Performance Evaluation of a Novel Chemiluminescence Assay Detecting Treponema Pallidum Antibody as a Syphilis Screening Method.

PubMed

Chen, Qixia; An, Jingna; Rao, Chenli; Wang, Tingting; Li, Dongdong; Feng, Shu; Tao, Chuanmin

2016-01-01

Syphilis is a major concern to global public health with increasing incidence. So its screening test should have sufficient sensitivity and specificity. We evaluated the performance of the Lumipulse G TP-N assay detection for syphilis screening and compared it with the InTec ELISA test kit for TP, which is widely used. Samples of several patient groups including 133 clinical and serologically characterized syphilitic sera, 175 samples containing potentially interfering agents, and 2290 unselected samples submitted for routine screening were detected by both the Lumipulse G TP-N assay and the InTec ELISA test kit for TP. Inconsistent samples were confirmed by RecomLine Treponema IgG, IgM immunoblot. Coefficient of variations of the Lumipulseo G TP-N assay at both levels were below 5% and of the InTec ELISA test kit for TP both over 5%. The sensitivity of the Lumipulse G TP-N assay and the InTec ELISA test kit for TP were 100% for all stages of syphilis. The two methods had consistent analytical specificity of 100% (95% CI: 97.21 - 100.00), while the clinical specificity was 100% (95% CI: 99.79 - 100.00) and 99.82% (95% CI: 99.51 - 99.94), respectively. Between them, Spearman's correlation coefficient was 0.455 and kappa value was 0.986. The overall sensitivity and specificity of the Lumipulse G TP-N assay was higher than the InTec ELISA test kit for TP (sensitivity: 100.0 versus 99.5, specificity: 100.0 versus 99.8). The automated Lumipulse G TP-N assay demonstrated excellent diagnostic sensitivity and specificity when evaluated as a screening test for syphilis. Thus, it can be an alternative to the treponemal screening test.

A Performance Comparison of Color Vision Tests for Military Screening.

PubMed

Walsh, David V; Robinson, James; Jurek, Gina M; Capó-Aponte, José E; Riggs, Daniel W; Temme, Leonard A

2016-04-01

Current color vision (CV) tests used for aviation screening in the U.S. Army only provide pass-fail results, and previous studies have shown variable sensitivity and specificity. The purpose of this study was to evaluate seven CV tests to determine an optimal CV test screener that potentially could be implemented by the U.S. Army. There were 133 subjects [65 Color Vision Deficits (CVD), 68 Color Vision Normal (CVN)] who performed all of the tests in one setting. CVD and CVN determination was initially assessed with the Oculus anomaloscope. Each test was administered monocularly and according to the test protocol. The main outcome measures were test sensitivity, specificity, and administration time (automated tests). Three of the four Pseudoisochromatic Plate (PIP) tests had a sensitivity/specificity > 0.90 OD/OS, whereas the FALANT tests had a sensitivity/specificity > 0.80 OD/OS. The Cone Contrast Test (CCT) demonstrated sensitivity/specificity > 0.90 OD/OS, whereas the Color Assessment and Diagnosis (CAD) test demonstrated sensitivity/specificity > 0.85 OD/OS. Comparison with the anomaloscope ("gold standard") revealed no significant difference of sensitivity and specificity OD/OS with the CCT, Dvorine PIP, and PIPC tests. Finally, the CCT administration time was significantly faster than the CAD test. The current U.S. Army CV screening tests demonstrated good sensitivity and specificity, as did the automated tests. In addition, some current PIP tests (Dvorine, PIPC), and the CCT performed no worse statistically than the anomaloscope with regard to sensitivity/specificity. The CCT letter presentation is randomized and results would not be confounded by potential memorization, or fading, of book plates.

Comparison of real-time PCR with disk diffusion, agar screen and E-test methods for detection of methicillin-resistant Staphylococcus aureus.

PubMed

Shariati, Laleh; Validi, Majid; Tabatabaiefar, Mohammad Amin; Karimi, Ali; Nafisi, Mohammad Reza

2010-12-01

Methicillin-resistant Staphylococcus aureus (MRSA) is a nosocomial pathogen. Our main objective was to compare oxacillin disk test, oxacillin E-test, and oxacillin agar screen for detection of methicillin resistance in S. aureus, using real-time PCR for mecA as the "gold standard" comparison assay. 196 S. aureus isolates were identified out of 284 Staphylococcus isolates. These isolates were screened for MRSA with several methods: disk diffusion, agar screen (6.0 μg/ml), oxacillin E-test, and real-time PCR for detection of mecA gene. Of the 196 S. aureus isolates tested, 96 isolates (49%) were mecA-positive and 100 isolates (51%) mecA-negative. All methods tested had a statistically significant agreement with real-time PCR. E-test was 100% sensitive and specific for mecA presence. The sensitivity and specificity of oxacillin agar screen method were 98 and 99%, respectively and sensitivity and specificity of oxacillin disk diffusion method were 95 and 93%, respectively. In the present study, oxacillin E-test is proposed as the best phenotypic method. For economic reasons, the oxacillin agar screen method (6.0 μg/ml), which is suitable for the detection of MRSA, is recommended due to its accuracy and low cost.

A comparison of an immunological faecal occult blood test Fecatwin sensitive/FECA EIA with Haemoccult in population screening for colorectal cancer.

PubMed Central

Armitage, N.; Hardcastle, J. D.; Amar, S. S.; Balfour, T. W.; Haynes, J.; James, P. D.

1985-01-01

Two faecal occult blood tests, a simple chemical test Haemoccult and an immunological test, Fecatwin Sensitive/Feca EIA, were offered to 3,225 asymptomatic individuals as screening for colorectal cancer. One thousand three hundred and four (44%) completed and returned the tests and of these 126 (9.7%) were found to be positive - Haemoccult 40 (3%) and Feca EIA 106 (8.1%). Five cancers (4 Dukes' Stage A, 1 Dukes' Stage C) and 23 adenomas greater than 1 cm were detected - rates of 3.8 per 1000 persons screened and 17.7 per 1000 persons screened respectively. Of the five cancers identified 5 were Feca EIA positive and 3 were Haemoccult positive. Of the 23 adenomas greater than 1 cm diameter identified, J1 were Feca EIA positive and 20 were Haemoccult positive. Seventy-eight Feca EIA positive subjects were investigated and no neoplastic disease was identified. Whilst this sensitive immunological test increases the yield of carcinomas, the high false positive rate makes it unsuitable for population screening for colorectal cancer in its present form. PMID:4005139

Plasma Septin9 versus Fecal Immunochemical Testing for Colorectal Cancer Screening: A Prospective Multicenter Study

PubMed Central

Johnson, David A.; Barclay, Robert L.; Mergener, Klaus; Weiss, Gunter; König, Thomas; Beck, Jürgen; Potter, Nicholas T.

2014-01-01

Background Screening improves outcomes related to colorectal cancer (CRC); however, suboptimal participation for available screening tests limits the full benefits of screening. Non-invasive screening using a blood based assay may potentially help reach the unscreened population. Objective To compare the performance of a new Septin9 DNA methylation based blood test with a fecal immunochemical test (FIT) for CRC screening. Design: In this trial, fecal and blood samples were obtained from enrolled patients. To compare test sensitivity for CRC, patients with screening identified colorectal cancer (n = 102) were enrolled and provided samples prior to surgery. To compare test specificity patients were enrolled prospectively (n = 199) and provided samples prior to bowel preparation for screening colonoscopy. Measurements Plasma and fecal samples were analyzed using the Epi proColon and OC Fit-Check tests respectively. Results For all samples, sensitivity for CRC detection was 73.3% (95% CI 63.9–80.9%) and 68.0% (95% CI 58.2–76.5%) for Septin9 and FIT, respectively. Specificity of the Epi proColon test was 81.5% (95% CI 75.5–86.3%) compared with 97.4% (95% CI 94.1–98.9%) for FIT. For paired samples, the sensitivity of the Epi proColon test (72.2% –95% CI 62.5–80.1%) was shown to be statistically non-inferior to FIT (68.0%–95% CI 58.2–76.5%). When test results for Epi proColon and FIT were combined, CRC detection was 88.7% at a specificity of 78.8%. Conclusions At a sensitivity of 72%, the Epi proColon test is non- inferior to FIT for CRC detection, although at a lower specificity. With negative predictive values of 99.8%, both methods are identical in confirming the absence of CRC. Trial Registration ClinicalTrials.gov NCT01580540 PMID:24901436

Bias in estimating accuracy of a binary screening test with differential disease verification

PubMed Central

Brinton, John T.; Ringham, Brandy M.; Glueck, Deborah H.

2011-01-01

SUMMARY Sensitivity, specificity, positive and negative predictive value are typically used to quantify the accuracy of a binary screening test. In some studies it may not be ethical or feasible to obtain definitive disease ascertainment for all subjects using a gold standard test. When a gold standard test cannot be used an imperfect reference test that is less than 100% sensitive and specific may be used instead. In breast cancer screening, for example, follow-up for cancer diagnosis is used as an imperfect reference test for women where it is not possible to obtain gold standard results. This incomplete ascertainment of true disease, or differential disease verification, can result in biased estimates of accuracy. In this paper, we derive the apparent accuracy values for studies subject to differential verification. We determine how the bias is affected by the accuracy of the imperfect reference test, the percent who receive the imperfect reference standard test not receiving the gold standard, the prevalence of the disease, and the correlation between the results for the screening test and the imperfect reference test. It is shown that designs with differential disease verification can yield biased estimates of accuracy. Estimates of sensitivity in cancer screening trials may be substantially biased. However, careful design decisions, including selection of the imperfect reference test, can help to minimize bias. A hypothetical breast cancer screening study is used to illustrate the problem. PMID:21495059

Epi proColon® 2.0 CE: A Blood-Based Screening Test for Colorectal Cancer.

PubMed

Lamb, Yvette N; Dhillon, Sohita

2017-04-01

Epi proColon ® 2.0 CE is a blood-based test designed to aid in the early detection of colorectal cancer. The test comprises a qualitative assay for the polymerase chain reaction (PCR) detection of methylated Septin9 DNA, the presence of which is associated with colorectal cancer: however, positive results should be verified by colonoscopy or sigmoidoscopy. Epi proColon ® 2.0 CE discriminated between patients with colorectal cancer and healthy controls with high clinical sensitivity and specificity in pivotal case-control studies. The sensitivity of the test did not appear to be affected by the tumour location or by patient age or gender. In addition, limited data suggest that Epi proColon ® 2.0 CE discriminated between patients with colorectal cancer and healthy controls with higher sensitivity and generally similar specificity to that of the faecal immunochemical test, and with higher sensitivity and specificity to that of the guaiac-based faecal occult blood test (statistical data not available). In an observational study, most patients who refused colonoscopy for screening accepted a non-invasive test option as an alternative, and preferred Epi proColon ® 2.0 CE over a stool-based test. Large prospective trials of Epi proColon ® 2.0 CE in a screening setting will be required to further elucidate the cost-effectiveness of the test. Nevertheless, currently available data suggests that Epi proColon ® 2.0 CE has the potential to be a sensitive and convenient screening option for patients refusing screening by colonoscopy.

The cost-effectiveness of screening for colorectal cancer.

PubMed

Telford, Jennifer J; Levy, Adrian R; Sambrook, Jennifer C; Zou, Denise; Enns, Robert A

2010-09-07

Published decision analyses show that screening for colorectal cancer is cost-effective. However, because of the number of tests available, the optimal screening strategy in Canada is unknown. We estimated the incremental cost-effectiveness of 10 strategies for colorectal cancer screening, as well as no screening, incorporating quality of life, noncompliance and data on the costs and benefits of chemotherapy. We used a probabilistic Markov model to estimate the costs and quality-adjusted life expectancy of 50-year-old average-risk Canadians without screening and with screening by each test. We populated the model with data from the published literature. We calculated costs from the perspective of a third-party payer, with inflation to 2007 Canadian dollars. Of the 10 strategies considered, we focused on three tests currently being used for population screening in some Canadian provinces: low-sensitivity guaiac fecal occult blood test, performed annually; fecal immunochemical test, performed annually; and colonoscopy, performed every 10 years. These strategies reduced the incidence of colorectal cancer by 44%, 65% and 81%, and mortality by 55%, 74% and 83%, respectively, compared with no screening. These strategies generated incremental cost-effectiveness ratios of $9159, $611 and $6133 per quality-adjusted life year, respectively. The findings were robust to probabilistic sensitivity analysis. Colonoscopy every 10 years yielded the greatest net health benefit. Screening for colorectal cancer is cost-effective over conventional levels of willingness to pay. Annual high-sensitivity fecal occult blood testing, such as a fecal immunochemical test, or colonoscopy every 10 years offer the best value for the money in Canada.

Diagnostic Validity of High-Density Barium Sulfate in Gastric Cancer Screening: Follow-up of Screenees by Record Linkage with the Osaka Cancer Registry

PubMed Central

Yamamoto, Kenyu; Yamazaki, Hideo; Kuroda, Chikazumi; Kubo, Tsugio; Oshima, Akira; Katsuda, Toshizo; Kuwano, Tadao; Takeda, Yoshihiro

2010-01-01

Background The use of high-density barium sulfate was recommended by the Japan Society of Gastroenterological Cancer Screening (JSGCS) in 2004. We evaluated the diagnostic validity of gastric cancer screening that used high-density barium sulfate. Methods The study subjects were 171 833 residents of Osaka, Japan who underwent gastric cancer screening tests at the Osaka Cancer Prevention and Detection Center during the period from 1 January 2000 through 31 December 2001. Screening was conducted using either high-density barium sulfate (n = 48 336) or moderate-density barium sulfate (n = 123 497). The subjects were followed up and their medical records were linked to those of the Osaka Cancer Registry through 31 December 2002. The results of follow-up during 1 year were defined as the gold standard, and test performance values were calculated. Results The sensitivity and specificity of the screening test using moderate-density barium sulfate were 92.3% and 91.0%, respectively, while the sensitivity and specificity of the high-density barium test were 91.8% and 91.4%, respectively. The results of area under receiver-operating-characteristic (ROC) curve analysis revealed no significant difference between the 2 screening tests. Conclusions Screening tests using high- and moderate-density barium sulfate had similar validity, as determined by sensitivity, specificity, and ROC curve analysis. PMID:20551581

The sensitivity and specificity of subjective memory complaints and the subjective memory rating scale, deterioration cognitive observee, mini-mental state examination, six-item screener and clock drawing test in dementia screening.

PubMed

Ramlall, S; Chipps, J; Bhigjee, A I; Pillay, B J

2013-01-01

The effectiveness of dementia screening depends on the availability of suitable screening tools with good sensitivity and specificity to confidently distinguish normal age-related cognitive decline from dementia. The aim of this study was to evaluate the discriminant validity of 7 screening measures for dementia. A sample of 140 participants aged ≥60 years living in a residential facility for the aged were assessed clinically and assigned caseness for dementia using the Diagnostic and Statistical Manual of Mental Disorders, 4th edition, text revised diagnostic criteria. Sensitivity and specificity of a selection of the following screening measures were tested using receiver operating characteristic (ROC) analysis for individual and combined tests: the Mini-Mental State Examination (MMSE), Six-Item Screener (SIS), Subjective Memory Complaint, Subjective Memory Complaint Clinical (SMCC), Subjective Memory Rating Scale (SMRS), Deterioration Cognitive Observee (DECO) and the Clock Drawing Test (CDT). Using ROC analyses, the SMCC, MMSE and CDT were found to be 'moderately accurate' in screening for dementia with an area under the curve (AUC) >0.70. The AUCs for the SIS (0.526), SMRS (0.661) and DECO (0.687) classified these measures as being 'less accurate'. At recommended cutoff scores, the SMCC had a sensitivity of 90.9% and specificity of 45.7%; the MMSE had a sensitivity of 63.6% and a specificity of 76.0%, and the CDT had a sensitivity of 44.4% and a specificity of 88.9%. Combining the SMCC and MMSE did not improve their predictive power except for a modest increase when using the sequential rule. The SMCC is composed of valid screening questions that have high sensitivity, are simple to administer and ideal for administration at the community or primary health care level as a first level of 'rule-out' screening. The MMSE can be included at a second stage of screening at the general hospital level and the CDT in specialist clinical settings. Sequential use of the SMCC and MMSE will improve the specificity of the former and the sensitivity of the latter. Copyright © 2013 S. Karger AG, Basel.

A Smartphone App to Screen for HIV-Related Neurocognitive Impairment.

PubMed

Robbins, Reuben N; Brown, Henry; Ehlers, Andries; Joska, John A; Thomas, Kevin G F; Burgess, Rhonda; Byrd, Desiree; Morgello, Susan

2014-02-01

Neurocognitive Impairment (NCI) is one of the most common complications of HIV-infection, and has serious medical and functional consequences. However, screening for it is not routine and NCI often goes undiagnosed. Screening for NCI in HIV disease faces numerous challenges, such as limited screening tests, the need for specialized equipment and apparatuses, and highly trained personnel to administer, score and interpret screening tests. To address these challenges, we developed a novel smartphone-based screening tool, NeuroScreen , to detect HIV-related NCI that includes an easy-to-use graphical user interface with ten highly automated neuropsychological tests. To examine NeuroScreen's : 1) acceptability among patients and different potential users; 2) test construct and criterion validity; and 3) sensitivity and specificity to detect NCI. Fifty HIV+ individuals were administered a gold-standard neuropsychological test battery, designed to detect HIV-related NCI, and NeuroScreen . HIV+ test participants and eight potential provider-users of NeuroScreen were asked about its acceptability. There was a high level of acceptability of NeuroScreen by patients and potential provider-users. Moderate to high correlations between individual NeuroScreen tests and paper-and-pencil tests assessing the same cognitive domains were observed. NeuroScreen also demonstrated high sensitivity to detect NCI. NeuroScreen, a highly automated, easy-to-use smartphone-based screening test to detect NCI among HIV patients and usable by a range of healthcare personnel could help make routine screening for HIV-related NCI feasible. While NeuroScreen demonstrated robust psychometric properties and acceptability, further testing with larger and less neurocognitively impaired samples is warranted.

Accuracy and Cost-Effectiveness of Cervical Cancer Screening by High-Risk HPV DNA Testing of Self-Collected Vaginal Samples

PubMed Central

Balasubramanian, Akhila; Kulasingam, Shalini L.; Baer, Atar; Hughes, James P.; Myers, Evan R.; Mao, Constance; Kiviat, Nancy B.; Koutsky, Laura A.

2010-01-01

Objective Estimate the accuracy and cost-effectiveness of cervical cancer screening strategies based on high-risk HPV DNA testing of self-collected vaginal samples. Materials and Methods A subset of 1,665 women (18-50 years of age) participating in a cervical cancer screening study were screened by liquid-based cytology and by high-risk HPV DNA testing of both self-collected vaginal swab samples and clinician-collected cervical samples. Women with positive/abnormal screening test results and a subset of women with negative screening test results were triaged to colposcopy. Based on individual and combined test results, five screening strategies were defined. Estimates of sensitivity and specificity for cervical intraepithelial neoplasia grade 2 or worse were calculated and a Markov model was used to estimate the incremental cost-effectiveness ratios (ICERs) for each strategy. Results Compared to cytology-based screening, high-risk HPV DNA testing of self-collected vaginal samples was more sensitive (68%, 95%CI=58%-78% versus 85%, 95%CI=76%-94%) but less specific (89%, 95%CI=86%-91% versus 73%, 95%CI=67%-79%). A strategy of high-risk HPV DNA testing of self-collected vaginal samples followed by cytology triage of HPV positive women, was comparably sensitive (75%, 95%CI=64%-86%) and specific (88%, 95%CI=85%-92%) to cytology-based screening. In-home self-collection for high-risk HPV DNA detection followed by in-clinic cytology triage had a slightly lower lifetime cost and a slightly higher quality-adjusted life expectancy than did cytology-based screening (ICER of triennial screening compared to no screening was $9,871/QALY and $12,878/QALY, respectively). Conclusions Triennial screening by high-risk HPV DNA testing of in-home, self-collected vaginal samples followed by in-clinic cytology triage was cost-effective. PMID:20592553

Laboratory audit as part of the quality assessment of a primary HPV-screening program.

PubMed

Hortlund, Maria; Sundström, Karin; Lamin, Helena; Hjerpe, Anders; Dillner, Joakim

2016-02-01

As primary HPV screening programs are rolled out, methods are needed for routine quality assurance of HPV laboratory analyzes. To explore the use of similar design for audit as currently used in cytology-based screening, to estimate the clinical sensitivity to identify women at risk for CIN 3 or worse (CIN3+). Population-based cohort study conducted within the cervical screening program in Stockholm, Sweden, in 2011-2012. All women with histopathologically confirmed CIN3+ in the following two years were identified by registry analysis. Primary HPV and cytology screening results were collected. For women who had not been HPV tested, biobanked cytology samples were HPV-tested. If the original HPV result had been negative, the sample and subsequent biopsies were analyzed with broad HPV typing (general primer PCR and Luminex). 154 women had a biobanked prediagnostic cytology sample taken up to 2 years before a histopathologically confirmed CIN3+. The high-risk HPV-positivity was 97% (148/154 women), whereas 143/154 (94%) women had had a cytological abnormality. Among the six HPV-negative samples, one sample was HPV 33 positive in repeat testing whereas the other five cases were HPV-negative also on repeat testing, but HPV-positive in the subsequent tumor tissue. A sensitivity of the HPV test that is higher than the sensitivity of cytology suggests adequate quality of the testing. Regular audits of clinical sensitivity, similar to those of cytology-based screening, should be used also in HPV-based screening programs, in order to continuously monitor the performance of the analyzes. Copyright © 2015 Elsevier B.V. All rights reserved.

Sensitivity, Specificity, and Predictive Values: Foundations, Pliabilities, and Pitfalls in Research and Practice

PubMed Central

Trevethan, Robert

2017-01-01

Within the context of screening tests, it is important to avoid misconceptions about sensitivity, specificity, and predictive values. In this article, therefore, foundations are first established concerning these metrics along with the first of several aspects of pliability that should be recognized in relation to those metrics. Clarification is then provided about the definitions of sensitivity, specificity, and predictive values and why researchers and clinicians can misunderstand and misrepresent them. Arguments are made that sensitivity and specificity should usually be applied only in the context of describing a screening test’s attributes relative to a reference standard; that predictive values are more appropriate and informative in actual screening contexts, but that sensitivity and specificity can be used for screening decisions about individual people if they are extremely high; that predictive values need not always be high and might be used to advantage by adjusting the sensitivity and specificity of screening tests; that, in screening contexts, researchers should provide information about all four metrics and how they were derived; and that, where necessary, consumers of health research should have the skills to interpret those metrics effectively for maximum benefit to clients and the healthcare system. PMID:29209603

The New Technologies for Cervical Cancer Screening randomised controlled trial. An overview of results during the first phase of recruitment.

