonardo
2018-04-17
Heparin induced thrombocytopenia (HIT) is a rare but potentially fatal complication of heparin therapy, which in a proportion of patients causes platelet activation and thrombosis. Initial clinical assessment of the likelihood of HIT is facilitated by laboratory testing to confirm or exclude HIT. This prospective investigation was performed over an 18-month period, and has involved testing of over 300 test samples from over 100 consecutive patients. Clinical assessment by 4T score was supplemented by laboratory tests that comprised both immunological [lateral flow ('STiC'), chemiluminescence (AcuStar; HIT-IgG (PF4-H) ), ELISA (Asserachrom HPIA IgG)] and functional assays [SRA, platelet aggregation using whole blood ('Multiplate') and platelet rich plasma ('LTA')]. We observed both false positive and false negative test findings with most assays. Overall, the whole blood aggregation method provided a reasonable alternative to SRA for identifying functional HIT. STiC, AcuStar and ELISA procedures were fairly comparable in terms of screening for HIT, although STiC and AcuStar both yielded false negatives, albeit also resulting in fewer false positives than ELISA. The 4T score had less utility in our patient cohort than we were expecting, although there was an association with the likelihood of HIT. Nevertheless, we accept that our observations are based on limited test numbers. In conclusion, no single approach (clinical or laboratory) was associated with optimal sensitivity or specificity of HIT exclusion or identification, and thus, a combination of clinical evaluation and laboratory testing will best ensure the accuracy of diagnosis. Crown Copyright © 2018. Published by Elsevier B.V. All rights reserved.
Maffei, E; Martini, C; Rossi, A; Mollet, N; Lario, C; Castiglione Morelli, M; Clemente, A; Gentile, G; Arcadi, T; Seitun, S; Catalano, O; Aldrovandi, A; Cademartiri, F
2012-08-01
The authors evaluated the diagnostic accuracy of second-generation dual-source (DSCT) computed tomography coronary angiography (CTCA) with iterative reconstructions for detecting obstructive coronary artery disease (CAD). Between June 2010 and February 2011, we enrolled 160 patients (85 men; mean age 61.2±11.6 years) with suspected CAD. All patients underwent CTCA and conventional coronary angiography (CCA). For the CTCA scan (Definition Flash, Siemens), we use prospective tube current modulation and 70-100 ml of iodinated contrast material (Iomeprol 400 mgI/ ml, Bracco). Data sets were reconstructed with iterative reconstruction algorithm (IRIS, Siemens). CTCA and CCA reports were used to evaluate accuracy using the threshold for significant stenosis at ≥50% and ≥70%, respectively. No patient was excluded from the analysis. Heart rate was 64.3±11.9 bpm and radiation dose was 7.2±2.1 mSv. Disease prevalence was 30% (48/160). Sensitivity, specificity and positive and negative predictive values of CTCA in detecting significant stenosis were 90.1%, 93.3%, 53.2% and 99.1% (per segment), 97.5%, 91.2%, 61.4% and 99.6% (per vessel) and 100%, 83%, 71.6% and 100% (per patient), respectively. Positive and negative likelihood ratios at the per-patient level were 5.89 and 0.0, respectively. CTCA with second-generation DSCT in the real clinical world shows a diagnostic performance comparable with previously reported validation studies. The excellent negative predictive value and likelihood ratio make CTCA a first-line noninvasive method for diagnosing obstructive CAD.
Renner, Swen C; Lüdtke, Bruntje; Kaiser, Sonja; Kienle, Julia; Schaefer, H Martin; Segelbacher, Gernot; Tschapka, Marco; Santiago-Alarcon, Diego
2016-08-01
Habitat characteristics determine the presence of individuals through resource availability, but at the same time, such features also influence the occurrence of parasites. We analyzed how birds respond to changes in interior forest structures, to forest management regimes, and to the risk of haemosporidian infections. We captured and took blood samples from blackcaps (Sylvia atricapilla) and chaffinches (Fringilla coelebs) in three different forest types (beech, mixed deciduous, spruce). We measured birds' body asymmetries, detected avian haemosporidians, and counted white blood cells as an immune measure of each individual per forest type. We used, to our knowledge for the first time, continuous forest structural parameters to quantify habitat structure, and found significant effects of habitat structure on parasite prevalence that previously have been undetected. We found three times higher prevalence for blackcaps compared with chaffinches. Parasite intensity varied significantly within host species depending on forest type, being lowest in beech forests for both host species. Structurally complex habitats with a high degree of entropy had a positive effect on the likelihood of acquiring an infection, but the effect on prevalence was negative for forest sections with a south facing aspect. For blackcaps, forest gaps also had a positive effect on prevalence, but canopy height had a negative one. Our results suggest that forest types and variations in forest structure influence the likelihood of acquiring an infection, which subsequently has an influence on host health status and body condition; however, responses to some environmental factors are host-specific. Copyright © 2016 Australian Society for Parasitology. Published by Elsevier Ltd. All rights reserved.
[Total serum calcium and corrected calcium as severity predictors in acute pancreatitis].
Gutiérrez-Jiménez, A A; Castro-Jiménez, E; Lagunes-Córdoba, R
2014-01-01
To evaluate total serum calcium (TC) and albumin-corrected calcium (ACC) as prognostic severity factors in acute pancreatitis (AP). Ninety-six patients were included in the study. They were diagnosed with AP and admitted to the Hospital Regional de Veracruz within the time frame of January 2010 to December 2012. AP severity was determined through the updated Atlanta Classification (2013). TC and ACC values were measured in the first 24hours of admittance and the percentages of sensitivity (S), specificity (Sp), positive predictive value (PPV), negative predictive value (NPV), positive likelihood ratio (LR+), and negative likelihood ratio (LR-) were calculated through ROC curves and contingency tables. In accordance with the updated Atlanta Classification, 70 patients presented with mild AP, 17 with moderately severe AP, and 9 with severe AP. Of the patient total, 61.5% were women, and 69.8% presented with biliary etiology. The maximum TC cut-off point was 7.5mg/dL, with values of S, 67%; Sp, 82%; PPV, 27%, and NPV, 96%. The maximum ACC cut-off point was 7.5mg/dL, with values of S, 67%; Sp, 90%; PPV, 40%; NPV, 96%. Both had values similar to those of the Ranson and APACHE II prognostic scales. TC and ACC, measured within the first 24hours, are useful severity predictors in acute pancreatitis, with sensitivity and predictive values comparable or superior to those of the conventional prognostic scales. Copyright © 2013 Asociación Mexicana de Gastroenterología. Published by Masson Doyma México S.A. All rights reserved.
Neyens, David M; Childers, Ashley Kay
2017-07-01
To determine the barriers and facilitators associated with willingness to use personal health information management (PHIM) systems to support an existing worksite wellness program (WWP). The study design involved a Web-based survey. The study setting was a regional hospital. Hospital employees comprised the study subjects. Willingness, barriers, and facilitators associated with PHIM were measured. Bivariate logit models were used to model two binary dependent variables. One model predicted the likelihood of believing PHIM systems would positively affect overall health and willingness to use. Another predicted the likelihood of worrying about online security and not believing PHIM systems would benefit health goals. Based on 333 responses, believing PHIM systems would positively affect health was highly associated with willingness to use PHIM systems (p < .01). Those comfortable online were 7.22 times more willing to use PHIM systems. Participants in exercise-based components of WWPs were 3.03 times more likely to be willing to use PHIM systems. Those who worried about online security were 5.03 times more likely to believe PHIM systems would not help obtain health goals. Comfort with personal health information online and exercise-based WWP experience was associated with willingness to use PHIM systems. However, nutrition-based WWPs did not have similar effects. Implementation barriers relate to technology anxiety and trust in security, as well as experience with specific WWP activities. Identifying differences between WWP components and addressing technology concerns before implementation of PHIM systems into WWPs may facilitate improved adoption and usage.
Code of Federal Regulations, 2014 CFR
2014-07-01
... and a likelihood of vacancies (e.g., science and engineering positions). (11) Develop procedures for... computer support of employees with disabilities consistent with DoD participation in activities of the...
Code of Federal Regulations, 2011 CFR
2011-07-01
... and a likelihood of vacancies (e.g., science and engineering positions). (11) Develop procedures for... computer support of employees with disabilities consistent with DoD participation in activities of the...
Code of Federal Regulations, 2013 CFR
2013-07-01
... and a likelihood of vacancies (e.g., science and engineering positions). (11) Develop procedures for... computer support of employees with disabilities consistent with DoD participation in activities of the...
Code of Federal Regulations, 2012 CFR
2012-07-01
... and a likelihood of vacancies (e.g., science and engineering positions). (11) Develop procedures for... computer support of employees with disabilities consistent with DoD participation in activities of the...
Hybrid pairwise likelihood analysis of animal behavior experiments.
Cattelan, Manuela; Varin, Cristiano
2013-12-01
The study of the determinants of fights between animals is an important issue in understanding animal behavior. For this purpose, tournament experiments among a set of animals are often used by zoologists. The results of these tournament experiments are naturally analyzed by paired comparison models. Proper statistical analysis of these models is complicated by the presence of dependence between the outcomes of fights because the same animal is involved in different contests. This paper discusses two different model specifications to account for between-fights dependence. Models are fitted through the hybrid pairwise likelihood method that iterates between optimal estimating equations for the regression parameters and pairwise likelihood inference for the association parameters. This approach requires the specification of means and covariances only. For this reason, the method can be applied also when the computation of the joint distribution is difficult or inconvenient. The proposed methodology is investigated by simulation studies and applied to real data about adult male Cape Dwarf Chameleons. © 2013, The International Biometric Society.
The Relationship Between Emotional Support and Health-Related Self-Efficacy in Older Prisoners.
Noujaim, Deborah; Fortinsky, Richard H; Barry, Lisa C
2017-09-01
To determine whether emotional support, and proportion of emotional support provided by specific sources (e.g., family, other prisoners, clinicians), is associated with health-related self-efficacy among older prisoners. Cross-sectional study of 140 older prisoners age ≥50 with chronic medical illness who completed face-to-face interviews. Logistic regression, controlling for demographic, incarceration, and clinical/behavioral factors evaluated the association between emotional support, operationalized as a score and as a proportion of total emotional support from specific sources, and health-related self-efficacy. Higher emotional support scores, and greater proportion of support from clinicians, were associated with lower likelihood of poor health-related self-efficacy. Those with >50% of their emotional support coming from other prisoners had higher likelihood of poor self-efficacy. Among older prisoners with chronic illness, higher emotional support, particularly from clinicians, is associated with lower likelihood of poor self-efficacy; relying on other prisoners for emotional support is associated with poor health-related self-efficacy.
Trzepacz, Paula T; Meagher, David J; Franco, José G
2016-05-01
Diagnostic classification systems do not incorporate phenomenological research findings about the three core symptom domains of delirium (Attentional/Cognitive, Circadian, Higher Level Thinking). We evaluated classification performances of novel Trzepacz, Meagher, and Franco research diagnostic criteria (TMF) that incorporate those domains and ICD-10, DSM-III-R, DSM-IV, and DSM-5. Primary data analysis of 641 patients with mixed neuropsychiatric profiles. Delirium (n=429) and nondelirium (n=212) reference standard groups were identified using cluster analysis of symptoms assessed using the Delirium Rating Scale-Revised-98. Accuracy, sensitivity, specificity, positive and negative predictive values (PPV, NPV), and likelihood ratios (LR+, LR-) are reported. TMF criteria had high sensitivity and specificity (87.4% and 89.2%), more balanced than DSM-III-R (100% and 31.6%), DSM-IV (97.7% and 74.1%), DSM-5 (97.7% and 72.6%), and ICD-10 (66.2% and 100%). PPV of DSM-III-R, DSM-IV, and DSM-5 were <90.0%, while PPV for ICD-10 and TMF were >90%. ICD-10 had the lowest NPV (59.4%). TMF had the highest LR+ (8.06) and DSM-III-R the lowest LR- (0.0). Overall, values for DSM-IV and DSM-5 were similar, whereas for ICD-10 and DSM-III-R were inverse of each other. In the pre-existing cognitive impairment/dementia subsample (n=128), TMF retained its highest LR+ though specificity (58.3%) became less well balanced with sensitivity (87.9%), which still exceeded that of DSM. TMF research diagnostic criteria performed well, with more balanced sensitivity and specificity and the highest likelihood ratio for delirium identification. Reflecting the three core domains of delirium, TMF criteria may have advantages in biological research where delineation of this syndrome is important. Copyright © 2016. Published by Elsevier Inc.
Yamamoto, Yosuke; Terada, Kazuhiko; Ohta, Mitsuyasu; Mikami, Wakako; Yokota, Hajime; Hayashi, Michio; Miyashita, Jun; Azuma, Teruhisa; Fukuma, Shingo; Fukuhara, Shunichi
2017-01-01
Objective Diagnosis of community-acquired pneumonia (CAP) in the elderly is often delayed because of atypical presentation and non-specific symptoms, such as appetite loss, falls and disturbance in consciousness. The aim of this study was to investigate the external validity of existing prediction models and the added value of the non-specific symptoms for the diagnosis of CAP in elderly patients. Design Prospective cohort study. Setting General medicine departments of three teaching hospitals in Japan. Participants A total of 109 elderly patients who consulted for upper respiratory symptoms between 1 October 2014 and 30 September 2016. Main outcome measures The reference standard for CAP was chest radiograph evaluated by two certified radiologists. The existing models were externally validated for diagnostic performance by calibration plot and discrimination. To evaluate the additional value of the non-specific symptoms to the existing prediction models, we developed an extended logistic regression model. Calibration, discrimination, category-free net reclassification improvement (NRI) and decision curve analysis (DCA) were investigated in the extended model. Results Among the existing models, the model by van Vugt demonstrated the best performance, with an area under the curve of 0.75(95% CI 0.63 to 0.88); calibration plot showed good fit despite a significant Hosmer-Lemeshow test (p=0.017). Among the non-specific symptoms, appetite loss had positive likelihood ratio of 3.2 (2.0–5.3), negative likelihood ratio of 0.4 (0.2–0.7) and OR of 7.7 (3.0–19.7). Addition of appetite loss to the model by van Vugt led to improved calibration at p=0.48, NRI of 0.53 (p=0.019) and higher net benefit by DCA. Conclusions Information on appetite loss improved the performance of an existing model for the diagnosis of CAP in the elderly. PMID:29122806
Fleming, Susannah; Gill, Peter; Jones, Caroline; Taylor, James A.; Van den Bruel, Ann; Heneghan, Carl; Roberts, Nia; Thompson, Matthew
2015-01-01
Importance Capillary refill time (CRT) is widely recommended as part of the routine assessment of unwell children. Objective To determine the diagnostic value of capillary refill time for a range of serious outcomes in children. Methods We searched Medline, Embase and CINAHL from inception to June 2014. We included studies that measured both capillary refill time and a relevant clinical outcome such as mortality, dehydration, meningitis, or other serious illnesses in children aged up to 18 years of age. We screened 1,265 references, of which 24 papers were included in this review. Where sufficient studies were available, we conducted meta-analysis and constructed hierarchical summary ROC curves. Results Meta-analysis on the relationship between capillary refill time and mortality resulted in sensitivity of 34.6% (95% CI 23.9 to 47.1%), specificity 92.3% (88.6 to 94.8%), positive likelihood ratio 4.49 (3.06 to 6.57), and negative likelihood ratio 0.71 (0.60 to 0.84). Studies of children attending Emergency Departments with vomiting and diarrhea showed that capillary refill time had specificity of 89 to 94% for identifying 5% dehydration, but sensitivity ranged from 0 to 94%. This level of heterogeneity precluded formal meta-analysis of this outcome. Meta-analysis was not possible for other outcomes due to insufficient data, but we found consistently high specificity for a range of outcomes including meningitis, sepsis, admission to hospital, hypoxia, severity of illness and dengue. Conclusions Our results show that capillary refill time is a specific sign, indicating that it can be used as a “red-flag”: children with prolonged capillary refill time have a four-fold risk of dying compared to children with normal capillary refill time. The low sensitivity means that a normal capillary refill time should not reassure clinicians. PMID:26375953
Tribble, David R.; Baqar, Shahida; Pang, Lorrin W.; Mason, Carl; Houng, Huo-Shu H.; Pitarangsi, Chittima; Lebron, Carlos; Armstrong, Adam; Sethabutr, Orntipa; Sanders, John W.
2008-01-01
High rates of Campylobacter fluoroquinolone resistance highlight the need to evaluate diagnostic strategies that can be used to assist with clinical management. Diagnostic tests were evaluated with U.S. soldiers presenting with acute diarrhea during deployment in Thailand. The results of bedside and field laboratory diagnostic tests were compared to stool microbiology findings for 182 enrolled patients. Campylobacter jejuni was isolated from 62% of the cases. Clinical and laboratory findings at the time of presentation were evaluated to determine their impact on the posttest probability, defined as the likelihood of a diagnosis of Campylobacter infection. Clinical findings, the results of tests for inflammation (stool occult blood testing [Hemoccult], fecal leukocytes, fecal lactoferrin, plasma C-reactive protein), and the numbers of Campylobacter-specific antibody-secreting cells in peripheral blood failed to increase the posttest probability above 90% in this setting of Campylobacter hyperendemicity when these findings were present. Positive results by a Campylobacter-specific commercial enzyme immunoassay (EIA) and, less so, a research PCR were strong positive predictors. The negative predictive value for ruling out Campylobacter infection, defined as a posttest probability of less than 10%, was similarly observed with these Campylobacter-specific stool-based tests as well the fecal leukocyte test. Compared to the other tests evaluated, the Campylobacter EIA is a sensitive and specific rapid diagnostic test that may assist with diagnostic evaluation, with consideration of the epidemiological setting, logistics, and cost. PMID:18234869
Crisi, Girolamo; Filice, Silvano; Michiara, Maria; Crafa, Pellegrino; Lana, Silvia
The objective of this study was to assess the effective performance of short echo time magnetic resonance spectroscopy (short TE MRS) for 2HG detection as biomarker of isocitrate dehydrogenase (IDH) status in all grade glioma (GL). A total of 82 GL patients were prospectively investigated by short TE MRS at 3.0 T as part of a multimodal magnetic resonance imaging study protocol. Spectral analysis was performed using linear combination model. Tumor specimens were diagnosed as IDH mutant or wild type according to the 2016 World Health Organization (WHO) classification of brain tumors. Spectra were analyzed for the presence of 2HG. The performance of short TE MRS was evaluated in terms of sensitivity, specificity, and positive and negative likelihood ratio on the overall sample and on GL WHO grades II and III and glioblastoma separately. The specificity and sensitivity estimated on the overall sample were 88% and 77%, respectively. In GL WHO grades II and III, 100% specificity and 75% sensitivity were estimated. We reiterate the feasibility to identify IDH status of brain GL using short TE MRS at 3.0 T. The method can correctly detect 2HG as expression of IDH mutation in WHO grades II and III GL with a 100% specificity but a 75% sensitivity. In the evaluation of glioblastoma, short TE MRS performs poorly having a 17% false positive rate.
Detection of Pathways Affected by Positive Selection in Primate Lineages Ancestral to Humans
Moretti, S.; Davydov, I.I.; Excoffier, L.
2017-01-01
Abstract Gene set enrichment approaches have been increasingly successful in finding signals of recent polygenic selection in the human genome. In this study, we aim at detecting biological pathways affected by positive selection in more ancient human evolutionary history. Focusing on four branches of the primate tree that lead to modern humans, we tested all available protein coding gene trees of the Primates clade for signals of adaptation in these branches, using the likelihood-based branch site test of positive selection. The results of these locus-specific tests were then used as input for a gene set enrichment test, where whole pathways are globally scored for a signal of positive selection, instead of focusing only on outlier “significant” genes. We identified signals of positive selection in several pathways that are mainly involved in immune response, sensory perception, metabolism, and energy production. These pathway-level results are highly significant, even though there is no functional enrichment when only focusing on top scoring genes. Interestingly, several gene sets are found significant at multiple levels in the phylogeny, but different genes are responsible for the selection signal in the different branches. This suggests that the same function has been optimized in different ways at different times in primate evolution. PMID:28333345
Sex differences in brain activation to emotional stimuli: a meta-analysis of neuroimaging studies.
Stevens, Jennifer S; Hamann, Stephan
2012-06-01
Substantial sex differences in emotional responses and perception have been reported in previous psychological and psychophysiological studies. For example, women have been found to respond more strongly to negative emotional stimuli, a sex difference that has been linked to an increased risk of depression and anxiety disorders. The extent to which such sex differences are reflected in corresponding differences in regional brain activation remains a largely unresolved issue, however, in part because relatively few neuroimaging studies have addressed this issue. Here, by conducting a quantitative meta-analysis of neuroimaging studies, we were able to substantially increase statistical power to detect sex differences relative to prior studies, by combining emotion studies which explicitly examined sex differences with the much larger number of studies that examined only women or men. We used an activation likelihood estimation approach to characterize sex differences in the likelihood of regional brain activation elicited by emotional stimuli relative to non-emotional stimuli. We examined sex differences separately for negative and positive emotions, in addition to examining all emotions combined. Sex differences varied markedly between negative and positive emotion studies. The majority of sex differences favoring women were observed for negative emotion, whereas the majority of the sex differences favoring men were observed for positive emotion. This valence-specificity was particularly evident for the amygdala. For negative emotion, women exhibited greater activation than men in the left amygdala, as well as in other regions including the left thalamus, hypothalamus, mammillary bodies, left caudate, and medial prefrontal cortex. In contrast, for positive emotion, men exhibited greater activation than women in the left amygdala, as well as greater activation in other regions including the bilateral inferior frontal gyrus and right fusiform gyrus. These meta-analysis findings indicate that the amygdala, a key region for emotion processing, exhibits valence-dependent sex differences in activation to emotional stimuli. The greater left amygdala response to negative emotion for women accords with previous reports that women respond more strongly to negative emotional stimuli, as well as with hypothesized links between increased neurobiological reactivity to negative emotion and increased prevalence of depression and anxiety disorders in women. The finding of greater left amygdala activation for positive emotional stimuli in men suggests that greater amygdala responses reported previously for men for specific types of positive stimuli may also extend to positive stimuli more generally. In summary, this study extends efforts to characterize sex differences in brain activation during emotion processing by providing the largest and most comprehensive quantitative meta-analysis to date, and for the first time examining sex differences as a function of positive vs. negative emotional valence. The current findings highlight the importance of considering sex as a potential factor modulating emotional processing and its underlying neural mechanisms, and more broadly, the need to consider individual differences in understanding the neurobiology of emotion. Copyright © 2012 Elsevier Ltd. All rights reserved.