PubMed

Ronco, Guglielmo; Brezzi, Silvia; Carozzi, Francesca; Dalla Palma, Paolo; Giorgi-Rossi, Paolo; Minucci, Daria; Naldoni, Carlo; Segnan, Nereo; Zappa, Marco; Zorzi, Manuel; Cuzick, Jack

2007-10-01

To study the impact of different cervical cancer screening strategies including HPV testing. A randomised controlled trial with a conventional arm (conventional cytology) and an experimental arm following two phases (first HPV testing+conventional cytology, second HPV testing alone). In phase one, different protocols were applied to different age groups (25-34 and 35-60). Published data on test accuracy during the phase one of recruitment are summarised. 45,307 women were recruited in phase one (about 95,000 overall). In the age group 35-60, HPV testing (by Hybrid Capture 2) alone at 2 RLU cut-off increased sensitivity vs. conventional cytology (relative sensitivity 1.41; 95% CI: 0.98-1.02) with a small loss in Positive Predictive Value (PPV; relative PPV 0.75; 95% CI: 0.45-1.25). Adding liquid-based cytology as screening test and referring to colposcopy women positive to either only marginally increased sensitivity but strongly reduced PPV. In the age group 25-34, similar results (relative sensitivity vs. conventional cytology 1.58; 95% CI: 1.032.44; relative PPV 0.78; 95% CI: 0.72-1.16) were obtained, despite 14% of women were HPV positive, with a strategy based on HPV alone as screening test, triaging HPV positive women by cytology, directly referring those ASCUS+ to colposcopy and repeating both tests after 1 year in those with normal cytology. HPV testing, if used as screening test, should be applied alone, with cytology triage essential in younger women but preferable at all ages. Follow-up data will allow analysis of the safety of prolonging screening intervals and the relative persistence of lesions detected with different methods.

The role of oncogenic human papillomavirus determination for diagnosis of high-grade anal intraepithelial neoplasia in HIV-infected MSM.

PubMed

Burgos, Joaquin; Hernández-Losa, Javier; Landolfi, Stefania; Guelar, Ana; Dinares, MªCarmen; Villar, Judith; Navarro, Jordi; Ribera, Esteve; Falcó, Vicenç; Curran, Adria

2017-10-23

To assess the oncogenic human papillomavirus (HPV) determination and the cotesting HPV and anal cytology value to detect high-grade anal intraepithelial neoplasia (HGAIN) in a cohort of HIV-MSM. Prospective study of HIV-infected MSM who underwent screening for anal dysplasia. Screening program includes anal cytology, HPV testing, and high-resolution anoscopy (HRA) at each visit. Histological samples were obtained if suspicious lesions were revealed by HRA. Sensitivity and specificity of the different tests were calculated by using histological results of HRA-guided biopsy as the reference test for HGAIN diagnosis. From May 2009 to August 2016, 692 HIV-infected MSM underwent 1827 anal cytologies, 1841 HRA examinations, and 1607 HPV testing. At first screening visit, anal cytology results were abnormal in 418 (60.4%) of 692 patients, and oncogenic HPV genotypes were found in 482 (79.5%) of 606 patients. Anal cytology showed a sensitivity of 89.2% [95% confidence interval (CI); 80.7-94.2] and a specificity of 44.2% (95% CI; 40.2-48.2) to detect HGAIN. Oncogenic HPV testing had 90.4% sensitivity (95% CI; 82-86.8) and 24.4% specificity (95% CI; 20.8-28.3). Cotesting showed a 97.4% sensitivity (95% CI; 91-99.3) and 14% specificity (95% CI; 11.2-17.3). In patients with atypical squamous cells of uncertain significance on cytology, oncogenic HPV testing had 91.3% sensitivity and 28.3% specificity to detect HGAIN. Abnormal cytology and oncogenic HPV determination showed similar sensitivity for detecting HGAIN. The two tests used together improved the sensitivity but with lowered specificity. In our opinion, HPV testing does not improve HGAIN detection and should not replace anal cytology as a standard screening test for HIV-infected MSM.

A Smartphone App to Screen for HIV-Related Neurocognitive Impairment

PubMed Central

Robbins, Reuben N.; Brown, Henry; Ehlers, Andries; Joska, John A.; Thomas, Kevin G.F.; Burgess, Rhonda; Byrd, Desiree; Morgello, Susan

2014-01-01

Background Neurocognitive Impairment (NCI) is one of the most common complications of HIV-infection, and has serious medical and functional consequences. However, screening for it is not routine and NCI often goes undiagnosed. Screening for NCI in HIV disease faces numerous challenges, such as limited screening tests, the need for specialized equipment and apparatuses, and highly trained personnel to administer, score and interpret screening tests. To address these challenges, we developed a novel smartphone-based screening tool, NeuroScreen, to detect HIV-related NCI that includes an easy-to-use graphical user interface with ten highly automated neuropsychological tests. Aims To examine NeuroScreen’s: 1) acceptability among patients and different potential users; 2) test construct and criterion validity; and 3) sensitivity and specificity to detect NCI. Methods Fifty HIV+ individuals were administered a gold-standard neuropsychological test battery, designed to detect HIV-related NCI, and NeuroScreen. HIV+ test participants and eight potential provider-users of NeuroScreen were asked about its acceptability. Results There was a high level of acceptability of NeuroScreen by patients and potential provider-users. Moderate to high correlations between individual NeuroScreen tests and paper-and-pencil tests assessing the same cognitive domains were observed. NeuroScreen also demonstrated high sensitivity to detect NCI. Conclusion NeuroScreen, a highly automated, easy-to-use smartphone-based screening test to detect NCI among HIV patients and usable by a range of healthcare personnel could help make routine screening for HIV-related NCI feasible. While NeuroScreen demonstrated robust psychometric properties and acceptability, further testing with larger and less neurocognitively impaired samples is warranted. PMID:24860624

Improving Detection of HIV-Associated Cognitive Impairment: Comparison of the International HIV Dementia Scale and a Brief Screening Battery.

PubMed

de Almeida, Sérgio Monteiro; Kamat, Rujvi; Cherner, Mariana; Umlauf, Anya; Ribeiro, Clea E; de Pereira, Ana Paula; Franklin, Donald; Heaton, Robert K; Ellis, Ronald J

2017-03-01

The International HIV Dementia Scale (IHDS) was developed to screen for HIV-associated dementia, but it has been used more generally for HIV-associated neurocognitive disorder (HAND). This study sought to examine the accuracy of the IHDS in a cohort of Brazilian HIV-infected individuals and compare its performance to an alternative screening battery for detecting HAND. A total of 108 participants (including 60 HIV-infected persons) completed the IHDS and a gold standard neuropsychological (NP) battery of 17 tests. As alternative screening method, all possible 3-test combinations from the NP battery were examined and a superiority index (a marker of specificity and sensitivity) was calculated. Sensitivity and specificity to HAND using the standard IHDS cutpoint of 10 were 36% and 75%, respectively. The best balance between sensitivity and specificity was accomplished with a modified cutpoint of 11.5, which yielded sensitivity of 72% and specificity of 58%. The top two most sensitive test combinations, compared with the gold standard NP battery, were Trail Making Test A, Wechsler Adult Intelligence Scale III Digit Symbol and Hopkins Verbal Learning Test-Revised Total Recall (sensitivity 91%, specificity 96%), and Digit Symbol, Brief Visuospatial Memory Test-Revised Total Recall and Grooved Pegboard Test-dominant hand (sensitivity 94%, specificity 91%). Both test combinations can be administered in less than 10 minutes and were more accurate than the IHDS in classifying HIV+ participants as NP impaired or unimpaired. These data suggest that demographically corrected T-scores from commonly used NP measures with modest time and material demands can improve identification of patients with HAND who may benefit from a more extensive NP examination.

Population and High-Risk Group Screening for Glaucoma: The Los Angeles Latino Eye Study

PubMed Central

Francis, Brian A.; Vigen, Cheryl; Lai, Mei-Ying; Winarko, Jonathan; Nguyen, Betsy; Azen, Stanley

2011-01-01

Purpose. To evaluate the ability of various screening tests, both individually and in combination, to detect glaucoma in the general Latino population and high-risk subgroups. Methods. The Los Angeles Latino Eye Study is a population-based study of eye disease in Latinos 40 years of age and older. Participants (n = 6082) underwent Humphrey visual field testing (HVF), frequency doubling technology (FDT) perimetry, measurement of intraocular pressure (IOP) and central corneal thickness (CCT), and independent assessment of optic nerve vertical cup disc (C/D) ratio. Screening parameters were evaluated for three definitions of glaucoma based on optic disc, visual field, and a combination of both. Analyses were also conducted for high-risk subgroups (family history of glaucoma, diabetes mellitus, and age ≥65 years). Sensitivity, specificity, and receiver operating characteristic curves were calculated for those continuous parameters independently associated with glaucoma. Classification and regression tree (CART) analysis was used to develop a multivariate algorithm for glaucoma screening. Results. Preset cutoffs for screening parameters yielded a generally poor balance of sensitivity and specificity (sensitivity/specificity for IOP ≥21 mm Hg and C/D ≥0.8 was 0.24/0.97 and 0.60/0.98, respectively). Assessment of high-risk subgroups did not improve the sensitivity/specificity of individual screening parameters. A CART analysis using multiple screening parameters—C/D, HVF, and IOP—substantially improved the balance of sensitivity and specificity (sensitivity/specificity 0.92/0.92). Conclusions. No single screening parameter is useful for glaucoma screening. However, a combination of vertical C/D ratio, HVF, and IOP provides the best balance of sensitivity/specificity and is likely to provide the highest yield in glaucoma screening programs. PMID:21245400

Sensitivity of caloric test and video head impulse as screening test for chronic vestibular complaints.

PubMed

Mezzalira, Raquel; Bittar, Roseli Saraiva Moreira; do Carmo Bilécki-Stipsky, Marcia Maria; Brugnera, Cibele; Grasel, Signe Schuster

2017-08-01

This study compared the results of the caloric test with those of the video head impulse test obtained during the same session and evaluated whether the former can be used to screen for non-acute vestibular dysfunction. A total of 157 participants complaining of dizziness with vestibular characteristics of varying durations and clinical courses completed the caloric test and video head impulse test. Significantly more caloric test results than video head impulse test results were abnormal. The results of the caloric test and video head impulse test are distinct but complement each other. Within our sample, the caloric test was more sensitive for vestibular dysfunction. Therefore, the video head impulse test is not a suitable screening tool of the vestibular system in patients with chronic complaints.

A user-operated test of suprathreshold acuity in noise for adult hearing screening: The SUN (Speech Understanding in Noise) test.

PubMed

Paglialonga, Alessia; Tognola, Gabriella; Grandori, Ferdinando

2014-09-01

A novel, user-operated test of suprathreshold acuity in noise for use in adult hearing screening (AHS) was developed. The Speech Understanding in Noise test (SUN) is a speech-in-noise test that makes use of a list of vowel-consonant-vowel (VCV) stimuli in background noise presented in a three-alternative forced choice (3AFC) paradigm by means of a touch sensitive screen. The test is automated, easy-to-use, and provides self-explanatory results (i.e., 'no hearing difficulties', or 'a hearing check would be advisable', or 'a hearing check is recommended'). The test was developed from its building blocks (VCVs and speech-shaped noise) through two main steps: (i) development of the test list through equalization of the intelligibility of test stimuli across the set and (ii) optimization of the test results through maximization of the test sensitivity and specificity. The test had 82.9% sensitivity and 85.9% specificity compared to conventional pure-tone screening, and 83.8% sensitivity and 83.9% specificity to identify individuals with disabling hearing impairment. Results obtained so far showed that the test could be easily performed by adults and older adults in less than one minute per ear and that its results were not influenced by ambient noise (up to 65dBA), suggesting that the test might be a viable method for AHS in clinical as well as non-clinical settings. Copyright © 2014 Elsevier Ltd. All rights reserved.

Validation of a school-based amblyopia screening protocol in a kindergarten population.

PubMed

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.

Antibody screening by enzyme-linked immunosorbent assay using pooled soluble HLA in renal transplant candidates.

PubMed

Zaer, F; Metz, S; Scornik, J C

1997-01-15

The enzyme-linked immunosorbent assay (ELISA) using HLA class I molecules purified from pooled platelets has the potential to detect HLA antibodies with increased efficiency without sacrificing sensitivity or specificity. This test, which was originally developed in our institution, has been independently validated by recent studies and is now commercially available. We now present evidence of its usefulness as a routine HLA antibody screening test for renal transplant patients. A total of 515 patients were tested monthly by ELISA (13.9 tests/patient) and by antiglobulin-enhanced panel reactivity (6.3 tests/patient). In patients found to be unsensitized, the incidence of false-positive results was less for ELISA than for the panel studies. In patients who were highly sensitized, both tests performed equally well, whereas discordant results were registered mainly in cases of mild sensitization. Because 66% of our patients were not sensitized, the ELISA was effective in reducing the number of more involved tests aimed at characterizing the antibodies. These results provide a foundation to use the pooled platelet HLA ELISA on a routine basis for HLA antibody screening.

The performance of the SEPT9 gene methylation assay and a comparison with other CRC screening tests: A meta-analysis.

PubMed

Song, Lele; Jia, Jia; Peng, Xiumei; Xiao, Wenhua; Li, Yuemin

2017-06-08

The SEPT9 gene methylation assay is the first FDA-approved blood assay for colorectal cancer (CRC) screening. Fecal immunochemical test (FIT), FIT-DNA test and CEA assay are also in vitro diagnostic (IVD) tests used in CRC screening. This meta-analysis aims to review the SEPT9 assay performance and compare it with other IVD CRC screening tests. By searching the Ovid MEDLINE, EMBASE, CBMdisc and CJFD database, 25 out of 180 studies were identified to report the SEPT9 assay performance. 2613 CRC cases and 6030 controls were included, and sensitivity and specificity were used to evaluate its performance at various algorithms. 1/3 algorithm exhibited the best sensitivity while 2/3 and 1/1 algorithm exhibited the best balance between sensitivity and specificity. The performance of the blood SEPT9 assay is superior to that of the serum protein markers and the FIT test in symptomatic population, while appeared to be less potent than FIT and FIT-DNA tests in asymptomatic population. In conclusion, 1/3 algorithm is recommended for CRC screening, and 2/3 or 1/1 algorithms are suitable for early detection for diagnostic purpose. The SEPT9 assay exhibited better performance in symptomatic population than in asymptomatic population.

 The product of triglycerides and glucose as biomarker for screening simple steatosis and NASH in asymptomatic women.

PubMed

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.

[Primary care screening of problems in the elderly and a proposal for a screening protocol with a multidimensional approach].

PubMed

Lino, Valéria Teresa Saraiva; Portela, Margareth Crisóstomo; Camacho, Luiz Antonio Bastos; Rodrigues, Nadia Cristina Pinheiro; Andrade, Monica Kramer de Noronha; O'Dwyer, Gisele

2016-07-21

The objectives were to examine psychometric properties of a screening test for the elderly and to propose a protocol for use in primary care. The method consisted of four stages: (1) inter-evaluator reliability for performance tests and self-assessment questions for eight functions; (2) sensitivity and specificity of questions on depression and social support; (3) meeting of experts to select instrumental activities of daily living (IADL); and (4) elaboration of the protocol. Screening lasted 16 minutes. Inter-evaluator reliability was excellent for performance tests but poor for questions. Depression and social support showed satisfactory sensitivity and specificity (0.74/0.77 and 0.77/0.96). Four IADL were selected by more than 55% of the experts. Following the results, a screening protocol was elaborated that prioritized the use of performance tests, maintaining questions on mood, social support, and IADL. The study suggests better reproducibility of performance tests when compared to questions. For mood and social support, the questions may provide a first screening stage. The proposed protocol allows rapid screening of problems.

Global Sensitivity Analysis of Environmental Models: Convergence, Robustness and Validation

NASA Astrophysics Data System (ADS)

Sarrazin, Fanny; Pianosi, Francesca; Khorashadi Zadeh, Farkhondeh; Van Griensven, Ann; Wagener, Thorsten

2015-04-01

Global Sensitivity Analysis aims to characterize the impact that variations in model input factors (e.g. the parameters) have on the model output (e.g. simulated streamflow). In sampling-based Global Sensitivity Analysis, the sample size has to be chosen carefully in order to obtain reliable sensitivity estimates while spending computational resources efficiently. Furthermore, insensitive parameters are typically identified through the definition of a screening threshold: the theoretical value of their sensitivity index is zero but in a sampling-base framework they regularly take non-zero values. There is little guidance available for these two steps in environmental modelling though. The objective of the present study is to support modellers in making appropriate choices, regarding both sample size and screening threshold, so that a robust sensitivity analysis can be implemented. We performed sensitivity analysis for the parameters of three hydrological models with increasing level of complexity (Hymod, HBV and SWAT), and tested three widely used sensitivity analysis methods (Elementary Effect Test or method of Morris, Regional Sensitivity Analysis, and Variance-Based Sensitivity Analysis). We defined criteria based on a bootstrap approach to assess three different types of convergence: the convergence of the value of the sensitivity indices, of the ranking (the ordering among the parameters) and of the screening (the identification of the insensitive parameters). We investigated the screening threshold through the definition of a validation procedure. The results showed that full convergence of the value of the sensitivity indices is not necessarily needed to rank or to screen the model input factors. Furthermore, typical values of the sample sizes that are reported in the literature can be well below the sample sizes that actually ensure convergence of ranking and screening.

C-reactive protein as a screening test for HIV-associated pulmonary tuberculosis prior to antiretroviral therapy in South Africa.

PubMed

Shapiro, Adrienne E; Hong, Ting; Govere, Sabina; Thulare, Hilary; Moosa, Mahomed-Yunus; Dorasamy, Afton; Wallis, Carole L; Celum, Connie L; Grosset, Jacques; Drain, Paul K

2018-05-28

There is an urgent need for more accurate screening tests for tuberculosis(TB). We assessed the diagnostic accuracy of C-reactive protein (CRP) as a screening test for active TB in HIV-infected ambulatory adults. CRP levels were measured in blood collected at the time of HIV testing.Diagnostic accuracy of CRP for pulmonary TB was calculated (reference standard: TB culture), compared to the WHO 4-symptom screen, consisting of cough, fever, night sweats, and weight loss. Diagnostic accuracy was also calculated for CRP in a larger cohort of HIV-infected adults with a positive symptom screen (reference standard: clinical or microbiological TB). Among 425 HIV-infected outpatients systematically tested for pulmonary TB, TB culture was positive in 42 (10%), 279 (66%) had at least one TB-related symptom and 197 (46%) had a CRP >5 mg/L. The sensitivity of CRP and the TB symptom screen to detect TB was the same (90.5%; 95%CI 77.4-97.3) but specificity of CRP was higher than for the TB symptom screen (58.5% vs. 37.1%, p<0.001). Of persons with no symptoms and normal CRP, 99 (98%) had no TB. In another cohort of 749 patients presenting with at least one TB-related symptom and clinically evaluated, CRP had a sensitivity of 98.7% and specificity of 48.3%. In HIV-infected outpatients, CRP was as sensitive but substantially more specific than TB symptom screening. Use of CRP as a screening tool to exclude active TB could identify the same number of HIV-associated TB cases, but reduce the use of diagnostic sputum testing in TB-endemic regions.

Zagreb Amblyopia Preschool Screening Study: near and distance visual acuity testing increase the diagnostic accuracy of screening for amblyopia.

PubMed

Bušić, Mladen; Bjeloš, Mirjana; Petrovečki, Mladen; Kuzmanović Elabjer, Biljana; Bosnar, Damir; Ramić, Senad; Miletić, Daliborka; Andrijašević, Lidija; Kondža Krstonijević, Edita; Jakovljević, Vid; Bišćan Tvrdi, Ana; Predović, Jurica; Kokot, Antonio; Bišćan, Filip; Kovačević Ljubić, Mirna; Motušić Aras, Ranka

2016-02-01

To present and evaluate a new screening protocol for amblyopia in preschool children. Zagreb Amblyopia Preschool Screening (ZAPS) study protocol performed screening for amblyopia by near and distance visual acuity (VA) testing of 15 648 children aged 48-54 months attending kindergartens in the City of Zagreb County between September 2011 and June 2014 using Lea Symbols in lines test. If VA in either eye was >0.1 logMAR, the child was re-tested, if failed at re-test, the child was referred to comprehensive eye examination at the Eye Clinic. 78.04% of children passed the screening test. Estimated prevalence of amblyopia was 8.08%. Testability, sensitivity, and specificity of the ZAPS study protocol were 99.19%, 100.00%, and 96.68% respectively. The ZAPS study used the most discriminative VA test with optotypes in line as they do not underestimate amblyopia. The estimated prevalence of amblyopia was considerably higher than reported elsewhere. To the best of our knowledge, the ZAPS study protocol reached the highest sensitivity and specificity when evaluating diagnostic accuracy of VA tests for screening. The pass level defined at ≤0.1 logMAR for 4-year-old children, using Lea Symbols in lines missed no amblyopia cases, advocating that both near and distance VA testing should be performed when screening for amblyopia.

Zagreb Amblyopia Preschool Screening Study: near and distance visual acuity testing increase the diagnostic accuracy of screening for amblyopia

PubMed Central

Bušić, Mladen; Bjeloš, Mirjana; Petrovečki, Mladen; Kuzmanović Elabjer, Biljana; Bosnar, Damir; Ramić, Senad; Miletić, Daliborka; Andrijašević, Lidija; Kondža Krstonijević, Edita; Jakovljević, Vid; Bišćan Tvrdi, Ana; Predović, Jurica; Kokot, Antonio; Bišćan, Filip; Kovačević Ljubić, Mirna; Motušić Aras, Ranka

2016-01-01

Aim To present and evaluate a new screening protocol for amblyopia in preschool children. Methods Zagreb Amblyopia Preschool Screening (ZAPS) study protocol performed screening for amblyopia by near and distance visual acuity (VA) testing of 15 648 children aged 48-54 months attending kindergartens in the City of Zagreb County between September 2011 and June 2014 using Lea Symbols in lines test. If VA in either eye was >0.1 logMAR, the child was re-tested, if failed at re-test, the child was referred to comprehensive eye examination at the Eye Clinic. Results 78.04% of children passed the screening test. Estimated prevalence of amblyopia was 8.08%. Testability, sensitivity, and specificity of the ZAPS study protocol were 99.19%, 100.00%, and 96.68% respectively. Conclusion The ZAPS study used the most discriminative VA test with optotypes in lines as they do not underestimate amblyopia. The estimated prevalence of amblyopia was considerably higher than reported elsewhere. To the best of our knowledge, the ZAPS study protocol reached the highest sensitivity and specificity when evaluating diagnostic accuracy of VA tests for screening. The pass level defined at ≤0.1 logMAR for 4-year-old children, using Lea Symbols in lines missed no amblyopia cases, advocating that both near and distance VA testing should be performed when screening for amblyopia. PMID:26935612

[Primary cervical cancer screening].

PubMed

Vargas-Hernández, Víctor Manuel; Vargas-Aguilar, Víctor Manuel; Tovar-Rodríguez, José María

2015-01-01

Cervico-uterine cancer screening with cytology decrease incidence by more than 50%. The cause of this cancer is the human papilloma virus high risk, and requires a sensitive test to provide sufficient sensitivity and specificity for early detection and greater interval period when the results are negative. The test of the human papilloma virus high risk, is effective and safe because of its excellent sensitivity, negative predictive value and optimal reproducibility, especially when combined with liquid-based cytology or biomarkers with viral load, with higher sensitivity and specificity, by reducing false positives for the detection of cervical intraepithelial neoplasia grade 2 or greater injury, with excellent clinical benefits to cervical cancer screening and related infection of human papilloma virus diseases, is currently the best test for early detection infection of human papillomavirus and the risk of carcinogenesis. Copyright © 2015 Academia Mexicana de Cirugía A.C. Published by Masson Doyma México S.A. All rights reserved.

Modeling screening, prevention, and delaying of Alzheimer's disease: an early-stage decision analytic model

PubMed Central

2010-01-01

Background Alzheimer's Disease (AD) affects a growing proportion of the population each year. Novel therapies on the horizon may slow the progress of AD symptoms and avoid cases altogether. Initiating treatment for the underlying pathology of AD would ideally be based on biomarker screening tools identifying pre-symptomatic individuals. Early-stage modeling provides estimates of potential outcomes and informs policy development. Methods A time-to-event (TTE) simulation provided estimates of screening asymptomatic patients in the general population age ≥55 and treatment impact on the number of patients reaching AD. Patients were followed from AD screen until all-cause death. Baseline sensitivity and specificity were 0.87 and 0.78, with treatment on positive screen. Treatment slowed progression by 50%. Events were scheduled using literature-based age-dependent incidences of AD and death. Results The base case results indicated increased AD free years (AD-FYs) through delays in onset and a reduction of 20 AD cases per 1000 screened individuals. Patients completely avoiding AD accounted for 61% of the incremental AD-FYs gained. Total years of treatment per 1000 screened patients was 2,611. The number-needed-to-screen was 51 and the number-needed-to-treat was 12 to avoid one case of AD. One-way sensitivity analysis indicated that duration of screening sensitivity and rescreen interval impact AD-FYs the most. A two-way sensitivity analysis found that for a test with an extended duration of sensitivity (15 years) the number of AD cases avoided was 6,000-7,000 cases for a test with higher sensitivity and specificity (0.90,0.90). Conclusions This study yielded valuable parameter range estimates at an early stage in the study of screening for AD. Analysis identified duration of screening sensitivity as a key variable that may be unavailable from clinical trials. PMID:20433705

Modeling screening, prevention, and delaying of Alzheimer's disease: an early-stage decision analytic model.

PubMed

Furiak, Nicolas M; Klein, Robert W; Kahle-Wrobleski, Kristin; Siemers, Eric R; Sarpong, Eric; Klein, Timothy M

2010-04-30

Alzheimer's Disease (AD) affects a growing proportion of the population each year. Novel therapies on the horizon may slow the progress of AD symptoms and avoid cases altogether. Initiating treatment for the underlying pathology of AD would ideally be based on biomarker screening tools identifying pre-symptomatic individuals. Early-stage modeling provides estimates of potential outcomes and informs policy development. A time-to-event (TTE) simulation provided estimates of screening asymptomatic patients in the general population age > or =55 and treatment impact on the number of patients reaching AD. Patients were followed from AD screen until all-cause death. Baseline sensitivity and specificity were 0.87 and 0.78, with treatment on positive screen. Treatment slowed progression by 50%. Events were scheduled using literature-based age-dependent incidences of AD and death. The base case results indicated increased AD free years (AD-FYs) through delays in onset and a reduction of 20 AD cases per 1000 screened individuals. Patients completely avoiding AD accounted for 61% of the incremental AD-FYs gained. Total years of treatment per 1000 screened patients was 2,611. The number-needed-to-screen was 51 and the number-needed-to-treat was 12 to avoid one case of AD. One-way sensitivity analysis indicated that duration of screening sensitivity and rescreen interval impact AD-FYs the most. A two-way sensitivity analysis found that for a test with an extended duration of sensitivity (15 years) the number of AD cases avoided was 6,000-7,000 cases for a test with higher sensitivity and specificity (0.90,0.90). This study yielded valuable parameter range estimates at an early stage in the study of screening for AD. Analysis identified duration of screening sensitivity as a key variable that may be unavailable from clinical trials.

Improving detection of HIV-associated cognitive impairment: Comparison of the International HIV Dementia Scale and a Brief Screening Battery

PubMed Central

de Almeida, Sergio Monteiro; Kamat, Rujvi; Cherner, Mariana; Umlauf, Anya; Ribeiro, Clea Elisa; de Pereira, Ana Paula; Franklin, Donald; Heaton, Robert K.; Ellis, Ronald J.

2016-01-01

Objectives The International HIV Dementia Scale (IHDS) was developed to screen for HIV-associated dementia (HAD), but it has been used more generally for HIV-associated neurocognitive disorder (HAND). This study sought to examine the accuracy of the IHDS in a cohort of Brazilian HIV-infected individuals and compare its performance to an alternative screening battery for detecting HAND. Methods 108 participants (including 60 HIV-infected persons), completed the IHDS and a gold standard neuropsychological (NP) battery of 17 tests. As alternative screening method, all possible three-test combinations from the NP battery were examined and a superiority index (a marker of specificity and sensitivity) was calculated. Results Sensitivity and specificity to HAND using the standard IHDS cutpoint of 10 were 36% and 75% respectively. The best balance between sensitivity and specificity was accomplished with a modified cutpoint of 11.5, which yielded sensitivity of 72% and specificity of 58%. The top two most sensitive test combinations, compared to the gold standard NP battery, were Trail Making Test A, WAIS-III Digit Symbol (DS) and HVLT-R Total Recall (sensitivity 91%, specificity 96%), and DS, BVMT-R Total Recall and Grooved Pegboard Test-Dominant Hand (sensitivity 94%, specificity 91%). Conclusions Both test combinations can be administered in under 10 minutes and were more accurate than the IHDS in classifying HIV+ participants as NP impaired or unimpaired. These data suggest that demographically corrected T-scores from commonly used NP measures with modest time and material demands can improve identification of patients with HAND who may benefit from a more extensive NP examination. PMID:27828876

[CHALLENGES IN THE DIAGNOSIS OF CUSHING'S SYNDROME IN THE MODERN ERA].

PubMed

Saiegh, Leonard; Sheikh-Ahmad, Mohammad; Reut, Maria; Jubran, Yousef; Shechner, Carmela

2015-12-01

Cushing's syndrome results from prolonged and excessive exposure to medically prescribed corticosteroids, or from excess endogenous cortisol secretion. When endogenous cortisol secretion is suspected, several screening tests are conducted in order to confirm or to rule out the diagnosis. In recent years, as the cut-off point of cortisol concentration on the 1 mg overnight dexamethasone suppression test was lowered, the prevalence of Cushing's syndrome has increased, and more cases of mild syndromes, with negative results on one or more screening tests, have increasingly been reported. In this paper, we will describe the various screening tests used for Cushing's syndrome, and will discuss their degree of sensitivity in the diagnosis of mild cases. We conclude that, in cases of mild syndromes, the sensitivity of some tests appears to be notably lower than has been reported. Until recently, the major challenge has been to distinguish between pseudo-Cushing's states and Cushing's syndrome. Today, however, the challenge has become to avoid misdiagnosis of mild cases, presenting with normal results on some screening tests. The sensitivity of urinary free cortisol seems to be lower than previously reported. Therefore, we recommend not to rely solely on this test in ruling out Cushing's syndrome.

Fecal Immunochemical Test (FIT) for Colon Cancer Screening: Variable Performance with Ambient Temperature

PubMed Central

Doubeni, Chyke A.; Jensen, Christopher D.; Fedewa, Stacey A.; Quinn, Virginia P.; Zauber, Ann G.; Schottinger, Joanne E.; Corley, Douglas A.; Levin, Theodore R.

2017-01-01

Introduction Fecal immunochemical tests (FITs) are widely used in colorectal cancer (CRC) screening, but hemoglobin degradation, due to exposure of the collected sample to high temperatures, could reduce test sensitivity. We examined the relation of ambient temperature exposure with FIT positivity rate and sensitivity. Methods This was a retrospective cohort study of patients 50 to 75 years in Kaiser Permanente Northern California’s CRC screening program, which began mailing FIT kits annually to screen-eligible members in 2007. Primary outcomes were FIT positivity rate and sensitivity to detect CRC. Predictors were month, season, and daily ambient temperatures of test result dates based on US National Oceanic and Atmospheric Administration data. Results Patients (n =472,542) completed 1,141,162 FITs. Weekly test positivity rate ranged from 2.6% to 8.0% (median, 4.4%) and varied significantly by month (June/July vs December/January rate ratio [RR] =0.79, 95% confidence interval [CI], 0.76 to 0.83) and season. FIT sensitivity was lower in June/July (74.5%; 95% CI, 72.5 to 76.6) than January/December (78.9%; 95% CI, 77.0 to 80.7). Conclusions FITs completed during high ambient temperatures had lower positivity rates and lower sensitivity. Changing kit design, specimen transportation practices, or avoiding periods of high ambient temperatures may help optimize FIT performance, but may also increase testing complexity and reduce patient adherence, requiring careful study. PMID:28076249

Point-of-care urine tests for smoking status and isoniazid treatment monitoring in adult patients.

PubMed

Nicolau, Ioana; Tian, Lulu; Menzies, Dick; Ostiguy, Gaston; Pai, Madhukar

2012-01-01

Poor adherence to isoniazid (INH) preventive therapy (IPT) is an impediment to effective control of latent tuberculosis (TB) infection. TB patients who smoke are at higher risk of latent TB infection, active disease, and TB mortality, and may have lower adherence to their TB medications. The objective of our study was to validate IsoScreen and SmokeScreen (GFC Diagnostics, UK), two point-of-care tests for monitoring INH intake and determining smoking status. The tests could be used together in the same individual to help identify patients with a high-risk profile and provide a tailored treatment plan that includes medication management, adherence interventions, and smoking cessation programs. 200 adult outpatients attending the TB and/or the smoking cessation clinic were recruited at the Montreal Chest Institute. Sensitivity and specificity were measured for each test against the corresponding composite reference standard. Test reliability was measured using kappa statistic for intra-rater and inter-rater agreement. Univariate and multivariate logistic regression models were used to explore possible covariates that might be related to false-positive and false-negative test results. IsoScreen had a sensitivity of 93.2% (95% confidence interval [CI] 80.3, 98.2) and specificity of 98.7% (94.8, 99.8). IsoScreen had intra-rater agreement (kappa) of 0.75 (0.48, 0.94) and inter-rater agreement of 0.61 (0.27, 0.90). SmokeScreen had a sensitivity of 69.2% (56.4, 79.8), specificity of 81.6% (73.0, 88.0), intra-rater agreement of 0.77 (0.56, 0.94), and inter-rater agreement of 0.66 (0.42, 0.88). False-positive SmokeScreen tests were strongly associated with INH treatment. IsoScreen had high validity and reliability, whereas SmokeScreen had modest validity and reliability. SmokeScreen tests did not perform well in a population receiving INH due to the association between INH treatment and false-positive SmokeScreen test results. Development of the next generation SmokeScreen assay should account for this potential interference.

Point-of-Care Urine Tests for Smoking Status and Isoniazid Treatment Monitoring in Adult Patients

PubMed Central

Nicolau, Ioana; Tian, Lulu; Menzies, Dick; Ostiguy, Gaston; Pai, Madhukar

2012-01-01

Background Poor adherence to isoniazid (INH) preventive therapy (IPT) is an impediment to effective control of latent tuberculosis (TB) infection. TB patients who smoke are at higher risk of latent TB infection, active disease, and TB mortality, and may have lower adherence to their TB medications. The objective of our study was to validate IsoScreen and SmokeScreen (GFC Diagnostics, UK), two point-of-care tests for monitoring INH intake and determining smoking status. The tests could be used together in the same individual to help identify patients with a high-risk profile and provide a tailored treatment plan that includes medication management, adherence interventions, and smoking cessation programs. Methodology/Principal Findings 200 adult outpatients attending the TB and/or the smoking cessation clinic were recruited at the Montreal Chest Institute. Sensitivity and specificity were measured for each test against the corresponding composite reference standard. Test reliability was measured using kappa statistic for intra-rater and inter-rater agreement. Univariate and multivariate logistic regression models were used to explore possible covariates that might be related to false-positive and false-negative test results. IsoScreen had a sensitivity of 93.2% (95% confidence interval [CI] 80.3, 98.2) and specificity of 98.7% (94.8, 99.8). IsoScreen had intra-rater agreement (kappa) of 0.75 (0.48, 0.94) and inter-rater agreement of 0.61 (0.27, 0.90). SmokeScreen had a sensitivity of 69.2% (56.4, 79.8), specificity of 81.6% (73.0, 88.0), intra-rater agreement of 0.77 (0.56, 0.94), and inter-rater agreement of 0.66 (0.42, 0.88). False-positive SmokeScreen tests were strongly associated with INH treatment. Conclusions IsoScreen had high validity and reliability, whereas SmokeScreen had modest validity and reliability. SmokeScreen tests did not perform well in a population receiving INH due to the association between INH treatment and false-positive SmokeScreen test results. Development of the next generation SmokeScreen assay should account for this potential interference. PMID:23029310

Sensitivity and specificity of Addenbrooke's Cognitive Examination, Mattis Dementia Rating Scale, Frontal Assessment Battery and Mini Mental State Examination for diagnosing dementia in Parkinson's disease.

PubMed

Kaszás, B; Kovács, N; Balás, I; Kállai, J; Aschermann, Z; Kerekes, Z; Komoly, S; Nagy, F; Janszky, J; Lucza, T; Karádi, K

2012-06-01

Among the non-motor features of Parkinson's disease (PD), cognitive impairment is one of the most troublesome problems. Highly sensitive and specific screening instruments for detecting dementia in PD (PDD) are required in the clinical practice. In our study we evaluated the sensitivity and specificity of different neuropsychological tests (Addenbrooke's Cognitive Examination, ACE; Frontal Assessment Battery, FAB and Mattis Dementia Rating Scale, MDRS) in 73 Parkinson's disease patients without depression. By receiver operating characteristic curve analysis, these screening instruments were tested against the recently established clinical diagnostic criteria of PDD. Best cut-off score for ACE to identify PDD was 80 points (sensitivity = 74.0%, specificity = 78.1%). For FAB the most optimal cut-off value was 12 points (sensitivity = 66.3%, specificity = 72.2%); whereas for MDRS it was 125 points (sensitivity = 89.8%, specificity = 98.3%). Among the examined test batteries, MDRS had the best clinicometric profile for detecting PDD. Although the types of applied screening instruments might differ from movement disorder clinic to clinic within a country, determination of the most specific and sensitive test for the given population remains to be an important task. Our results demonstrated that the specificity and sensitivity of MDRS was better than those of ACE, FAB and MMSE in Hungary. However, further studies with larger sample size and more uniform criteria for participation are required to determine the most suitable screening instrument for cognitive impairment. Copyright © 2012 Elsevier Ltd. All rights reserved.

Radiographers supporting radiologists in the interpretation of screening mammography: a viable strategy to meet the shortage in the number of radiologists.

PubMed

Torres-Mejía, Gabriela; Smith, Robert A; Carranza-Flores, María de la Luz; Bogart, Andy; Martínez-Matsushita, Louis; Miglioretti, Diana L; Kerlikowske, Karla; Ortega-Olvera, Carolina; Montemayor-Varela, Ernesto; Angeles-Llerenas, Angélica; Bautista-Arredondo, Sergio; Sánchez-González, Gilberto; Martínez-Montañez, Olga G; Uscanga-Sánchez, Santos R; Lazcano-Ponce, Eduardo; Hernández-Ávila, Mauricio

2015-05-16

An alternative approach to the traditional model of radiologists interpreting screening mammography is necessary due to the shortage of radiologists to interpret screening mammograms in many countries. We evaluated the performance of 15 Mexican radiographers, also known as radiologic technologists, in the interpretation of screening mammography after a 6 months training period in a screening setting. Fifteen radiographers received 6 months standardized training with radiologists in the interpretation of screening mammography using the Breast Imaging Reporting and Data System (BI-RADS) system. A challenging test set of 110 cases developed by the Breast Cancer Surveillance Consortium was used to evaluate their performance. We estimated sensitivity, specificity, false positive rates, likelihood ratio of a positive test (LR+) and the area under the subject-specific Receiver Operating Characteristic (ROC) curve (AUC) for diagnostic accuracy. A mathematical model simulating the consequences in costs and performance of two hypothetical scenarios compared to the status quo in which a radiologist reads all screening mammograms was also performed. Radiographer's sensitivity was comparable to the sensitivity scores achieved by U.S. radiologists who took the test but their false-positive rate was higher. Median sensitivity was 73.3 % (Interquartile range, IQR: 46.7-86.7 %) and the median false positive rate was 49.5 % (IQR: 34.7-57.9 %). The median LR+ was 1.4 (IQR: 1.3-1.7 %) and the median AUC was 0.6 (IQR: 0.6-0.7). A scenario in which a radiographer reads all mammograms first, and a radiologist reads only those that were difficult for the radiographer, was more cost-effective than a scenario in which either the radiographer or radiologist reads all mammograms. Given the comparable sensitivity achieved by Mexican radiographers and U.S. radiologists on a test set, screening mammography interpretation by radiographers appears to be a possible adjunct to radiologists in countries with shortages of radiologists. Further studies are required to assess the effectiveness of different training programs in order to obtain acceptable screening accuracy, as well as the best approaches for the use of non-physician readers to interpret screening mammography.

Detection of CIN by naked eye visualization after application of acetic acid.

PubMed

Londhe, M; George, S S; Seshadri, L

1997-06-01

A prospective study was undertaken to determine the sensitivity and specificity of acetic application to the cervix followed by naked eye visualization as a screening test for detection of cervical intraepithelial neoplasia. Three hundred and seventy two sexually active woman in the reproductive age group were studied. All the women underwent Papanicolaou test, acetic acid test and colposcopy. One hundred and seventy five woman were acetic acid test negative, 197 women were acetic acid test positive. The sensitivity of acetic acid test was 72.4%, specificity 54% and false negative rate 15.2%, as compared to papanicolaou test which had a sensitivity of 13.2%, specificity of 96.3% and false negative rate of 24.4%. The advantage of the acetic acid test lies in its easy technique, low cost and high sensitivity which are important factors for determining the efficacy of any screening programme in developing countries.

Pooled analysis of the accuracy of five cervical cancer screening tests assessed in eleven studies in Africa and India.

PubMed

Arbyn, Marc; Sankaranarayanan, Rengaswamy; Muwonge, Richard; Keita, Namory; Dolo, Amadou; Mbalawa, Charles Gombe; Nouhou, Hassan; Sakande, Boblewende; Wesley, Ramani; Somanathan, Thara; Sharma, Anjali; Shastri, Surendra; Basu, Parthasarathy

2008-07-01

Cervical cancer is the main cancer among women in sub-Saharan Africa, India and other parts of the developing world. Evaluation of screening performance of effective, feasible and affordable early detection and management methods is a public health priority. Five screening methods, naked eye visual inspection of the cervix uteri after application of diluted acetic acid (VIA), or Lugol's iodine (VILI) or with a magnifying device (VIAM), the Pap smear and human papillomavirus testing with the high-risk probe of the Hybrid Capture-2 assay (HC2), were evaluated in 11 studies in India and Africa. More than 58,000 women, aged 25-64 years, were tested with 2-5 screening tests and outcome verification was done on all women independent of the screen test results. The outcome was presence or absence of cervical intraepithelial neoplasia (CIN) of different degrees or invasive cervical cancer. Verification was based on colposcopy and histological interpretation of colposcopy-directed biopsies. Negative colposcopy was accepted as a truly negative outcome. VIA showed a sensitivity of 79% (95% CI 73-85%) and 83% (95% CI 77-89%), and a specificity of 85% (95% CI 81-89%) and 84% (95% CI 80-88%) for the outcomes CIN2+ or CIN3+, respectively. VILI was on average 10% more sensitive and equally specific. VIAM showed similar results as VIA. The Pap smear showed lowest sensitivity, even at the lowest cutoff of atypical squamous cells of undetermined significance (57%; 95% CI 38-76%) for CIN2+ but the specificity was rather high (93%; 95% CI 89-97%). The HC2-assay showed a sensitivity for CIN2+ of 62% (95% CI 56-68%) and a specificity of 94% (95% CI 92-95%). Substantial interstudy variation was observed in the accuracy of the visual screening methods. Accuracy of visual methods and cytology increased over time, whereas performance of HC2 was constant. Results of visual tests and colposcopy were highly correlated. This study was the largest ever done that evaluates the cross-sectional accuracy of screening tests for cervical cancer precursors in developing countries. The merit of the study was that all screened subjects were submitted to confirmatory investigations avoiding to verification bias. A major finding was the consistently higher sensitivity but equal specificity of VILI compared with VIA. Nevertheless, some caution is warranted in the interpretation of observed accuracy measures, since a certain degree of gold standard misclassification cannot be excluded. Because of the correlation between visual screening tests and colposcopy and a certain degree of over-diagnosis of apparent CIN2+ by study pathologists, it is possible that both sensitivity and specificity of VIA and VILI were overestimated. Gold standard verification error could also explain the surprisingly low sensitivity of HC2, which contrasts with findings from other studies. (c) 2008 Wiley-Liss, Inc.

Colon cancer screening: which non-invasive filter tests?