Kandil, Emad; Tufaro, Anthony P; Carson, Kathryn A; Lin, Frank; Somervell, Helina; Farrag, Tarik; Dackiw, Alan; Zeiger, Martha; Tufano, Ralph P
2008-10-01
To determine the relationship between preoperative plasma 25-hydroxyvitamin D (25[OH]D) levels and severity of primary hyperparathyroidism (PHPT) and to explore whether presurgical 25(OH)D levels could predict the likelihood of positive results on technetium Tc 99m sestamibi scintigraphy. Retrospective analysis. Tertiary university referral center. A total of 421 consecutive patients underwent preoperative sestamibi scintigraphy and parathyroid exploration. Patients with cholecalciferol (vitamin D) deficiency, defined as plasma levels lower than 25 ng/mL, were compared with patients having no vitamin D deficiency. We explored the relationship between 25 (OH)D levels and intact parathyroid hormone (iPTH) levels, alkaline phosphatase (ALKP) levels, adenoma weight, binary sestamibi scan results, and postoperative serum calcium levels (at 1 week and 6 months). We hypothesized that severity of hypovitaminosis D would correlate with severity of PHPT and predict the likelihood of a positive finding on sestamibi scan. Concentrations of iPTH and ALKP and parathyroid adenoma weight were significantly higher in patients with lower 25(OH)D levels (P < .01 for all). Patients with hypovitaminosis D had a greater percentage decrease in serum calcium levels 1 week and 6 months postoperatively (P < .05). Median 25(OH)D levels were lower in patients with positive sestamibi scan results (P < .001). Patients with hypovitaminosis D present with more advanced indices of PHPT. Parathyroid sestamibi scanning is more likely to show positive results for this subset of patients who may then benefit from sestamibi scan-directed surgical intervention.
Duanngai, Krit; Sirasaporn, Patpiya; Ngaosinchai, Siriwan Surapaitoon
2017-01-01
The aim of this is to evaluate the reliability of the urine dipstick test by patients' self-assessment for urinary tract infection (UTI) screening and to determine the validity of urine dipstick test. Rehabilitation Department, Srinagarind Hospital, Thailand. A diagnostic study. This study compared the urine dipstick test (index test) with the National Institute on Disability and Rehabilitation Research (NIDRR) criteria (gold standard test) in spinal cord injury (SCI) patients. The urine dipstick test informed positive and negative results. Besides the NIDRR criteria classified as UTI and no UTI. The interrater reliability was measured in the sense of Kappa whereas the validity of urine dipstick test was reported in terms of sensitivity, specificity, positive likelihood ratio (LR) (+LR), negative LR (-LR), positive predictive value (PPV), and negative predictive value (NPV). Out of the 56 participants, the kappa of urine dipstick test for leukocyte esterase, nitrite, and combined leukocyte esterase and nitrite were 0.09, 0.21, and 0.52, respectively. The nitrite urine dipstick test showed the highest sensitivity (90%). The combined leukocyte esterase and nitrite urine dipstick test gave the highest specificity (87%), PPV (60%), NPV (93%), and +LR (5.63). The interrater reliability of combined leukocyte esterase and nitrite urine dipstick test was moderate agreement. The combined leukocyte esterase and nitrite urine dipstick test showed high level of both sensitivity and specificity. The combined leukocyte esterase and nitrite urine dipstick test should be promoted for patients' self-assessment for UTI screening in SCI patients.
Sert Kuniyoshi, Fatima H.; Zellmer, Mark R.; Calvin, Andrew D.; Lopez-Jimenez, Francisco; Albuquerque, Felipe N.; van der Walt, Christelle; Trombetta, Ivani C; Caples, Sean M.; Shamsuzzaman, Abu S.; Bukartyk, Jan; Konecny, Tomas; Gami, Apoor S.; Kara, Tomas
2011-01-01
Background: The Berlin Questionnaire (BQ) has been used to identify patients at high risk for sleep-disordered breathing (SDB) in a variety of populations. However, there are no data regarding the validity of the BQ in detecting the presence of SDB in patients after myocardial infarction (MI). The aim of this study was to determine the performance of the BQ in patients after MI. Methods: We conducted a cross-sectional study of 99 patients who had an MI 1 to 3 months previously. The BQ was administered, scored using the published methods, and followed by completed overnight polysomnography as the “gold standard.” SDB was defined as an apnea-hypopnea index of ≥ 5 events/h. The sensitivity, specificity, and positive and negative predictive values of the BQ were calculated. Results: Of the 99 patients, the BQ identified 64 (65%) as being at high-risk for having SDB. Overnight polysomnography showed that 73 (73%) had SDB. The BQ sensitivity and specificity was 0.68 and 0.34, respectively, with a positive predictive value of 0.68 and a negative predictive value of 0.50. Positive and negative likelihood ratios were 1.27 and 0.68, respectively, and the BQ overall diagnostic accuracy was 63%. Using different apnea-hypopnea index cutoff values did not meaningfully alter these results. Conclusion: The BQ performed with modest sensitivity, but the specificity was poor, suggesting that the BQ is not ideal in identifying SDB in patients with a recent MI. PMID:21596794
González-Fernández, Doris; Pons, Emérita Del Carmen; Rueda, Delfina; Sinisterra, Odalis Teresa; Murillo, Enrique; Scott, Marilyn E; Koski, Kristine G
2017-06-02
The usefulness of C-reactive protein (CRP) as a non-specific marker of inflammation during pregnancy and lactation is unclear in impoverished populations where co-existing infections and vitamin deficiencies are common. This cross-sectional study in Panama recruited 120 pregnant and 99 lactating Ngäbe-Buglé women from 14 communities in rural Panama. Obstetric history, indoor wood smoke exposure, fieldwork, BMI, vitamins A, B 12 , D, and folic acid, and inflammation markers (CRP, neutrophil/lymphocyte ratio (NLR), plateletcrit and cytokines) were measured. Multiple regressions explored both associations of CRP with other inflammatory markers and associations of CRP and elevated CRP based on trimester-specific cut-offs with maternal factors, infections and vitamin deficiencies. CRP was higher in pregnancy (51.4 ± 4.7 nmol/L) than lactation (27.8 ± 3.5 nmol/L) and was elevated above trimester specific cut-offs in 21% of pregnant and 30% of lactating women. Vitamin deficiencies were common (vitamin A 29.6%; vitamin D 68.5%; vitamin B 12 68%; folic acid 25.5%) and over 50% of women had two or more concurrent deficiencies as well as multiple infections. Multiple regression models highlighted differences in variables associated with CRP between pregnancy and lactation. In pregnancy, CRP was positively associated with greater indoor wood smoke exposure, caries and hookworm and negatively associated with Ascaris and vaginal Lactobacillus and Bacteroides/Gardnerella scores. Consistent with this, greater wood smoke exposure, caries as well as higher diplococcal infection score increased the odds of trimester-elevated CRP concentrations whereas longer gestational age lowered the likelihood of a trimester-elevated CRP. During lactation, folic acid deficiency was associated with higher CRP whereas parity, number of eosinophils and Mobiluncus score were associated with lower CRP. Also, a higher BMI and Trichomonas vaginalis score increased the likelihood of an elevated CRP whereas higher parity and number of eosinophils were associated with lower likelihood of an elevated CRP. Infections both raise and lower CRP concentrations in pregnant and lactating mothers. Only folic acid deficiency during lactation was associated with higher CRP concentrations. Caution is required when interpreting CRP concentrations in pregnant and lactating women who have co-existing nutrient deficiencies and multiple infections.
Early pregnancy angiogenic markers and spontaneous abortion: an Odense Child Cohort study.
Andersen, Louise B; Dechend, Ralf; Karumanchi, S Ananth; Nielsen, Jan; Joergensen, Jan S; Jensen, Tina K; Christesen, Henrik T
2016-11-01
Spontaneous abortion is the most commonly observed adverse pregnancy outcome. The angiogenic factors soluble Fms-like kinase 1 and placental growth factor are critical for normal pregnancy and may be associated to spontaneous abortion. We investigated the association between maternal serum concentrations of soluble Fms-like kinase 1 and placental growth factor, and subsequent spontaneous abortion. In the prospective observational Odense Child Cohort, 1676 pregnant women donated serum in early pregnancy, gestational week <22 (median 83 days of gestation, interquartile range 71-103). Concentrations of soluble Fms-like kinase 1 and placental growth factor were determined with novel automated assays. Spontaneous abortion was defined as complete or incomplete spontaneous abortion, missed abortion, or blighted ovum <22+0 gestational weeks, and the prevalence was 3.52% (59 cases). The time-dependent effect of maternal serum concentrations of soluble Fms-like kinase 1 and placental growth factor on subsequent late first-trimester or second-trimester spontaneous abortion (n = 59) was evaluated using a Cox proportional hazards regression model, adjusting for body mass index, parity, season of blood sampling, and age. Furthermore, receiver operating characteristics were employed to identify predictive values and optimal cut-off values. In the adjusted Cox regression analysis, increasing continuous concentrations of both soluble Fms-like kinase 1 and placental growth factor were significantly associated with a decreased hazard ratio for spontaneous abortion: soluble Fms-like kinase 1, 0.996 (95% confidence interval, 0.995-0.997), and placental growth factor, 0.89 (95% confidence interval, 0.86-0.93). When analyzed by receiver operating characteristic cut-offs, women with soluble Fms-like kinase 1 <742 pg/mL had an odds ratio for spontaneous abortion of 12.1 (95% confidence interval, 6.64-22.2), positive predictive value of 11.70%, negative predictive value of 98.90%, positive likelihood ratio of 3.64 (3.07-4.32), and negative likelihood ratio of 0.30 (0.19-0.48). For placental growth factor <19.7 pg/mL, odds ratio was 13.2 (7.09-24.4), positive predictive value was 11.80%, negative predictive value was 99.0%, positive likelihood ratio was 3.68 (3.12-4.34), and negative likelihood ratio was 0.28 (0.17-0.45). In the sensitivity analysis of 54 spontaneous abortions matched 1:4 to controls on gestational age at blood sampling, the highest area under the curve was seen for soluble Fms-like kinase 1 in prediction of first-trimester spontaneous abortion, 0.898 (0.834-0.962), and at the optimum cut-off of 725 pg/mL, negative predictive value was 51.4%, positive predictive value was 94.6%, positive likelihood ratio was 4.04 (2.57-6.35), and negative likelihood ratio was 0.22 (0.09-0.54). A strong, novel prospective association was identified between lower concentrations of soluble Fms-like kinase 1 and placental growth factor measured in early pregnancy and spontaneous abortion. A soluble Fms-like kinase 1 cut-off <742 pg/mL in maternal serum was optimal to stratify women at high vs low risk of spontaneous abortion. The cause and effect of angiogenic factor alterations in spontaneous abortions remain to be elucidated. Copyright © 2016 Elsevier Inc. All rights reserved.
Handwriting individualization using distance and rarity
NASA Astrophysics Data System (ADS)
Tang, Yi; Srihari, Sargur; Srinivasan, Harish
2012-01-01
Forensic individualization is the task of associating observed evidence with a specific source. The likelihood ratio (LR) is a quantitative measure that expresses the degree of uncertainty in individualization, where the numerator represents the likelihood that the evidence corresponds to the known and the denominator the likelihood that it does not correspond to the known. Since the number of parameters needed to compute the LR is exponential with the number of feature measurements, a commonly used simplification is the use of likelihoods based on distance (or similarity) given the two alternative hypotheses. This paper proposes an intermediate method which decomposes the LR as the product of two factors, one based on distance and the other on rarity. It was evaluated using a data set of handwriting samples, by determining whether two writing samples were written by the same/different writer(s). The accuracy of the distance and rarity method, as measured by error rates, is significantly better than the distance method.
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.
Maximum Likelihood Compton Polarimetry with the Compton Spectrometer and Imager
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lowell, A. W.; Boggs, S. E; Chiu, C. L.
2017-10-20
Astrophysical polarization measurements in the soft gamma-ray band are becoming more feasible as detectors with high position and energy resolution are deployed. Previous work has shown that the minimum detectable polarization (MDP) of an ideal Compton polarimeter can be improved by ∼21% when an unbinned, maximum likelihood method (MLM) is used instead of the standard approach of fitting a sinusoid to a histogram of azimuthal scattering angles. Here we outline a procedure for implementing this maximum likelihood approach for real, nonideal polarimeters. As an example, we use the recent observation of GRB 160530A with the Compton Spectrometer and Imager. Wemore » find that the MDP for this observation is reduced by 20% when the MLM is used instead of the standard method.« less
USE OF DIAGNODENT® FOR DIAGNOSIS OF NON-CAVITATED OCCLUSALDENTIN CARIES
Costa, Ana Maria; de Paula, Lilian Marly; Bezerra, Ana Cristina Barreto
2008-01-01
The purpose of this study was to evaluate the use of a laser fluorescence device for detection of occlusal caries in permanent teeth. One hundred and ninety-nine non-cavitated teeth from 26 patients aged 10 to 13 years were selected. After dental prophylaxis, two previously calibrated dentists examined the teeth. Visual inspection, radiographic examination and laser measurements were performed under standardized conditions. The validation method was cavity preparation with a small cone-shaped diamond bur, when the two examiners agreed about the presence of dentin caries. It was found that the laser detection method produced high values of sensitivity (0.93) and specificity (0.75) and a moderate positive predictive value (0.63). The laser device showed the lowest value of likelihood ratio (3.68). Kappa coefficient showed good repeatability for all methods. Although the laser device had an acceptable performance, this equipment should be used as an adjunct method to visual inspection to avoid false positive results. PMID:19089284
Gajdoš, R; Pilný, J; Pokorná, A
2016-01-01
PURPOSE OF THE STUDY Injury to the scapholunate ligament is frequently associated with a fracture of the distal radius. At present neither a unified concept of treatment nor a standard method of diagnosis in these concomitant injuries is available. The aim of the study was to evaluate a group of surgically treated patients with distal radius fractures in order to assess a contribution of combined conventional X-ray and intra-operative fluoroscopic examinations to the diagnosis of associated lesions and to compare short-term functional outcomes of sugically treated patients with those of patients treated conservatively. MATERIAL AND METHODS A group of patients undergoiong surgery for distal radius fractures using plate osteosynthesis was evaluated retrospectively. The peri-operative diagnosis of associated injury to the scapholunate ligament was based on pre-operative standard X-ray views and intra-operative fluoroscopy. The latter consisted of images of maximum radial and ulnar deviation as well as an image of the forearm in traction exerted manually along the long axis. All views were in postero-anterior projection. Results were read directly on the monitor of a fluoroscopic device after its calibration or were obtained by comparing the thickness of an attached Kirschner wire with the distance to be measured. Subsequently, pixels were converted to millimetres. When a scapholunate ligament injury was found and confirmed by examination of the contralateral wrist, the finding was verified by open reduction or arthroscopy. Both static and dynamic instabilities were treated together with the distal radius fracture at one-stage surgery. After surgery, the patients without ligament injury had the wrist immobilised for 4 weeks, then rehabilitation followed. In the patients with a damaged ligament, immobilisation in a short brace lasted until transarticular wires were removed. All patients were followed up for a year at least. At follow-up, the injured wrist was examined for signs of clinical instability of the scapholunate joint, functional outcome was assessed using the Mayo Wrist Score (MWS) and pain intensity was evaluated on the Visual Analoque Scale (VAS). Restriction in daily activities was rated by the Quick Disabilities of the Arm, Shoulder and Hand (QDASH) score and plain X-ray was done. If any of the results was not satisfactory, MRI examination was indicated. RESULTS Of a total of 265 patients, 35 had injury to the scapholunate joint, 16 had static instability diagnosed by a standard fluoroscopic examination and nine patients with an acute phase of injury remained undiagnosed. For detection of associated scapholunate injuries, a standard X-ray examination had sensitivity of 46%, specificity of 99%, accuracy of 92%, positive predictive value of 84%, negative predictive value of 92%, positive likelihood ratio = 35.05 and negative likelihood ratio = 0.55. Dynamic fluoroscopic examination showed sensitivity of 53%, specificity of 99%, accuracy of 95%, positive predictive value of 77%, negative predictive value of 96%, positive likelihood ratio = 36.49 and negative likelihood ratio = 0.48. Using the MWS system, no differences in the outcome of scapholunate instability treatment were found between the patients undergoing surgery and those treated conservatively (p=0.35). Statistically significant differences were detected in the evaluation of subjective parameters - both VAS and QDASH scores were better in the treated than non-treated patients (p=0.02 and p=0.04, respectively). DISCUSSION The high negative predictive values of both standard X-ray and intra-operative fluoroscopy showed that combined use of the two method is more relevant for excluding than for confirming an injury to the scapholunate ligament concomitant with distal radius fracture. Similarly, the low negative likelihood ratio showed that a negative result decreases the pre-test probability of concomitant injury. CONCLUSIONS Negative findings of scapholunate ligament injury on standard X-ray views and intra-operative fluoroscopic images make it unnecessary to perform any further intra-operative examination to detect injury to the scapholunate ligament. Positive findings require verification of the degree of injury by another intra-operative modality, most ideally by arthroscopy. Patients with untreated instability associated with distal radius fracture have, at short-term follow-up, no statistically significant differences in functioning of the injured extremity in comparison with treated patients. Subjectively, however, they feel more pain and more restriction in performing daily activities. Therefore, the treatment of an injured scapholunate ligament together with distal radius fracture at one-stage surgery seems to be a good alternative for the patient. Key words: distal radius fractures, scapholunate ligament, radiographic, diagnosis, outcome distal radius fracture.
Lin, Li-Rong; Tong, Man-Li; Fu, Zuo-Gen; Dan, Bing; Zheng, Wei-Hong; Zhang, Chang-Gong; Yang, Tian-Ci; Zhang, Zhong-Ying
2011-05-01
Syphilis remains as a worldwide public health problem; hence, it is necessary to develop a new diagnostic approach that is easier and faster than conventional tests. A new testing method to detect Treponema pallidum IgM (TP-IgM), named colloidal gold immunochromatography assay (GICA), is presented in place of fluorescent treponemal antibody absorption (FTA-Abs). TP-IgM was detected using GICA developed on syphilis-specific recombinant proteins TPN17 and TPN47. The FTA-Abs IgM test was set as the gold standard. A GICA TP-IgM test was performed to detect syphilis in 1208 patients who received recommended therapy for syphilis for more than 1 year at the Xiamen Center of Clinical Laboratory in China from June 2005 to May 2009. One hundred blood donors were set up as control. The sensitivity, specificity, positive predictive value, negative predictive value, positive likelihood ratio, and negative likelihood ratio were 98.21%, 99.04%, 93.75%, 99.73%, 102.3, and 0.018, respectively. Detection on 500 interference specimens indicated that the biological false-positive rate of the GICA test was extremely low and was free from other biological and chemical factors. The patients were divided into the following experimental groups based on the results of toluidine red unheated serum test (TRUST) and treponemal pallidum particle agglutination (TPPA): (1) the syphilis serofast reaction (SSR) group consisted of 411 cases with (+) TRUST and (+) TPPA, which exhibited no clinical manifestations of syphilis after 1 year of recommended syphilis treatment; (2) the serum cure group, which was further subdivided into group A, a group that consisted of 251 cases with (-) TRUST and (+) TPPA, and (3) group B, a group that consisted of 546 cases with (-) TRUST and (-) TPPA; and (4) the blood donor control group, which consisted of 100 healthy persons with (-) ELISA-TP and (-) TPPA. We used the FTA-Abs method and the GICA method to detect TP-IgM; the positive rate of TP-IgM in 411 SSR patients was 34.55% and 36.01%, respectively. However, in serum cure group A, the positive rate of TP-IgM was 10.36% and 11.16%, respectively. The χ(2) test revealed that there is a significant difference in the positive rate between these 2 groups (P < 0.01). The TP-IgM positive rate in the same group, as detected by the GICA method and the FTA-Abs method, had no significant difference in statistics. However, as detected by the GICA method and the FTA-Abs method, all the samples in serum cure group B and the control group were negative for TP-IgM. The TP-IgM-positive result demonstrated that active T. pallidum remained in the bodies of SSR patients. In summary, the characteristics of GICA TP-IgM correspond to that of FTA-Abs TP-IgM; this can be used as a serologic marker for the relapse and infection of syphilis in place of the conventional FTA-Abs IgM test. Copyright © 2011 Elsevier Inc. All rights reserved.
Likelihood for transcriptions in a genetic regulatory system under asymmetric stable Lévy noise
NASA Astrophysics Data System (ADS)
Wang, Hui; Cheng, Xiujun; Duan, Jinqiao; Kurths, Jürgen; Li, Xiaofan
2018-01-01
This work is devoted to investigating the evolution of concentration in a genetic regulation system, when the synthesis reaction rate is under additive and multiplicative asymmetric stable Lévy fluctuations. By focusing on the impact of skewness (i.e., non-symmetry) in the probability distributions of noise, we find that via examining the mean first exit time (MFET) and the first escape probability (FEP), the asymmetric fluctuations, interacting with nonlinearity in the system, lead to peculiar likelihood for transcription. This includes, in the additive noise case, realizing higher likelihood of transcription for larger positive skewness (i.e., asymmetry) index β, causing a stochastic bifurcation at the non-Gaussianity index value α = 1 (i.e., it is a separating point or line for the likelihood for transcription), and achieving a turning point at the threshold value β ≈ - 0.5 (i.e., beyond which the likelihood for transcription suddenly reversed for α values). The stochastic bifurcation and turning point phenomena do not occur in the symmetric noise case (β = 0). While in the multiplicative noise case, non-Gaussianity index value α = 1 is a separating point or line for both the MFET and the FEP. We also investigate the noise enhanced stability phenomenon. Additionally, we are able to specify the regions in the whole parameter space for the asymmetric noise, in which we attain desired likelihood for transcription. We have conducted a series of numerical experiments in "regulating" the likelihood of gene transcription by tuning asymmetric stable Lévy noise indexes. This work offers insights for possible ways of achieving gene regulation in experimental research.