PubMed

Pox, Christian

2011-01-01

The following non-invasive stool tests for colorectal cancer (CRC) screening exist: guaiac or immunochemical fecal occult blood testing (FOBT), genetic stool tests and the M2-PK. Currently the most widely used tests are guaiac-based (gFOBT). Several randomized controlled trials have shown that gFOBT are able to achieve a reduction in CRC-related mortality. This reduction is achieved by detecting asymptomatic cancers at an early stage with a better prognosis. However, gFOBT have a low sensitivity for colorectal adenomas and are thus unlikely to be able to reduce the incidence of CRC. Furthermore, gFOBT are not specific for human blood and can be influenced by external factors. Immunochemical tests (iFOBT) only detect human blood in the stool. In two recent randomized studies from the Netherlands comparing guaiac and immunochemical tests in the asymptomatic population, iFOBT were found to detect more cancers than gFOBT. Furthermore, iFOBT were able to detect more advanced adenomas thus having the potential to be able to reduce the incidence of CRC as well as CRC-related mortality. In the recently released European CRC screening guidelines, iFOBT are considered the screening test of choice. Several questions remain however. It is currently unknown what the optimal cut-off value for an iFOBT to be considered positive should be and what the number of stool samples is that are required. Genetic stool tests detect mutations in stool that can be found in CRC. The original test testing for 21 genetic changes was found to be superior to gFOBT for the detection of cancers. However, the sensitivity was moderate (51.6%) and the sensitivity for advanced adenomas was low. In the meantime the test has been modified improving DNA extraction and reducing the number of mutations tested for as well as including a methylation marker. The efficacy of the modified test in the screening population is unknown. M2-PK is an isomer of the enzyme pyruvate kinase that is involved in glycolysis. Studies have found a good sensitivity for cancers, a low sensitivity for advanced adenomas with a specificity of around 80%. Further studies in the screening population are required. Copyright © 2011 S. Karger AG, Basel.

Utility of quantitative sensory testing and screening tools in identifying HIV-associated peripheral neuropathy in Western Kenya: pilot testing.

PubMed

Cettomai, Deanna; Kwasa, Judith; Kendi, Caroline; Birbeck, Gretchen L; Price, Richard W; Bukusi, Elizabeth A; Cohen, Craig R; Meyer, Ana-Claire

2010-12-08

Neuropathy is the most common neurologic complication of HIV but is widely under-diagnosed in resource-constrained settings. We aimed to identify tools that accurately distinguish individuals with moderate/severe peripheral neuropathy and can be administered by non-physician healthcare workers (HCW) in resource-constrained settings. We enrolled a convenience sample of 30 HIV-infected outpatients from a Kenyan HIV-care clinic. A HCW administered the Neuropathy Severity Score (NSS), Single Question Neuropathy Screen (Single-QNS), Subjective Peripheral Neuropathy Screen (Subjective-PNS), and Brief Peripheral Neuropathy Screen (Brief-PNS). Monofilament, graduated tuning fork, and two-point discrimination examinations were performed. Tools were validated against a neurologist's clinical assessment of moderate/severe neuropathy. The sample was 57% male, mean age 38.6 years, and mean CD4 count 324 cells/µL. Neurologist's assessment identified 20% (6/30) with moderate/severe neuropathy. Diagnostic utilities for moderate/severe neuropathy were: Single-QNS--83% sensitivity, 71% specificity; Subjective-PNS-total--83% sensitivity, 83% specificity; Subjective-PNS-max and NSS--67% sensitivity, 92% specificity; Brief-PNS--0% sensitivity, 92% specificity; monofilament--100% sensitivity, 88% specificity; graduated tuning fork--83% sensitivity, 88% specificity; two-point discrimination--75% sensitivity, 58% specificity. Pilot testing suggests Single-QNS, Subjective-PNS, and monofilament examination accurately identify HIV-infected patients with moderate/severe neuropathy and may be useful diagnostic tools in resource-constrained settings.

Sensitivity of some tests for alcohol abuse : findings in nonalcoholics recovering from intoxication.

DOT National Transportation Integrated Search

1983-01-01

A variety of measurements are sensitive to alcoholism; some may be applicable to screening programs, but more precise knowledge of sensitivity and specificity would help to select a minimal test battery. This study assessed the sensitivity of some te...

A laboratory and field evaluation of a portable immunoassay test for triazine herbicides in environmental water samples

USGS Publications Warehouse

Schulze, P.A.; Capel, P.D.; Squillace, P.J.; Helsel, D.R.

1993-01-01

The usefulness and sensitivity, of a portable immunoassay test for the semiquantitative field screening of water samples was evaluated by means of laboratory and field studies. Laboratory results indicated that the tests were useful for the determination of atrazine concentrations of 0.1 to 1.5 μg/L. At a concentration of 1 μg/L, the relative standard deviation in the difference between the regression line and the actual result was about 40 percent. The immunoassay was less sensitive and produced similar errors for other triazine herbicides. After standardization, the test results were relatively insensitive to ionic content and variations in pH (range, 4 to 10), mildly sensitive to temperature changes, and quite sensitive to the timing of the final incubation step, variances in timing can be a significant source of error. Almost all of the immunoassays predicted a higher atrazine concentration in water samples when compared to results of gas chromatography. If these tests are used as a semiquantitative screening tool, this tendency for overprediction does not diminish the tests' usefulness. Generally, the tests seem to be a valuable method for screening water samples for triazine herbicides.

Development of new non-invasive tests for colorectal cancer screening: the relevance of information on adenoma detection.

PubMed

Haug, Ulrike; Knudsen, Amy B; Lansdorp-Vogelaar, Iris; Kuntz, Karen M

2015-06-15

Researchers are actively pursuing the development of a new non-invasive test (NIT) for colorectal cancer (CRC) screening as an alternative to fecal occult blood tests (FOBTs). The majority of pilot studies focus on the detection of invasive CRC rather than precursor lesions (i.e., adenomas). We aimed to explore the relevance of adenoma detection for the viability of an NIT for CRC screening by considering a hypothetical test that does not detect adenomas beyond chance. We used the Simulation Model of Colorectal Cancer (SimCRC) to estimate the effectiveness of CRC screening and the lifetime costs (payers' perspective) for a cohort of US 50-years-old persons to whom CRC screening is offered from age 50-75. We compared annual screening with guaiac and immunochemical FOBTs (with sensitivities up to 70 and 24% for CRC and adenomas, respectively) to annual screening with a hypothetical NIT (sensitivity of 90% for CRC, no detection of adenomas beyond chance, specificity and cost similar to FOBTs). Screening with the NIT was not more effective, but was 29-44% more costly than screening with FOBTs. The findings were robust to varying the screening interval, the NIT's sensitivity for CRC, adherence rates favoring the NIT, and the NIT's unit cost. A comparative modelling approach using a model that assumes a shorter adenoma dwell time (MISCAN-COLON) confirmed the superiority of the immunochemical FOBT over an NIT with no ability to detect adenomas. Information on adenoma detection is crucial to determine whether a new NIT is a viable alternative to FOBTs for CRC screening. Current evidence thus lacks an important piece of information to identify marker candidates that hold real promise and deserve further (large-scale) evaluation. © 2014 UICC.

Demand for Colonoscopy in Colorectal Cancer Screening Using a Quantitative Fecal Immunochemical Test and Age/Sex-Specific Thresholds for Test Positivity.

PubMed

Chen, Sam Li-Sheng; Hsu, Chen-Yang; Yen, Amy Ming-Fang; Young, Graeme P; Chiu, Sherry Yueh-Hsia; Fann, Jean Ching-Yuan; Lee, Yi-Chia; Chiu, Han-Mo; Chiou, Shu-Ti; Chen, Hsiu-Hsi

2018-06-01

Background: Despite age and sex differences in fecal hemoglobin (f-Hb) concentrations, most fecal immunochemical test (FIT) screening programs use population-average cut-points for test positivity. The impact of age/sex-specific threshold on FIT accuracy and colonoscopy demand for colorectal cancer screening are unknown. Methods: Using data from 723,113 participants enrolled in a Taiwanese population-based colorectal cancer screening with single FIT between 2004 and 2009, sensitivity and specificity were estimated for various f-Hb thresholds for test positivity. This included estimates based on a "universal" threshold, receiver-operating-characteristic curve-derived threshold, targeted sensitivity, targeted false-positive rate, and a colonoscopy-capacity-adjusted method integrating colonoscopy workload with and without age/sex adjustments. Results: Optimal age/sex-specific thresholds were found to be equal to or lower than the universal 20 μg Hb/g threshold. For older males, a higher threshold (24 μg Hb/g) was identified using a 5% false-positive rate. Importantly, a nonlinear relationship was observed between sensitivity and colonoscopy workload with workload rising disproportionately to sensitivity at 16 μg Hb/g. At this "colonoscopy-capacity-adjusted" threshold, the test positivity (colonoscopy workload) was 4.67% and sensitivity was 79.5%, compared with a lower 4.0% workload and a lower 78.7% sensitivity using 20 μg Hb/g. When constrained on capacity, age/sex-adjusted estimates were generally lower. However, optimizing age/-sex-adjusted thresholds increased colonoscopy demand across models by 17% or greater compared with a universal threshold. Conclusions: Age/sex-specific thresholds improve FIT accuracy with modest increases in colonoscopy demand. Impact: Colonoscopy-capacity-adjusted and age/sex-specific f-Hb thresholds may be useful in optimizing individual screening programs based on detection accuracy, population characteristics, and clinical capacity. Cancer Epidemiol Biomarkers Prev; 27(6); 704-9. ©2018 AACR . ©2018 American Association for Cancer Research.

Evaluation of Hydroxyatrazine in the Endocrine Disruptor Screening and Testing Program’s Male and Female Pubertal Protocols.

EPA Science Inventory

Evaluation of Hydroxyatrazine in the Endocrine Disruptor Screening and Testing Program’s Male and Female Pubertal Protocols. ABSTRACT Two critical components of the validation of any in vivo screening assay are to demonstrate sensitivity (ability to detect weak endocrine ...

The Sensitivity of Adolescent School-Based Hearing Screens Is Significantly Improved by Adding High Frequencies

ERIC Educational Resources Information Center

Sekhar, Deepa L.; Zalewski, Thomas R.; Beiler, Jessica S.; Czarnecki, Beth; Barr, Ashley L.; King, Tonya S.; Paul, Ian M.

2016-01-01

High frequency hearing loss (HFHL), often related to hazardous noise, affects one in six U.S. adolescents. Yet, only 20 states include school-based hearing screens for adolescents. Only six states test multiple high frequencies. Study objectives were to (1) compare the sensitivity of state school-based hearing screens for adolescents to gold…

Testing the tests--an empirical evaluation of screening tests for the detection of cognitive impairment in aviators.

PubMed

Stokes, A F; Banich, M T; Elledge, V C

1991-08-01

The FAA has expressed concern that flight safety could be compromised by undetected cognitive impairment in pilots due to conditions such as substance abuse, mental illness, and neuropsychological problems. Interest has been shown in the possibility of adding a brief "mini-mental exam," or a simple automated test-battery to the standard flight medical to screen for such conditions. The research reported here involved the empirical evaluation of two "mini-mental exams," two paper-and-pencil test batteries, and a prototype version of an automated screening battery. Sensitivity, specificity, and positive predictive value were calculated for each sub-task in a discriminant study of 54 pilots and 62 individuals from a heterogeneous clinical population. Results suggest that the "mini-mental exams" are poor candidates for a screening test. The automated battery showed the best discrimination performance, in part because of the incorporation of dual-task tests of divided attention performance. These tests appear to be particularly sensitive to otherwise difficult-to-detect cognitive impairments of a mild or subtle nature. The use of an automated battery of tests as a screening instrument does appear to be feasible in principle, but the practical success of a screening program is heavily dependent upon the actual prevalence of cognitive impairment in the medical applicant population.

Contributions and Limitations of National Cervical Cancer Screening Program in Korea: A Retrospective Observational Study.

PubMed

Lee, Jung Hyun; Kim, Hyeongsu; Choi, Heejung; Jeong, Hyoseon; Ko, Young; Shim, Seung-Hyuk; Lee, Eunjoo; Chae, Su Hyun

2018-03-01

The purpose of this study was to evaluate the contributions and limitations of the cervical cancer screening test with accuracy in Korea. This was a retrospective observational study. The study population consisted of all participants who underwent cervical cancer screening test from 2009 to 2014. The data were obtained from National Health Information Database (NHID) which represents medical use records of most Koreans. As the indices for contributions and limitations of the screening test, crude detection rate, incidence rate of interval cancer, sensitivity, specificity, and positive predictive value were used. The crude detection rate of screening test per 100,000 participants increased from 100.7 in 2009 to 102.1 in 2014. The incidence rate of interval cancer per 100,000 negatives decreased from 13.0 in 2009 to 10.2 in 2014. The sensitivities of screening test were 88.7% in 2009 and 91.2% in 2014, and the specificities were 98.5% in 2009 and 97.7% in 2014. The positive predictive value of screening decreased from 6.2% in 2009 to 4.3% in 2014. The Korean national cervical cancer screening program has improved in accuracy and has contributed to detection of early stage of cervical cancer over the years. Along with efforts to promote participation in cancer screening programs, quality control over the screening program should be enhanced. Copyright © 2018. Published by Elsevier B.V.

Illustrating economic evaluation of diagnostic technologies: comparing Helicobacter pylori screening strategies in prevention of gastric cancer in Canada.

PubMed

Xie, Feng; O'Reilly, Daria; Ferrusi, Ilia L; Blackhouse, Gord; Bowen, James M; Tarride, Jean-Eric; Goeree, Ron

2009-05-01

The aim of this paper is to present an economic evaluation of diagnostic technologies using Helicobacter pylori screening strategies for the prevention of gastric cancer as an illustration. A Markov model was constructed to compare the lifetime cost and effectiveness of 4 potential strategies: no screening, the serology test by enzyme-linked immunosorbent assay (ELISA), the stool antigen test (SAT), and the (13)C-urea breath test (UBT) for the detection of H. pylori among a hypothetical cohort of 10,000 Canadian men aged 35 years. Special parameter consideration included the sensitivity and specificity of each screening strategy, which determined the model structure and treatment regimen. The primary outcome measured was the incremental cost-effectiveness ratio between the screening strategies and the no-screening strategy. Base-case analysis and probabilistic sensitivity analysis were performed using the point estimates of the parameters and Monte Carlo simulations, respectively. Compared with the no-screening strategy in the base-case analysis, the incremental cost-effectiveness ratio was $33,000 per quality-adjusted life-year (QALY) for the ELISA, $29,800 per QALY for the SAT, and $50,400 per QALY for the UBT. The probabilistic sensitivity analysis revealed that the no-screening strategy was more cost effective if the willingness to pay (WTP) was <$20,000 per QALY, while the SAT had the highest probability of being cost effective if the WTP was >$30,000 per QALY. Both the ELISA and the UBT were not cost-effective strategies over a wide range of WTP values. Although the UBT had the highest sensitivity and specificity, either no screening or the SAT could be the most cost-effective strategy depending on the WTP threshold values from an economic perspective. This highlights the importance of economic evaluations of diagnostic technologies.

Methicillin-Resistant Staphylococcus aureus: Comparison of Susceptibility Testing Methods and Analysis of mecA-Positive Susceptible Strains

PubMed Central

Sakoulas, George; Gold, Howard S.; Venkataraman, Lata; DeGirolami, Paola C.; Eliopoulos, George M.; Qian, Qinfang

2001-01-01

Methicillin-resistant Staphylococcus aureus (MRSA) is responsible for an increasing number of serious nosocomial and community-acquired infections. Phenotypic heterogeneous drug resistance (heteroresistance) to antistaphylococcal beta-lactams affects the results of susceptibility testing. The present study compared the MRSA-Screen latex agglutination test (Denka Seiken Co., Ltd., Tokyo, Japan) for detection of PBP 2a with agar dilution, the VITEK-1 and VITEK-2 systems (bioMérieux, St. Louis, Mo.), and the oxacillin agar screen test for detection of MRSA, with PCR for the mecA gene used as the “gold standard” assay. Analysis of 107 methicillin-susceptible S. aureus (MSSA) isolates and 203 MRSA isolates revealed that the MRSA-Screen latex agglutination test is superior to any single phenotype-based susceptibility testing method, with a sensitivity of 100% and a specificity of 99.1%. Only one isolate that lacked mecA was weakly positive by the MRSA-Screen latex agglutination test. This isolate was phenotypically susceptible to oxacillin and did not contain the mecA gene by Southern blot hybridization. The oxacillin agar screen test, the VITEK-1 system, the VITEK-2 system, and agar dilution showed sensitivities of 99.0, 99.0, 99.5, and 99%, respectively, and specificities of 98.1, 100, 97.2, and 100%, respectively. The differences in sensitivity or specificity were not statistically significant. Oxacillin bactericidal assays showed that mecA- and PBP 2a-positive S. aureus isolates that are susceptible to antistaphylococcal beta-lactams by conventional methods are functionally resistant to oxacillin. We conclude that the accuracy of the MRSA-Screen latex agglutination method for detection of PBP 2a approaches the accuracy of PCR and is more accurate than any susceptibility testing method used alone for the detection of MRSA. PMID:11682512

Effectiveness of rapid prescreening and 10% rescreening in liquid-based Papanicolaou testing.

PubMed

Currens, Heather S; Nejkauf, Katharine; Wagner, Lynn; Raab, Stephen S

2012-01-01

Although rapid prescreening (RPS) has been shown to be an effective quality control procedure for detecting false-negative conventional Papanicolaou (Pap) tests, RPS has not been widely implemented in the United States. In our laboratory, cytotechnologists performed RPS in 3,567 liquid-based Pap tests: 1,911 SurePath (BD Diagnostics-TriPath, Burlington, NC) preparations that were manually screened and 1,656 ThinPrep Pap tests (Hologic, Bedford, MA) that were imaged using the ThinPrep Imaging System (Hologic). We compared the sensitivity of RPS, 10% rescreening (R-10%), and routine screening (RS). In contrast with previously published findings, we found that RS + RPS did not improve screening sensitivity compared with RS + R-10%. These results support the following hypotheses: (1) Higher baseline RS sensitivity as a result of Pap test diagnoses standardization implemented for quality improvement purposes decreases the performance impact of RPS. (2) R-10% and RPS quality assurance methods detect diagnostic failures caused by different types of cognitive errors.

Prospective evaluation of methylated SEPT9 in plasma for detection of asymptomatic colorectal cancer

PubMed Central

Church, Timothy Robert; Wandell, Michael; Lofton-Day, Catherine; Mongin, Steven J; Burger, Matthias; Payne, Shannon R; Castaños-Vélez, Esmeralda; Blumenstein, Brent A; Rösch, Thomas; Osborn, Neal; Snover, Dale; Day, Robert W; Ransohoff, David F

2014-01-01

Background As screening methods for colorectal cancer (CRC) are limited by uptake and adherence, further options are sought. A blood test might increase both, but none has yet been tested in a screening setting. Objective We prospectively assessed the accuracy of circulating methylated SEPT9 DNA (mSEPT9) for detecting CRC in a screening population. Design Asymptomatic individuals ≥50 years old scheduled for screening colonoscopy at 32 US and German clinics voluntarily gave blood plasma samples before colon preparation. Using a commercially available assay, three independent blinded laboratories assayed plasma DNA of all CRC cases and a stratified random sample of other subjects in duplicate real time PCRs. The primary outcomes measures were standardised for overall sensitivity and specificity estimates. Results 7941 men (45%) and women (55%), mean age 60 years, enrolled. Results from 53 CRC cases and from 1457 subjects without CRC yielded a standardised sensitivity of 48.2% (95% CI 32.4% to 63.6%; crude rate 50.9%); for CRC stages I–IV, values were 35.0%, 63.0%, 46.0% and 77.4%, respectively. Specificity was 91.5% (95% CI 89.7% to 93.1%; crude rate 91.4%). Sensitivity for advanced adenomas was low (11.2%). Conclusions Our study using the blood based mSEPT9 test showed that CRC signal in blood can be detected in asymptomatic average risk individuals undergoing screening. However, the utility of the test for population screening for CRC will require improved sensitivity for detection of early cancers and advanced adenomas. Clinical Trial Registration Number: NCT00855348 PMID:23408352

Rapid biochemical screening for Salmonella, Shigella, Yersinia, and Aeromonas isolates from stool specimens.

PubMed Central

De Ryck, R; Struelens, M J; Serruys, E

1994-01-01

Four screens for the rapid (4 to 6 h) biochemical detection of pathogens from enteric isolation media are described. The Salmonella screen consisted of Kligler iron agar (KIA), motility-indole-urea-tryptophan-deamination semisolid medium (MIU-TDA), and the o-nitrophenyl-beta-D-galactopyranoside (ONPG) test; the Shigella screen consisted of KIA, MIU-TDA, the ONPG test, and the lysine decarboxylation-indole test; the Yersinia screen consisted of a rhamnose broth; the Aeromonas screen consisted of a xylose agar plate. When tested on 2,102 fresh isolates and 71 stock strains, the screens correctly detected 212 enteric pathogens (sensitivity, 100%), with a specificity of 98.1%. PMID:8077408

Single measure and gated screening approaches for identifying students at-risk for academic problems: Implications for sensitivity and specificity.

PubMed

Van Norman, Ethan R; Nelson, Peter M; Klingbeil, David A

2017-09-01

Educators need recommendations to improve screening practices without limiting students' instructional opportunities. Repurposing previous years' state test scores has shown promise in identifying at-risk students within multitiered systems of support. However, researchers have not directly compared the diagnostic accuracy of previous years' state test scores with data collected during fall screening periods to identify at-risk students. In addition, the benefit of using previous state test scores in conjunction with data from a separate measure to identify at-risk students has not been explored. The diagnostic accuracy of 3 types of screening approaches were tested to predict proficiency on end-of-year high-stakes assessments: state test data obtained during the previous year, data from a different measure administered in the fall, and both measures combined (i.e., a gated model). Extant reading and math data (N = 2,996) from 10 schools in the Midwest were analyzed. When used alone, both measures yielded similar sensitivity and specificity values. The gated model yielded superior specificity values compared with using either measure alone, at the expense of sensitivity. Implications, limitations, and ideas for future research are discussed. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Test performance of immunologic fecal occult blood testing and sigmoidoscopy compared with primary colonoscopy screening for colorectal advanced adenomas.

PubMed

Khalid-de Bakker, Carolina A J; Jonkers, Daisy M A E; Sanduleanu, Silvia; de Bruïne, Adriaan P; Meijer, Gerrit A; Janssen, Jan B M J; van Engeland, Manon; Stockbrügger, Reinhold W; Masclee, Ad A M

2011-10-01

Given the current increase in colorectal cancer screening, information on performance of screening tests is needed, especially in groups with a presumed lower test performance. We compared test performance of immunologic fecal occult blood testing (FIT) and pseudosigmoidoscopy with colonoscopy for detection of advanced adenomas in an average risk screening population. In addition, we explored the influence of gender, age, and location on test performance. FIT was collected prior to colonoscopy with a 50 ng/mL cutoff point. FIT results and complete colonoscopy findings were available from 329 subjects (mean age: 54.6 ± 3.7 years, 58.4% women). Advanced adenomas were detected in 38 (11.6%) of 329 subjects. Sensitivity for advanced adenomas of FIT and sigmoidoscopy were 15.8% (95% CI: 6.0-31.3) and 73.7% (95% CI: 56.9-86.6), respectively. No sensitivity improvement was obtained using the combination of sigmoidoscopy and FIT. Mean fecal hemoglobin in FIT positives was significantly lower for participants with only proximal adenomas versus those with distal ones (P = 0.008), for women versus men (P = 0.023), and for younger (<55 years) versus older (≥55 years) subjects (P = 0.029). Sensitivities of FIT were 0.0% (95% CI: 0.0-30.9) in subjects with only proximal versus 21.4% (95% CI: 8.3-41.0) in those with distal nonadvanced adenomas; 5.3% (95% CI: 0.0-26.0) in women versus 26.3% (95% CI: 9.2-51.2) in men; 9.5% (95% CI: 1.2-30.4) in younger versus 23.5% (95% CI: 6.8-49.9) in older subjects. Sigmoidoscopy had a significantly higher sensitivity for advanced adenomas than FIT. A single FIT showed very low sensitivity, especially in subjects with only proximal nonadvanced adenomas, in women, and in younger subjects. This points to the existence of "low" FIT performance in subgroups and the need for more tailored screening strategies.

Usefulness of the volume-viscosity swallow test for screening dysphagia in subacute stroke patients in rehabilitation income.

PubMed

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.

Performance of alternative strategies for primary cervical cancer screening in sub-Saharan Africa: systematic review and meta-analysis of diagnostic test accuracy studies

PubMed Central

Combescure, Christophe; Fokom-Defo, Victoire; Tebeu, Pierre Marie; Vassilakos, Pierre; Kengne, André Pascal; Petignat, Patrick

2015-01-01

Objective To assess and compare the accuracy of visual inspection with acetic acid (VIA), visual inspection with Lugol’s iodine (VILI), and human papillomavirus (HPV) testing as alternative standalone methods for primary cervical cancer screening in sub-Saharan Africa. Design Systematic review and meta-analysis of diagnostic test accuracy studies. Data sources Systematic searches of multiple databases including Medline, Embase, and Scopus for studies published between January 1994 and June 2014. Review methods Inclusion criteria for studies were: alternative methods to cytology used as a standalone test for primary screening; study population not at particular risk of cervical cancer (excluding studies focusing on HIV positive women or women with gynaecological symptoms); women screened by nurses; reference test (colposcopy and directed biopsies) performed at least in women with positive screening results. Two reviewers independently screened studies for eligibility and extracted data for inclusion, and evaluated study quality using the quality assessment of diagnostic accuracy studies 2 (QUADAS-2) checklist. Primary outcomes were absolute accuracy measures (sensitivity and specificity) of screening tests to detect cervical intraepithelial neoplasia grade 2 or worse (CIN2+). Results 15 studies of moderate quality were included (n=61 381 for VIA, n=46 435 for VILI, n=11 322 for HPV testing). Prevalence of CIN2+ did not vary by screening test and ranged from 2.3% (95% confidence interval 1.5% to 3.3%) in VILI studies to 4.9% (2.7% to 7.8%) in HPV testing studies. Positivity rates of VILI, VIA, and HPV testing were 16.5% (9.8% to 24.7%), 16.8% (11.0% to 23.6%), and 25.8% (17.4% to 35.3%), respectively. Pooled sensitivity was higher for VILI (95.1%; 90.1% to 97.7%) than VIA (82.4%; 76.3% to 87.3%) in studies where the reference test was performed in all women (P<0.001). Pooled specificity of VILI and VIA were similar (87.2% (78.1% to 92.8%) v 87.4% (77.1% to 93.4%); P=0.85). Pooled sensitivity and specificity were similar for HPV testing versus VIA (both P≥0.23) and versus VILI (both P≥0.16). Accuracy of VIA and VILI increased with sample size and time period. Conclusions For primary screening of cervical cancer in sub-Saharan Africa, VILI is a simple and affordable alternative to cytology that demonstrates higher sensitivity than VIA. Implementation studies are needed to assess the effect of these screening strategies on the incidence and outcomes of cervical cancer in the region. PMID:26142020

Primary screening for cervical cancer based on high-risk human papillomavirus (HPV) detection and HPV 16 and HPV 18 genotyping, in comparison to cytology.

PubMed

Agorastos, Theodoros; Chatzistamatiou, Kimon; Katsamagkas, Taxiarchis; Koliopoulos, George; Daponte, Alexandros; Constantinidis, Theocharis; Constantinidis, Theodoros C

2015-01-01

The objective of the present study is to assess the performance of a high-risk human papillomavirus (HR-HPV) DNA test with individual HPV-16/HPV-18 genotyping as a method for primary cervical cancer screening compared with liquid-based cytology (LBC) in a population of Greek women taking part in routine cervical cancer screening. The study, conducted by the "HEllenic Real life Multicentric cErvical Screening" (HERMES) study group, involved the recruitment of 4,009 women, aged 25-55, who took part in routine cervical screening at nine Gynecology Departments in Greece. At first visit cervical specimens were collected for LBC and HPV testing using the Roche Cobas 4800 system. Women found positive for either cytology or HPV were referred for colposcopy, whereas women negative for both tests will be retested after three years. The study is ongoing and the results of the first screening round are reported herein. Valid results for cytology and HPV testing were obtained for 3,993 women. The overall prevalence of HR-HPV was 12.7%, of HPV-16 2.7% and of HPV-18 1.4%. Of those referred for colposcopy, cervical intraepithelial neoplasia grade 2 or worse (CIN2+) was detected in 41 women (1.07%). At the threshold of CIN2+, cytology [atypical squamous cells of undetermined significance (ASC-US) or worse] and HPV testing showed a sensitivity of 53.7% and 100% respectively, without change between age groups. Cytology and HPV testing showed specificity of 96.8% and 90.3% respectively, which was increased in older women (≥30) in comparison to younger ones (25-29). Genotyping for HPV16/18 had similar accuracy to cytology for the detection of CIN2+ (sensitivity: 58.5%; specificity 97.5%) as well as for triage to colposcopy (sensitivity: 58.5% vs 53.7% for cytology). HPV testing has much better sensitivity than cytology to identify high-grade cervical lesions with slightly lower specificity. HPV testing with individual HPV-16/HPV-18 genotyping could represent a more accurate methodology for primary cervical cancer screening in comparison to liquid-based cytology, especially in older women.

Evaluation of the stereo optical OPTEC(R)5000 for aeromedical color vision screening.

DOT National Transportation Integrated Search

2013-08-01

Screening tests are valued for their ability to detect the presence (test sensitivity) and the absence (test specificity) of a disease or a specific condition such as color vision deficiencies(CVDs). From an aviation safety standpoint, it is importan...

Development and testing of monoclonal antibody-based rapid immunodiagnostic test kits for direct detection of Vibrio cholerae O139 synonym Bengal.

PubMed

Hasan, J A; Huq, A; Nair, G B; Garg, S; Mukhopadhyay, A K; Loomis, L; Bernstein, D; Colwell, R R

1995-11-01

We report on the development and testing of two monoclonal antibody-based rapid immunodiagnostic test kits, BengalScreen, a coagglutination test, and Bengal DFA, a direct fluorescent-antibody test, for direct detection of Vibrio cholerae O139 synonym Bengal in clinical and environmental specimens. The BengalScreen test requires less than 5 min to complete and can be used in the field. Bengal DFA, being more sensitive than BengalScreen, requires only one reagent and less than 20 min for detection and enumeration of V. cholerae O139 synonym Bengal. In tests for specificity, all 40 strains of V. cholerae O139 reacted with both test kits, whereas 157 strains of heterologous species examined did not, yielding 100% specificity in this study. A field trial was conducted in with both BengalScreen and Bengal DFA, and the results were compared with those obtained by conventional culture methods. BengalScreen demonstrated a sensitivity of 95%, a specificity of 100%, a positive predictive value of 100%, and a negative predictive value of 94%. Results obtained by Bengal DFA, on the other hand, were 100% sensitive and 100% specific and yielded 100% positive and negative predictive values compared with culture methods. In a second evaluation, 93 stool specimens from Mexico that were negative for V. cholerae O139 by culture were also tested with both the BengalScreen and Bengal DFA kits. None of the 93 specimens were positive for V. cholerae O139 by both tests. A concentration method was optimized for screening of environmental water samples for V. cholerae O139 synonym Bengal with rapid test kits. BengalScreen results were unequivocally positive when water samples contained at least 2.0 x 10(3) CFU/ml, whereas Bengal DFA demonstrated an unequivocally positive reaction when the water sample contained at least 1.5 x 10(2) CFU/ml. When Bengal DFA was compared with conventional culture methods for enumeration of V. cholerae O139 synonym Bengal organisms, no difference was observed.

Sensitivity and Specificity of 2 Autism Screeners Among Referred Children Between 16 and 48 Months of Age.

PubMed

Salisbury, Louisa A; Nyce, Jonathan D; Hannum, Charles D; Sheldrick, R Christopher; Perrin, Ellen C

2018-04-01

Autism screening is recommended by the American Academy of Pediatrics and the Centers for Disease Control and Prevention at ages 18 and 24 months. Popular screening tests have been validated for the age range of 16 to 30 months. However, only a minority of children with autism spectrum disorder (ASD) are identified by age 3 years, and many are not identified until after they enter school. Thus, we aimed to measure the sensitivity and specificity of 2 available screening tests for ASDs in children older than 30 months. We assessed the sensitivity and specificity of 2 ASD screening tools administered to parents of children who were referred to a developmental clinic between the ages of 16 and 48 months: the Modified Checklist for Autism in Toddlers (M-CHAT) and the Parent's Observations of Social Interactions (POSI), which is a component of a comprehensive screening instrument called, the Survey of Well-being of Young Children. Both the M-CHAT and the POSI had acceptable sensitivity (≥75%) among children across the age range studied. Their specificity was limited by the fact that the study was conducted in a developmental referral clinic. Two readily available screening tools, the POSI and the M-CHAT, have acceptable sensitivity in evaluating risk for autism in children at least to age 48 months. Further research should investigate their sensitivity and specificity when used in primary care settings.

Developing a Screening Algorithm for Type II Diabetes Mellitus in the Resource-Limited Setting of Rural Tanzania.

PubMed

West, Caroline; Ploth, David; Fonner, Virginia; Mbwambo, Jessie; Fredrick, Francis; Sweat, Michael

2016-04-01

Noncommunicable diseases are on pace to outnumber infectious disease as the leading cause of death in sub-Saharan Africa, yet many questions remain unanswered with concern toward effective methods of screening for type II diabetes mellitus (DM) in this resource-limited setting. We aim to design a screening algorithm for type II DM that optimizes sensitivity and specificity of identifying individuals with undiagnosed DM, as well as affordability to health systems and individuals. Baseline demographic and clinical data, including hemoglobin A1c (HbA1c), were collected from 713 participants using probability sampling of the general population. We used these data, along with model parameters obtained from the literature, to mathematically model 8 purposed DM screening algorithms, while optimizing the sensitivity and specificity using Monte Carlo and Latin Hypercube simulation. An algorithm that combines risk assessment and measurement of fasting blood glucose was found to be superior for the most resource-limited settings (sensitivity 68%, sensitivity 99% and cost per patient having DM identified as $2.94). Incorporating HbA1c testing improves the sensitivity to 75.62%, but raises the cost per DM case identified to $6.04. The preferred algorithms are heavily biased to diagnose those with more severe cases of DM. Using basic risk assessment tools and fasting blood sugar testing in lieu of HbA1c testing in resource-limited settings could allow for significantly more feasible DM screening programs with reasonable sensitivity and specificity. Copyright © 2016 Southern Society for Clinical Investigation. Published by Elsevier Inc. All rights reserved.

Faecal immunochemical tests versus guaiac faecal occult blood tests: what clinicians and colorectal cancer screening programme organisers need to know.

PubMed

Tinmouth, Jill; Lansdorp-Vogelaar, Iris; Allison, James E

2015-08-01

Although colorectal cancer (CRC) is a common cause of cancer-related death, it is fortunately amenable to screening with faecal tests for occult blood and endoscopic tests. Despite the evidence for the efficacy of guaiac-based faecal occult blood tests (gFOBT), they have not been popular with primary care providers in many jurisdictions, in part because of poor sensitivity for advanced colorectal neoplasms (advanced adenomas and CRC). In order to address this issue, high sensitivity gFOBT have been recommended, however, these tests are limited by a reduction in specificity compared with the traditional gFOBT. Where colonoscopy is available, some providers have opted to recommend screening colonoscopy to their patients instead of faecal testing, as they believe it to be a better test. Newer methods for detecting occult human blood in faeces have been developed. These tests, called faecal immunochemical tests (FIT), are immunoassays specific for human haemoglobin. FIT hold considerable promise over the traditional guaiac methods including improved analytical and clinical sensitivity for CRC, better detection of advanced adenomas, and greater screenee participation. In addition, the quantitative FIT are more flexible than gFOBT as a numerical result is reported, allowing customisation of the positivity threshold. When compared with endoscopy, FIT are less sensitive for the detection of advanced colorectal neoplasms when only one time testing is applied to a screening population; however, this is offset by improved participation in a programme of annual or biennial screens and a better safety profile. This review will describe how gFOBT and FIT work and will present the evidence that supports the use of FIT over gFOBT, including the cost-effectiveness of FIT relative to gFOBT. Finally, specific issues related to FIT implementation will be discussed, particularly with respect to organised CRC screening programmes. 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.

Sensitivity and specificity of digital retinal imaging for screening diabetic retinopathy.

PubMed

Lopez-Bastida, J; Cabrera-Lopez, F; Serrano-Aguilar, P

2007-04-01

To assess the effectiveness of a non-mydriatic digital camera (45 degrees -30 degrees photographs) compared with the reference method for screening diabetic retinopathy. Type 1 and 2 diabetic patients (n = 773; 1546 eyes) underwent screening for diabetic retinopathy in a prospective observational study. Hospital-based non-mydriatic digital retinal imaging by a consultant specialist in retinal diseases was compared with slit-lamp biomicroscopy and indirect ophthalmoscopy through dilated pupils, as a gold standard, previously performed in a community health centre by another consultant specialist in retinal diseases. The main outcome measures were sensitivity and specificity of screening methods and prevalence of diabetic retinopathy. The prevalence of any form of diabetic retinopathy was 42.4% (n = 328); the prevalence of sight-threatening including macular oedema and proliferative retinopathy was 9.6% (n = 74). Sensitivity of detection of any diabetic retinopathy by digital imaging was 92% (95% confidence interval 90, 94). Specificity of detection of any diabetic retinopathy was 96% (95, 98). The predictive value of the negative tests was 94% and of a positive test 95%. For sight-threatening retinopathy digital imaging had a sensitivity of 100%. A high sensitivity and specificity are essential for an effective screening programme. These results confirm digital retinal imaging with a non-mydriatic camera as an effective option in community-based screening programmes for diabetic retinopathy.

Screening athletes with Down syndrome for ocular disease.

PubMed

Gutstein, Walter; Sinclair, Stephen H; North, Rachel V; Bekiroglu, N

2010-02-01

Persons with Down syndrome are well known to have a high prevalence of vision and eye health problems, many of which are undetected or untreated primarily because of infrequent ocular examinations. Public screening programs, directed toward the pediatric population, have become more popular and commonly use letter or symbol charts. This study compares 2 vision screening methods, the Lea Symbol chart and a newly developed interactive computer program, the Vimetrics Central Vision Analyzer (CVA), in their ability to identify ocular disease in the Down syndrome population. Athletes with Down syndrome participating in the European Special Olympics underwent an ocular screening including history, auto-refraction, colour vision assessment, stereopsis assessment, motility assessment, pupil reactivity, and tonometry testing, as well as anterior segment and fundus examinations to evaluate for ocular disease. Visual acuity was tested with the Lea chart and CVA to evaluate these as screening tests for detecting ocular disease as well as significant, uncorrected refractive errors. Among the 91 athletes that presented to the screening, 79 (158 eyes) were sufficiently cooperative for the examination to be completed. Mean age was 26 years +/-10.8 SD. Significant, uncorrected refractive errors (>/=1.00 spherical equivalent) were detected in 28 (18%) eyes and ocular pathology in 51 (32%) eyes. The Lea chart sensitivity and specificity were 43% and 74%, respectively, for detecting ocular pathology and 58% and 100% for detecting uncorrected refractive errors. The CVA sensitivity and specificity were 70% and 86% for detecting pathology and 71% and 100% for detecting uncorrected refractive errors. This study confirmed the findings of prior studies in identifying a significant presence of uncorrected refractive errors and ocular pathology in the Down syndrome population. Screening with the Lea symbol chart found borderline sufficient sensitivity and specificity for the test to be used for screening in this population. The better sensitivity and specificity of the CVA, if adjusted normative values are utilized, appear to make this test sufficient for testing Down syndrome children for identifying both refractive errors and ocular pathology. Copyright 2010 American Optometric Association. Published by Elsevier Inc. All rights reserved.

[Test and programme sensitivities of screening for colorectal cancer in Reggio Emilia].

PubMed

Campari, Cinzia; Sassatelli, Romano; Paterlini, Luisa; Camellini, Lorenzo; Menozzi, Patrizia; Cattani, Antonella

2011-01-01

to estimate the sensitivity of the immunochemical test for faecal occult blood (FOBT) and the sensitivity of the colorectal tumour screening programme in the province of Reggio Emilia. retrospective cohort study, including a sample of 80,357 people of both genders, aged 50-69, who underwent FOBT, during the first round of the screening programme in the province of Reggio Emilia, from April 2005 to December 2007. incidence of interval cancer. The proportional incidence method was used to estimate the sensitivity of FOBT and of the screening programme. Data were stratified according to gender, age and year of interval. the overall sensitivity of FOBT was 73.2% (95%IC 63.8-80.7). The sensitivity of FOBT was lower in females (70.5% vs 75.1%), higher in the 50-59 age group (78.6% vs 70.2%) and higher in the colon than rectum (75.1% vs 68.9%). The test had a significantly higher sensitivity in the 1st year of interval than in the 2nd (84.4% vs 60.5%; RR=0.39, 95%IC 0.22-0.70), a difference which was confirmed, also when data were stratified according to gender. The overall sensitivity of the programme is 70.9% (95%IC 61.5-78.5). No statistically significant differences were shown, if data were stratified according to gender, age or site. Again the sensitivity in the 1st year was significantly higher than in the 2nd year of interval (83.2% vs 57.0%; RR=0.41, 95%IC 0.24-0.69). Overall our data confirmed the findings of similar Italian studies, despite subgroup analysis showed some differences in sensitivity in our study.

Effectiveness of VIA, Pap, and HPV DNA Testing in a Cervical Cancer Screening Program in a Peri-Urban Community in Andhra Pradesh, India

PubMed Central

Gravitt, Patti E.; Paul, Proma; Katki, Hormuzd A.; Vendantham, Haripriya; Ramakrishna, Gayatri; Sudula, Mrudula; Kalpana, Basany; Ronnett, Brigitte M.; Vijayaraghavan, K.; Shah, Keerti V.

2010-01-01

Background While many studies have compared the efficacy of Pap cytology, visual inspection with acetic acid (VIA) and human papillomavirus (HPV) DNA assays for the detection cervical intraepithelial neoplasia and cancer, few have evaluated the program effectiveness. Methods and Findings A population-based sample of 5603 women from Medchal Mandal in Andhra Pradesh, India were invited to participate in a study comparing Pap cytology, VIA, and HPV DNA screening for the detection of CIN3+. Participation in primary screening and all subsequent follow-up visits was rigorously tracked. A 20% random sample of all women screened, in addition to all women with a positive screening test result underwent colposcopy with directed biopsy for final diagnosis. Sensitivity, specificity, positive and negative predictive values were adjusted for verification bias. HPV testing had a higher sensitivity (100%) and specificity (90.6%) compared to Pap cytology (sensitivity  =  78.2%; specificity = 86.0%) and VIA (sensitivity = 31.6%; specificity = 87.5%). Since 58% of the sample refused involvement and another 28% refused colposcopy or biopsy, we estimated that potentially 87.6% of the total underlying cases of CIN3 and cancer may have been missed due to program failures. Conclusions We conclude that despite our use of available resources, infrastructure, and guidelines for cervical cancer screening implementation in resource limited areas, community participation and non-compliance remain the major obstacles to successful reduction in cervical cancer mortality in this Indian population. HPV DNA testing was both more sensitive and specific than Pap cytology and VIA. The use of a less invasive and more user-friendly primary screening strategy (such as self-collected swabs for HPV DNA testing) may be required to achieve the coverage necessary for effective reduction in cervical cancer mortality. PMID:21060889

A Novel Quantum Dots-Based Point of Care Test for Syphilis

NASA Astrophysics Data System (ADS)

Yang, Hao; Li, Ding; He, Rong; Guo, Qin; Wang, Kan; Zhang, Xueqing; Huang, Peng; Cui, Daxiang

2010-05-01

One-step lateral flow test is recommended as the first line screening of syphilis for primary healthcare settings in developing countries. However, it generally shows low sensitivity. We describe here the development of a novel fluorescent POC (Point Of Care) test method to be used for screening for syphilis. The method was designed to combine the rapidness of lateral flow test and sensitiveness of fluorescent method. 50 syphilis-positive specimens and 50 healthy specimens conformed by Treponema pallidum particle agglutination (TPPA) were tested with Quantum Dot-labeled and colloidal gold-labeled lateral flow test strips, respectively. The results showed that both sensitivity and specificity of the quantum dots-based method reached up to 100% (95% confidence interval [CI], 91-100%), while those of the colloidal gold-based method were 82% (95% CI, 68-91%) and 100% (95% CI, 91-100%), respectively. In addition, the naked-eye detection limit of quantum dot-based method could achieve 2 ng/ml of anti-TP47 polyclonal antibodies purified by affinity chromatography with TP47 antigen, which was tenfold higher than that of colloidal gold-based method. In conclusion, the quantum dots were found to be suitable for labels of lateral flow test strip. Its ease of use, sensitiveness and low cost make it well-suited for population-based on-the-site syphilis screening.

A new method to address verification bias in studies of clinical screening tests: cervical cancer screening assays as an example.