Chon, Sung-Bin; Kwak, Young Ho; Hwang, Seung-Sik; Oh, Won Sup; Bae, Jun-Ho
2013-12-01
Detecting severe hyperkalemia is challenging. We explored its prevalence in symptomatic or extreme bradycardia and devised a diagnostic rule. This retrospective cross-sectional study included patients with symptomatic (heart rate [HR] ≤ 50/min with dyspnea, chest pain, altered mentality, dizziness/syncope/presyncope, general weakness, oliguria, or shock) or extreme (HR ≤ 40/min) bradycardia at an emergency department for 46 months. Risk factors for severe hyperkalemia were chosen by multiple logistic regression analysis from history (sex, age, comorbidities, and medications), vital signs, and electrocardiography (ECG; maximum precordial T-wave amplitude, PR, and QRS intervals). The derived diagnostic index was validated using bootstrapping method. Among the 169 participants enrolled, 87 (51.5%) were female. The mean (SD) age was 71.2 (12.5) years. Thirty-six (21.3%) had severe hyperkalemia. The diagnostic summed "maximum precordial T ≥ 8.5 mV (2)," "atrial fibrillation/junctional bradycardia (1)," "HR ≤ 42/min (1)," "diltiazem medication (2)," and "diabetes mellitus (1)." The C-statistics were 0.86 (0.80-0.93) and were validated. For scores of 4 or higher, sensitivity was 0.50, specificity was 0.92, and positive likelihood ratio was 6.02. The "ECG-only index," which sums the 3 ECG findings, had a sensitivity of 0.50, specificity of 0.90, and likelihood ratio (+) of 5.10 for scores of 3 or higher. Severe hyperkalemia is prevalent in symptomatic or extreme bradycardia and detectable by quantitative electrocardiographic parameters and history. © 2013.
Shen, Yongchun; Pang, Caishuang; Wu, Yanqiu; Li, Diandian; Wan, Chun; Liao, Zenglin; Yang, Ting; Chen, Lei; Wen, Fuqiang
2016-06-01
The usefulness of bronchoalveolar lavage fluid (BALF) CD4/CD8 ratio for diagnosing sarcoidosis has been reported in many studies with variable results. Therefore, we performed a meta-analysis to estimate the overall diagnostic accuracy of BALF CD4/CD8 ratio based on the bulk of published evidence. Studies published prior to June 2015 and indexed in PubMed, OVID, Web of Science, Scopus and other databases were evaluated for inclusion. Data on sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), and diagnostic odds ratio (DOR) were pooled from included studies. Summary receiver operating characteristic (SROC) curves were used to summarize overall test performance. Deeks's funnel plot was used to detect publication bias. Sixteen publications with 1885 subjects met our inclusion criteria and were included in this meta-analysis. Summary estimates of the diagnostic performance of the BALF CD4/CD8 ratio were as follows: sensitivity, 0.70 (95%CI 0.64-0.75); specificity, 0.83 (95%CI 0.78-0.86); PLR, 4.04 (95%CI 3.13-5.20); NLR, 0.36 (95%CI 0.30-0.44); and DOR, 11.17 (95%CI 7.31-17.07). The area under the SROC curve was 0.84 (95%CI 0.81-0.87). There was no evidence of publication bias. Measuring the BALF CD4/CD8 ratio may assist in the diagnosis of sarcoidosis when interpreted in parallel with other diagnostic factors. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.
Jin, Ting; Fei, Baoying; Zhang, Yu; He, Xujun
2017-01-01
Intestinal tuberculosis (ITB) and Crohn's disease (CD) are important differential diagnoses that can be difficult to distinguish. Polymerase chain reaction (PCR) for Mycobacterium tuberculosis (MTB) is an efficient and promising tool. This meta-analysis was performed to systematically and objectively assess the potential diagnostic accuracy and clinical value of PCR for MTB in distinguishing ITB from CD. We searched PubMed, Embase, Web of Science, Science Direct, and the Cochrane Library for eligible studies, and nine articles with 12 groups of data were identified. The included studies were subjected to quality assessment using the revised Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) tool. The summary estimates were as follows: sensitivity 0.47 (95% CI: 0.42-0.51); specificity 0.95 (95% CI: 0.93-0.97); the positive likelihood ratio (PLR) 10.68 (95% CI: 6.98-16.35); the negative likelihood ratio (NLR) 0.49 (95% CI: 0.33-0.71); and diagnostic odds ratio (DOR) 21.92 (95% CI: 13.17-36.48). The area under the curve (AUC) was 0.9311, with a Q* value of 0.8664. Heterogeneity was found in the NLR. The heterogeneity of the studies was evaluated by meta-regression analysis and subgroup analysis. The current evidence suggests that PCR for MTB is a promising and highly specific diagnostic method to distinguish ITB from CD. However, physicians should also keep in mind that negative results cannot exclude ITB for its low sensitivity. Additional prospective studies are needed to further evaluate the diagnostic accuracy of PCR.
Schöneberg, C; Tampier, S; Hussmann, B; Lendemans, S; Waydhas, C
2014-12-01
The objective of this systematic review was to investigate the diagnostic management in paediatric blunt abdominal injuries. A literature research was performed using following sources: MEDLINE, Embase and Cochrane. Where it was possible a meta-analysis was performed. Furthermore the level of evidence for all publications was assigned. Indicators for intraabdominal injury (IAI) were elevated liver transaminases, abnormal abdominal examinations, low systolic blood pressure, reduced haematocrit and microhematuria. Detecting IAI with focused assessment with sonography for trauma (FAST) had an overall sensitivity of 56.5 %, a specificity of 94.68 %, a positive likelihood ratio of 10.63 and a negative likelihood ratio of 0.46. The accuracy was 84.02 %. Among haemodynamically unstable children the sensitivity and specificity were 100 %. The overall prevalence of IAI and negative CT was 0.19 %. The NPV of abdominal CT for diagnosing IAI was 99.8 %. The laparotomy rate in patients with isolated intraperitoneal fluid (IIF) in one location was 3.48 % and 56.52 % in patients with IIF in more than one location. FAST as an isolated tool in the diagnostics after blunt abdominal injury is very uncertain, because of the modest sensitivity. Discharging children after blunt abdominal trauma with a negative abdominal CT scan seems to be safe. When IIF is detected on CT scan, it depends on the number of locations involved. If IIF is found only in 1 location, IAI is uncommon, while IIF in two or more locations results in a high laparotomy rate. Georg Thieme Verlag KG Stuttgart · New York.
Sotillo-Díaz, J C; Bermejo-López, E; García-Olivares, P; Peral-Gutiérrez, J A; Sancho-González, M; Guerrero-Sanz, J E
2014-01-01
To determine the role of plasma procalcitonin (PCT) levels in diagnosing ventilator-associated pneumonia. A systematic review of publications prospectively assessing the diagnostic role of PCT in ventilator-associated pneumonia was carried out. The search was performed using Medline, Embase, the Cochrane Collaboration and MEDION, with reviewing of the references of retrieved articles. We extracted data that allowed the calculation of sensitivity, specificity, likelihood ratios and diagnostic odds ratio. Intervention Metaregression was performed to determine whether exposure to previous antibiotic treatment, the time to occurrence of ventilator-associated pneumonia and the type of patients had an impact upon the diagnostic performance of procalcitonin. Seven studies were considered (373 patients, 434 episodes). We found no publication bias or threshold effect. High plasma PCT levels were associated to an increased risk of suffering ventilator-associated pneumonia (OR: 8.39; 95% CI: 5.4-12.6). The pooled data on sensitivity, specificity, positive and negative likelihood ratio, and diagnostic odds ratio found were 76% (69-82), 79% (74-84), 4.35 (2.48-7.62), 0.26 (0.15-0.46) and 17.9 (10.1-31.7), respectively. Diagnostic yield was modified by prior exposure to antibiotics (rDOR 0.11, 0.02-0.069), but not by the type of critically ill patient or the time to occurrence of ventilator-associated pneumonia. Our results suggest that PCT provides additional information on the risk of VAP. Inclusion of PCT in diagnostic algorithms could improve their effectiveness. Copyright © 2013 Elsevier España, S.L. and SEMICYUC. All rights reserved.
Li, Yan-Wei; Zhou, Le-Shan; Li, Xing
2017-03-15
Fever is the most common complaint in the pediatric and emergency departments. Caregivers prefer to detect fever in their children by tactile assessment. To summarize the evidence on the accuracy of caregivers' tactile assessment for detecting fever in children. We performed a literature search of Cochrane Library, PubMed, Web of Knowledge, EMBASE (ovid), EBSCO and Google Scholar, without restriction of publication date, to identify English articles assessing caregivers' ability of detecting fever in children by tactile assessment. Quality assessment was based on the 2011 Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) criteria. Pooled estimates of sensitivity and specificity were calculated with use of bivariate model and summary receiver operation characteristics plots for meta-analysis. 11 articles were included in our analysis. The summary estimates for tactile assessment as a diagnostic tool revealed a sensitivity of 87.5% (95% CI 79.3% to 92.8%) and specificity of 54.6% (95% CI 38.5% to 69.9%). The pooled positive likelihood ratio was 1.93 (95% CI 1.39 to 2.67) and negative likelihood ratio was 0.23 (95% CI 0.15 to 0.36). Area under curve was 0.82 (95% CI 0.7 to 0.85). The pooled diagnostic odds ratio was 8.46 (95% CI 4.54 to 15.76). Tactile assessment of fever in children by palpation has moderate diagnostic value. Caregivers' assessment as "no fever" by touch is quite accurate in ruling out fever, while assessment as "fever" can be considered but needs confirmation.
Sartelli, Massimo; Abu-Zidan, Fikri M; Catena, Fausto; Griffiths, Ewen A; Di Saverio, Salomone; Coimbra, Raul; Ordoñez, Carlos A; Leppaniemi, Ari; Fraga, Gustavo P; Coccolini, Federico; Agresta, Ferdinando; Abbas, Asrhaf; Abdel Kader, Saleh; Agboola, John; Amhed, Adamu; Ajibade, Adesina; Akkucuk, Seckin; Alharthi, Bandar; Anyfantakis, Dimitrios; Augustin, Goran; Baiocchi, Gianluca; Bala, Miklosh; Baraket, Oussama; Bayrak, Savas; Bellanova, Giovanni; Beltràn, Marcelo A; Bini, Roberto; Boal, Matthew; Borodach, Andrey V; Bouliaris, Konstantinos; Branger, Frederic; Brunelli, Daniele; Catani, Marco; Che Jusoh, Asri; Chichom-Mefire, Alain; Cocorullo, Gianfranco; Colak, Elif; Costa, David; Costa, Silvia; Cui, Yunfeng; Curca, Geanina Loredana; Curry, Terry; Das, Koray; Delibegovic, Samir; Demetrashvili, Zaza; Di Carlo, Isidoro; Drozdova, Nadezda; El Zalabany, Tamer; Enani, Mushira Abdulaziz; Faro, Mario; Gachabayov, Mahir; Giménez Maurel, Teresa; Gkiokas, Georgios; Gomes, Carlos Augusto; Gonsaga, Ricardo Alessandro Teixeira; Guercioni, Gianluca; Guner, Ali; Gupta, Sanjay; Gutierrez, Sandra; Hutan, Martin; Ioannidis, Orestis; Isik, Arda; Izawa, Yoshimitsu; Jain, Sumita A; Jokubauskas, Mantas; Karamarkovic, Aleksandar; Kauhanen, Saila; Kaushik, Robin; Kenig, Jakub; Khokha, Vladimir; Kim, Jae Il; Kong, Victor; Koshy, Renol; Krasniqi, Avidyl; Kshirsagar, Ashok; Kuliesius, Zygimantas; Lasithiotakis, Konstantinos; Leão, Pedro; Lee, Jae Gil; Leon, Miguel; Lizarazu Pérez, Aintzane; Lohsiriwat, Varut; López-Tomassetti Fernandez, Eudaldo; Lostoridis, Eftychios; Mn, Raghuveer; Major, Piotr; Marinis, Athanasios; Marrelli, Daniele; Martinez-Perez, Aleix; Marwah, Sanjay; McFarlane, Michael; Melo, Renato Bessa; Mesina, Cristian; Michalopoulos, Nick; Moldovanu, Radu; Mouaqit, Ouadii; Munyika, Akutu; Negoi, Ionut; Nikolopoulos, Ioannis; Nita, Gabriela Elisa; Olaoye, Iyiade; Omari, Abdelkarim; Ossa, Paola Rodríguez; Ozkan, Zeynep; Padmakumar, Ramakrishnapillai; Pata, Francesco; Pereira Junior, Gerson Alves; Pereira, Jorge; Pintar, Tadeja; Pouggouras, Konstantinos; Prabhu, Vinod; Rausei, Stefano; Rems, Miran; Rios-Cruz, Daniel; Sakakushev, Boris; Sánchez de Molina, Maria Luisa; Seretis, Charampolos; Shelat, Vishal; Simões, Romeo Lages; Sinibaldi, Giovanni; Skrovina, Matej; Smirnov, Dmitry; Spyropoulos, Charalampos; Tepp, Jaan; Tezcaner, Tugan; Tolonen, Matti; Torba, Myftar; Ulrych, Jan; Uzunoglu, Mustafa Yener; van Dellen, David; van Ramshorst, Gabrielle H; Vasquez, Giorgio; Venara, Aurélien; Vereczkei, Andras; Vettoretto, Nereo; Vlad, Nutu; Yadav, Sanjay Kumar; Yilmaz, Tonguç Utku; Yuan, Kuo-Ching; Zachariah, Sanoop Koshy; Zida, Maurice; Zilinskas, Justas; Ansaloni, Luca
2015-01-01
To validate a new practical Sepsis Severity Score for patients with complicated intra-abdominal infections (cIAIs) including the clinical conditions at the admission (severe sepsis/septic shock), the origin of the cIAIs, the delay in source control, the setting of acquisition and any risk factors such as age and immunosuppression. The WISS study (WSES cIAIs Score Study) is a multicenter observational study underwent in 132 medical institutions worldwide during a four-month study period (October 2014-February 2015). Four thousand five hundred thirty-three patients with a mean age of 51.2 years (range 18-99) were enrolled in the WISS study. Univariate analysis has shown that all factors that were previously included in the WSES Sepsis Severity Score were highly statistically significant between those who died and those who survived (p < 0.0001). The multivariate logistic regression model was highly significant (p < 0.0001, R2 = 0.54) and showed that all these factors were independent in predicting mortality of sepsis. Receiver Operator Curve has shown that the WSES Severity Sepsis Score had an excellent prediction for mortality. A score above 5.5 was the best predictor of mortality having a sensitivity of 89.2 %, a specificity of 83.5 % and a positive likelihood ratio of 5.4. WSES Sepsis Severity Score for patients with complicated Intra-abdominal infections can be used on global level. It has shown high sensitivity, specificity, and likelihood ratio that may help us in making clinical decisions.
Cui, Jiangyu; Zhou, Yumin; Tian, Jia; Wang, Xinwang; Zheng, Jingping; Zhong, Nanshan; Ran, Pixin
2012-12-01
COPD is often underdiagnosed in a primary care setting where the spirometry is unavailable. This study was aimed to develop a simple, economical and applicable model for COPD screening in those settings. First we established a discriminant function model based on Bayes' Rule by stepwise discriminant analysis, using the data from 243 COPD patients and 112 non-COPD subjects from our COPD survey in urban and rural communities and local primary care settings in Guangdong Province, China. We then used this model to discriminate COPD in additional 150 subjects (50 non-COPD and 100 COPD ones) who had been recruited by the same methods as used to have established the model. All participants completed pre- and post-bronchodilator spirometry and questionnaires. COPD was diagnosed according to the Global Initiative for Chronic Obstructive Lung Disease criteria. The sensitivity and specificity of the discriminant function model was assessed. THE ESTABLISHED DISCRIMINANT FUNCTION MODEL INCLUDED NINE VARIABLES: age, gender, smoking index, body mass index, occupational exposure, living environment, wheezing, cough and dyspnoea. The sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, accuracy and error rate of the function model to discriminate COPD were 89.00%, 82.00%, 4.94, 0.13, 86.66% and 13.34%, respectively. The accuracy and Kappa value of the function model to predict COPD stages were 70% and 0.61 (95% CI, 0.50 to 0.71). This discriminant function model may be used for COPD screening in primary care settings in China as an alternative option instead of spirometry.
Lirio, R B; Dondériz, I C; Pérez Abalo, M C
1992-08-01
The methodology of Receiver Operating Characteristic curves based on the signal detection model is extended to evaluate the accuracy of two-stage diagnostic strategies. A computer program is developed for the maximum likelihood estimation of parameters that characterize the sensitivity and specificity of two-stage classifiers according to this extended methodology. Its use is briefly illustrated with data collected in a two-stage screening for auditory defects.
Miller, Anne; Nightingale, Alison L; Sammon, Cormac J; Mahtani, Kamal R; Holt, Tim A; McHugh, Neil J; Luqmani, Raashid A
2015-10-01
To investigate the diagnostic accuracy of RF as a test for RA in primary care and its impact on referral times using the Clinical Practice Research Datalink. We identified all patients with a first RF test recorded in the Clinical Practice Research Datalink between 1 January 2000 and 31 December 2008 and those diagnosed with RA within 2 years of testing. We calculated likelihood ratios (LRs), sensitivity, specificity and predictive values of RF for a diagnosis of RA. We compared time to hospital referral in those testing positive and negative using Kaplan-Meier failure curves and log-rank tests. Of 62 436 first RF tests, 4679 (7.5%) were positive. There were 1753 incident cases of RA, of which 57.8% were seropositive. The positive LR for RF was 9.5 (95% CI 9.0, 10.0) and the negative LR was 0.5 (95% CI 0.4, 0.5). Sensitivity and specificity were 57.8% (95% CI 55.4%, 60.1%) and 93.9% (95% CI 93.7%, 94.1%) and the positive predictive value and negative predictive value were 21.4% (95% CI 20.3%, 22.6%) and 98.7% (95% CI 98.6%, 98.8%), respectively. Median time to first hospital contact after the first RF test in those with seropositive vs seronegative results was 54 days (95% CI 49, 58) vs 150 (95% CI 147, 152). Only 2.8% of patients undergoing RF testing were diagnosed with RA, suggesting that RF is used to screen patients with musculoskeletal symptoms rather than those with more specific features of RA. A positive RF test may be helpful in diagnosing RA in primary care but performs badly in excluding RA and may delay referral. © The Author 2015. Published by Oxford University Press on behalf of the British Society for Rheumatology. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
Sohng, Hee Yon; Kuniyuki, Alan; Edelson, Jane; Weir, Rosy Chang; Song, Hui; Tu, Shin-Ping
2013-01-01
Understanding and enhancing change capabilities, including Practice Adaptive Reserve (PAR), of Community Health Centers (CHCs) may mitigate cancer-related health disparities. Using stratified random sampling, we recruited 232 staff from seven CHCs serving Asian Pacific Islander communities to complete a self-administered survey. We performed multilevel regression analyses to examine PAR composite scores by CHC, position type, and number of years worked at their clinic. The mean PAR score was 0.7 (s.d. 0.14). Higher scores were associated with a greater perceived likelihood that clinic staff would participate in an evidence-based intervention (EBI). Constructs such as communication, clinic flow, sensemaking, change valence, and resource availability were positively associated with EBI implementation or trended toward significance. PAR scores are positively associated with perceived likelihood of clinic staff participation in cancer screening EBI. Future research is needed to determine PAR levels most conducive to implementing change and to developing interventions that enhance Adaptive Reserve.
Kelly, Rebecca E; Mansell, Warren; Wood, Alex M; Alatiq, Yousra; Dodd, Alyson; Searson, Ruth
2011-11-01
This research aimed to test whether positive, negative, or conflicting appraisals about activated mood states (e.g., energetic and high states) predicted bipolar disorder. A sample of individuals from clinical and control groups (171 with bipolar disorder, 42 with unipolar depression, and 64 controls) completed a measure of appraisals of internal states. High negative appraisals related to a higher likelihood of bipolar disorder irrespective of positive appraisals. High positive appraisals related to a higher likelihood of bipolar disorder only when negative appraisals were also high. Individuals were most likely to have bipolar disorder, as opposed to unipolar depression or no diagnosis, when they endorsed both extremely positive and extremely negative appraisals of the same, activated states. Appraisals of internal states were based on self-report. The results indicate that individuals with bipolar disorder tend to appraise activated, energetic internal states in opposing or conflicting ways, interpreting these states as both extremely positive and extremely negative. This may lead to contradictory attempts to regulate these states, which may in turn contribute to mood swing symptoms. Psychological therapy for mood swings and bipolar disorder should address extreme and conflicting appraisals of mood states. Copyright © 2011 Elsevier B.V. All rights reserved.
Genotyping and inflated type I error rate in genome-wide association case/control studies
Sampson, Joshua N; Zhao, Hongyu
2009-01-01
Background One common goal of a case/control genome wide association study (GWAS) is to find SNPs associated with a disease. Traditionally, the first step in such studies is to assign a genotype to each SNP in each subject, based on a statistic summarizing fluorescence measurements. When the distributions of the summary statistics are not well separated by genotype, the act of genotype assignment can lead to more potential problems than acknowledged by the literature. Results Specifically, we show that the proportions of each called genotype need not equal the true proportions in the population, even as the number of subjects grows infinitely large. The called genotypes for two subjects need not be independent, even when their true genotypes are independent. Consequently, p-values from tests of association can be anti-conservative, even when the distributions of the summary statistic for the cases and controls are identical. To address these problems, we propose two new tests designed to reduce the inflation in the type I error rate caused by these problems. The first algorithm, logiCALL, measures call quality by fully exploring the likelihood profile of intensity measurements, and the second algorithm avoids genotyping by using a likelihood ratio statistic. Conclusion Genotyping can introduce avoidable false positives in GWAS. PMID:19236714
A readers' guide to the interpretation of diagnostic test properties: clinical example of sepsis.
Fischer, Joachim E; Bachmann, Lucas M; Jaeschke, Roman
2003-07-01
One of the most challenging practical and daily problems in intensive care medicine is the interpretation of the results from diagnostic tests. In neonatology and pediatric intensive care the early diagnosis of potentially life-threatening infections is a particularly important issue. A plethora of tests have been suggested to improve diagnostic decision making in the clinical setting of infection which is a clinical example used in this article. Several criteria that are critical to evidence-based appraisal of published data are often not adhered to during the study or in reporting. To enhance the critical appraisal on articles on diagnostic tests we discuss various measures of test accuracy: sensitivity, specificity, receiver operating characteristic curves, positive and negative predictive values, likelihood ratios, pretest probability, posttest probability, and diagnostic odds ratio. We suggest the following minimal requirements for reporting on the diagnostic accuracy of tests: a plot of the raw data, multilevel likelihood ratios, the area under the receiver operating characteristic curve, and the cutoff yielding the highest discriminative ability. For critical appraisal it is mandatory to report confidence intervals for each of these measures. Moreover, to allow comparison to the readers' patient population authors should provide data on study population characteristics, in particular on the spectrum of diseases and illness severity.
Strand, Edythe A; McCauley, Rebecca J; Weigand, Stephen D; Stoeckel, Ruth E; Baas, Becky S
2013-04-01
In this article, the authors report reliability and validity evidence for the Dynamic Evaluation of Motor Speech Skill (DEMSS), a new test that uses dynamic assessment to aid in the differential diagnosis of childhood apraxia of speech (CAS). Participants were 81 children between 36 and 79 months of age who were referred to the Mayo Clinic for diagnosis of speech sound disorders. Children were given the DEMSS and a standard speech and language test battery as part of routine evaluations. Subsequently, intrajudge, interjudge, and test-retest reliability were evaluated for a subset of participants. Construct validity was explored for all 81 participants through the use of agglomerative cluster analysis, sensitivity measures, and likelihood ratios. The mean percentage of agreement for 171 judgments was 89% for test-retest reliability, 89% for intrajudge reliability, and 91% for interjudge reliability. Agglomerative hierarchical cluster analysis showed that total DEMSS scores largely differentiated clusters of children with CAS vs. mild CAS vs. other speech disorders. Positive and negative likelihood ratios and measures of sensitivity and specificity suggested that the DEMSS does not overdiagnose CAS but sometimes fails to identify children with CAS. The value of the DEMSS in differential diagnosis of severe speech impairments was supported on the basis of evidence of reliability and validity.
Jobst-Schwan, Tilman; Schmidt, Johanna Magdalena; Schneider, Ronen; Hoogstraten, Charlotte A; Ullmann, Jeremy F P; Schapiro, David; Majmundar, Amar J; Kolb, Amy; Eddy, Kaitlyn; Shril, Shirlee; Braun, Daniela A; Poduri, Annapurna; Hildebrandt, Friedhelm
2018-01-01
Until recently, morpholino oligonucleotides have been widely employed in zebrafish as an acute and efficient loss-of-function assay. However, off-target effects and reproducibility issues when compared to stable knockout lines have compromised their further use. Here we employed an acute CRISPR/Cas approach using multiple single guide RNAs targeting simultaneously different positions in two exemplar genes (osgep or tprkb) to increase the likelihood of generating mutations on both alleles in the injected F0 generation and to achieve a similar effect as morpholinos but with the reproducibility of stable lines. This multi single guide RNA approach resulted in median likelihoods for at least one mutation on each allele of >99% and sgRNA specific insertion/deletion profiles as revealed by deep-sequencing. Immunoblot showed a significant reduction for Osgep and Tprkb proteins. For both genes, the acute multi-sgRNA knockout recapitulated the microcephaly phenotype and reduction in survival that we observed previously in stable knockout lines, though milder in the acute multi-sgRNA knockout. Finally, we quantify the degree of mutagenesis by deep sequencing, and provide a mathematical model to quantitate the chance for a biallelic loss-of-function mutation. Our findings can be generalized to acute and stable CRISPR/Cas targeting for any zebrafish gene of interest.
Merrick, Alistair D; Grieve, Alan; Cogan, Nicola
2017-10-01
Despite increased risk of experiencing challenging behaviour, psychological impacts on community and residential staff supporting adults with autistic spectrum conditions are under-explored. Studies examining related roles indicate protective psychological factors may help maintain staff well-being. This study investigated relationships between motivational orientation (eudaimonic or hedonic), challenging behaviour frequency and type (physical, verbal or self-injurious) and psychological impacts (anxiety, depression and life satisfaction). Participants (N = 99) were recruited from six organisations providing autism-specific adult services within Scotland. A series of binary logistic regressions demonstrated weekly challenging behaviour exposure (compared to monthly or daily) significantly increased the likelihood of anxiety caseness. Increased eudaimonic motivation significantly reduced the likelihood of anxiety caseness while also predicting higher life satisfaction. Furthermore, having high levels of eudaimonic motivation appeared to moderate the impact of weekly challenging behaviour exposure on anxiety. No motivational orientation or challenging behaviour factor significantly predicted depression. This sample also demonstrated higher anxiety, lower depression and equivalent life satisfaction levels compared with general population norms. The results highlight the need for considering staff's motivational orientations, their frequency of exposure to challenging behaviour, and both positive and negative psychological outcomes, if seeking to accurately quantify or improve well-being in this staff population.
Henry, Brandon Michael; Roy, Joyeeta; Ramakrishnan, Piravin Kumar; Vikse, Jens; Tomaszewski, Krzysztof A; Walocha, Jerzy A
2016-07-01
Several studies have explored the use of serum procalcitonin (PCT) in differentiating between bacterial and viral etiologies in children with suspected meningitis. We pooled these studies into a meta-analysis to determine the PCT diagnostic accuracy. All major databases were searched through March 2015. No date or language restrictions were applied. Eight studies (n = 616 pediatric patients) were included. Serum PCT assay was found to be very accurate for differentiating the etiology of pediatric meningitis with pooled sensitivity and specificity of 0.96 (95% CI = 0.92-0.98) and 0.89 (95% CI = 0.86-0.92), respectively. The pooled positive likelihood ratio, negative likelihood ratio, diagnostic odds ratio (DOR), and area under the curve (AUC) for PCT were 7.5 (95% CI = 5.6-10.1), 0.08(95% CI = 0.04-0.14), 142.3 (95% CI = 59.5-340.4), and 0.97 (SE = 0.01), respectively. In 6 studies, PCT was found to be superior than CRP, whose DOR was only 16.7 (95%CI = 8.8-31.7). Our meta-analysis demonstrates that serum PCT assay is a highly accurate and powerful test for rapidly differentiating between bacterial and viral meningitis in children. © The Author(s) 2015.
A Genre-Specific Investigation of Video Game Engagement and Problem Play in the Early Life Course
Ream, Geoffrey L.; Elliott, Luther C.; Dunlap, Eloise
2013-01-01
This study explored predictors of engagement with specific video game genres, and degree of problem play experienced by players of specific genres, during the early life course. Video game players ages 18–29 (n = 692) were recruited in and around video game retail outlets, arcades, conventions, and other video game related contexts in New York City. Participants completed a Computer-Assisted Personal Interview (CAPI) of contemporaneous demographic and personality measures and a Life-History Calendar (LHC) measuring video gaming, school/work engagement, and caffeine and sugar consumption for each year of life ages 6 - present. Findings were that likelihood of engagement with most genres rose during childhood, peaked at some point during the second decade of life, and declined through emerging adulthood. Cohorts effects on engagement also emerged which were probably attributable to changes in the availability and popularity of various genres over the 12-year age range of our participants. The relationship between age and problem play of most genres was either negative or non-significant. Sensation-seeking was the only consistent positive predictor of problem play. Relationships between other variables and engagement with and problem play of specific genres are discussed in detail. PMID:24688802
[Functional endoscopic evaluation of swallowing in infants with deglutition disorders].
Partida-Justo, I; Israel Grijalva-Otero, J E; Ramírez-Figueroa, J L; Sepúlveda-Vildosola, A C; Zurita-Cruz, J N
2017-10-25
Functional endoscopic evaluation of swallowing (FEES) is a recognized method for Deglutition Disorders (DD) in adults, with anecdotal experience in children, obtaining not conclusive results. To compare the accuracy of test FEES in infants with high suspicion of altered DD seen in a third level hospital with the gold standard Videofluoroscopic (VF). The results and findings by FEES and VF of 66 children with clinical diagnosis of DD were compared. An estimate of the sensitivity and specificity of FEES was performed. As well as calculating positive predictive value (PPV), negative predictive value (NPV) and likelihood ratios. 60 patients enrolled, 4 and FEES showed high sensitivity to identify the presence of aspiration and penetration (9 98%) and high specificity for the arrest of spillage and waste (94% and 95%). Gastroesophageal reflux to make the diagnosis of DD with FEES had a sensitivity of 80% and specificity of 84%. Spill and penetration had the highest agreement with respect to the gold standard of 0.81. FEES in infants diagnosed with DD had a sensitivity of 80.8% and specificity 85.3%. 0696 concordance regarding to the VFD in the diagnosis of DD, and to identify suction stroke had a kappa of 0815.
Guillén-Solà, Anna; Marco, Ester; Martínez-Orfila, Joan; Donaire Mejías, M Fernanda; Depolo Passalacqua, Marina; Duarte, Esther; Escalada, Ferran
2013-01-01
Swallowing disorders affect up to 35-85% of patients with stroke. Dysphagia complications can lead to malnutrition, dehydration, bronchoaspirative pneumonia and death, and have impact on health care costs. To evaluate the clinical screening capacity of the Volume Viscosity Swallow Test (V-VST) for oropharyngeal dysphagia and aspiration in a homogeneous stroke patient sample. Cohort study of 52 stroke patients in a subacute phase. Piecemeal deglutition and oropharyngeal residue were considered signs of impaired efficacy and cough, fall in oxygen saturation and voice changes, signs of impaired safety. Sensitivity, specificity, positive and negative predictive values, accuracy and likelihood ratios were calculated for V-VST results and compared with those of videofluoroscopy (VFS), the gold standard for studies on swallowing disorders. The V-VST is a highly sensitive and specific test to detect aspiration with sensitivity of 88.2% and specificity of 71.4%; negative predictive value was 92.6%; accuracy index was 0.74. Sensitivity and specificity for penetration were 34.3% and 70.6%, respectively; accuracy was 32%. The V-VST is low in cost, easy to use and very sensitive, meeting the requirements of oropharyngeal dysphagia and aspiration screening test in subacute stroke patients.
A Genre-Specific Investigation of Video Game Engagement and Problem Play in the Early Life Course.
Ream, Geoffrey L; Elliott, Luther C; Dunlap, Eloise
2013-05-21
This study explored predictors of engagement with specific video game genres, and degree of problem play experienced by players of specific genres, during the early life course. Video game players ages 18-29 (n = 692) were recruited in and around video game retail outlets, arcades, conventions, and other video game related contexts in New York City. Participants completed a Computer-Assisted Personal Interview (CAPI) of contemporaneous demographic and personality measures and a Life-History Calendar (LHC) measuring video gaming, school/work engagement, and caffeine and sugar consumption for each year of life ages 6 - present. Findings were that likelihood of engagement with most genres rose during childhood, peaked at some point during the second decade of life, and declined through emerging adulthood. Cohorts effects on engagement also emerged which were probably attributable to changes in the availability and popularity of various genres over the 12-year age range of our participants. The relationship between age and problem play of most genres was either negative or non-significant. Sensation-seeking was the only consistent positive predictor of problem play. Relationships between other variables and engagement with and problem play of specific genres are discussed in detail.
Salvador, Fernando; Sulleiro, Elena; Piron, Maria; Sánchez-Montalvá, Adrián; Sauleda, Silvia; Molina-Morant, Daniel; Moure, Zaira; Molina, Israel
2017-11-01
In a previous study performed by our group, Strongyloides stercoralis infection in patients with Chagas disease was associated with higher proportion of Trypanosoma cruzi DNA detection in peripheral blood. The aim of the study was to confirm this association in a larger cohort of patients. Cross-sectional study of all patients with Chagas disease diagnosed from 2005 to 2015 during blood donation at the Catalan Blood Bank. Demographic data and T. cruzi RT-PCR were collected. S. stercoralis infection diagnosis was based on a serological test. Two hundred and two blood donors were included. T. cruzi RT-PCR was positive in 72 (35.6%) patients, and S. stercoralis serology was positive in 22 (10.9%) patients. Patients with positive S. stercoralis serology had higher proportion of positive T. cruzi RT-PCR than those with negative serology (54.5% vs. 33.3%, P = 0.050), and the difference increased when taking a serological index cut-off of 2.5, which increases the specificity of the test to detect a confirmed strongyloidiasis (60% vs. 33%, P = 0.017). Patients with Chagas disease with positive S. stercoralis serology had higher proportion of positive T. cruzi RT-PCR in peripheral blood than those with negative serology, which reflects the potential immunomodulatory effects of S. stercoralis in T. cruzi co-infected patients. © 2017 John Wiley & Sons Ltd.
Richards, David; Brealey, Stephen; Hewitt, Catherine
2007-01-01
Objective To summarize the psychometric properties of the PHQ2 and PHQ9 as screening instruments for depression. Interventions We identified 17 validation studies conducted in primary care; medical outpatients; and specialist medical services (cardiology, gynecology, stroke, dermatology, head injury, and otolaryngology). Electronic databases from 1994 to February 2007 (MEDLINE, PsycLIT, EMBASE, CINAHL, Cochrane registers) plus study reference lists have been used for this study. Translations included US English, Dutch, Italian, Spanish, German and Arabic). Summary sensitivity, specificity, likelihood and diagnostic odds ratios (OR) against a gold standard (DSM-IV) Major Depressive Disorder (MDD) were calculated for each study. We used random effects bivariate meta-analysis at recommended cut points to produce summary receiver–operator characteristic (sROC) curves. We explored heterogeneity with metaregression. Measurements and Main Results Fourteen studies (5,026 participants) validated the PHQ9 against MDD: sensitivity = 0.80 (95% CI 0.71–0.87); specificity = 0.92 (95% CI 0.88–0.95); positive likelihood ratio = 10.12 (95% CI 6.52–15.67); negative likelihood ratio = 0.22 (0.15 to 0.32). There was substantial heterogeneity (Diagnostic Odds Ratio heterogeneity I2 = 82%), which was not explained by study setting (primary care versus general hospital); method of scoring (cutoff ≥ 10 versus “diagnostic algorithm”); or study quality (blinded versus unblinded). The diagnostic validity of the PHQ2 was only validated in 3 studies and showed wide variability in sensitivity. Conclusions The PHQ9 is acceptable, and as good as longer clinician-administered instruments in a range of settings, countries, and populations. More research is needed to validate the PHQ2 to see if its diagnostic properties approach those of the PHQ9. PMID:17874169
Libin, Alexander V.; Wang, Hong; Swain, Sandra M.
2012-01-01
Purpose. Barriers to clinical trial participation among African American cancer patients are well characterized in the literature. Attitudinal barriers encompassing fear, distrust, and concerns about ethical misconduct are also well documented. To increase trial accrual, these attitudes must be adequately addressed, yet there remains a lack of targeted interventions toward this end. We developed a 15-minute culturally targeted video designed to impact six specific attitudes of African American cancer patients toward therapeutic trials. We conducted a pilot study to test in the first such intervention to increase intention to enroll. Patients and Methods. The primary study outcome was self-reported likelihood to participate in a therapeutic trial. Using a mixed methods approach, we developed the Attitudes and Intention to Enroll in Therapeutic Clinical Trials (AIET) instrument, a 30-item questionnaire measuring six attitudinal barriers to African American trial participation. We enrolled 108 eligible active treatment patients at a large urban cancer institute. McNemar's test for matched pairs was used to assess changes in attitudes and likelihood to enroll in a clinical trial at baseline and immediately after the video. Pre- and post-video AIET summative scores were analyzed by paired t-test for each attitudinal barrier. Results. Patients' likelihood of enrolling in a clinical trial significantly increased post-video with 36% of the sample showing positive changes in intention [McNemar's χ2 = 33.39, p < .001]. Paired t-tests showed significant changes in all six attitudinal barriers measured via AIET summative scores from pre- to post-video. Conclusion. These data suggest utility of our video for increasing African American participation in clinical trials. PMID:22639112
Health insurance coverage among disabled Medicare enrollees
Rubin, Jeffrey I.; Wilcox-Gök, Virginia
1991-01-01
In this article, we use the Survey of Income and Program Participation to identify patterns of non-Medicare insurance coverage among disabled Medicare enrollees. Compared with the aged, the disabled are less likely to have private insurance coverage and more likely to have Medicaid. Probit analysis of the determinants of private insurance for disabled Medicare enrollees shows that income, education, marital status, sex, and having an employed family member are positively related to the likelihood of having private health insurance, whereas age and the probability of Medicaid enrollment are negatively related to this likelihood. PMID:10170806
User's manual for MMLE3, a general FORTRAN program for maximum likelihood parameter estimation
NASA Technical Reports Server (NTRS)
Maine, R. E.; Iliff, K. W.
1980-01-01
A user's manual for the FORTRAN IV computer program MMLE3 is described. It is a maximum likelihood parameter estimation program capable of handling general bilinear dynamic equations of arbitrary order with measurement noise and/or state noise (process noise). The theory and use of the program is described. The basic MMLE3 program is quite general and, therefore, applicable to a wide variety of problems. The basic program can interact with a set of user written problem specific routines to simplify the use of the program on specific systems. A set of user routines for the aircraft stability and control derivative estimation problem is provided with the program.
Validation of rapid suicidality screening in epilepsy using the NDDIE.
Mula, Marco; McGonigal, Aileen; Micoulaud-Franchi, Jean-Arthur; May, Theodor W; Labudda, Kirsten; Brandt, Christian
2016-06-01
Standard mortality ratio for suicide in patients with epilepsy is three times higher than in the general population, and such a risk remains high even after adjusting for clinical and socioeconomic factors. It is thus important to have suitable screening instruments and to implement care pathways for suicide prevention in every epilepsy center. The aim of this study is to validate the use of the Neurological Disorder Depression Inventory for Epilepsy (NDDIE) as a suicidality-screening instrument. The study sample included adult patients with epilepsy assessed with the Mini International Neuropsychiatric Interview (MINI) and the NDDIE. A high suicidality risk according to the Suicidality Module of the MINI was considered the gold standard. Receiver operating characteristic analyses for NDDIE total and individual item scores were computed and subsequently compared using a nonparametric approach. The best possible cutoff was identified with the highest Youden index (J). Likelihood ratios were then computed, and specificity, sensitivity, positive, and negative predictive values calculated. The study sample consisted of 380 adult patients with epilepsy: 46.3% male; mean age was 39.4 ± 14.6; 76.7% had a diagnosis of focal epilepsy; mean age at onset of the epilepsy was 23.3 ± 17.5. According to the MINI, 74 patients (19.5%) fulfilled criteria for a major depressive episode and 19 (5%) presented a high suicidality risk. A score >2 (J = 0.751) for item 4 "I'd be better off dead" of the NDDIE displayed excellent psychometric properties with a good to excellent validity (area under the curve [AUC] 0.906; 95% confidence interval [CI] 0.820-0.992; p < 0.001), sensitivity 84.21% (95% CI 60.4-96.6), specificity 90.86% (95% CI 87.4-93.6), likelihood ratio+ 9.21 (95% CI 6.3-13.5), likelihood ratio- 0.17 (95% CI 0.06-0.50). Item 4 of the NDDIE has shown to be an excellent suicidality screening instrument allowing the development of further care pathways for suicide prevention in epilepsy centers. Wiley Periodicals, Inc. © 2016 International League Against Epilepsy.
Buying a Beauty Standard or Dreaming of a New Life? Expectations Associated with Media Ideals
ERIC Educational Resources Information Center
Engeln-Maddox, Renee
2006-01-01
This study explored college women's ideas regarding how their lives would change if their appearance were consistent with a media-supported female beauty ideal. Participants rated self-generated life changes they associated with looking like a media ideal in terms of likelihood and positivity. Women's tendency to link positive and likely life…
Policelli Smith, R; Gookin, J L; Smolski, W; Di Cicco, M F; Correa, M; Seiler, G S
2017-09-01
Bacterial cholecystitis often is diagnosed by combination of gallbladder ultrasound (US) findings and positive results of bile culture. The value of gallbladder US in determining the likelihood of bile bacterial infection in cats and dogs with suspected biliary disease is unknown. To determine the value of gallbladder US in predicting bile bacterial culture results, identify most common bacterial isolates from bile, and describe complications after cholecystocentesis in cats and dogs with suspected hepatobiliary disease. Cats (70) and dogs (202) that underwent an abdominal US and submission of bile for culture were included in the study. A cross-sectional study design was used to determine the association of gallbladder US abnormalities and the results of bile cultures, and complications of cholecystocentesis. Abnormal gallbladder US had high sensitivity (96%) but low specificity (49%) in cats with positive and negative results of bile bacterial culture, respectively. Cats with normal gallbladder US findings were unlikely to have positive bile bacterial culture (negative predictive value of 96%). Gallbladder US had lower sensitivity (81%), specificity (31%), positive predictive value (20%), and negative predictive value (88%) in dogs. The most common bacterial isolates were of enteric origin, the prevalence being higher in cats. Incidence of complications after cholecystocentesis was 3.4%. Gallbladder US has a high negative predictive value for bile culture results in cats. This modality is less predictive of infection in dogs. Percutaneous US-guided cholecystocentesis has a low complication rate. Copyright © 2017 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals, Inc. on behalf of the American College of Veterinary Internal Medicine.
Carim, Kellie J; Christianson, Kyle R; McKelvey, Kevin M; Pate, William M; Silver, Douglas B; Johnson, Brett M; Galloway, Benjamin T; Young, Michael K; Schwartz, Michael K
2016-01-01
The spread of Mysis diluviana, a small glacial relict crustacean, outside its native range has led to unintended shifts in the composition of native fish communities throughout western North America. As a result, biologists seek accurate methods of determining the presence of M. diluviana, especially at low densities or during the initial stages of an invasion. Environmental DNA (eDNA) provides one solution for detecting M. diluviana, but building eDNA markers that are both sensitive and species-specific is challenging when the distribution and taxonomy of closely related non-target taxa are poorly understood, published genetic data are sparse, and tissue samples are difficult to obtain. To address these issues, we developed a pair of independent eDNA markers to increase the likelihood of a positive detection of M. diluviana when present and reduce the probability of false positive detections from closely related non-target species. Because tissue samples of closely-related and possibly sympatric, non-target taxa could not be obtained, we used synthetic DNA sequences of closely related non-target species to test the specificity of eDNA markers. Both eDNA markers yielded positive detections from five waterbodies where M. diluviana was known to be present, and no detections in five others where this species was thought to be absent. Daytime samples from varying depths in one waterbody occupied by M. diluviana demonstrated that samples near the lake bottom produced 5 to more than 300 times as many eDNA copies as samples taken at other depths, but all samples tested positive regardless of depth.