PubMed

Xue, Xiaonan; Kim, Mimi Y; Castle, Philip E; Strickler, Howard D

2014-03-01

Studies to evaluate clinical screening tests often face the problem that the "gold standard" diagnostic approach is costly and/or invasive. It is therefore common to verify only a subset of negative screening tests using the gold standard method. However, undersampling the screen negatives can lead to substantial overestimation of the sensitivity and underestimation of the specificity of the diagnostic test. Our objective was to develop a simple and accurate statistical method to address this "verification bias." We developed a weighted generalized estimating equation approach to estimate, in a single model, the accuracy (eg, sensitivity/specificity) of multiple assays and simultaneously compare results between assays while addressing verification bias. This approach can be implemented using standard statistical software. Simulations were conducted to assess the proposed method. An example is provided using a cervical cancer screening trial that compared the accuracy of human papillomavirus and Pap tests, with histologic data as the gold standard. The proposed approach performed well in estimating and comparing the accuracy of multiple assays in the presence of verification bias. The proposed approach is an easy to apply and accurate method for addressing verification bias in studies of multiple screening methods. Copyright © 2014 Elsevier Inc. All rights reserved.

Repeat Cytology and Human Papillomavirus Screening Strategies in Detecting Preinvasive Cervical Lesions

PubMed Central

Li, Kemin; Yin, Rutie

2015-01-01

Abstract The aim of the present study was to determine the value of human papillomavirus (HPV) testing in screening patients with preinvasive cervical lesions. Seven hundred thirty-four women diagnosed with atypical squamous cells of undetermined significance (ASCUS+) cervical cytology during routine screening had additional cytologic testing and HPV DNA testing within 6 months of their diagnosis, after which all women who tested positive were referred for colposcopy and biopsy. The test findings were then used to determine the screening value of HPV for diagnosing preinvasive cervical lesions. Cytology and HPV testing were compared by conventional cytology. The odds ratio (OR) of sensitivity using ASCUS+ or low-grade squamous intraepithelial neoplasia (LSIL+) as a cutoff for detecting cervical intraepithelial neoplasia (CIN) II+ was, respectively, 0.78 (0.72, 0.85) and 0.82 (0.70, 0.95) (P < 0.01). The cytology for triage and conventional cytology had different sensitivities using ASCUS+ or LSIL+ as the cutoff (P < 0.01). The cytology or HPV testing and conventional cytology had a difference in sensitivity using ASCUS+, LSIL+, or high-grade squamous intraepithelial neoplasia (HSIL+) as the cutoff (P < 0.01). Cytology and HPV testing were also compared with conventional cytology. The OR of specificity using ASCUS+ or LSIL+ as the cutoff for the detection of CIN II+ was 1.97 (1.68, 2.31) and 1.10 (1.02, 1.18), respectively (P < 0.01). The cytology for triage and conventional cytology had a difference in specificity when ASCUS+ or LSIL+ was used as the cutoff (P < 0.01). Finally, the cytology or HPV testing and conventional cytology had a difference in specificity when ASCUS+, LSIL+, or HSIL+ was used as the cutoff (P < 0.01). Cytology and HPV testing and cytology for triage improved the specificity of detecting CIN II+, but this did not improve the sensitivity. Additionally, cytology or HPV testing improved the sensitivity of detecting CIN II+ but not the specificity. PMID:25654377

Diagnostic performance of dual-staining cytology for cervical cancer screening: A systematic literature review.

PubMed

Tjalma, Wiebren A A

2017-03-01

Cervical cancer screening saves lives. Secondary prevention in cervical cancer screening relies on the results of primary cytology and/or HPV testing. However, primary screening with cytology has a low sensitivity, and HPV screening has a low specificity. This means that either cancers are missed, or women are over-treated. To improve performance outcomes, the concept of dual-stain cytology (CINtec ® PLUS Cytology test) has been introduced. In this approach, additional staining with p16/Ki-67 is performed in cases where cytology results are abnormal (LSIL or ASCUS) and/or HPV-positive. Another way to describe this approach might be "diagnostic" cytology. In order to assess the value of this "diagnostic cytology", a systematic literature review was conducted of dual-stain cytology performance across multiple studies until May 2016. In a Belgian screening population (women age 25-65 years), dual-stain cytology was significantly more sensitive (66%) and slightly less specific (-1.0%) than cytology. In the population referred to colposcopy or with abnormal cytology (ASCUS, LSIL), dual-staining showed a significantly higher increase in specificity, and a slightly lower sensitivity than HPV testing. Specificity gains resulted in fewer false positives and an increase in the number of correct referrals to colposcopy. Dual-staining with p16/Ki-67 cytology is an attractive biomarker approach for triage in cervical cancer screening. Copyright © 2017 Elsevier B.V. All rights reserved.

Effect of education and gender adjustment on the sensitivity and specificity of a cognitive screening battery for dementia: results from the MoVIES Project. Monongahela Valley Independent Elders Survey.

PubMed

Belle, S H; Seaberg, E C; Ganguli, M; Ratcliff, G; DeKosky, S; Kuller, L H

1996-01-01

The Monongahela Valley Independent Elders Survey (MoVIES) used a multiphase process to identify demented persons among 1,366 randomly selected noninstitutionalized individuals 65 years and older. Raw test scores from a cognitive screening battery were used to identify cognitively impaired individuals who were referred for a clinical evaluation. Subsequently, test scores were adjusted for education and gender within age strata. Adjusting test scores affected sensitivity for dementia only among the most educated, increasing sensitivity among younger subjects and decreasing among the older subjects. Specificity increased among the least educated and the oldest subjects. Overall, the adjusted criteria did not perform as well as the unadjusted criteria in this sample. Adjustment for education will not necessarily improve the ability of a screening battery for cognitive function to identify demented persons, particularly if unadjusted scores perform well.

Results at recruitment from a randomized controlled trial comparing human papillomavirus testing alone with conventional cytology as the primary cervical cancer screening test.

PubMed

Ronco, Guglielmo; Giorgi-Rossi, Paolo; Carozzi, Francesca; Confortini, Massimo; Dalla Palma, Paolo; Del Mistro, Annarosa; Gillio-Tos, Anna; Minucci, Daria; Naldoni, Carlo; Rizzolo, Raffaella; Schincaglia, Patrizia; Volante, Renza; Zappa, Marco; Zorzi, Manuel; Cuzick, Jack; Segnan, Nereo

2008-04-02

In the first recruitment phase of a randomized trial of cervical cancer screening methods (New Technologies for Cervical Cancer Screening [NTCC] study), we compared screening with conventional cytology with screening by human papillomavirus (HPV) testing in combination with liquid-based cytology. HPV-positive women were directly referred to colposcopy if aged 35 or older; if younger, they were retested after 1 year. In the second recruitment phase of NTCC, we randomly assigned women to conventional cytology (n = 24,661) with referral to colposcopy if cytology indicated atypical squamous cells of undetermined significance or more severe abnormality or to testing for high-risk HPV DNA alone by Hybrid Capture 2 (n = 24,535) with referral to colposcopy if the test was positive at a concentration of HPV DNA 1 pg/mL or greater. For the main endpoint of the study, histologic detection of cervical intraepithelial neoplasia of grade 2 or more (CIN2+), we calculated and compared sensitivity and positive predictive value (PPV) of the two screening methods using HPV DNA cutoffs of 1 pg/mL and 2 pg/mL. All statistical tests were two-sided. For women aged 35-60 years, the relative sensitivity of HPV testing for detection of CIN2+ at a cutoff of 1 pg/mL vs conventional cytology was 1.92 (95% CI = 1.28 to 2.87) and the relative PPV was 0.80 (95% CI = 0.55 to 1.18). At a cutoff of 2 pg/mL HPV DNA, the relative sensitivity was 1.81 (95% CI = 1.20 to 2.72) and the relative PPV was 0.99 (95% CI = 0.67 to 1.46). In this age group, there was no evidence of heterogeneity between study phases. Among women aged 25-34 years, the relative sensitivity for detection of CIN2+ of HPV testing at a cutoff of 1 pg/mL vs cytology was 3.50 (95% CI = 2.11 to 5.82), statistically significantly larger (P = .019) than that observed in phase 1 at this age (1.58; 95% CI = 1.03 to 2.44). For women aged 35-60 years, HPV testing with a cutoff of 2 pg/mL achieves a substantial gain in sensitivity over cytology with only a small reduction in PPV. Among women aged 25-34 years, the large relative sensitivity of HPV testing compared with conventional cytology and the difference between relative sensitivity during phases 1 and 2 suggests that there is frequent regression of CIN2+ that are detected by direct referral of younger HPV-positive women to colposcopy. Thus, triage test or repeat testing is needed if HPV is to be used for primary testing in this context.

Determinants of Cervical Cancer Screening Accuracy for Visual Inspection with Acetic Acid (VIA) and Lugol’s Iodine (VILI) Performed by Nurse and Physician

PubMed Central

Raifu, Amidu O.; El-Zein, Mariam; Sangwa-Lugoma, Ghislain; Ramanakumar, Agnihotram; Walter, Stephen D.

2017-01-01

Background Visual inspection with acetic acid (VIA) and Lugol’s iodine (VILI) are used to screen women for cervical cancer in low-resource settings. Little is known about correlates of their diagnostic accuracy by healthcare provider. We examined determinants of VIA and VILI screening accuracy by examiner in a cross-sectional screening study of 1528 women aged 30 years or older in a suburb of Kinshasa, Democratic Republic of Congo. Methods We used a logistic regression model for sensitivity and specificity to estimate the diagnostic accuracy of VIA and VILI, independently performed by nurse and physician, as a function of sociodemographic and reproductive health characteristics. Results Nurses rated tests as positive more often than physicians (36.3% vs 30.2% for VIA, 26.2% vs 25.2% for VILI). Women’s age was the most important determinant of performance. It was inversely associated with sensitivity (nurse’s VIA: p<0.001, nurse’s VILI: p = 0.018, physician’s VIA: p = 0.005, physician’s VILI: p = 0.006) but positively associated with specificity (all four combinations: p<0.001). Increasing parity adversely affected sensitivity and specificity, but the effects on sensitivity were significant for nurses only. The screening performance of physician’s assessment was significantly better than the nurse’s (difference in sensitivity: VIA = 13%, VILI = 16%; difference in specificity: VIA = 6%, VILI = 1%). Conclusions Age and parity influence the performance of visual tests for cervical cancer screening. Proper training of local healthcare providers in the conduct of these tests should take into account these factors for improved performance of VIA and VILI in detecting cervical precancerous lesions among women in limited-resource settings. PMID:28107486

Validation of English and Spanish-language versions of a screening questionnaire for rheumatoid arthritis in an underserved community.

PubMed

Potter, Jeffrey; Odutola, Jennifer; Gonzales, Christian Amurrio; Ward, Michael M

2008-08-01

Questionnaires to screen for rheumatoid arthritis (RA) have been tested in groups that were primarily well educated and Caucasian. We sought to validate the RA questions of the Connective Tissue Disease Screening Questionnaire (CSQ) in ethnic minorities in an underserved community, and to test a Spanish-language version. The Spanish-language version was developed by 2 native speakers. Consecutive English-speaking or Spanish-speaking patients in a community-based rheumatology practice completed the questionnaire. Diagnoses were confirmed by medical record review. Sensitivity and specificity of the questionnaire for a diagnosis of RA were computed for each language version, using 2 groups as controls: patients with noninflammatory conditions, and participants recruited from the community. The English-language version was tested in 53 patients with RA (79% ethnic minorities; mean education level 11.3 yrs), 85 rheumatology controls with noninflammatory conditions, and 82 community controls. Using 3 positive responses as indicating a positive screening test, the sensitivity of the questionnaire was 0.77, the specificity based on rheumatology controls was 0.45, and the specificity based on community controls was 0.94. The Spanish-language version was tested in 55 patients with RA (mean education level 7.8 yrs), 149 rheumatology controls, and 88 community controls. The sensitivity of the Spanish-language version was 0.87, with specificities of 0.60 and 0.97 using the rheumatology controls and community controls, respectively. The sensitivity of the English-language version of the RA questions of the CSQ was lower in this study than in other cohorts, reflecting differences in the performance of the questions in different ethnic or socioeconomic groups. The Spanish-language version demonstrated good sensitivity, and both had excellent specificity when tested in community controls.

Cytology versus HPV testing for cervical cancer screening in the general population.

PubMed

Koliopoulos, George; Nyaga, Victoria N; Santesso, Nancy; Bryant, Andrew; Martin-Hirsch, Pierre Pl; Mustafa, Reem A; Schünemann, Holger; Paraskevaidis, Evangelos; Arbyn, Marc

2017-08-10

Cervical cancer screening has traditionally been based on cervical cytology. Given the aetiological relationship between human papillomavirus (HPV) infection and cervical carcinogenesis, HPV testing has been proposed as an alternative screening test. To determine the diagnostic accuracy of HPV testing for detecting histologically confirmed cervical intraepithelial neoplasias (CIN) of grade 2 or worse (CIN 2+), including adenocarcinoma in situ, in women participating in primary cervical cancer screening; and how it compares to the accuracy of cytological testing (liquid-based and conventional) at various thresholds. We performed a systematic literature search of articles in MEDLINE and Embase (1992 to November 2015) containing quantitative data and handsearched the reference lists of retrieved articles. We included comparative test accuracy studies if all women received both HPV testing and cervical cytology followed by verification of the disease status with the reference standard, if positive for at least one screening test. The studies had to include women participating in a cervical cancer screening programme who were not being followed up for previous cytological abnormalities. We completed a 2 x 2 table with the number of true positives (TP), false positives (FP), true negatives (TN), and false negatives for each screening test (HPV test and cytology) used in each study. We calculated the absolute and relative sensitivities and the specificities of the tests for the detection of CIN 2+ and CIN 3+ at various thresholds and computed sensitivity (TP/(TP + TN) and specificity (TN/ (TN + FP) for each test separately. Relative sensitivity and specificity of one test compared to another test were defined as sensitivity of test-1 over sensitivity of test-2 and specificity of test-1 over specificity of test-2, respectively. To assess bias in the studies, we used the Quality Assessment of Diagnostic test Accuracy Studies (QUADAS) tool. We used a bivariate random-effects model for computing pooled accuracy estimates. This model takes into account the within- and between-study variability and the intrinsic correlation between sensitivity and specificity. We included a total of 40 studies in the review, with more than 140,000 women aged between 20 and 70 years old. Many studies were at low risk of bias. There were a sufficient number of included studies with adequate methodology to perform the following test comparisons: hybrid capture 2 (HC2) (1 pg/mL threshold) versus conventional cytology (CC) (atypical squamous cells of undetermined significance (ASCUS)+ and low-grade squamous intraepithelial lesions (LSIL)+ thresholds) or liquid-based cytology (LBC) (ASCUS+ and LSIL+ thresholds), other high-risk HPV tests versus conventional cytology (ASCUS+ and LSIL+ thresholds) or LBC (ASCUS+ and LSIL+ thresholds). For CIN 2+, pooled sensitivity estimates for HC2, CC and LBC (ASCUS+) were 89.9%, 62.5% and 72.9%, respectively, and pooled specificity estimates were 89.9%, 96.6%, and 90.3%, respectively. The results did not differ by age of women (less than or greater than 30 years old), or in studies with verification bias. Accuracy of HC2 was, however, greater in European countries compared to other countries. The results for the sensitivity of the tests were heterogeneous ranging from 52% to 94% for LBC, and 61% to 100% for HC2. Overall, the quality of the evidence for the sensitivity of the tests was moderate, and high for the specificity.The relative sensitivity of HC2 versus CC for CIN 2+ was 1.52 (95% CI: 1.24 to 1.86) and the relative specificity 0.94 (95% CI: 0.92 to 0.96), and versus LBC for CIN 2+ was 1.18 (95% CI: 1.10 to 1.26) and the relative specificity 0.96 (95% CI: 0.95 to 0.97). The relative sensitivity of HC2 versus CC for CIN 3+ was 1.46 (95% CI: 1.12 to 1.91) and the relative specificity 0.95 (95% CI: 0.93 to 0.97). The relative sensitivity of HC2 versus LBC for CIN 3+ was 1.17 (95% CI: 1.07 to 1.28) and the relative specificity 0.96 (95% CI: 0.95 to 0.97). Whilst HPV tests are less likely to miss cases of CIN 2+ and CIN 3+, these tests do lead to more unnecessary referrals. However, a negative HPV test is more reassuring than a negative cytological test, as the cytological test has a greater chance of being falsely negative, which could lead to delays in receiving the appropriate treatment. Evidence from prospective longitudinal studies is needed to establish the relative clinical implications of these tests.

Development and application of a general plasmid reference material for GMO screening.

PubMed

Wu, Yuhua; Li, Jun; Wang, Yulei; Li, Xiaofei; Li, Yunjing; Zhu, Li; Li, Jun; Wu, Gang

The use of analytical controls is essential when performing GMO detection through screening tests. Additionally, the presence of taxon-specific sequences is analyzed mostly for quality control during GMO detection. In this study, 11 commonly used genetic elements involving three promoters (P-35S, P-FMV35S and P-NOS), four marker genes (Bar, NPTII, HPT and Pmi), and four terminators (T-NOS, T-35S, T-g7 and T-e9), together with the reference gene fragments from six major crops of maize, soybean, rapeseed, rice, cotton and wheat, were co-integrated into the same single plasmid to construct a general reference plasmid pBI121-Screening. The suitability test of pBI121-Screening plasmid as reference material indicated that the non-target sequence on the pBI121-Screening plasmid did not affect the PCR amplification efficiencies of screening methods and taxon-specific methods. The sensitivity of screening and taxon-specific assays ranged from 5 to 10 copies of pBI121-Screening plasmid, meeting the sensitivity requirement of GMO detection. The construction of pBI121-Screening solves the lack of a general positive control for screening tests, thereby reducing the workload and cost of preparing a plurality of the positive control. Copyright © 2016 Elsevier B.V. All rights reserved.

How to improve colon cancer screening rates

PubMed Central

Alberti, Luiz Ronaldo; Garcia, Diego Paim Carvalho; Coelho, Debora Lucciola; De Lima, David Correa Alves; Petroianu, Andy

2015-01-01

Colorectal carcinoma is a common cause of death throughout the world and may be prevented by routine control, which can detect precancerous neoplasms and early cancers before they undergo malignant transformation or metastasis. Three strategies may improve colon cancer screening rates: convince the population about the importance of undergoing a screening test; achieve higher efficacy in standard screening tests and make them more available to the community and develop new more sensitive and efficacious screening methods and make them available as routine tests. In this light, the present study seeks to review these three means through which to increase colon cancer screening rates. PMID:26688708

Impact of variations in triage cytology interpretation on human papillomavirus-based cervical screening and implications for screening algorithms.

PubMed

Ronco, Guglielmo; Zappa, Marco; Franceschi, Silvia; Tunesi, Sara; Caprioglio, Adele; Confortini, Massimo; Del Mistro, Annarosa; Carozzi, Francesca; Segnan, Nereo; Zorzi, Manuel; Giorgi-Rossi, Paolo

2016-11-01

Women positive to human papillomavirus (HPV+) testing at cervical screening need triage, typically cytology and immediate colposcopy in case of atypical squamous cells of undetermined significance (ASCUS) or worse (ASCUS+) or, in cytology-normal HPV+ women, HPV test repeat after 1 year and colposcopy referral if still HPV+. Our hypothesis was that substantial variations in triage positivity and sensitivity may produce little variation in overall referral to colposcopy and on sensitivity of the entire screening process. Centre- and age-aggregated data from 72,869 women aged 35-64 years were derived from 10 organised screening programmes which have piloted HPV screening in Italy since 2012. Overall colposcopy referral was evaluated as a function of immediate colposcopy referral and overall CIN2+ detection as a function of the proportion of all CIN2+ detected by immediate referral (a proxy of cytology's sensitivity). We fitted additive regression models, adjusted for centre, age, compliance to HPV retesting and to colposcopy, by generalised estimation equations. The proportion of HPV+ women directly referred to colposcopy varied across programmes (20-57%; average 37%) and so did CIN2+ detection (49-94%; average 77%). Overall, 63% (range 41-75%) of HPV+ were referred to colposcopy either immediately or at HPV repeat. An absolute 10% increase in immediate colposcopy referral resulted in 4.2% (95% CI: 3.3-5.1%) increase in overall referral. An absolute 10% increase in cytology's sensitivity resulted in a 1.1% (95% CI: 0.1-2.0%) increase in overall CIN2+ detection. Repeat HPV testing limits the effect of subjectivity of cytology interpretation on overall referral and sensitivity. These will change only slightly when replacing cytology with another test if the interval to HPV repeat remains unchanged. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

Recommendations for Methicillin-Resistant Staphylococcus aureus Prevention in Adult ICUs: A Cost-Effectiveness Analysis.

PubMed

Whittington, Melanie D; Atherly, Adam J; Curtis, Donna J; Lindrooth, Richard C; Bradley, Cathy J; Campbell, Jonathan D

2017-08-01

Patients in the ICU are at the greatest risk of contracting healthcare-associated infections like methicillin-resistant Staphylococcus aureus. This study calculates the cost-effectiveness of methicillin-resistant S aureus prevention strategies and recommends specific strategies based on screening test implementation. A cost-effectiveness analysis using a Markov model from the hospital perspective was conducted to determine if the implementation costs of methicillin-resistant S aureus prevention strategies are justified by associated reductions in methicillin-resistant S aureus infections and improvements in quality-adjusted life years. Univariate and probabilistic sensitivity analyses determined the influence of input variation on the cost-effectiveness. ICU. Hypothetical cohort of adults admitted to the ICU. Three prevention strategies were evaluated, including universal decolonization, targeted decolonization, and screening and isolation. Because prevention strategies have a screening component, the screening test in the model was varied to reflect commonly used screening test categories, including conventional culture, chromogenic agar, and polymerase chain reaction. Universal and targeted decolonization are less costly and more effective than screening and isolation. This is consistent for all screening tests. When compared with targeted decolonization, universal decolonization is cost-saving to cost-effective, with maximum cost savings occurring when a hospital uses more expensive screening tests like polymerase chain reaction. Results were robust to sensitivity analyses. As compared with screening and isolation, the current standard practice in ICUs, targeted decolonization, and universal decolonization are less costly and more effective. This supports updating the standard practice to a decolonization approach.

Fecal occult blood testing beliefs and practices of U.S. primary care physicians: serious deviations from evidence-based recommendations.

PubMed

Nadel, Marion R; Berkowitz, Zahava; Klabunde, Carrie N; Smith, Robert A; Coughlin, Steven S; White, Mary C

2010-08-01

Fecal occult blood testing (FOBT) is an important option for colorectal cancer screening that should be available in order to achieve high population screening coverage. However, results from a national survey of clinical practice in 1999-2000 indicated that many primary care physicians used inadequate methods to implement FOBT screening and follow-up. To determine whether methods to screen for fecal occult blood have improved, including the use of newer more sensitive stool tests. Cross-sectional national survey of primary care physicians. Participants consisted of 1,134 primary care physicians who reported ordering or performing FOBT in the 2006-2007 National Survey of Primary Care Physicians' Recommendations and Practices for Cancer Screening. Self-reported data on details of FOBT implementation and follow-up of positive results. Most physicians report using standard guaiac tests; higher sensitivity guaiac tests and immunochemical tests were reported by only 22.0% and 8.9%, respectively. In-office testing, that is, testing of a single specimen collected during a digital rectal examination in the office, is still widely used although inappropriate for screening: 24.9% of physicians report using only in-office tests and another 52.9% report using both in-office and home tests. Recommendations improved for follow-up after a positive test: fewer physicians recommend repeating the FOBT (17.8%) or using tests other than colonoscopy for the diagnostic work-up (6.6%). Only 44.3% of physicians who use home tests have reminder systems to ensure test completion and return. Many physicians continue to use inappropriate methods to screen for fecal occult blood. Intensified efforts to inform physicians of recommended technique and promote the use of tracking systems are needed.

The Childhood Asperger Syndrome Test (CAST): Test-Retest Reliability in a High Scoring Sample

ERIC Educational Resources Information Center

Allison, Carrie; Williams, Jo; Scott, Fiona; Stott, Carol; Bolton, Patrick; Baron-Cohen, Simon; Brayne, Carol

2007-01-01

The Childhood Asperger Syndrome Test (CAST) is a 37-item parental self-completion questionnaire designed to screen for high-functioning autism spectrum conditions in epidemiological research. The CAST has previously demonstrated good accuracy for use as a screening test, with high sensitivity in studies with primary school aged children in…

Rapid automated method for screening of enteric pathogens from stool specimens.

PubMed Central

Villasante, P A; Agulla, A; Merino, F J; Pérez, T; Ladrón de Guevara, C; Velasco, A C

1987-01-01

A total of 800 colonies suggestive of Salmonella, Shigella, or Yersinia species isolated on stool differential agar media were inoculated onto both conventional biochemical test media (triple sugar iron agar, urea agar, and phenylalanine agar) and Entero Pathogen Screen cards of the AutoMicrobic system (Vitek Systems, Inc., Hazelwood, Mo.). Based on the conventional tests, the AutoMicrobic system method yielded the following results: 587 true-negatives, 185 true-positives, 2 false-negatives, and 26 false-positives (sensitivity, 99%; specificity, 96%). Both true-positive and true-negative results were achieved considerably earlier than false results (P less than 0.001). The Entero Pathogen Screen card method is a fast, easy, and sensitive method for screening for Salmonella, Shigella, or Yersinia species. The impossibility of screening for oxidase-positive pathogens is a minor disadvantage of this method. PMID:3553230

[Fool's gold standards in language screening. Sensitivity and specificity of the Hessian child language screening test (Kindersprachscreening, KiSS)].

PubMed

Neumann, K; Holler-Zittlau, I; van Minnen, S; Sick, U; Zaretsky, Y; Euler, H A

2011-01-01

The German Kindersprachscreening (KiSS) is a universal speech and language screening test for large-scale identification of Hessian kindergarten children requiring special educational language training or clinical speech/language therapy. To calculate the procedural screening validity, 257 children (aged 4.0 to 4.5 years) were tested using KiSS and four language tests (Reynell Development Language Scales III, Patholinguistische Diagnostik, PLAKSS, AWST-R). The majority or consensus judgements of three speech-language professionals, based on the language test results, served as a reference criterion. The base (fail) rates of the professionals were either self-determined or preset based on known prevalence rates. Screening validity was higher for preset than for self-determined base rates due to higher inter-judge agreement. The confusion matrices of the overall index classification of the KiSS (speech-language abnormalities with educational or clinical needs) with the fixed base rate expert judgement about language impairment, including fluency or voice disorders, yielded a sensitivity of 88% and a specificity of 78%, for just language impairment 84% and 75%, respectively. Specificities for disorders requiring clinical diagnostics in the KiSS (language impairment alone or combined with fluency/voice disorders) related to the test-based consensus expert judgment was about 93%. Sensitivities were unsatisfactory because the differentiation between educational and clinical needs requires improvement. Since the judgement concordances between the speech-language professionals was only moderate, the development of a comprehensive German reference test for speech and language disorders with evidence-based algorithmic decision rules rather than subjective clinical judgement is advocated.

The Clinical Aspects of Newborn Screening: Importance of Newborn Screening Follow-Up

ERIC Educational Resources Information Center

James, Philip M.; Levy, Harvey L.

2006-01-01

The aim of newborn screening is to identify presymptomatic healthy infants that will develop significant metabolic or endocrine derangements if left undiagnosed and untreated. The goal of ultimately reducing or eliminating irreversible sequelae is reached by maximizing test sensitivity of the primary newborn screening that measures specific…

The PHQ-PD as a Screening Tool for Panic Disorder in the Primary Care Setting in Spain

PubMed Central

Wood, Cristina Mae; Ruíz-Rodríguez, Paloma; Tomás-Tomás, Patricia; Gracia-Gracia, Irene; Dongil-Collado, Esperanza; Iruarrizaga, M. Iciar

2016-01-01

Introduction Panic disorder is a common anxiety disorder and is highly prevalent in Spanish primary care centres. The use of validated tools can improve the detection of panic disorder in primary care populations, thus enabling referral for specialized treatment. The aim of this study is to determine the accuracy of the Patient Health Questionnaire-Panic Disorder (PHQ-PD) as a screening and diagnostic tool for panic disorder in Spanish primary care centres. Method We compared the psychometric properties of the PHQ-PD to the reference standard, the Structured Clinical Interview for DSM-IV Axis I Disorders (SCID-I) interview. General practitioners referred 178 patients who completed the entire PHQ test, including the PHQ-PD, to undergo the SCID-I. The sensitivity, specificity, positive and negative predictive values and positive and negative likelihood ratios of the PHQ-PD were assessed. Results The operating characteristics of the PHQ-PD are moderate. The best cut-off score was 5 (sensitivity .77, specificity .72). Modifications to the questionnaire's algorithms improved test characteristics (sensitivity .77, specificity .72) compared to the original algorithm. The screening question alone yielded the highest sensitivity score (.83). Conclusion Although the modified algorithm of the PHQ-PD only yielded moderate results as a diagnostic test for panic disorder, it was better than the original. Using only the first question of the PHQ-PD showed the best psychometric properties (sensitivity). Based on these findings, we suggest the use of the screening questions for screening purposes and the modified algorithm for diagnostic purposes. PMID:27525977

Digital Rectal Examination and Balloon Expulsion Test in the Study of Defecatory Disorders: Are They Suitable as Screening or Excluding Tests?

PubMed

Caetano, Ana C; Santa-Cruz, André; Rolanda, Carla

2016-01-01

Background . Rome III criteria add physiological criteria to symptom-based criteria of chronic constipation (CC) for the diagnosis of defecatory disorders (DD). However, a gold-standard test is still lacking and physiological examination is expensive and time-consuming. Aim . Evaluate the usefulness of two low-cost tests-digital rectal examination (DRE) and balloon expulsion test (BET)-as screening or excluding tests of DD. Methods . We performed a systematic search in PUBMED and MEDLINE. We selected studies where constipated patients were evaluated by DRE or BET. Heterogeneity was assessed and random effect models were used to calculate the sensitivity, specificity, and negative predictive value (NPV) of the DRE and the BET. Results . Thirteen studies evaluating BET and four studies evaluating DRE (2329 patients) were selected. High heterogeneity ( I 2 > 80%) among studies was demonstrated. The studies evaluating the BET showed a sensitivity and specificity of 67% and 80%, respectively. Regarding the DRE, a sensitivity of 80% and specificity of 84% were calculated. NPV of 72% for the BET and NPV of 64% for the DRE were estimated. The sensitivity and specificity were similar when we restrict the analysis to studies using Rome criteria to define CC. The BET seems to perform better when a cut-off time of 2 minutes is used and when it is compared with a combination of physiological tests. Considering the DRE, strict criteria seem to improve the sensitivity but not the specificity of the test. Conclusion . Neither of the low-cost tests seems suitable for screening or excluding DD.

Point-of-care test for cervical cancer in LMICs.

PubMed

Mohammed, Sulma I; Ren, Wen; Flowers, Lisa; Rajwa, Bartek; Chibwesha, Carla J; Parham, Groesbeck P; Irudayaraj, Joseph M K

2016-04-05

Cervical cancer screening using Papanicolaou's smear test has been highly effective in reducing death from this disease. However, this test is unaffordable in low- and middle-income countries, and its complexity has limited wide-scale uptake. Alternative tests, such as visual inspection with acetic acid or Lugol's iodine and human papillomavirus DNA, are sub-optimal in terms of specificity and sensitivity, thus sensitive and affordable tests with high specificity for on-site reporting are needed. Using proteomics and bioinformatics, we have identified valosin-containing protein (VCP) as differentially expressed between normal specimens and those with cervical intra-epithelial neoplasia grade 2/3 (CIN2/CIN3+) or worse. VCP-specific immunohistochemical staining (validated by a point-of-care technology) provided sensitive (93%) and specific (88%) identification of CIN2/CIN3+ and may serve as a critical biomarker for cervical-cancer screening. Future efforts will focus on further refinements to enhance analytic sensitivity and specificity of our proposed test, as well as on prototype development.

Comparison of the clinical performances of the AdvanSure HPV Screening Real-Time PCR, the Abbott Real-Time High-Risk HPV Test, and the Hybrid Capture High-Risk HPV DNA Test for Cervical Cancer Screening.

PubMed

Chung, Hae-Sun; Hahm, Chorong; Lee, Miae

2014-09-01

The clinical performance of three human papillomavirus (HPV) DNA commercial assays for cervical cancer screening was evaluated; the AdvanSure HPV Screening Real-Time PCR (AdvanSure PCR; LG Life Sciences) that was developed recently for the detection of both high-risk and low-risk genotypes, the Abbott RealTime High-Risk HPV Test (Abbott PCR; Abbott Molecular) and the Hybrid Capture High-Risk HPV DNA test (HC2; Qiagen). The three different HPV DNA tests were compared using cytology samples obtained from 619 women who underwent routine cervical cancer screening. The gold-standard assay was histopathological confirmation of cervical intraepithelial neoplasia of grade 2 or worse. The clinical sensitivities of the AdvanSure PCR, the Abbott PCR and the HC2 for the detection of cervical intraepithelial neoplasia of grade 2 or worse were 95.5%, 95.5% and 100%, respectively, while the clinical specificities were 61.6%, 86.4% and 83.3%, respectively. There were no significant differences in the clinical sensitivities of the Abbott PCR and the AdvanSure PCR compared to the HC2. The clinical specificities of the Abbott PCR and the AdvanSure PCR for the detection of HPV types 16/18 were 97.8% and 98.5%, respectively. For cervical cancer screening, all three tests showed relatively good clinical sensitivities, but the AdvanSure PCR had lower clinical specificity than the Abbott PCR and the HC2. The AdvanSure PCR and the Abbott PCR assays have the advantage of being automated and the ability to distinguish between HPV types 16/18 and other HPV types. The two real-time PCR assays could be useful tools in HPV testing for cervical cancer screening. Copyright © 2014 Elsevier B.V. All rights reserved.

75 FR 28619 - Meeting of the Advisory Committee on Blood Safety and Availability

Federal Register 2010, 2011, 2012, 2013, 2014

2010-05-21

... began prior to the availability of tests for HIV in early 1985. The deferral has existed in its current form since September 1985. This and other related FDA policies are designed to address the major... screened using highly sensitive tests, screening tests can be falsely negative during the ``window period...

[Methicillin resistance detection in Staphylococcus aureus: comparison between conventional methods and MRSA-Screen latex agglutination technique].

PubMed

Soloaga, R; Corso, A; Gagetti, P; Faccone, D; Galas, M

2004-01-01

Methicillin-resistant Staphylococcus aureus (MRSA) is a significant pathogen that has emerged over the last four decades, causing both nosocomial and community-acquired infections. Rapid and accurate detection of methicillin resistance in S. aureus is important for the use of appropriate antimicrobial therapy and for the control of nosocomial spread of MRSA strains. We evaluated the efficiency of conventional methods for detection of methicillin resistance such as the disk diffusion, agar dilution, oxacillin agar screen test, and the latex agglutination test MRSA-Screen latex, in 100 isolates of S. aureus, 79 mecA positive and 21 mecA negative. The MRSA-Screen latex (Denka Seiken, Niigata, Japón), is a latex agglutination method that detects the presence of PLP-2a, product of mecA gene in S. aureus. The PCR of the mecA gene was used as the "gold standard" for the evaluation of the different methods tested. The percentages of sensitivity and specificity were as follows: disk difusión 97 and 100%, agar dilution 97 and 95%, oxacillin agar screen test 100 and 100%, and MRSA-Screen latex, 100 and 100 %. All methods presented high sensitivity and specificity, but MRSA-Screen latex had the advantage of giving a reliable result, equivalent to PCR, in only 15 minutes.

Phaeochromocytoma: diagnostic challenges for biochemical screening and diagnosis.

PubMed

Barron, Jeffrey

2010-08-01

The aim of this article is to provide knowledge of the origin of catecholamines and metabolites so that there can be an informed approach to the methods for biochemical screening for a possible phaeochromocytoma; The article includes a review of catecholamine and metadrenaline metabolism, with methods used in biochemical screening. In the adrenal medulla and a phaeochromocytoma, catecholamines continuously leak from chromaffin granules into the cytoplasm and are converted to metadrenalines. For a phaeochromocytoma to become biochemically detectable, metnoradrenaline secretion needs to rise fourfold, whereas noradrenaline secretion needs to rise 15-fold. The prevalence of a sporadic phaeochromocytoma is low; therefore false-positive results exceed true-positive results. Assay sensitivity is high because it is important not to miss a possible phaeochromocytoma. The use of urine or plasma fractionated metadrenalines as the first-line test has been recommended due to improved sensitivity. A negative result excludes a phaeochromocytoma. Only after a sporadic phaeochromocytoma has been diagnosed biochemically is it cost effective to request imaging. Sensitivities and specificities of the assays differ according to pre-test probabilities of the presence of a phaeochromocytoma, with hereditary and incidentalomas having a higher pre-test probability than sporadic phaeochromocytoma. In conclusion, in screening for a possible phaeochromocytoma, biochemical investigations should be completed first to exclude or establish the diagnosis. The preferred biochemical screening test is fractionated metadrenalines, including methoxytyramine so as not to miss dopamine-secreting tumours.

Transabdominal ultrasonography as a screening test for second-trimester placenta previa.

PubMed

Quant, Hayley S; Friedman, Alexander M; Wang, Eileen; Parry, Samuel; Schwartz, Nadav

2014-03-01

To determine the test characteristics of transabdominal ultrasonography as a screening test for second-trimester placenta previa. This secondary analysis of a prospective cohort study evaluated the distance from the placental edge to the internal os (placenta-cervix distance) through both transabdominal and transvaginal ultrasonography during the anatomic survey. Patients were recruited in the Maternal-Fetal Medicine Ultrasound Unit at the Hospital of the University of Pennsylvania, an urban tertiary care center. Transabdominal placenta-cervix distance cutoffs with high sensitivity for detection of previa and low-lying placenta were identified, and test characteristics were calculated. Follow-up ultrasound data, pregnancy, and delivery outcomes for those with second-trimester previa or low-lying placenta were obtained. One thousand two hundred fourteen women were included in the analysis. A transabdominal placenta-cervix distance cutoff of 4.2 cm was 93.3% sensitive and 76.7% specific for detection of previa with a 99.8% negative predictive value at a screen-positive rate of 25.0%. A cutoff of 2.8 cm was 86.7% sensitive and 90.5% specific with a 99.6% negative predictive value at a screen-positive rate of 11.4%. Only 9.8% (four of 41) of previas and low-lying placentas persisted through delivery. Transabdominal ultrasonography is an effective screening test for second-trimester placenta previa. At centers not performing universal transvaginal ultrasonography at the time of the anatomic survey, evidence-based transabdominal placenta-cervix distance cutoffs can optimize the identification of patients who require further surveillance for previa.

Rapid tests for sexually transmitted infections (STIs): the way forward

PubMed Central

Peeling, R W; Holmes, K K; Mabey, D

2006-01-01

In the developing world, laboratory services for sexually transmitted infections (STIs) are either not available, or where limited services are available, patients may not be able to pay for or physically access those services. Despite the existence of national policy for antenatal screening to prevent congenital syphilis and substantial evidence that antenatal screening is cost‐effective, implementation of syphilis screening programmes remains unacceptably low because of lack of screening tools that can be used in primary health care settings. The World Health Organization Sexually Transmitted Diseases Diagnostics Initiative (SDI) has developed the ASSURED criteria as a benchmark to decide if tests address disease control needs: Affordable, Sensitive, Specific, User‐friendly, Rapid and robust, Equipment‐free and Deliverable to end‐users. Rapid syphilis tests that can be used with whole blood approach the ASSURED criteria and can now be deployed in areas where no previous screening has been possible. Although rapid tests for chlamydia and gonorrhoea lack sensitivity, more tests are in development. The way forward for STI diagnostics requires a continuing quest for ASSURED tests, the development of a road map for test introduction, sustainable programmes for quality assurance, and the creation of a robust infrastructure linked to HIV prevention that ensures sustainability of STI control efforts that includes viral STIs. PMID:17151023

Rapid tests for sexually transmitted infections (STIs): the way forward.

PubMed

Peeling, R W; Holmes, K K; Mabey, D; Ronald, A

2006-12-01

In the developing world, laboratory services for sexually transmitted infections (STIs) are either not available, or where limited services are available, patients may not be able to pay for or physically access those services. Despite the existence of national policy for antenatal screening to prevent congenital syphilis and substantial evidence that antenatal screening is cost-effective, implementation of syphilis screening programmes remains unacceptably low because of lack of screening tools that can be used in primary health care settings. The World Health Organization Sexually Transmitted Diseases Diagnostics Initiative (SDI) has developed the ASSURED criteria as a benchmark to decide if tests address disease control needs: Affordable, Sensitive, Specific, User-friendly, Rapid and robust, Equipment-free and Deliverable to end-users. Rapid syphilis tests that can be used with whole blood approach the ASSURED criteria and can now be deployed in areas where no previous screening has been possible. Although rapid tests for chlamydia and gonorrhoea lack sensitivity, more tests are in development. The way forward for STI diagnostics requires a continuing quest for ASSURED tests, the development of a road map for test introduction, sustainable programmes for quality assurance, and the creation of a robust infrastructure linked to HIV prevention that ensures sustainability of STI control efforts that includes viral STIs.

Clinical Sensitivity of Cystic Fibrosis Mutation Panels in a Diverse Population.

PubMed

Hughes, Erin E; Stevens, Colleen F; Saavedra-Matiz, Carlos A; Tavakoli, Norma P; Krein, Lea M; Parker, April; Zhang, Zhen; Maloney, Breanne; Vogel, Beth; DeCelie-Germana, Joan; Kier, Catherine; Anbar, Ran D; Berdella, Maria N; Comber, Paul G; Dozor, Allen J; Goetz, Danielle M; Guida, Louis; Kattan, Meyer; Ting, Andrew; Voter, Karen Z; van Roey, Patrick; Caggana, Michele; Kay, Denise M

2016-02-01

Infants are screened for cystic fibrosis (CF) in New York State (NYS) using an IRT-DNA algorithm. The purpose of this study was to validate and assess clinical validity of the US FDA-cleared Illumina MiSeqDx CF 139-Variant Assay (139-VA) in the diverse NYS CF population. The study included 439 infants with CF identified via newborn screening (NBS) from 2002 to 2012. All had been screened using the Abbott Molecular CF Genotyping Assay or the Hologic InPlex CF Molecular Test. All with CF and zero or one mutation were tested using the 139-VA. DNA extracted from dried blood spots was reliably and accurately genotyped using the 139-VA. Sixty-three additional mutations were identified. Clinical sensitivity of three panels ranged from 76.2% (23 mutations recommended for screening by ACMG/ACOG) to 79.7% (current NYS 39-mutation InPlex panel), up to 86.0% for the 139-VA. For all, sensitivity was highest in Whites and lowest in the Black population. Although the sample size was small, there was a nearly 20% increase in sensitivity for the Black CF population using the 139-VA (68.2%) over the ACMG/ACOG and InPlex panels (both 50.0%). Overall, the 139-VA is more sensitive than other commercially available panels, and could be considered for NBS, clinical, or research laboratories conducting CF screening. © 2015 WILEY PERIODICALS, INC.

Human papillomavirus testing and liquid-based cytology in primary screening of women younger than 35 years: results at recruitment for a randomised controlled trial.

PubMed

Ronco, Guglielmo; Giorgi-Rossi, Paolo; Carozzi, Francesca; Dalla Palma, Paolo; Del Mistro, Annarosa; De Marco, Laura; De Lillo, Margherita; Naldoni, Carlo; Pierotti, Paola; Rizzolo, Raffaella; Segnan, Nereo; Schincaglia, Patrizia; Zorzi, Manuel; Confortini, Massimo; Cuzick, Jack

2006-07-01

Testing for human papillomavirus (HPV) DNA is more sensitive but less specific than cytological analysis. Loss in specificity is most relevant in women younger than 35 years because of increased HPV prevalence. We aimed to compare conventional screening with an experimental strategy in women aged 25-34 years, and investigate the effect of different criteria of referral to define the best methods of HPV screening. Women were randomly assigned to the conventional procedure (standard cytology, with referral to colposcopy if cytology showed atypical squamous cells of undetermined significance or more [ASCUS+]) or an experimental procedure (liquid-based cytology and testing for high-risk HPV types, with referral to colposcopy with ASCUS+ cytology). Women positive for HPV (cutoff > or = 1 pg/mL) but with normal cytology were retested after 1 year. The main endpoint was the presence of cervical intraepithelial neoplasia at grade 2 or more (CIN2+) in reviewed histology. The main analysis was by intention to screen. This trial is registered as an International Standard Randomised Controlled Trial, number ISRCTN81678807. We randomly assigned 5808 women aged 25-34 years to the conventional group and 6002 to the experimental group. The experimental procedure was significantly more sensitive than the conventional procedure (55 vs 33 CIN2+ lesions detected; relative sensitivity 1.61 [95% CI 1.05-2.48]), but had a lower positive predictive value (PPV; relative PPV 0.55 [0.37-0.82]). HPV testing (> or = 1 pg/mL) with cytology triage was also more sensitive than conventional cytology (relative sensitivity 1.58 [1.03-2.44], relative PPV 0.78 [0.52-1.16]). Relative PPV could be improved, with minimum loss in sensitivity, by use of a 2 pg/mL cutoff for HPV testing. Compared with conventional cytology, liquid-based cytology had a relative sensitivity of 1.32 (0.84-2.06), relative PPV 0.58 [0.38-0.89]). HPV testing alone with cytology triage could be a feasible alternative to conventional cytology for screening women younger than 35 years. Follow-up will provide data on possible overdiagnosis and on the feasibility of extended intervals.