Maldonado-Cárceles, Ana B; García-Medina, José; Torres-Cantero, Alberto M
2017-01-18
The overall purpose of this study is to compare the accuracy of physical examination (PE) versus ultrasonography (US) in people with arteriovenous fistula (AVF). This is a cross-sectional study with a total of 99 patients attended by the vascular radiology unit for AVF evaluation during January - March 2015. PE and ultrasonography were blinded performed by different radiologists. For complete and individual signs of PE, sensitivity, specificity, predictive positive (PPV) and negative (PNV) value, likelihood ratios (LR) and Cohen's κ value were measured. According to ultrasonography, the presence of stenosis was identified in 57 (58%) patients, and 61 (62%) by PE. The accuracy of PE for the diagnosis of AVF was sensitivity 82%, specificity 67%, PPV 77%, NPV 74%, LR 2.74 and 0.26. There was a moderate agreement beyond chance between PE and ultrasonography (κ = 0.5). PE has shown a moderate accuracy to detect stenosis. With non-ultrasonography availability Haemodialysis Units can get benefit to optimize VA survival and professionals should improve its basic skills.
Intervals for posttest probabilities: a comparison of 5 methods.
Mossman, D; Berger, J O
2001-01-01
Several medical articles discuss methods of constructing confidence intervals for single proportions and the likelihood ratio, but scant attention has been given to the systematic study of intervals for the posterior odds, or the positive predictive value, of a test. The authors describe 5 methods of constructing confidence intervals for posttest probabilities when estimates of sensitivity, specificity, and the pretest probability of a disorder are derived from empirical data. They then evaluate each method to determine how well the intervals' coverage properties correspond to their nominal value. When the estimates of pretest probabilities, sensitivity, and specificity are derived from more than 80 subjects and are not close to 0 or 1, all methods generate intervals with appropriate coverage properties. When these conditions are not met, however, the best-performing method is an objective Bayesian approach implemented by a simple simulation using a spreadsheet. Physicians and investigators can generate accurate confidence intervals for posttest probabilities in small-sample situations using the objective Bayesian approach.
Current perspectives on tree nut allergy: a review
Weinberger, Tamar; Sicherer, Scott
2018-01-01
Tree nut (TN) allergy is common and often severe. It has become an important health concern as availability and consumption have increased. Prevalence varies by age and geographic region and appears to have increased in children. Accidental ingestion of TNs is common. Unfortunately, there is a lower likelihood of resolution of TN allergy, roughly 10%. TN-specific skin tests and serum immunoglobulin E levels can help aid in the diagnosis of TN allergy, but a careful medical history is important because a positive test in isolation is not typically diagnostic. Component-resolved diagnostic tests are being increasingly utilized and may improve accuracy. Management consists of strict avoidance of the causal nut(s) and prompt treatment of symptoms upon accidental exposure. A specific consideration with regard to the management of TN allergy is the decision to avoid all TNs or only the TNs to which a patient is clinically allergic. There are currently no data on the primary or secondary prevention of TN allergy. Treatment strategies are being evaluated. PMID:29618933
Evaluation of Five Antibody Detection Tests for Diagnosis of Bovine Paratuberculosis
Collins, Michael T.; Wells, Scott J.; Petrini, Kristine R.; Collins, James E.; Schultz, Ronald D.; Whitlock, Robert H.
2005-01-01
Five diagnostic tests based on enzyme-linked immunosorbent assay (ELISA) technology for bovine paratuberculosis were evaluated by using individual serum or milk samples from 359 dairy cattle in seven paratuberculosis-free herds and 2,094 dairy cattle in seven Mycobacterium paratuberculosis-infected dairy herds. Three independent laboratories using three different culture procedures completed fecal cultures for M. paratuberculosis on these cattle and found 417 cows to be shedding M. paratuberculosis in their feces. An animal that was fecal culture positive for M. paratuberculosis by any of the three laboratories was considered a confirmed case of infection. The specificity of three ELISAs (two on serum and one on milk) was ≥99.8%. The specificity of the remaining two ELISAs, both done on serum, was 94.9 and 84.7%. Four of the five ELISAs evaluated produced similar sensitivity in detecting fecal culture-positive cattle (27.8 to 28.9%). Serum ELISA “D” had the lowest specificity (84.7%) and the highest sensitivity (44.5%), but if the cutoff value defining a positive test was changed from 125 to 250% (of the positive control) the sensitivity and specificity, 31.8 and 97.5%, respectively, were comparable to those of the other four assays. If the case definition for M. paratuberculosis infection was based on the culture results of a single laboratory instead of the combined results of three laboratories, ELISA sensitivity estimates were 45.7 to 50.0%. With the exception of ELISA D, assay agreement was high (kappa 0.66 to 0.85) for categorical assay interpretations (positive or negative), but linear regression of quantitative results showed low correlation coefficients (r2 = 0.40 to 0.68) due to the fact that ELISA results for some cows were high in one assay but low in another assay. Likelihood ratio analysis showed a direct relationship between the magnitude of ELISA result and the odds of a cow shedding M. paratuberculosis in its feces. If used judiciously and interpreted quantitatively, these ELISAs are useful tools in support of paratuberculosis control programs in dairy herds. PMID:15939741
Reliability of Soft Tissue Model Based Implant Surgical Guides; A Methodological Mistake.
Sabour, Siamak; Dastjerdi, Elahe Vahid
2012-08-20
Abstract We were interested to read the paper by Maney P and colleagues published in the July 2012 issue of J Oral Implantol. The authors aimed to assess the reliability of soft tissue model based implant surgical guides reported that the accuracy was evaluated using software. 1 I found the manuscript title of Maney P, et al. incorrect and misleading. Moreover, they reported twenty-two sites (46.81%) were considered accurate (13 of 24 maxillary and 9 of 23 mandibular sites). As the authors point out in their conclusion, Soft tissue models do not always provide sufficient accuracy for implant surgical guide fabrication.Reliability (precision) and validity (accuracy) are two different methodological issues in researches. Sensitivity, specificity, PPV, NPV, likelihood ratio positive (true positive/false negative) and likelihood ratio negative (false positive/ true negative) as well as odds ratio (true results\\false results - preferably more than 50) are among the tests to evaluate the validity (accuracy) of a single test compared to a gold standard.2-4 It is not clear that the reported twenty-two sites (46.81%) which were considered accurate related to which of the above mentioned estimates for validity analysis. Reliability (repeatability or reproducibility) is being assessed by different statistical tests such as Pearson r, least square and paired t.test which all of them are among common mistakes in reliability analysis 5. Briefly, for quantitative variable Intra Class Correlation Coefficient (ICC) and for qualitative variables weighted kappa should be used with caution because kappa has its own limitation too. Regarding reliability or agreement, it is good to know that for computing kappa value, just concordant cells are being considered, whereas discordant cells should also be taking into account in order to reach a correct estimation of agreement (Weighted kappa).2-4 As a take home message, for reliability and validity analysis, appropriate tests should be applied.
Burillo, Almudena; Rodríguez-Sánchez, Belén; Ramiro, Ana; Cercenado, Emilia; Rodríguez-Créixems, Marta; Bouza, Emilio
2014-01-01
Microbiological confirmation of a urinary tract infection (UTI) takes 24-48 h. In the meantime, patients are usually given empirical antibiotics, sometimes inappropriately. We assessed the feasibility of sequentially performing a Gram stain and MALDI-TOF MS mass spectrometry (MS) on urine samples to anticipate clinically useful information. In May-June 2012, we randomly selected 1000 urine samples from patients with suspected UTI. All were Gram stained and those yielding bacteria of a single morphotype were processed for MALDI-TOF MS. Our sequential algorithm was correlated with the standard semiquantitative urine culture result as follows: Match, the information provided was anticipative of culture result; Minor error, the information provided was partially anticipative of culture result; Major error, the information provided was incorrect, potentially leading to inappropriate changes in antimicrobial therapy. A positive culture was obtained in 242/1000 samples. The Gram stain revealed a single morphotype in 207 samples, which were subjected to MALDI-TOF MS. The diagnostic performance of the Gram stain was: sensitivity (Se) 81.3%, specificity (Sp) 93.2%, positive predictive value (PPV) 81.3%, negative predictive value (NPV) 93.2%, positive likelihood ratio (+LR) 11.91, negative likelihood ratio (-LR) 0.20 and accuracy 90.0% while that of MALDI-TOF MS was: Se 79.2%, Sp 73.5, +LR 2.99, -LR 0.28 and accuracy 78.3%. The use of both techniques provided information anticipative of the culture result in 82.7% of cases, information with minor errors in 13.4% and information with major errors in 3.9%. Results were available within 1 h. Our serial algorithm provided information that was consistent or showed minor errors for 96.1% of urine samples from patients with suspected UTI. The clinical impacts of this rapid UTI diagnosis strategy need to be assessed through indicators of adequacy of treatment such as a reduced time to appropriate empirical treatment or earlier withdrawal of unnecessary antibiotics.
The Diagnostic Value of the Clarke Sign in Assessing Chondromalacia Patella
Doberstein, Scott T; Romeyn, Richard L; Reineke, David M
2008-01-01
Context: Various techniques have been described for assessing conditions that cause pain at the patellofemoral (PF) joint. The Clarke sign is one such test, but the diagnostic value of this test in assessing chondromalacia patella is unknown. Objective: To (1) investigate the diagnostic value of the Clarke sign in assessing the presence of chondromalacia patella using arthroscopic examination of the PF joint as the “gold standard,” and (2) provide a historical perspective of the Clarke sign as a clinical diagnostic test. Design: Validation study. Setting: All patients of one of the investigators who had knee pain or injuries unrelated to the patellofemoral joint and were scheduled for arthroscopic surgery were recruited for this study. Patients or Other Participants: A total of 106 otherwise healthy individuals with no history of patellofemoral pain or dysfunction volunteered. Main Outcome Measure(s): The Clarke sign was performed on the surgical knee by a single investigator in the clinic before surgery. A positive test was indicated by the presence of pain sufficient to prevent the patient from maintaining a quadriceps muscle contraction against manual resistance for longer than 2 seconds. The preoperative result was compared with visual evidence of chondromalacia patella during arthroscopy. Results: Sensitivity was 0.39, specificity was 0.67, likelihood ratio for a positive test was 1.18, likelihood ratio for a negative test was 0.91, positive predictive value was 0.25, and negative predictive value was 0.80. Conclusions: Diagnostic validity values for the use of the Clarke sign in assessing chondromalacia patella were unsatisfactory, supporting suggestions that it has poor diagnostic value as a clinical examination technique. Additionally, an extensive search of the available literature for the Clarke sign reveals multiple problems with the test, causing significant confusion for clinicians. Therefore, the use of the Clarke sign as a routine part of a knee examination is not beneficial, and its use should be discontinued. PMID:18345345
The diagnostic value of the Clarke sign in assessing chondromalacia patella.
Doberstein, Scott T; Romeyn, Richard L; Reineke, David M
2008-01-01
Various techniques have been described for assessing conditions that cause pain at the patellofemoral (PF) joint. The Clarke sign is one such test, but the diagnostic value of this test in assessing chondromalacia patella is unknown. To (1) investigate the diagnostic value of the Clarke sign in assessing the presence of chondromalacia patella using arthroscopic examination of the PF joint as the "gold standard," and (2) provide a historical perspective of the Clarke sign as a clinical diagnostic test. Validation study. All patients of one of the investigators who had knee pain or injuries unrelated to the patellofemoral joint and were scheduled for arthroscopic surgery were recruited for this study. A total of 106 otherwise healthy individuals with no history of patellofemoral pain or dysfunction volunteered. The Clarke sign was performed on the surgical knee by a single investigator in the clinic before surgery. A positive test was indicated by the presence of pain sufficient to prevent the patient from maintaining a quadriceps muscle contraction against manual resistance for longer than 2 seconds. The preoperative result was compared with visual evidence of chondromalacia patella during arthroscopy. Sensitivity was 0.39, specificity was 0.67, likelihood ratio for a positive test was 1.18, likelihood ratio for a negative test was 0.91, positive predictive value was 0.25, and negative predictive value was 0.80. Diagnostic validity values for the use of the Clarke sign in assessing chondromalacia patella were unsatisfactory, supporting suggestions that it has poor diagnostic value as a clinical examination technique. Additionally, an extensive search of the available literature for the Clarke sign reveals multiple problems with the test, causing significant confusion for clinicians. Therefore, the use of the Clarke sign as a routine part of a knee examination is not beneficial, and its use should be discontinued.
Diffusion-weighted imaging determinants for acute ischemic stroke diagnosis in the emergency room.
Brunser, Alejandro M; Cavada, Gabriel; Venturelli, Paula Muñoz; Olavarría, Verónica; Rojo, Alexis; Almeida, Juan; Díaz, Violeta; Hoppe, Arnold; Lavados, Pablo
2018-05-22
The aim of this study was to investigate the clinical-radiological determinants of diffusion-weighted image (DWI) abnormalities in patients with suspected acute ischemic stroke (AIS) seen at the emergency room (ER). During the study period, 882 consecutive patients were screened at Clínica Alemana de Santiago, Chile; 786 had AIS and 711 (90.4%) were included. DWI demonstrated 87.3% sensitivity and 99.0% specificity, with a positive likelihood ratio of 79 and a negative likelihood ratio of 0.13 for the detection of AIS. In the univariate analysis, a positive DWI in AIS was associated with admission National Institute of Health Stroke Scale (NIHSS) score (OR 1.09, 95% CI 1.04-1.1%), time from symptom onset to DWI (OR 1.03, 95% CI 1.01-1.05), presence of a relevant intracranial artery occlusion (OR 3.18, 95% CI 1.75-5.76), posterior circulation ischemia (OR 0.44, 95% CI 0.28-0.7), brainstem location of the AIS (OR 0.16, 95% CI 0.093-0.27), infratentorial location of AIS (OR 0.44, 95% CI 0.28-0.70), and lacunar (OR 0.27, 95% CI 0.11-0.68) or undetermined stroke etiology (OR 0.12, 95% CI 0.3-0.31). In multivariate analysis, only admission NIHSS score (OR 1.07, 95% CI 1.01-1.13), time from symptom onset to DWI (OR 1.04, 95% CI 1.01-1.13), brainstem location (OR 0.13, 95% CI 0.051-0.37), and lacunar (OR: 0.4, 95% CI 0.21-0.78) or undetermined etiology (OR: 0.4, 95% CI 0.22-0.78) remained independently associated. DWI detects AIS accurately; the positivity of these evaluations in the ER is associated only with NIHSS on admission, time to DWI, brainstem location, and AIS etiology.
Anticipating cognitive effort: roles of perceived error-likelihood and time demands.
Dunn, Timothy L; Inzlicht, Michael; Risko, Evan F
2017-11-13
Why are some actions evaluated as effortful? In the present set of experiments we address this question by examining individuals' perception of effort when faced with a trade-off between two putative cognitive costs: how much time a task takes vs. how error-prone it is. Specifically, we were interested in whether individuals anticipate engaging in a small amount of hard work (i.e., low time requirement, but high error-likelihood) vs. a large amount of easy work (i.e., high time requirement, but low error-likelihood) as being more effortful. In between-subject designs, Experiments 1 through 3 demonstrated that individuals anticipate options that are high in perceived error-likelihood (yet less time consuming) as more effortful than options that are perceived to be more time consuming (yet low in error-likelihood). Further, when asked to evaluate which of the two tasks was (a) more effortful, (b) more error-prone, and (c) more time consuming, effort-based and error-based choices closely tracked one another, but this was not the case for time-based choices. Utilizing a within-subject design, Experiment 4 demonstrated overall similar pattern of judgments as Experiments 1 through 3. However, both judgments of error-likelihood and time demand similarly predicted effort judgments. Results are discussed within the context of extant accounts of cognitive control, with considerations of how error-likelihood and time demands may independently and conjunctively factor into judgments of cognitive effort.
Smoker Reactivity to Cues: Effects on Craving and on Smoking behavior
Shiffman, Saul; Dunbar, Michael; Kirchner, Thomas; Li, Xiaoxue; Tindle, Hilary; Anderson, Stewart; Scholl, Sarah
2013-01-01
We assessed craving and smoking in response to smoking-relevant cues. 207 daily smokers viewed images related to one of six cue sets (cigarettes, positive and negative affect, alcohol, smoking prohibitions, and neutral cues) in separate sessions. Compared to neutral cues, cigarette cues significantly increased craving, and positive affect cues significantly decreased craving. When subjects were then allowed to smoke during continuing cue exposure, cues did not affect the likelihood of smoking or the amount smoked (number of cigarettes, number of puffs, puff time, or increased carbon monoxide). However, craving intensity predicted likelihood of smoking, latency to smoke, and amount smoked, with craving increases after cue exposure making significant independent contributions. Some craving effects were curvilinear, suggesting that they are subject to thresholds and might not be observed under some circumstances. PMID:22708884
Diagnostic accuracy of history and physical examination in bacterial acute rhinosinusitis.
Autio, Timo J; Koskenkorva, Timo; Närkiö, Mervi; Leino, Tuomo K; Koivunen, Petri; Alho, Olli-Pekka
2015-07-01
To evaluate the diagnostic accuracy of symptoms, the symptom progression pattern, and clinical signs in identifying bacterial acute rhinosinusitis (ARS). We conducted an inception cohort study among 50 military recruits with ARS. We collected symptoms daily from the onset of symptoms to approximately 10 days. At 9 to 10 days, standardized data on symptoms and physical findings were gathered. A positive culture of maxillary sinus aspirate was considered to be the reference standard for bacterial ARS. At 9 to 10 days, the presence or deterioration after 5 days of any of the symptoms could not be used to diagnose bacterial ARS. Toothache had an adequate positive likelihood ratio (positive likelihood ratio [LR+] 4.4) but was too rare to be used for screening. In contrast, several physical findings at 9 to 10 days were of more diagnostic use and frequent enough for screening. Moderate or profuse (vs. none/minimal) amount of secretion in nasal passage seen in anterior rhinoscopy satisfactorily either ruled in, if present (LR+ 3.2), or ruled out, if absent (negative likelihood ratio 0.2), bacterial ARS. If any secretion was seen in the posterior pharynx or middle meatus, the probability of bacterial ARS increased markedly (LR+ 5.3 and LR+ 11.0, respectively). We found symptoms or their change to be of little use in identifying bacterial ARS. In contrast, we observed several clinical findings after 9 to 10 days of symptoms to predict bacterial ARS quite accurately. © 2015 The American Laryngological, Rhinological and Otological Society, Inc.
The relationship of thought-action fusion to pathologicial worry and generalized anxiety disorder.
Hazlett-Stevens, Holly; Zucker, Bonnie G; Craske, Michelle G
2002-10-01
Meta-cognitive beliefs associated with pathological worry and generalized anxiety disorder (GAD) may encompass the likelihood subtype of thought-action fusion (TAF), the belief that one's thoughts can influence outside events. In the current study of 494 undergraduate college students, positive correlations between scores on the Penn State Worry Questionnaire (PSWQ) and the two Likelihood subscales of the TAF Scale were found, and participants endorsing at least some DSM-IV diagnostic criteria for GAD scored significantly higher on both TAF-Likelihood subscales than participants reporting no GAD symptoms. However, these TAF scales did not predict GAD diagnostic status with PSWQ included as a predictor. In contrast to previous research, the TAF-Moral scale did not correlate with worry. Relationships between TAF, pathological worry, and meta-cognition are discussed in relation to GAD.
Self-Esteem and the Reproduction of Social Class*
James, Spencer L.; Amato, Paul R.
2013-01-01
Objective Although prior research has demonstrated the multiple pathways through which socioeconomic attainment occurs, one unexplored avenue regards the role of psychological mechanisms such as self-esteem in this process. Method Using three waves of data from the National Survey of Families and Households (N = 1,952), we employed structural equation models to examine the relationship between parenting practices and attitudes, socioeconomic status, offspring's self-esteem, and the likelihood of offspring college attendance. Results Self-esteem was positively related to the likelihood of offspring's college attendance. Additionally, self-esteem was found to be a modest mediator of the relationship between parental educational expectations and parental income, respectively, and the likelihood of offspring completing or being currently enrolled in college. Conclusion Self-esteem may constitute one previously unconsidered mechanism for reproducing the class structure in the United States. PMID:25568500
Multi-atlas segmentation for abdominal organs with Gaussian mixture models
NASA Astrophysics Data System (ADS)
Burke, Ryan P.; Xu, Zhoubing; Lee, Christopher P.; Baucom, Rebeccah B.; Poulose, Benjamin K.; Abramson, Richard G.; Landman, Bennett A.
2015-03-01
Abdominal organ segmentation with clinically acquired computed tomography (CT) is drawing increasing interest in the medical imaging community. Gaussian mixture models (GMM) have been extensively used through medical segmentation, most notably in the brain for cerebrospinal fluid / gray matter / white matter differentiation. Because abdominal CT exhibit strong localized intensity characteristics, GMM have recently been incorporated in multi-stage abdominal segmentation algorithms. In the context of variable abdominal anatomy and rich algorithms, it is difficult to assess the marginal contribution of GMM. Herein, we characterize the efficacy of an a posteriori framework that integrates GMM of organ-wise intensity likelihood with spatial priors from multiple target-specific registered labels. In our study, we first manually labeled 100 CT images. Then, we assigned 40 images to use as training data for constructing target-specific spatial priors and intensity likelihoods. The remaining 60 images were evaluated as test targets for segmenting 12 abdominal organs. The overlap between the true and the automatic segmentations was measured by Dice similarity coefficient (DSC). A median improvement of 145% was achieved by integrating the GMM intensity likelihood against the specific spatial prior. The proposed framework opens the opportunities for abdominal organ segmentation by efficiently using both the spatial and appearance information from the atlases, and creates a benchmark for large-scale automatic abdominal segmentation.
VarBin, a novel method for classifying true and false positive variants in NGS data
2013-01-01
Background Variant discovery for rare genetic diseases using Illumina genome or exome sequencing involves screening of up to millions of variants to find only the one or few causative variant(s). Sequencing or alignment errors create "false positive" variants, which are often retained in the variant screening process. Methods to remove false positive variants often retain many false positive variants. This report presents VarBin, a method to prioritize variants based on a false positive variant likelihood prediction. Methods VarBin uses the Genome Analysis Toolkit variant calling software to calculate the variant-to-wild type genotype likelihood ratio at each variant change and position divided by read depth. The resulting Phred-scaled, likelihood-ratio by depth (PLRD) was used to segregate variants into 4 Bins with Bin 1 variants most likely true and Bin 4 most likely false positive. PLRD values were calculated for a proband of interest and 41 additional Illumina HiSeq, exome and whole genome samples (proband's family or unrelated samples). At variant sites without apparent sequencing or alignment error, wild type/non-variant calls cluster near -3 PLRD and variant calls typically cluster above 10 PLRD. Sites with systematic variant calling problems (evident by variant quality scores and biases as well as displayed on the iGV viewer) tend to have higher and more variable wild type/non-variant PLRD values. Depending on the separation of a proband's variant PLRD value from the cluster of wild type/non-variant PLRD values for background samples at the same variant change and position, the VarBin method's classification is assigned to each proband variant (Bin 1 to Bin 4). Results To assess VarBin performance, Sanger sequencing was performed on 98 variants in the proband and background samples. True variants were confirmed in 97% of Bin 1 variants, 30% of Bin 2, and 0% of Bin 3/Bin 4. Conclusions These data indicate that VarBin correctly classifies the majority of true variants as Bin 1 and Bin 3/4 contained only false positive variants. The "uncertain" Bin 2 contained both true and false positive variants. Future work will further differentiate the variants in Bin 2. PMID:24266885
Whiley, Phillip J.; Parsons, Michael T.; Leary, Jennifer; Tucker, Kathy; Warwick, Linda; Dopita, Belinda; Thorne, Heather; Lakhani, Sunil R.; Goldgar, David E.; Brown, Melissa A.; Spurdle, Amanda B.
2014-01-01
Rare exonic, non-truncating variants in known cancer susceptibility genes such as BRCA1 and BRCA2 are problematic for genetic counseling and clinical management of relevant families. This study used multifactorial likelihood analysis and/or bioinformatically-directed mRNA assays to assess pathogenicity of 19 BRCA1 or BRCA2 variants identified following patient referral to clinical genetic services. Two variants were considered to be pathogenic (Class 5). BRCA1:c.4484G> C(p.Arg1495Thr) was shown to result in aberrant mRNA transcripts predicted to encode truncated proteins. The BRCA1:c.122A>G(p.His41Arg) RING-domain variant was found from multifactorial likelihood analysis to have a posterior probability of pathogenicity of 0.995, a result consistent with existing protein functional assay data indicating lost BARD1 binding and ubiquitin ligase activity. Of the remaining variants, seven were determined to be not clinically significant (Class 1), nine were likely not pathogenic (Class 2), and one was uncertain (Class 3).These results have implications for genetic counseling and medical management of families carrying these specific variants. They also provide additional multifactorial likelihood variant classifications as reference to evaluate the sensitivity and specificity of bioinformatic prediction tools and/or functional assay data in future studies. PMID:24489791
Maximal likelihood correspondence estimation for face recognition across pose.
Li, Shaoxin; Liu, Xin; Chai, Xiujuan; Zhang, Haihong; Lao, Shihong; Shan, Shiguang
2014-10-01
Due to the misalignment of image features, the performance of many conventional face recognition methods degrades considerably in across pose scenario. To address this problem, many image matching-based methods are proposed to estimate semantic correspondence between faces in different poses. In this paper, we aim to solve two critical problems in previous image matching-based correspondence learning methods: 1) fail to fully exploit face specific structure information in correspondence estimation and 2) fail to learn personalized correspondence for each probe image. To this end, we first build a model, termed as morphable displacement field (MDF), to encode face specific structure information of semantic correspondence from a set of real samples of correspondences calculated from 3D face models. Then, we propose a maximal likelihood correspondence estimation (MLCE) method to learn personalized correspondence based on maximal likelihood frontal face assumption. After obtaining the semantic correspondence encoded in the learned displacement, we can synthesize virtual frontal images of the profile faces for subsequent recognition. Using linear discriminant analysis method with pixel-intensity features, state-of-the-art performance is achieved on three multipose benchmarks, i.e., CMU-PIE, FERET, and MultiPIE databases. Owe to the rational MDF regularization and the usage of novel maximal likelihood objective, the proposed MLCE method can reliably learn correspondence between faces in different poses even in complex wild environment, i.e., labeled face in the wild database.
Wadland, William C; Zubek, Valentina Bayer; Clerisme-Beaty, Emmanuelle M; Ríos-Bedoya, Carlos F; Yawn, Barbara P
2017-01-01
The purpose of this study was to identify patient-related factors that may explain the increased likelihood of receiving a respiratory-related clinician action in patients identified to be at risk for chronic obstructive pulmonary disease in a U.S.-based pragmatic study of chronic obstructive pulmonary disease screening. This post hoc analysis (conducted in 2014-2015) of the Screening, Evaluating and Assessing Rate Changes of Diagnosing Respiratory Conditions in Primary Care 1 (SEARCH1) study (conducted in 2010-2011), used the chronic obstructive pulmonary disease Population Screener questionnaire in 112 primary care practices. Anyone with a previous chronic obstructive pulmonary disease diagnosis was excluded. Multivariate logistic regression modeling was used to assess patient factors associated with the likelihood of receiving an respiratory-related clinician action following positive screening. Overall, 994 of 6,497 (15%) screened positive and were considered at risk for chronic obstructive pulmonary disease. However, only 187 of the 994 patients (19%) who screened positive received a respiratory-related clinician action. The chances of receiving a respiratory-related clinician action were significantly increased in patients who visited their physician with a respiratory issue (p<0.05) or had already been prescribed a respiratory medication (p<0.05). Most (81%) patients who screened positive or had a respiratory-related clinician action had one or more comorbidity, including cardiovascular disease (68%), diabetes (30%), depression/anxiety (26%), asthma (11%), and cancer (9%). Routine chronic obstructive pulmonary disease screening appears to promote respiratory-related clinician actions in patients with a high likelihood for disease who have respiratory complaints or already use prescribed respiratory medication. Copyright © 2016 American Journal of Preventive Medicine. Published by Elsevier Inc. All rights reserved.
Physician Bayesian updating from personal beliefs about the base rate and likelihood ratio.
Rottman, Benjamin Margolin
2017-02-01
Whether humans can accurately make decisions in line with Bayes' rule has been one of the most important yet contentious topics in cognitive psychology. Though a number of paradigms have been used for studying Bayesian updating, rarely have subjects been allowed to use their own preexisting beliefs about the prior and the likelihood. A study is reported in which physicians judged the posttest probability of a diagnosis for a patient vignette after receiving a test result, and the physicians' posttest judgments were compared to the normative posttest calculated from their own beliefs in the sensitivity and false positive rate of the test (likelihood ratio) and prior probability of the diagnosis. On the one hand, the posttest judgments were strongly related to the physicians' beliefs about both the prior probability as well as the likelihood ratio, and the priors were used considerably more strongly than in previous research. On the other hand, both the prior and the likelihoods were still not used quite as much as they should have been, and there was evidence of other nonnormative aspects to the updating, such as updating independent of the likelihood beliefs. By focusing on how physicians use their own prior beliefs for Bayesian updating, this study provides insight into how well experts perform probabilistic inference in settings in which they rely upon their own prior beliefs rather than experimenter-provided cues. It suggests that there is reason to be optimistic about experts' abilities, but that there is still considerable need for improvement.
Aggarwal, Rachna; Namjou, Bahram; Li, Shibo; D'Souza, Anil; Tsao, Betty P; Bruner, Benjamin F; James, Judith A; Scofield, R Hal
2010-07-01
Systemic lupus erythematosus (SLE) is more common among women than men, a ratio of about 10 to 1. We undertook this study to describe familial male SLE within a large familial SLE cohort. SLE families (2 or more patients) were identified from the Lupus Multiplex Registry and Repository. Genomic DNA and blood samples were obtained using standard methods. Autoantibodies were determined by multiple methods. Medical records were abstracted for SLE clinical data. Fluorescent in situ hybridization (FISH) was performed with X and Y centromere-specific probes, and a probe specific for the Toll-like receptor 7 gene on the X chromosome. Among 523 SLE families, we found 5 families in which all the SLE patients were male. FISH found no yaa gene equivalent in these families. SLE-unaffected primary female relatives from the 5 families with only-male SLE patients had a statistically increased rate of positive antinuclear antibodies compared to SLE-unaffected female relatives in other families. White men with SLE were 5 times more likely to have an offspring with SLE than White women with SLE, but there was no difference in this likelihood among Black men. Because women in the all-male families had positive antinuclear antibodies, and men are more likely to have children with SLE, these data suggest genetic susceptibility factors that act only in men.
Shandra, Carrie L.; Hogan, Dennis P.
2014-01-01
Previous research on the education-to-employment transition for students with disabilities has suggested that participation in school-to-work programs is positively associated with post-high school success. This article utilizes data from the National Longitudinal Survey of Youth 1997 (NLSY97) to extend these findings in several ways. First, we assess the efficacy of specific types of school-based and work-based initiatives, including job shadowing, mentoring, cooperative education, school-sponsored enterprise, technical preparation, internships, and career major. Next, we extend the usual focus on the employment outcomes of work status and financial compensation to consider job-specific information on the receipt of fringe benefits. Overall, results from longitudinal multivariate analyses suggest that transition initiatives are effective in facilitating vocational success for this population; however, different aspects of school-to-work programs are beneficial for different aspects of employment. School-based programs are positively associated with stable employment and full-time work while work-based programs most consistently increase the likelihood that youth with disabilities will be employed in jobs that provide fringe benefits. Analyses also indicate that – once individuals with disabilities are stably employed – they can be employed in “good” jobs that provide employee benefits. PMID:25309111
Leishmania Infection: Laboratory Diagnosing in the Absence of a “Gold Standard”
Rodríguez-Cortés, Alhelí; Ojeda, Ana; Francino, Olga; López-Fuertes, Laura; Timón, Marcos; Alberola, Jordi
2010-01-01
There is no gold standard for diagnosing leishmaniases. Our aim was to assess the operative validity of tests used in detecting Leishmania infection using samples from experimental infections, a reliable equivalent to the classic definition of gold standard. Without statistical differences, the highest sensitivity was achieved by protein A (ProtA), immunoglobulin (Ig)G2, indirect fluorescenece antibody test (IFAT), lymphocyte proliferation assay, quantitative real-time polymerase chain reaction of bone marrow (qPCR-BM), qPCR-Blood, and IgG; and the highest specificity by IgG1, IgM, IgA, qPCR-Blood, IgG, IgG2, and qPCR-BM. Maximum positive predictive value was obtained simultaneously by IgG2, qPCR-Blood, and IgG; and maximum negative predictive value by qPCR-BM. Best positive and negative likelihood ratios were obtained by IgG2. The test having the greatest, statistically significant, area under the receiver operating characteristics curve was IgG2 enzyme-linked immunosorbent assay (ELISA). Thus, according to the gold standard used, IFAT and qPCR are far from fulfilling the requirements to be considered gold standards, and the test showing the highest potential to detect Leishmania infection is Leishmania-specific ELISA IgG2. PMID:20134001
Leishmania infection: laboratory diagnosing in the absence of a "gold standard".
Rodríguez-Cortés, Alhelí; Ojeda, Ana; Francino, Olga; López-Fuertes, Laura; Timón, Marcos; Alberola, Jordi
2010-02-01
There is no gold standard for diagnosing leishmaniases. Our aim was to assess the operative validity of tests used in detecting Leishmania infection using samples from experimental infections, a reliable equivalent to the classic definition of gold standard. Without statistical differences, the highest sensitivity was achieved by protein A (ProtA), immunoglobulin (Ig)G2, indirect fluorescenece antibody test (IFAT), lymphocyte proliferation assay, quantitative real-time polymerase chain reaction of bone marrow (qPCR-BM), qPCR-Blood, and IgG; and the highest specificity by IgG1, IgM, IgA, qPCR-Blood, IgG, IgG2, and qPCR-BM. Maximum positive predictive value was obtained simultaneously by IgG2, qPCR-Blood, and IgG; and maximum negative predictive value by qPCR-BM. Best positive and negative likelihood ratios were obtained by IgG2. The test having the greatest, statistically significant, area under the receiver operating characteristics curve was IgG2 enzyme-linked immunosorbent assay (ELISA). Thus, according to the gold standard used, IFAT and qPCR are far from fulfilling the requirements to be considered gold standards, and the test showing the highest potential to detect Leishmania infection is Leishmania-specific ELISA IgG2.
Diagnostic inaccuracy of smartphone applications for melanoma detection.
Wolf, Joel A; Moreau, Jacqueline F; Akilov, Oleg; Patton, Timothy; English, Joseph C; Ho, Jonhan; Ferris, Laura K
2013-04-01
To measure the performance of smartphone applications that evaluate photographs of skin lesions and provide the user with feedback about the likelihood of malignancy. Case-control diagnostic accuracy study. Academic dermatology department. PARTICIPANTS AND MATERIALS: Digital clinical images of pigmented cutaneous lesions (60 melanoma and 128 benign control lesions) with a histologic diagnosis rendered by a board-certified dermatopathologist, obtained before biopsy from patients undergoing lesion removal as a part of routine care. Sensitivity, specificity, and positive and negative predictive values of 4 smartphone applications designed to aid nonclinician users in determining whether their skin lesion is benign or malignant. Sensitivity of the 4 tested applications ranged from 6.8% to 98.1%; specificity, 30.4% to 93.7%; positive predictive value, 33.3% to 42.1%; and negative predictive value, 65.4% to 97.0%. The highest sensitivity for melanoma diagnosis was observed for an application that sends the image directly to a board-certified dermatologist for analysis; the lowest, for applications that use automated algorithms to analyze images. The performance of smartphone applications in assessing melanoma risk is highly variable, and 3 of 4 smartphone applications incorrectly classified 30% or more of melanomas as unconcerning. Reliance on these applications, which are not subject to regulatory oversight, in lieu of medical consultation can delay the diagnosis of melanoma and harm users.
Jaimes, Fabián; Garcés, Jenny; Cuervo, Jorge; Ramírez, Federico; Ramírez, Jorge; Vargas, Andrea; Quintero, Claudia; Ochoa, Jorge; Tandioy, Fabio; Zapata, Láder; Estrada, Juan; Yepes, Maria; Leal, Hiulber
2003-08-01
Evaluation of the usefulness of criteria for systemic inflammatory response syndrome (SIRS) compared with the final diagnosis of infection in patients admitted to the emergency room of two university-based hospitals. Longitudinal cohort study. Hospital Universitario San Vicente de Paul and Hospital General de Medellín, Medellín, Colombia. PATIENTS. Seven hundred thirty-four patients with suspected infection as main diagnosis for admittance into the emergency room. Sensitivity, specificity, predictive values and likelihood ratios (LR) of SIRS criteria at admission were determined using, as gold standards, the diagnosis at the time of discharge based on clinical history and evolution, and microbiological confirmation of infection. SIRS criteria were met by 503 patients (68.5%); the discharge diagnosis of infection was found in 657 (89.4%) and 276 (37%) had microbiological confirmation. SIRS criteria exhibited a sensitivity of 69%, specificity of 35%, positive predictive value (PPV) of 90%, negative predictive value (NPV) of 12% and positive LR of 1.06. There were no differences between the two gold standards. The finding of two or more SIRS criteria was of little usefulness for diagnosis of infection. It is necessary to work with new criteria and probably with biological markers, in order to obtain a simple, precise and operative definition of the sepsis phenomenon.
ERIC Educational Resources Information Center
Jelicic, Helena; Bobek, Deborah L.; Phelps, Erin; Lerner, Richard M.; Lerner, Jacqueline V.
2007-01-01
Theories of positive youth development (PYD) regard such development as bases of both community contributions and lessened likelihood of risk/problem behaviors. Using data from the 4-H Study of PYD, we tested these expectations by examining if PYD in Grade 5 predicted both youth contributions and risk behaviors and depression in Grade 6. Results…
THESEUS: maximum likelihood superpositioning and analysis of macromolecular structures
Theobald, Douglas L.; Wuttke, Deborah S.
2008-01-01
Summary THESEUS is a command line program for performing maximum likelihood (ML) superpositions and analysis of macromolecular structures. While conventional superpositioning methods use ordinary least-squares (LS) as the optimization criterion, ML superpositions provide substantially improved accuracy by down-weighting variable structural regions and by correcting for correlations among atoms. ML superpositioning is robust and insensitive to the specific atoms included in the analysis, and thus it does not require subjective pruning of selected variable atomic coordinates. Output includes both likelihood-based and frequentist statistics for accurate evaluation of the adequacy of a superposition and for reliable analysis of structural similarities and differences. THESEUS performs principal components analysis for analyzing the complex correlations found among atoms within a structural ensemble. PMID:16777907
Autoimmune/Inflammatory Arthritis Associated Lymphomas: Who Is at Risk?
2016-01-01
Specific autoimmune and inflammatory rheumatic diseases have been associated with an increased risk of malignant lymphomas. Conditions such as rheumatoid arthritis (RA), primary Sjögren's syndrome (pSS), systemic lupus erythematosus (SLE), dermatomyositis, and celiac disease have been consistently linked to malignant lymphomas. Isolated cases of lymphomas associated with spondyloarthropathies and autoinflammatory diseases have also been reported. Direct association between autoimmunity and lymphomagenesis has been reinforced by large epidemiological studies. It is still uncertain whether disease specific determinants or phenotypic or treatment related characteristics increase likelihood of lymphomagenesis in these patients. For example, recent literature has indicated a positive correlation between severity of inflammation and risk of lymphomas among RA and Sjögren's syndrome patients. It is also debated whether specific lymphoma variants are more commonly seen in accordance with certain chronic autoimmune arthritis. Previous studies have revealed a higher incidence of diffuse large B-cell lymphomas in RA and SLE patients, whereas pSS has been linked with increased risk of mucosa-associated lymphoid tissue lymphoma. This review summarizes recent literature evaluating risk of lymphomas in arthritis patients and disease specific risk determinants. We also elaborate on the association of autoimmune arthritis with specific lymphoma variants along with genetic, environmental, and therapeutic risk factors. PMID:27429984
Raviraj; Henry, Renoy A; Rao, G Ganapathi
2017-04-01
Tuberculous meningitis is an infection of the meninges caused by Mycobacterium tuberculosis . It is one of the most common infectious diseases of the Central Nervous System (CNS) and a major health problem in developing countries like India. If there is delay in diagnosis and initiation of specific treatment, it causes significant morbidity and mortality. CSF-ADA 10 U/l is the standard cut off value that is used for differentiation between Tuberculous (TBM) and Non-Tuberculous Meningitis (non-TBM). To determine and validate a lower cut off value for CSF-ADA for diagnosing TBM in an Indian setting. This was a prospective study involving 85 cases of meningitis whose CSF were analysed and ADA estimated using an enzymatic deamination assay kit. Diagnosis of various types of meningitis was made based on specified diagnostic criteria. The comparison of mean value of CSF- ADA activity of the two types of meningitis was done using two Sample t-test. A p-value of <0.05 was considered as significant. Cut off value to differentiate between TBM and non-TBM meningitis was determined using ROC curve analysis. The CSF-ADA activity of TBM and non-TBM cases was compared. The mean CSF-ADA activity was found to be significantly higher in TBM patients (10.97±4.43; Mean±SD) than in non-TBM patients (5.09±1.53) which was statistically significant with a p-value of <0.001. A cut off value of 6.65 was calculated using ROC curve for the diagnosis of TBM which gave a sensitivity of 85.3% and a specificity of 84.3% for differentiating TBM from non-TBM. The positive predictive value was 78.3% and negative predictive value of 89.5% using the above cut off. The positive likelihood ratio was 5.44 and negative likelihood ratio of 0.17 when this lower cut off value was applied. This study has demonstrated that CSF-ADA can be used as an important diagnostic tool in early diagnosis of TBM using a cut off value of 6.65. This cut off value gave a good sensitivity and specificity in differentiating it from non-TBM.
Likelihood for transcriptions in a genetic regulatory system under asymmetric stable Lévy noise.
Wang, Hui; Cheng, Xiujun; Duan, Jinqiao; Kurths, Jürgen; Li, Xiaofan
2018-01-01
This work is devoted to investigating the evolution of concentration in a genetic regulation system, when the synthesis reaction rate is under additive and multiplicative asymmetric stable Lévy fluctuations. By focusing on the impact of skewness (i.e., non-symmetry) in the probability distributions of noise, we find that via examining the mean first exit time (MFET) and the first escape probability (FEP), the asymmetric fluctuations, interacting with nonlinearity in the system, lead to peculiar likelihood for transcription. This includes, in the additive noise case, realizing higher likelihood of transcription for larger positive skewness (i.e., asymmetry) index β, causing a stochastic bifurcation at the non-Gaussianity index value α = 1 (i.e., it is a separating point or line for the likelihood for transcription), and achieving a turning point at the threshold value β≈-0.5 (i.e., beyond which the likelihood for transcription suddenly reversed for α values). The stochastic bifurcation and turning point phenomena do not occur in the symmetric noise case (β = 0). While in the multiplicative noise case, non-Gaussianity index value α = 1 is a separating point or line for both the MFET and the FEP. We also investigate the noise enhanced stability phenomenon. Additionally, we are able to specify the regions in the whole parameter space for the asymmetric noise, in which we attain desired likelihood for transcription. We have conducted a series of numerical experiments in "regulating" the likelihood of gene transcription by tuning asymmetric stable Lévy noise indexes. This work offers insights for possible ways of achieving gene regulation in experimental research.
Skin-prick testing as a diagnostic aid for childhood asthma.
Chan, E Y; Dundas, I; Bridge, P D; Healy, M J R; McKenzie, S A
2005-06-01
Diagnosing asthma is problematic when based solely on reported symptoms. The purpose of this study was to evaluate skin-prick testing as a diagnostic aid for asthma in children. Skin-prick testing (SPT) was undertaken in children aged 2-10 years with either no history of wheeze (n = 149) or recent doctor-observed wheeze which responded to treatment with a bronchodilator, the "gold standard" (n = 164). Children with moderate or severe asthma were excluded. SPT positivity increased sharply at age 5 years in wheezers. Data were therefore divided into two age groups: 2- < 5 years (57 controls, 97 wheezers) and 5-10 years (92 controls, 67 wheezers). The sensitivity, specificity, and likelihood ratios of SPT positivity for wheeze were 32%, 89%, and 2.9, respectively, in the younger children, and 82%, 85%, and 5.5, respectively, in the older children. For a prevalence of 30% for asthma, the positive predictive values of a positive SPT were 55% and 70% for the younger and older age groups, respectively. The test characteristics of SPT for helping diagnose asthma in schoolchildren are good. The prevalence of wheeze in preschool children is high, and so SPT should be helpful even in this group. We suggest that clinicians consider skin-prick testing as a diagnostic aid for asthma. Copyright 2005 Wiley-Liss, Inc.
Does the presence and mix of destinations influence walking and physical activity?
King, Tania Louise; Bentley, Rebecca Jodie; Thornton, Lukar Ezra; Kavanagh, Anne Marie
2015-09-17
Local destinations have previously been shown to be associated with higher levels of both physical activity and walking, but little is known about how specific destinations are related to activity. This study examined associations between types and mix of destinations and both walking frequency and physical activity. The sample consisted of 2349 residents of 50 urban areas in metropolitan Melbourne, Australia. Using geographic information systems, seven types of destinations were examined within three network buffers (400 meters (m), 800 m and 1200 m) of respondents' homes. Multilevel logistic regression was used to estimate effects of each destination type separately, as well as destination mix (variety) on: 1) likelihood of walking for at least 10 min ≥ 4/week; 2) likelihood of being sufficiently physically active. All models were adjusted for potential confounders. All destination types were positively associated with walking frequency, and physical activity sufficiency at 1200 m. For the 800 m buffer: all destinations except transport stops and sports facilities were significantly associated with physical activity, while all except sports facilities were associated with walking frequency; at 400 m, café/takeaway food stores and transport stops were associated with walking frequency and physical activity sufficiency, and sports facilities were also associated with walking frequency. Strongest associations for both outcomes were observed for community resources and small food stores at both 800 m and 1200 m. For all buffer distances: greater mix was associated with greater walking frequency. Inclusion of walking in physical activity models led to attenuation of associations. The results of this analysis indicate that there is an association between destinations and both walking frequency and physical activity sufficiency, and that this relationship varies by destination type. It is also clear that greater mix of destinations positively predicts walking frequency and physical activity sufficiency.
Misuse of ultrasound for palpable undescended testis by primary care providers: A prospective study
Wong, Nathan C.; Bansal, Rahul K.; Lorenzo, Armando J.; DeMaria, Jorge; Braga, Luis H.
2015-01-01
Introduction: Although previous evidence has shown that ultrasound is unreliable to diagnose undescended testis, many primary care providers (PCP) continue to misuse it. We assessed the performance of ultrasound as a diagnostic tool for palpable undescended testis, as well as the diagnostic agreement between PCP and pediatric urologists. Methods: We performed a prospective observational cohort study between 2011 and 2013 for consecutive boys referred with a diagnosis of undescended testis to our tertiary pediatric hospital. Patients referred without an ultrasound and those with non-palpable testes were excluded. Data on referring diagnosis, pediatric urology examination and ultrasound reports were analyzed. Results: Our study consisted of 339 boys. Of these, patients without an ultrasound (n = 132) and those with non-palpable testes (n = 38) were excluded. In the end, there were 169 pateints in this study. Ultrasound was performed in 50% of referred boys showing 256 undescended testis. The mean age at time of referral was 45 months. When ultrasound was compared to physical examination by the pediatric urologist, agreement was only 34%. The performance of ultrasound for palpable undescended testis was: sensitivity = 100%; specificity = 16%; positive predictive value = 34%; negative predictive value = 100%; positive likelihood ratio = 1.2; and negative likelihood ratio = 0. Diagnosis of undescended testis by PCP was confirmed by physical examination in 30% of cases, with 70% re-diagnosed with normal or retractile testes. Conclusion: Ultrasound performed poorly to assess for palpable undescended testis in boys and should not be used. Although the study has important limitations, there is an increasing need for education and evidence-based guidelines for PCP in the management of undescended testis. PMID:26788226
Awais, Muhammad; Rehman, Abdul; Zaman, Maseeh Uz; Nadeem, Naila
2015-01-01
Performing micturiting cystourethrography (MCUG) in young children with recurrent urinary tract infections is controversial with discrepancy among the major guidelines. Previous studies have shown that a normal dimercaptosuccinic acid (DMSA) scintigraphy may avoid the need of performing MCUG for detecting vesicoureteric reflux in children with first febrile urinary tract infection. However, the role of DMSA for ruling out vesicoureteric reflux in children with recurrent urinary tract infections has not been studied. Approval from institutional ethical review committee was sought and the requirement of informed consent was waived. A total of 50 children under the age of 10 years with recurrent urinary tract infections underwent MCUG scan within 3 months of DMSA scan from January 2011 to September 2012 at our institution. Diagnosis of recurrent urinary tract infections and grading of vesicoureteric reflux was according to previously established standards. Abnormalities on DMSA scan - scarring, hydronephrosis and reduced differential renal function - were compared with presence of vesicoureteric reflux on MCUG. High-grade vesicoureteric reflux was noted on MCUG in 22 (44%) cases. The findings on DMSA included hydronephrosis and scarring in 25 (50%) and 25 (50%) cases, respectively. Abnormalities on DMSA scan for detecting the presence of high-grade vesicoureteric reflux on MCUG examination had sensitivity, specificity, positive and negative predictive values of 95.45%, 35.71%, 53.85% and 90.91%, respectively. The positive and negative likelihood ratios were 1.48 and 0.13 respectively. DMSA scan had high overall sensitivity and negative predictive value with a low negative likelihood ratio for ruling out high-grade vesicoureteric reflux on MCUG, which may obviate the need of invasive MCUG along with its associated drawbacks.
Wang, Bo; Lin, Yin; Pan, Fu-shun; Yao, Chen; Zheng, Zi-Yu; Cai, Dan; Xu, Xiang-dong
2013-01-01
Wells score has been validated for estimation of pretest probability in patients with suspected deep vein thrombosis (DVT). In clinical practice, many clinicians prefer to use empirical estimation rather than Wells score. However, which method is better to increase the accuracy of clinical evaluation is not well understood. Our present study compared empirical estimation of pretest probability with the Wells score to investigate the efficiency of empirical estimation in the diagnostic process of DVT. Five hundred and fifty-five patients were enrolled in this study. One hundred and fifty patients were assigned to examine the interobserver agreement for Wells score between emergency and vascular clinicians. The other 405 patients were assigned to evaluate the pretest probability of DVT on the basis of the empirical estimation and Wells score, respectively, and plasma D-dimer levels were then determined in the low-risk patients. All patients underwent venous duplex scans and had a 45-day follow up. Weighted Cohen's κ value for interobserver agreement between emergency and vascular clinicians of the Wells score was 0.836. Compared with Wells score evaluation, empirical assessment increased the sensitivity, specificity, Youden's index, positive likelihood ratio, and positive and negative predictive values, but decreased negative likelihood ratio. In addition, the appropriate D-dimer cutoff value based on Wells score was 175 μg/l and 108 patients were excluded. Empirical assessment increased the appropriate D-dimer cutoff point to 225 μg/l and 162 patients were ruled out. Our findings indicated that empirical estimation not only improves D-dimer assay efficiency for exclusion of DVT but also increases clinical judgement accuracy in the diagnosis of DVT.
McMahon, Michael J; Sheikh, Karen L; Andrada, Teotimo F; Holley, Aaron B
2017-12-01
The STOPBANG questionnaire is used to predict the presence of obstructive sleep apnea (OSA). We sought to assess the performance of the STOPBANG questionnaire in younger, thinner patients referred to a sleep medicine clinic. We applied the STOPBANG questionnaire to patients referred for level I polysomnography (PSG) at our sleep center. We calculated likelihood ratios and area under the receiver operator characteristic (AUROC) curve and performed sensitivity analyses. We performed our analysis on 338 patients referred for PSG. Only 17.2% (n = 58) were above age 50 years, and 30.5 and 6.8% had a BMI above 30 and 35 years, respectively. The mean apnea-hypopnea index (AHI) was 12.9 ± 16.4 and 63.9% had an AHI ≥5. The STOPBANG (threshold ≥3) identified 83.1% of patients as high risk for an AHI ≥5, and sensitivity, specificity, positive (PPV), and negative predictive values (NPV) were 83.8, 18.0, 64.4, and 38.0%, respectively. Positive and negative likelihood ratios were poor at 1.02-1.11 and 0.55-0.90, respectively, across AHI thresholds (AHI ≥5, AHI ≥15 and AHI ≥30), and AUROCs were 0.52 (AHI ≥5) and 0.56 (AHI ≥15). Sensitivity analyses adjusting for insomnia, combat deployment, traumatic brain injury, post-traumatic stress disorder, clinically significant OSA (ESS >10 and/or co-morbid disease), and obesity did not significantly alter STOPBANG performance. In a younger, thinner population with predominantly mild-to-moderate OSA, the STOPBANG Score does not accurately predict the presence of obstructive sleep apnea.
The utility of focused abdominal ultrasound in blunt abdominal trauma: a reappraisal.
Helling, Thomas S; Wilson, Jennifer; Augustosky, Kim
2007-12-01
Focused assessment with sonography for trauma (FAST) has become commonplace in the management of blunt abdominal trauma. However, newer computed tomography (CT) scanners have decreased imaging time for trauma patients and provide more detailed examination of abdominal contents. It was the aim of the current study to evaluate practice patterns of FAST and abdominal CT in blunt trauma victims. This was a retrospective study of all blunt trauma patients (N = 299) who received at least 1 FAST examination in the emergency department by surgeons and were admitted. Patients were tracked for subsequent CT scanning, disposition from the emergency department, any operative findings, and survival. Twenty-one of 299 patients (7%) had a positive FAST. There were 7 deaths and 14 patients were taken directly to the operating room (OR) for control of abdominal bleeding. Thirty-one of 299 (10%) had equivocal FAST. There were 4 deaths and 8 patients were taken to the OR for control of abdominal bleeding. A total of 247 of the 299 patients had a negative FAST. CT scans were performed in 193: 15 showed a visceral injury. There were 13 deaths and 29 patients were taken to the OR (4 for bleeding). Patients with a positive FAST had a higher mortality than FAST-negative patients (P < .001) and greater likelihood for operation (P < .001). Those with equivocal FAST had a greater likelihood for operation than FAST-negative patients (P < .05). FAST examinations can identify patients at risk for hemorrhage and in whom operation may be needed and, therefore, can guide mobilization of hospital resources. FAST-negative patients can be managed expectantly, using more specific imaging techniques.
Rodríguez-Cortés, Alhelí; Ojeda, Ana; Todolí, Felicitat; Alberola, Jordi
2013-01-31
Leishmania infantum (syn. Leishmania chagasi) is the etiological agent of a widespread serious zoonotic disease that affects both humans and dogs. Prevalence and incidence of the canine infection are important parameters to determine the risk and the ways to control this reemergent zoonosis. Unfortunately, there is not a gold standard test for Leishmania infection. Our aim was to assess the operative validity of commercial tests used to detect antibodies to Leishmania in serum samples from experimental infections. Three ELISA tests (LEISCAN(®) Leishmania ELISA Test, INGEZIM(®) LEISHMANIA, and INGEZIM(®) LEISHMANIA VET), three immunochromatographic tests (INGEZIM(®) LEISHMACROM, SNAP(®) Leishmania, and WITNESS(®) Leishmania), and one IFAT were evaluated. LEISCAN(®) Leishmania ELISA test achieved the highest sensitivity and accuracy (both 0.98). Specificity was 1 for all tests except for IFAT. All tests but IFAT obtained a positive predictive value of 1, while the maximum negative predictive value was achieved by LEISCAN(®) Leishmania ELISA Test (0.93). The best positive likelihood ratio was obtained by INGEZIM(®) LEISHMANIA VET (30.26), while the best negative likelihood ratio was obtained by LEISCAN(®) Leishmania ELISA Test (0.02). The highest diagnostic odds ratio was achieved by LEISCAN(®) Leishmania ELISA Test (729.00). The largest area under the ROC curve was obtained by LEISCAN(®) Leishmania ELISA Test (0.981). Quantitative ELISA based tests performmed better than qualitative tests ("Rapid Tests"), and the test best suited to detect Leishmania in infected dogs and to provide clinically useful information was LEISCAN(®) Leishmania ELISA Test. This and other results point also to the need of revising the status of IFAT as a gold standard for the diagnosis of leishmaniasis. Copyright © 2012 Elsevier B.V. All rights reserved.
Basirat, Vahid; Azizi, Zahra; Javid Anbardan, Sanam; Taghizadeh Asl, Mina; Farbod, Yasaman; Teimouri, Azam; Ebrahimi Daryani, Nasser
2016-01-01
INTRODUCTION Due to limitation of colonoscopy in assessing the entire bowel and patients’ intolerance in inflammatory bowel disease (IBD), in the current study, we aimed to prospectively compare the accuracy of 99mTc(V)-dimercaptosuccinic acid (DMSA) and fecal calprotectin with ileocolonoscopy as new methods for localizing inflammations. METHODS Current prospective study conducted between 2012 and 2014 on 30 patients with IBD attending Gastroenterology Clinic of Tehran University of Medical Sciences. Fecal calprotectin and disease activity were measured for all participants and all of them underwent 99mTc (V)-DMSA scintigraphy and colonoscopy. The accuracy of 99mTc (V)-DMSA scintigraphy and calprotectin in localizing bowel lesions were calculated. RESULTS A total of 22 patients with ulcerative colitis (UC) and 8 patients with Crohn’s disease (CD) were evaluated in our study. Sensitivity, positive likelihood ratio (PLR), and positive predictive value (PPV) of scintigraphy and calprotectin over colonoscopy in localization of UC lesions were 86.36%, 0.86%, 100.00% and 90.91%, 0.91, and 100.00%, respectively. Meanwhile, it showed 66.67% sensitivity and 81.25% specificity with PLR=3.56, negative likelihood ratio (NLR)=0.41, PPV=84.21%, and negative predictive value (NPV)= 61.90% in localizing lesions in patients with CD. The calprotectin level had sensitivity, PLR, and PPV of 90.00%, 0.90, and 100.00% in detecting active disease over colonoscopy, respectively. CONCLUSION The 99mTc (V)-DMSA scintigraphy would be an accurate method for detecting active inflammation in follow-up of patients with IBD and assessing response to treatment as a non-invasive and complementary method beside colonoscopy for more accurate diagnosis of CD or UC. PMID:27698971
Nguyen, Minh Vu Chuong; Baillet, Athan; Romand, Xavier; Trocmé, Candice; Courtier, Anaïs; Marotte, Hubert; Thomas, Thierry; Soubrier, Martin; Miossec, Pierre; Tébib, Jacques; Grange, Laurent; Toussaint, Bertrand; Lequerré, Thierry; Vittecoq, Olivier; Gaudin, Philippe
2018-06-06
Tumour necrosis factor-alpha inhibitors (TNFi) are effective treatments for Rheumatoid Arthritis (RA). Responses to treatment are barely predictable. As these treatments are costly and may induce a number of side effects, we aimed at identifying a panel of protein biomarkers that could be used to predict clinical response to TNFi for RA patients. Baseline blood levels of C-reactive protein, platelet factor 4, apolipoprotein A1, prealbumin, α1-antitrypsin, haptoglobin, S100A8/A9 and S100A12 proteins in bDMARD naive patients at the time of TNFi treatment initiation were assessed in a multicentric prospective French cohort. Patients fulfilling good EULAR response at 6 months were considered as responders. Logistic regression was used to determine best biomarker set that could predict good clinical response to TNFi. A combination of biomarkers (prealbumin, platelet factor 4 and S100A12) was identified and could predict response to TNFi in RA with sensitivity of 78%, specificity of 77%, positive predictive values (PPV) of 72%, negative predictive values (NPV) of 82%, positive likelihood ratio (LR+) of 3.35 and negative likelihood ratio (LR-) of 0.28. Lower levels of prealbumin and S100A12 and higher level of platelet factor 4 than the determined cutoff at baseline in RA patients are good predictors for response to TNFi treatment globally as well as to Infliximab, Etanercept and Adalimumab individually. A multivariate model combining 3 biomarkers (prealbumin, platelet factor 4 and S100A12) accurately predicted response of RA patients to TNFi and has potential in a daily practice personalized treatment. Copyright © 2018. Published by Elsevier Masson SAS.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hogden, J.
The goal of the proposed research is to test a statistical model of speech recognition that incorporates the knowledge that speech is produced by relatively slow motions of the tongue, lips, and other speech articulators. This model is called Maximum Likelihood Continuity Mapping (Malcom). Many speech researchers believe that by using constraints imposed by articulator motions, we can improve or replace the current hidden Markov model based speech recognition algorithms. Unfortunately, previous efforts to incorporate information about articulation into speech recognition algorithms have suffered because (1) slight inaccuracies in our knowledge or the formulation of our knowledge about articulation maymore » decrease recognition performance, (2) small changes in the assumptions underlying models of speech production can lead to large changes in the speech derived from the models, and (3) collecting measurements of human articulator positions in sufficient quantity for training a speech recognition algorithm is still impractical. The most interesting (and in fact, unique) quality of Malcom is that, even though Malcom makes use of a mapping between acoustics and articulation, Malcom can be trained to recognize speech using only acoustic data. By learning the mapping between acoustics and articulation using only acoustic data, Malcom avoids the difficulties involved in collecting articulator position measurements and does not require an articulatory synthesizer model to estimate the mapping between vocal tract shapes and speech acoustics. Preliminary experiments that demonstrate that Malcom can learn the mapping between acoustics and articulation are discussed. Potential applications of Malcom aside from speech recognition are also discussed. Finally, specific deliverables resulting from the proposed research are described.« less
Validation of Thwaites Index for diagnosing tuberculous meningitis in a Colombian population.
Saavedra, Juan Sebastián; Urrego, Sebastián; Toro, María Eugenia; Uribe, Carlos Santiago; García, Jenny; Hernández, Olga; Arango, Juan Carlos; Pérez, Ángela Beatriz; Franco, Andrés; Vélez, Isabel Cristina; Del Corral, Helena
2016-11-15
To determine the diagnostic accuracy of Thwaites Index (TI) in a Colombian population to distinguish meningeal tuberculosis (MTB) from bacterial meningitis (BM) and from non-tuberculous meningitis. Exploratory analyses were conducted to assess the TI's validity for patients with human immunodeficiency virus (HIV) and children above six-years-old. The study included 527 patients, the TI was calculated and results compared with those of a reference standard established by expert neurologists. Sensitivity, specificity, area under the curve of receiver-operator characteristics (AUC-ROC) and likelihood ratios were calculated. The AUC-ROC to distinguish MTB from non-tuberculous meningitis was 0.72 (95% CI: 0.67-0.77) for HIV negative adults. AUC-ROC was 0.62 (95% CI: 0.50-0.74) for HIV positive adults and 0.83 (95% CI: 0.68-0.97) for children. For distinguishing MTB from BM the AUC-ROC was 0.78 (95% CI: 0.73-0.83); furthermore, the AUC-ROC was 0.57 (95% CI: 0.31-0.83) for HIV positive adults and 0.86 (95% CI: 0.73-0.99) for children. The TI was sensitive but not specific when used to distinguish MTB from BM in HIV negative adults. In HIV positive adults the index had low diagnostic accuracy. Moreover, the TI showed discrimination capability for children over 6years; however, research with larger samples is required in these. Copyright © 2016 Elsevier B.V. All rights reserved.
Heritability of mandibular cephalometric variables in twins with completed craniofacial growth.
Šidlauskas, Mantas; Šalomskienė, Loreta; Andriuškevičiūtė, Irena; Šidlauskienė, Monika; Labanauskas, Žygimantas; Vasiliauskas, Arūnas; Kupčinskas, Limas; Juzėnas, Simonas; Šidlauskas, Antanas
2016-10-01
To determine genetic and environmental impact on mandibular morphology using lateral cephalometric analysis of twins with completed mandibular growth and deoxyribonucleic acid (DNA) based zygosity determination. The 39 cephalometric variables of 141 same gender adult pair of twins were analysed. Zygosity was determined using 15 specific DNA markers and cervical vertebral maturation method was used to assess completion of the mandibular growth. A genetic analysis was performed using maximum likelihood genetic structural equation modelling (GSEM). The genetic heritability estimates of angular variables describing horizontal mandibular position in relationship to cranial base and maxilla were considerably higher than in those describing vertical position. The mandibular skeletal cephalometric variables also showed high heritability estimates with angular measurements being considerably higher than linear ones. Results of this study indicate that the angular measurements representing mandibular skeletal morphology (mandibular form) have greater genetic determination than the linear measurements (mandibular size). The shape and sagittal position of the mandible is under stronger genetic control, than is its size and vertical relationship to cranial base. © The Author 2015. Published by Oxford University Press on behalf of the European Orthodontic Society. All rights reserved. For permissions, please email: journals.permissions@oup.com.
Gaussian Decomposition of Laser Altimeter Waveforms
NASA Technical Reports Server (NTRS)
Hofton, Michelle A.; Minster, J. Bernard; Blair, J. Bryan
1999-01-01
We develop a method to decompose a laser altimeter return waveform into its Gaussian components assuming that the position of each Gaussian within the waveform can be used to calculate the mean elevation of a specific reflecting surface within the laser footprint. We estimate the number of Gaussian components from the number of inflection points of a smoothed copy of the laser waveform, and obtain initial estimates of the Gaussian half-widths and positions from the positions of its consecutive inflection points. Initial amplitude estimates are obtained using a non-negative least-squares method. To reduce the likelihood of fitting the background noise within the waveform and to minimize the number of Gaussians needed in the approximation, we rank the "importance" of each Gaussian in the decomposition using its initial half-width and amplitude estimates. The initial parameter estimates of all Gaussians ranked "important" are optimized using the Levenburg-Marquardt method. If the sum of the Gaussians does not approximate the return waveform to a prescribed accuracy, then additional Gaussians are included in the optimization procedure. The Gaussian decomposition method is demonstrated on data collected by the airborne Laser Vegetation Imaging Sensor (LVIS) in October 1997 over the Sequoia National Forest, California.
Asimos, Andrew W; Ward, Shana; Brice, Jane H; Rosamond, Wayne D; Goldstein, Larry B; Studnek, Jonathan
2014-11-01
Emergency medical services (EMS) protocols, which route patients with suspected stroke to stroke centers, rely on the use of accurate stroke screening criteria. Our goal is to conduct a statewide EMS agency evaluation of the accuracies of the Cincinnati Prehospital Stroke Scale (CPSS) and the Los Angeles Prehospital Stroke Screen (LAPSS) for identifying acute stroke patients. We conducted a retrospective study in North Carolina by linking a statewide EMS database to a hospital database, using validated deterministic matching. We compared EMS CPSS or LAPSS results (positive or negative) to the emergency department diagnosis International Classification of Diseases, Ninth Revision codes. We calculated sensitivity, specificity, and positive and negative likelihood ratios for the EMS diagnosis of stroke, using each screening tool. We included 1,217 CPSS patients and 1,225 LAPSS patients evaluated by 117 EMS agencies from 94 North Carolina counties. Most EMS agencies contributing data had high annual patient volumes and were governmental agencies with nonvolunteer, emergency medical technician-paramedic service level providers. The CPSS had a sensitivity of 80% (95% confidence interval [CI] 77% to 83%) versus 74% (95% CI 71% to 77%) for the LAPSS. Each had a specificity of 48% (CPSS 95% CI 44% to 52%; LAPSS 95% CI 43% to 53%). The CPSS and LAPSS had similar test characteristics, with each having only limited specificity. Development of stroke screening scales that optimize both sensitivity and specificity is required if these are to be used to determine transport diversion to acute stroke centers. Copyright © 2014. Published by Elsevier Inc.
Meta-analysis: accuracy of rapid tests for malaria in travelers returning from endemic areas.
Marx, Arthur; Pewsner, Daniel; Egger, Matthias; Nüesch, Reto; Bucher, Heiner C; Genton, Blaise; Hatz, Christoph; Jüni, Peter
2005-05-17
Microscopic diagnosis of malaria is unreliable outside specialized centers. Rapid tests have become available in recent years, but their accuracy has not been assessed systematically. To determine the accuracy of rapid diagnostic tests for ruling out malaria in nonimmune travelers returning from malaria-endemic areas. The authors searched MEDLINE, EMBASE, CAB Health, and CINAHL (1988 to September 2004); hand-searched conference proceedings; checked reference lists; and contacted experts and manufacturers. Diagnostic accuracy studies in nonimmune individuals with suspected malaria were included if they compared rapid tests with expert microscopic examination or polymerase chain reaction tests. Data on study and patient characteristics and results were extracted in duplicate. The main outcome was the likelihood ratio for a negative test result (negative likelihood ratio) for Plasmodium falciparum malaria. Likelihood ratios were combined by using random-effects meta-analysis, stratified by the antigen targeted (histidine-rich protein-2 [HRP-2] or parasite lactate dehydrogenase [LDH]) and by test generation. Nomograms of post-test probabilities were constructed. The authors included 21 studies and 5747 individuals. For P. falciparum, HRP-2-based tests were more accurate than parasite LDH-based tests: Negative likelihood ratios were 0.08 and 0.13, respectively (P = 0.019 for difference). Three-band HRP-2 tests had similar negative likelihood ratios but higher positive likelihood ratios compared with 2-band tests (34.7 vs. 98.5; P = 0.003). For P. vivax, negative likelihood ratios tended to be closer to 1.0 for HRP-2-based tests than for parasite LDH-based tests (0.24 vs. 0.13; P = 0.22), but analyses were based on a few heterogeneous studies. Negative likelihood ratios for the diagnosis of P. malariae or P. ovale were close to 1.0 for both types of tests. In febrile travelers returning from sub-Saharan Africa, the typical probability of P. falciparum malaria is estimated at 1.1% (95% CI, 0.6% to 1.9%) after a negative 3-band HRP-2 test result and 97% (CI, 92% to 99%) after a positive test result. Few studies evaluated 3-band HRP-2 tests. The evidence is also limited for species other than P. falciparum because of the few available studies and their more heterogeneous results. Further studies are needed to determine whether the use of rapid diagnostic tests improves outcomes in returning travelers with suspected malaria. Rapid malaria tests may be a useful diagnostic adjunct to microscopy in centers without major expertise in tropical medicine. Initial decisions on treatment initiation and choice of antimalarial drugs can be based on travel history and post-test probabilities after rapid testing. Expert microscopy is still required for species identification and confirmation.
The complexity of selection at the major primate β-defensin locus
Semple, Colin AM; Maxwell, Alison; Gautier, Philippe; Kilanowski, Fiona M; Eastwood, Hayden; Barran, Perdita E; Dorin, Julia R
2005-01-01
Background We have examined the evolution of the genes at the major human β-defensin locus and the orthologous loci in a range of other primates and mouse. For the first time these data allow us to examine selective episodes in the more recent evolutionary history of this locus as well as the ancient past. We have used a combination of maximum likelihood based tests and a maximum parsimony based sliding window approach to give a detailed view of the varying modes of selection operating at this locus. Results We provide evidence for strong positive selection soon after the duplication of these genes within an ancestral mammalian genome. Consequently variable selective pressures have acted on β-defensin genes in different evolutionary lineages, with episodes both of negative, and more rarely positive selection, during the divergence of primates. Positive selection appears to have been more common in the rodent lineage, accompanying the birth of novel, rodent-specific β-defensin genes. These observations allow a fuller understanding of the evolution of mammalian innate immunity. In both the rodent and primate lineages, sites in the second exon have been subject to positive selection and by implication are important in functional diversity. A small number of sites in the mature human peptides were found to have undergone repeated episodes of selection in different primate lineages. Particular sites were consistently implicated by multiple methods at positions throughout the mature peptides. These sites are clustered at positions predicted to be important for the specificity of the antimicrobial or chemoattractant properties of β-defensins. Surprisingly, sites within the prepropeptide region were also implicated as being subject to significant positive selection, suggesting previously unappreciated functional significance for this region. Conclusions Identification of these putatively functional sites has important implications for our understanding of β-defensin function and for novel antibiotic design. PMID:15904491
Non-Culture Diagnostics for Invasive Candidiasis: Promise and Unintended Consequences
Clancy, Cornelius J.; Nguyen, M. Hong
2018-01-01
Blood cultures are positive for Candida species in < 50% and < 20% of hematogenously disseminated and intra-abdominal candidiasis, respectively. Non-culture tests such as mannan, anti-mannan antibody, Candida albicans germ tube antibody (CAGTA), 1,3-β-d-glucan (BDG), the T2Candida nanodiagnostic panel, and polymerase chain reaction (PCR) are available for clinical use, but their roles in patient care are uncertain. Sensitivity/specificity of combined mannan/anti-mannan, BDG, T2Candida and PCR for candidemia are ~80%/80%, ~80%/80%, ~90%/98%, and ~90%/90%, respectively. Limited data for intra-abdominal candidiasis suggest CAGTA, BDG sensitivity/specificity of ~65%/75% and PCR sensitivity of ~85–90%. PCR specificity has varied widely for intra-abdominal candidiasis (33–97%), and T2Candida data are lacking. Tests will be useful if restricted to cases in which positive and negative predictive values (PPVs, NPVs) differ in a clinically meaningful way from the pre-test likelihood of invasive candidiasis. In some patients, PPVs are sufficient to justify antifungal treatment, even if blood cultures are negative. In most patients, NPVs of each test are excellent, which may support decisions to withhold antifungal therapy. If test results are not interpreted judiciously, non-culture diagnostics may have unintended consequences for stewardship and infection prevention programs. In particular, discrepant non-culture test-positive/culture-negative results may promote inappropriate antifungal treatment of patients who are unlikely to have candidiasis, and lead to spurious reporting of hospital-acquired infections. In conclusion, non-culture Candida diagnostics have potential to advance patient care, but this promise will be realized only if users understand tests’ strengths and limitations, and plan proactively for how best to employ them at their hospitals. PMID:29463043
Privacy Risks from Genomic Data-Sharing Beacons
Shringarpure, Suyash S.; Bustamante, Carlos D.
2015-01-01
The human genetics community needs robust protocols that enable secure sharing of genomic data from participants in genetic research. Beacons are web servers that answer allele-presence queries—such as “Do you have a genome that has a specific nucleotide (e.g., A) at a specific genomic position (e.g., position 11,272 on chromosome 1)?”—with either “yes” or “no.” Here, we show that individuals in a beacon are susceptible to re-identification even if the only data shared include presence or absence information about alleles in a beacon. Specifically, we propose a likelihood-ratio test of whether a given individual is present in a given genetic beacon. Our test is not dependent on allele frequencies and is the most powerful test for a specified false-positive rate. Through simulations, we showed that in a beacon with 1,000 individuals, re-identification is possible with just 5,000 queries. Relatives can also be identified in the beacon. Re-identification is possible even in the presence of sequencing errors and variant-calling differences. In a beacon constructed with 65 European individuals from the 1000 Genomes Project, we demonstrated that it is possible to detect membership in the beacon with just 250 SNPs. With just 1,000 SNP queries, we were able to detect the presence of an individual genome from the Personal Genome Project in an existing beacon. Our results show that beacons can disclose membership and implied phenotypic information about participants and do not protect privacy a priori. We discuss risk mitigation through policies and standards such as not allowing anonymous pings of genetic beacons and requiring minimum beacon sizes. PMID:26522470
Privacy Risks from Genomic Data-Sharing Beacons.
Shringarpure, Suyash S; Bustamante, Carlos D
2015-11-05
The human genetics community needs robust protocols that enable secure sharing of genomic data from participants in genetic research. Beacons are web servers that answer allele-presence queries--such as "Do you have a genome that has a specific nucleotide (e.g., A) at a specific genomic position (e.g., position 11,272 on chromosome 1)?"--with either "yes" or "no." Here, we show that individuals in a beacon are susceptible to re-identification even if the only data shared include presence or absence information about alleles in a beacon. Specifically, we propose a likelihood-ratio test of whether a given individual is present in a given genetic beacon. Our test is not dependent on allele frequencies and is the most powerful test for a specified false-positive rate. Through simulations, we showed that in a beacon with 1,000 individuals, re-identification is possible with just 5,000 queries. Relatives can also be identified in the beacon. Re-identification is possible even in the presence of sequencing errors and variant-calling differences. In a beacon constructed with 65 European individuals from the 1000 Genomes Project, we demonstrated that it is possible to detect membership in the beacon with just 250 SNPs. With just 1,000 SNP queries, we were able to detect the presence of an individual genome from the Personal Genome Project in an existing beacon. Our results show that beacons can disclose membership and implied phenotypic information about participants and do not protect privacy a priori. We discuss risk mitigation through policies and standards such as not allowing anonymous pings of genetic beacons and requiring minimum beacon sizes. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.
Diagnosis of obstructive sleep apnea using pulse oximeter derived photoplethysmographic signals.
Romem, Ayal; Romem, Anat; Koldobskiy, Dafna; Scharf, Steven M
2014-03-15
Increasing awareness of the high prevalence of obstructive sleep apnea (OSA) and its impact on health in conjunction with high cost, inconvenience, and short supply of in-lab polysomnography (PSG) has led to the development of more convenient, affordable, and accessible diagnostic devices. We evaluated the reliability and accuracy of a single-channel (finger pulse-oximetry) photoplethysmography (PPG)-based device for detection of OSA (Morpheus Ox). Among a cohort of 73 patients referred for in-laboratory evaluation of OSA, 65 were simultaneously monitored with the PPG based device while undergoing PSG. Among these, 19 had significant cardiopulmonary comorbidities. Using the PSG as the "gold standard," the sensitivity, specificity, negative predictive value (NPV), positive predictive value (PPV), as well as the positive likelihood ratio (+LR) for an apnea hypopnea index (AHI)PSG > 5/h and AHIPSG > 15/h were calculated for the PPG. Valid results were available for 65 subjects. Mean age: 52.1 ± 14.2, Male: 52%, and BMI: 36.3 ± 9.7 kg/m(2). Positive correlation was found between PPG-derived and PSG-derived AHI (r = 0.81, p < 0.001). For AHIPSG > 5/h, sensitivity was 80%, specificity 86%, PPV 93%, NPV 68%, and +LR was 5.9. For AHIPSG > 15/h, sensitivity was 70%, specificity 91%, PPV 80%, NPV 85%, and +LR was 7.83. The corresponding areas under the receiver operator curves were 0.91 and 0.9. PPG-derived data compare well with simultaneous in-lab PSG in the diagnosis of suspected OSA among patients with and without cardiopulmonary comorbidities. Romem A; Romem A; Koldobskiy D; Scharf SM. Diagnosis of obstructive sleep apnea using pulse oximeter derived photoplethysmographic signals.
Murdock, Andrew G
2008-05-01
Closely related outgroups are optimal for rooting phylogenetic trees; however, such ideal outgroups are not always available. A phylogeny of the marattioid ferns (Marattiaceae), an ancient lineage with no close relatives, was reconstructed using nucleotide sequences of multiple chloroplast regions (rps4 + rps4-trnS spacer, trnS-trnG spacer + trnG intron, rbcL, atpB), from 88 collections, selected to cover the broadest possible range of morphologies and geographic distributions within the extant taxa. Because marattioid ferns are phylogenetically isolated from other lineages, and internal branches are relatively short, rooting was problematic. Root placement was strongly affected by long-branch attraction under maximum parsimony and by model choice under maximum likelihood. A multifaceted approach to rooting was employed to isolate the sources of bias and produce a consensus root position. In a statistical comparison of all possible root positions with three different outgroups, most root positions were not significantly less optimal than the maximum likelihood root position, including the consensus root position. This phylogeny has several important taxonomic implications for marattioid ferns: Marattia in the broad sense is paraphyletic; the Hawaiian endemic Marattia douglasii is most closely related to tropical American taxa; and Angiopteris is monophyletic only if Archangiopteris and Macroglossum are included.
Barwick, R S; Mohammed, H O; White, M E; Bryant, R B
2003-03-01
A study was conducted to identify factors associated with the likelihood of detecting Giardia spp. and Cryptosporidium spp. in the soil of dairy farms in a watershed area. A total of 37 farms were visited, and 782 soil samples were collected from targeted areas on these farms. The samples were analyzed for the presence of Cryptosporidium spp. oocysts, Giardia spp. cysts, percent moisture content, and pH. Logistic regression analysis was used to identify risk factors associated with the likelihood of the presence of these organisms. The use of the land at the sampling site was associated with the likelihood of environmental contamination with Cryptosporidium spp. Barn cleaner equipment area and agricultural fields were associated with increased likelihood of environmental contamination with Cryptosporidium spp. The risk of environmental contamination decreased with the pH of the soil and with the score of the potential likelihood of Cryptosporidium spp. The size of the sampling site, as determined by the sampling design, in square feet, was associated nonlinearly with the risk of detecting Cryptosporidium spp. The likelihood of the Giardia cyst in the soil increased with the prevalence of Giardia spp. in animals (i.e., 18 to 39%). As the size of the farm increased, there was decreased risk of Giardia spp. in the soil, and sampling sites which were covered with brush or bare soil showed a decrease in likelihood of detecting Giardia spp. when compared to land which had managed grass. The number of cattle on the farm less than 6 mo of age was negatively associated with the risk of detecting Giardia spp. in the soil, and the percent moisture content was positively associated with the risk of detecting Giardia spp. Our study showed that these two protozoan exist in dairy farm soil at different rates, and this risk could be modified by manipulating the pH of the soil.
Thought-action fusion across anxiety disorder diagnoses: Specificity and treatment effects
Thompson-Hollands, Johanna; Farchione, Todd J.; Barlow, David H.
2013-01-01
Thought-action fusion (TAF) is a cognitive error that has been frequently investigated within the context of obsessive-compulsive disorder (OCD). However, evidence suggests that this error may also be present in disorders other than OCD, indicating that TAF is related to higher-order factors rather than a specific diagnosis. We explored TAF in a sample of patients with mixed diagnoses undergoing treatment with a transdiagnostic CBT protocol. Elevated TAF levels at baseline were not specific to patients with OCD. However, the presence of any generalized anxiety disorder (GAD) diagnosis was unexpectedly the strongest predictor of likelihood TAF. Likelihood TAF, a particular component of TAF, was reduced after transdiagnostic treatment, and this reduction was not affected by the presence of a GAD diagnosis. Results indicate that TAF is responsive to treatment and should be assessed and, perhaps, treated in disorders beyond OCD. PMID:23595095
Thought-action fusion across anxiety disorder diagnoses: specificity and treatment effects.
Thompson-Hollands, Johanna; Farchione, Todd J; Barlow, David H
2013-05-01
Thought-action fusion (TAF) is a cognitive error that has been frequently investigated within the context of obsessive-compulsive disorder (OCD). However, evidence suggests that this error may also be present in disorders other than OCD, indicating that TAF is related to higher order factors rather than a specific diagnosis. We explored TAF in a sample of patients with mixed diagnoses undergoing treatment with a transdiagnostic CBT protocol. Elevated TAF levels at baseline were not specific to patients with OCD. However, the presence of any generalized anxiety disorder (GAD) diagnosis was unexpectedly the strongest predictor of likelihood TAF. Likelihood TAF, a particular component of TAF, was reduced after transdiagnostic treatment, and this reduction was not affected by the presence of a GAD diagnosis. Results indicate that TAF is responsive to treatment and should be assessed and, perhaps, treated in disorders beyond OCD.
Spillane, Nichea S.; Merrill, Jennifer E.; Jackson, Kristina M.
2016-01-01
Studies on adolescent drinking have not always been able to distinguish between initiation and escalation of drinking, because many studies include samples in which initiation has already occurred; hence initiation and escalation are often confounded. The present study draws from a dual-process theoretical framework to investigate: if changes in the likelihood of drinking initiation and escalation are predicted by a tendency towards rash action when experiencing positive and negative emotions (positive and negative urgency); and whether trait positive and negative affect moderate such effects. Alcohol naïve adolescents (n=944; age: M=12.16, SD=.96; 52% female) completed 6 semi-annual assessments of trait urgency and affect (wave-1) and alcohol use (waves 2–6). A two-part random-effects model was used to estimate changes in the likelihood of any alcohol use vs. escalation in the volume of use amongst initiators. Main effects suggest a significant association between positive affect and change in level of alcohol use amongst initiators, such that lower positive affect predicted increased alcohol involvement. This main effect was qualified by a significant interaction between positive urgency and positive affect predicting changes in the escalation of drinking, such that the effect of positive urgency was augmented for those high on trait positive affect, though only at extremely high levels of positive affect. Results suggest risk factors in the development of drinking depend on whether initiation or escalation is investigated. A more nuanced understanding of the early developmental phases of alcohol involvement can inform prevention and intervention efforts. PMID:27031086
Ryu, Jihye; Lee, Chaeyoung
2014-12-01
Positive selection not only increases beneficial allele frequency but also causes augmentation of allele frequencies of sequence variants in close proximity. Signals for positive selection were detected by the statistical differences in subsequent allele frequencies. To identify selection signatures in Korean cattle, we applied a composite log-likelihood (CLL)-based method, which calculates a composite likelihood of the allelic frequencies observed across sliding windows of five adjacent loci and compares the value with the critical statistic estimated by 50,000 permutations. Data for a total of 11,799 nucleotide polymorphisms were used with 71 Korean cattle and 209 foreign beef cattle. As a result, 147 signals were identified for Korean cattle based on CLL estimates (P < 0.01). The signals might be candidate genetic factors for meat quality by which the Korean cattle have been selected. Further genetic association analysis with 41 intragenic variants in the selection signatures with the greatest CLL for each chromosome revealed that marbling score was associated with five variants. Intensive association studies with all the selection signatures identified in this study are required to exclude signals associated with other phenotypes or signals falsely detected and thus to identify genetic markers for meat quality. © 2014 Stichting International Foundation for Animal Genetics.
Female breast symptoms in patients attended in the family medicine practice.
González-Pérez, Brian; Salas-Flores, Ricardo; Sosa-López, María Lucero; Barrientos-Guerrero, Carlos Eduardo; Hernández-Aguilar, Claudia Magdalena; Gómez-Contreras, Diana Edith; Sánchez-Garza, Jorge Arturo
2013-01-01
there are few studies on breast symptoms (BS) in patients attended at primary care units in Mexico. The aim was to determine the frequency and types of BS overall and by age-group and establish which BS were related to diagnosis of breast cancer. data from all female patients with a breast-disease-related diagnosis, attended from 2006 to 2010, at the Family Medicine Unit 38, were collected. The frequencies of BS were determined by four age-groups (< 19, 20-49, 50-69, > 70 years) and likelihood ratios for breast cancer for each breast-related symptom patient, with a 95 % confidence interval (CI). the most frequent BS in the study population were lump/mass (71.7 %) and breast pain (67.7 %) of all breast complaints, and they were more noted in women age group of 20-49 years. Overall, 120 women had breast cancer diagnosed with a median age of 53.51 + 12.7 years. Breast lump/mass had positive likelihood ratios for breast cancer 4.53 (95 % CI = 2.51-8.17) and breast pain had increased negative LR = 1.08 (95 % CI = 1.05-1.11). breast lump/mass was the predominant presenting complaint among females with breast symptoms in our primary care unit, and it was associated with elevated positive likelihood of breast cancer.
The meaning of diagnostic test results: a spreadsheet for swift data analysis.
Maceneaney, P M; Malone, D E
2000-03-01
To design a spreadsheet program to: (a) analyse rapidly diagnostic test result data produced in local research or reported in the literature; (b) correct reported predictive values for disease prevalence in any population; (c) estimate the post-test probability of disease in individual patients. Microsoft Excel(TM)was used. Section A: a contingency (2 x 2) table was incorporated into the spreadsheet. Formulae for standard calculations [sample size, disease prevalence, sensitivity and specificity with 95% confidence intervals, predictive values and likelihood ratios (LRs)] were linked to this table. The results change automatically when the data in the true or false negative and positive cells are changed. Section B: this estimates predictive values in any population, compensating for altered disease prevalence. Sections C-F: Bayes' theorem was incorporated to generate individual post-test probabilities. The spreadsheet generates 95% confidence intervals, LRs and a table and graph of conditional probabilities once the sensitivity and specificity of the test are entered. The latter shows the expected post-test probability of disease for any pre-test probability when a test of known sensitivity and specificity is positive or negative. This spreadsheet can be used on desktop and palmtop computers. The MS Excel(TM)version can be downloaded via the Internet from the URL ftp://radiography.com/pub/Rad-data99.xls A spreadsheet is useful for contingency table data analysis and assessment of the clinical meaning of diagnostic test results. Copyright 2000 The Royal College of Radiologists.