Comparison of immunohistochemistry and polymerase chain reaction for detection of West Nile virus in naturally infected dead birds.

PubMed

Sandhu, Tejbir; Sidhu, Dalbinder; Dhillon, Major; Fang, Ying

2010-10-04

Credible vector-borne disease surveillance programs, especially in developing countries with limited resources, must include diagnostic tests that are efficient, inexpensive and simple and safe to administer while maintaining high levels of sensitivity and specificity. Since immunohistochemistry (IHC) includes most of these features, its sensitivity, specificity, predictive positive value (PPV) and predictive negative value (PNV) for West Nile virus (WNv) screening were compared to those of the gold standard, RT-PCR testing of kidney tissue in dead birds. IHC and RT-PCR were performed for WNv antigen on 41 dead birds (belonging to five orders) collected from the northwest region of the Riverside County of California. Fixed tissue sections were screened by IHC using polyclonal antibodies, and frozen kidney tissues were tested with RT-PCR. Kidney screening with IHC showed sensitivity, specificity, PPV and NPV of 95.45%, 73.68%, 80.77% and 93.33%, respectively. Based on WNv screening of kidney tissue, IHC and RT-PCR were in agreement with 95.45% (21/22) for positive dead birds and were in 100% (22/22) agreement when multi-organ screening by IHC was performed. The present study showed that IHC is as equally effective as RT-PCR in screening for WNv in dead birds. Therefore, IHC can effectively serve as a competent screening technique for those disease surveillance agencies that lack expensive RT-PCR technology while promoting safer biohazardous conditions, except at the initial stage of tissue collection.

Performance of rapid tests and algorithms for HIV screening in Abidjan, Ivory Coast.

PubMed

Loukou, Y G; Cabran, M A; Yessé, Zinzendorf Nanga; Adouko, B M O; Lathro, S J; Agbessi-Kouassi, K B T

2014-01-01

Seven rapid diagnosis tests (RDTs) of HIV were evaluated by a panel group who collected serum samples from patients in Abidjan (HIV-1 = 203, HIV-2 = 25, HIV-dual = 25, HIV = 305). Kit performances were recorded after the reference techniques (enzyme-linked immunosorbent assay). The following RDTs showed a sensitivity of 100% and a specificity higher than 99%: Determine, Oraquick, SD Bioline, BCP, and Stat-Pak. These kits were used to establish infection screening strategies. The combination with 2 or 3 of these tests in series or parallel algorithms showed that series combinations with 2 tests (Oraquick and Bioline) and 3 tests (Determine, BCP, and Stat-Pak) gave the best performances (sensitivity, specificity, positive predictive value, and negative predictive value of 100%). However, the combination with 2 tests appeared to be more onerous than the combination with 3 tests. The combination with Determine, BCP, and Stat-Pak tests serving as a tiebreaker could be an alternative to the HIV/AIDS serological screening in Abidjan.

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

PubMed

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

2015-08-01

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

Fasting glycaemia to simplify screening for gestational diabetes.

PubMed

Ryser Rüetschi, J; Jornayvaz, F R; Rivest, R; Huhn, E A; Irion, O; Boulvain, M

2016-12-01

Recommendations in Switzerland on screening for gestational diabetes endorse the International Association of Diabetes in Pregnancy Study Group consensus. As universal testing is time consuming and glucose loading is unpleasant, the recommendations include a simplification, not performing the glucose loading in women with fasting glycaemia <4.4 mmol/l. Our objective was to evaluate the diagnostic performance of this simplified strategy, compared with the complete test, in our population with a low prevalence of gestational diabetes. We collected 2298 complete 75-g glucose tolerance tests. We simulated stopping the test, so avoiding the glucose loading and further glycaemia, if fasting glycaemia was <4.4 or ≥5.1 mmol/l. Unselected pregnant women from Geneva and Basel, at 24-28 weeks of gestation. We calculated the sensitivity, and the percentage of women who would avoid the complete test with the strategy based on fasting glycaemia. The prevalence of gestational diabetes was 10.9% in our population. Among 251 women with gestational diabetes, fasting glycaemia was ≥5.1 mmol/l in 119 women (47.4%), between 4.4 and <5.1 mmol/l in 78 women (31.1%) and <4.4 mmol/l in 54 women (21.5%). Proceeding with the complete test only in women with fasting glycaemia between 4.4 and <5.1 mmol/l will result in a sensitivity of 78.5%. This strategy would avoid glucose loading in 63.8% of women. Screening with fasting glycaemia is an attractive alternative to universal screening with the complete 75-g glucose tolerance test. This strategy is, however, slightly less sensitive than previously reported in higher-risk populations. Fasting glycaemia can be considered as an alternative to the complete test for gestational diabetes screening. © 2016 Royal College of Obstetricians and Gynaecologists.

[Interval cancers and episode sensitivity in population-based screening programmes for colorectal cancer: a systematic review].

PubMed

Domènech, Xènia; Garcia, Montse; Benito, Llúcia; Binefa, Gemma; Vidal, Carmen; Milà, Núria; Moreno, Víctor

2015-01-01

To describe interval cancers (IC) and the sensitivity of colorectal cancer (CRC) screening programmes. A systematic review of the literature was conducted through a MEDLINE (PubMed) search. The search strategy combined the terms 'interval cancer', 'false negative', 'mass screening', 'screening' 'early detection of cancer', 'colorectal cancer' and 'bowel cancer'. Inclusion criteria consisted of population-based screening programmes, original articles written in English or Spanish and publication dates between 1999/01/01 and 2015/02/28. A narrative synthesis of the included articles was performed detailing the characteristics of the screening programmes, the IC rate, and the information sources used in each study. Thirteen articles were included. The episode sensitivity of CRC screening programmes ranged from 42.2% to 65.3% in programmes using the guaiac test and between 59.1% and 87.0% with the immunochemical test. We found a higher proportion of women who were diagnosed with IC and these lesions were mainly located in the proximal colon. There is wide variability in the IC rate in CRC programmes. To ensure comparability between programmes, there is a need for consensus on the working definition of IC and the methods used for their identification and quantification. Copyright © 2014 SESPAS. Published by Elsevier Espana. All rights reserved.

Fecal immunochemical tests in combination with blood tests for colorectal cancer and advanced adenoma detection—systematic review

PubMed Central

Niedermaier, Tobias; Weigl, Korbinian; Hoffmeister, Michael; Brenner, Hermann

2017-01-01

Background Colorectal cancer (CRC) is a common but largely preventable cancer. Although fecal immunochemical tests (FITs) detect the majority of CRCs, they miss some of the cancers and most advanced adenomas (AAs). The potential of blood tests in complementing FITs for the detection of CRC or AA has not yet been systematically investigated. Methods We conducted a systematic review of performance of FIT combined with an additional blood test for CRC and AA detection versus FIT alone. PubMed and Web of Science were searched until June 9, 2017. Results Some markers substantially increased sensitivity for CRC when combined with FIT, albeit typically at a major loss of specificity. For AA, no relevant increase in sensitivity could be achieved. Conclusion Combining FIT and blood tests might be a promising approach to enhance sensitivity of CRC screening, but comprehensive evaluation of promising marker combinations in screening populations is needed. PMID:29435309

Diagnostic accuracy of a two-item screen for drug use developed from the alcohol, smoking and substance involvement screening test (ASSIST).

PubMed

Tiet, Quyen Q; Leyva, Yani; Moos, Rudolf H; Smith, Brandy

2016-07-01

The Alcohol, Smoking and Substance Involvement Screening Test (ASSIST) is a screening instrument to detect substance use in primary care (PC). To screen for illicit substances (excluding tobacco and alcohol), the ASSIST consists of 8-57 questions and requires complicated scoring. To improve the efficiency of screening of drug misuse in PC, this study constructed and validated a two-item screen for drug use from the ASSIST. Guided by previous reviews, the ASSIST was revised. Patients were recruited in VA primary care clinics (N=1283). Half of the sample was used to develop the ASSIST-Drug; the other half was used to validate it. The Mini International Neuropsychiatric Interview (MINI) and the Inventory of Drug Use Consequences were the criterion measures. A brief, two-item ASSIST-Drug was constructed. Based on the development sample, the ASSIST-Drug was 94.1% sensitive and 89.6% specific for drug use disorders. Based on the validation sample, it was 95.4% sensitive and 87.8% specific. The ASSIST-Drug also had comparable sensitivity and specificity to identify drug use negative consequences, as well as for diverse subgroups of patients in terms of gender, age, race/ethnicity, marital status, educational levels, and post traumatic stress disorder status. The ASSIST-Drug may be a useful screening tool for PC settings. It is reliable, brief, and easy to remember, administer and score. It is sensitive and specific for drug use disorders and drug use negative consequences, and the predictive properties are consistent across subgroup of patients. Published by Elsevier Ireland Ltd.

Human papillomavirus DNA testing as an adjunct to cytology in cervical screening programs.

PubMed

Lörincz, Attila T; Richart, Ralph M

2003-08-01

Our objective was to review current large studies of human papillomavirus (HPV) DNA testing as an adjunct to the Papanicolaou test for cervical cancer screening programs. We analyzed 10 large screening studies that used the Hybrid Capture 2 test and 3 studies that used the polymerase chain reaction test in a manner that enabled reliable estimates of accuracy for detecting or predicting high-grade cervical intraepithelial neoplasia (CIN). Most studies allowed comparison of HPV DNA and Papanicolaou testing and estimates of the performance of Papanicolaou and HPV DNA as combined tests. The studies were selected on the basis of a sufficient number of cases of high-grade CIN and cancer to provide meaningful statistical values. Investigators had to demonstrate the ability to generate reasonably reliable Hybrid Capture 2 or polymerase chain reaction data that were either minimally biased by nature of study design or that permitted analytical techniques for addressing issues of study bias to be applied. Studies had to provide data for the calculation of test sensitivity, specificity, predictive values, odds ratios, relative risks, confidence intervals, and other relevant measures. Final data were abstracted directly from published articles or estimated from descriptive statistics presented in the articles. In some studies, new analyses were performed from raw data supplied by the principal investigators. We concluded that HPV DNA testing was a more sensitive indicator for prevalent high-grade CIN than either conventional or liquid cytology. A combination of HPV DNA and Papanicolaou testing had almost 100% sensitivity and negative predictive value. The specificity of the combined tests was slightly lower than the specificity of the Papanicolaou test alone, but this decrease could potentially be offset by greater protection from neoplastic progression and cost savings available from extended screening intervals. One "double-negative" HPV DNA and Papanicolaou test indicated better prognostic assurance against risk of future CIN 3 than 3 subsequent negative conventional Papanicolaou tests and may safely allow 3-year screening intervals for such low-risk women.

The use of transient evoked otoacoustic emissions as a hearing screen following grommet insertion.

PubMed

Dale, O T; McCann, L J; Thio, D; Wells, S C; Drysdale, A J

2011-07-01

This study aimed to evaluate the sensitivity of transient evoked otoacoustic emission testing as a screening tool for hearing loss in children, after grommet insertion. A prospective study was conducted of 48 children (91 ears) aged three to 16 years who had undergone grommet insertion for glue ear. At post-operative review, pure tone audiometry was performed followed by transient evoked otoacoustic emission testing. Outcomes for both tests, in each ear, were compared. The pure tone audiometry threshold was ≤ 20 dB in 85 ears (93.4 per cent), 25 dB in two ears (2.2 per cent) and ≥ 30 dB in four ears (4.4 per cent). Transient evoked otoacoustic emissions were detected in 69 ears (75.8 per cent). The sensitivity of transient evoked otoacoustic emission testing for detecting hearing loss was 100 per cent for ≥ 30 dB loss but only 66.7 per cent for ≥ 25 dB loss. Transient evoked otoacoustic emission testing offers a sensitive means of detecting hearing loss of ≥ 30 dB following grommet insertion in children. However, the use of such testing as a screening tool may miss some cases of mild hearing loss.

Determining the sensitivity of transrectal ultrasonography on a consecutive series of prostate cancers in a clinical and screening setting.

PubMed

Ciatto, Stefano; Bonardi, Rita; Lombardi, Claudio; Zappa, Marco; Gervasi, Ginetta

2002-01-01

To evaluate the sensitivity at transrectal ultrasonography (TRUS) for prostate cancer. A consecutive series of 170 prostate cancers identified by matching local cancer registry and TRUS archives at the Centro per lo Studio e la Prevenzione Oncologica of Florence. TRUS sensitivity was determined as the ratio of TRUS positive to total prostate cancers occurring at different intervals from TRUS date. Univariate and multivariate analyses of sensitivity determinants were performed. Sensitivity at 6 months, 1, 2 and 3 years after the test was 94.1% (95% CI, 90-98), 89.8% (95% CI, 85-95), 80.4% (95% CI, 74-87) and 74.1% (95% CI, 68-81%), respectively. A higher sensitivity (statistically significant) of TRUS was observed only if digital rectal examination was suspicious, whereas no association to sensitivity was observed for age, prostate-specific antigen or prostate-specific antigen density. The study provided a reliable estimate of TRUS sensitivity, particularly reliable being checked against a cancer registry: observed sensitivity was high, at least of the same magnitude of other cancer screening tests. TRUS, which is known to allow for considerable diagnostic anticipation and is more specific than prostate-specific antigen, might still be considered for its contribution to a screening approach.

[Comparison of eight screening tests for ant-HCV antibody].

PubMed

Deguchi, Matsuo; Kagita, Masanori; Yamashita, Naoko; Nakano, Takasi; Tahara, Kazuko; Asari, Seishi; Iwatani, Yoshinori

2002-09-01

We compared eight HCV screening tests for detection of anti-HCV antibody; Ortho Quick Chaser HCV Ab (QC), Ortho HCV Ab ELISA III (ELISA), Ortho HVC Ab PA test III (PA), Lumipulse II Ortho HCV (LUMI), IMx HCV.DAINAPACKII (IMx), ARCHITECT HCV (ARCH), Immucheck.F-HCV C50 Ab (Immu), RANREAM HCV Ab Ex II (RAN). Sera from six hundred patients were examined by these eight screening tests. The positive rates of the eight screening tests were from 9.0% to 13.2%. Forty-five sera showed discrepant results between the eight screening tests, and about half of them showed weak positive reaction and/or false positive. Twenty-five of the forty-five sera were negative for ant-HCV antibody in the CHIRON RIBA III confirmatory test, and forty-four of them were negative for HCV-RNA in the PCR method. The agreement rates between the two reagents were from 95.5% to 99.2%, but were not always high between the two reagents that used similar antigen. The specificities and sensitivities evaluated by using the RIBA III confirmatory test were excellent in ELISA, LUMI, IMx, ARCH and Immu. Three BBI seroconversion panels were used to compare the positive readings in the initial stage of HCV infection by eight screening tests. ELISA and ARCH showed the earliest positive readings, and then IMx, LUMI = RAN, PA, QC and Immu in this order. These findings indicate that ELISA and ARCH were the most excellent in the sensitivity, specificity and early diagnosis of HCV infection. However, we must pay attention to the weak positive reaction in the screening tests, because there is a possibility of "false positive".

Controversies in colorectal cancer screening.

PubMed

Pox, Christian P

2014-01-01

Colorectal cancer (CRC) is one of the most common cancers worldwide and a good candidate for screening programmes. However, there is controversy concerning which of the available screening tests should be used. There is general agreement that screening for CRC in the asymptomatic population should begin at the age of 50. Several different screening methods are available which can be separated into those that mainly detect cancers: faecal occult blood tests [guaiac (FOBT) and immunochemical (FIT)], genetic stool tests, blood tests and the M2-pyruvate kinase (M2-PK) test. Methods that detect cancers and polyps are colonoscopy, sigmoidoscopy, CT-colonography (CT-C) and colon capsule endoscopy. The only tests for which a reduction in CRC mortality compared to no screening have been proven in randomized trials are FOBT and sigmoidoscopy. Several trials suggest that FIT are superior to FOBT in terms of detection rates of cancers and advanced adenomas and possibly compliance. There is indirect evidence suggesting efficacy of colonoscopy as a screening test. The role of CT-C is controversial. There is data suggesting a good sensitivity for neoplasia >9 mm with a lower sensitivity for smaller neoplasia. However, radiation exposure is considered a major limitation in some countries. Unresolved questions include the lesion cut-off for referral to colonoscopy and work-up of extracolonic findings. For other methods, like genetic stool testing using newer markers, blood tests, capsule endoscopy and M2-PK, there is currently insufficient data on screening of the asymptomatic population. Key Messages: Colorectal screening is recommended and should be performed in the form of an organized programme. If detection of early-stage cancers is the aim of a screening programme, FIT seem to be superior to FOBT. If detection and removal of adenomas is the aim of a screening programme, endoscopic methods seem to be good alternatives. Sigmoidoscopy is easier to perform but will likely only have an effect on distal cancers. Colonoscopy is more invasive but enables inspection of the whole colon. The role of CT-C, capsule endoscopy, genetic stool tests, blood tests and M2-PK is currently unknown. © 2014 S. Karger AG, Basel.

Rural physicians' perspectives on cervical and breast cancer screening: a gender-based analysis.

PubMed

Ahmad, F; Stewart, D E; Cameron, J I; Hyman, I

2001-03-01

Several studies highlight the role of physicians in determining cervical and breast cancer screening rates, and some urban studies report higher screening rates by female physicians. Rural women in North America remain underscreened for breast and cervical cancers. This survey was conducted to determine if there were significant gender differences in practices and perceptions of barriers to breast and cervical cancer screening among rural family physicians in Ontario, Canada. One hundred ninety-one family physicians (response rate 53.1%) who practiced in rural areas, small towns, or small cities completed a mail questionnaire. The physicians' mean age was 44.4 years (SD 9.9), and mean number of years in practice was 16.6 years (SD 10.3). Over 90% of physicians reported that they were very likely to conduct a Pap test and clinical breast examination (CBE) during a periodic health examination, and they had high levels of confidence and comfort in performing these procedures. Male (68%) and female (32%) physicians were similar in their likelihood to conduct screening, levels of confidence and comfort, and knowledge of breast and cervical cancer screening guidelines. However, the self-reported screening rates for Pap tests and CBE performed during last year were higher for female than male physicians (p < 0.01). Male physicians reported they were asked more frequently by patients for a referral to another physician to perform Pap tests and CBE (p < 0.001). Also, male physicians perceived patients' embarrassment as a stronger barrier to performing Pap tests (p < 0.05) and CBE (p < 0.01) than female physicians. No gender differences were observed in screening rates or related barriers to mammography referrals. These findings suggest that physicians' gender plays a role in sex-sensitive examination, such as Pap tests and CBE. There is a need to facilitate physician-patient interactions for sex-sensitive cancer screening examinations by health education initiatives targeting male physicians and women themselves. The feasibility of providing sex-sensitive cancer screening examinations by a same-sex health provider should also be explored.

The Ideal Strategy for Cervical Cancer Screening in Japan: Result from the Fukui Cervical Cancer Screening Study.

PubMed

Kurokawa, T; Onuma, T; Shinagawa, A; Chino, Y; Kobayashi, M; Yoshida, Y

2018-05-16

The aims of the Fukui Cervical Cancer Screening (FCCS) study are to determine the frequency of women with high-risk HPV (hrHPV), whether HPV16 or HPV18 (HPV16/18), in the Japanese cancer screening population for the first time and to identify the best strategy for cervical cancer screening in Japan. This study enrolled 7,584 women ≥25 years of age who were undergoing routine screening. All women underwent liquid-based cytology and cobas HPV tests. Women with abnormal cytology, whether hrHPV positive or negative; women with hrHPV positivity with either normal or abnormal cytology; and women randomly selected from women with normal cytology and negative hrHPV negative were referred for colposcopy. The prevalences of hrHPV positivity and HPV16/18 positivity were 6.8% and 1.7%, respectively. The baseline data from the FCCS study showed that the combination of HPV tests and cytology was more sensitive than cytology with respect to the detection of intraepithelial neoplasia grade 2 or worse. However, the specificity (94.1%) of the co-testing strategy that required all women with abnormal cytology or hrHPV positivity to be referred for colposcopy was much lower than that (97.8%) of cytology. The sensitivity and specificity of the co-testing strategy that required only women with abnormal cytology or HPV16/18 positivity to undergo colposcopy were 85.5% and 97.0%, respectively. The baseline data from the FCCS study suggest that a cervical cancer screening strategy in which only women with abnormal cytology or HPV16/18 positivity undergo colposcopy offers a more balanced sensitivity and specificity than other strategies. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Improved sensitivity of vaginal self-collection and high-risk human papillomavirus testing.

PubMed

Belinson, Jerome L; Du, Hui; Yang, Bin; Wu, Ruifang; Belinson, Suzanne E; Qu, Xinfeng; Pretorius, Robert G; Yi, Xin; Castle, Philip E

2012-04-15

Self-collected vaginal specimens tested for high-risk human papillomavirus (HR-HPV) have been shown to be less sensitive for the detection of cervical intraepithelial neoplasia or cancer (≥CIN 3) than physician-collected endocervical specimens. To increase the sensitivity of self-collected specimens, we studied a self-sampling device designed to obtain a larger specimen from the upper vagina (POI/NIH self-sampler) and a more sensitive polymerase chain reaction (PCR)-based HR-HPV assay. Women (10,000) were screened with cervical cytology and HR-HPV testing of vaginal self-collected and endocervical physician-collected specimens. Women were randomly assigned to use either a novel self-collection device (POI/NIH self-sampler) or conical-shaped brush (Qiagen). The self-collected and clinician-collected specimens were assayed by Cervista (Hologic) and the research only PCR-based matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF). Women with any abnormal screening test underwent colposcopy and biopsy. Women (8,556), mean age of 38.9, had complete data; 1.6% had ≥ CIN 3. For either HR-HPV assay, the sensitivity was similar for the two self-collection devices. Tested with Cervista, the sensitivity for ≥CIN 3 of self-collected specimens was 70.9% and for endocervical specimens was 95.0% (p = 0.0001). Tested with MALDI-TOF, the sensitivity for ≥CIN 3 of self-collected specimens was 94.3% and for endocervical specimens was also 94.3% (p = 1.0). A self-collected sample using a PCR-based assay with the capability of very high throughput has similar sensitivity as a direct endocervical specimen obtained by a physician. Large population-based screening "events" in low-resource settings could be achieved by promoting self-collection and centralized high-throughput, low-cost testing by PCR-based MALDI-TOF. Copyright © 2011 UICC.

Requirements for Minimum Sample Size for Sensitivity and Specificity Analysis

PubMed Central

Adnan, Tassha Hilda

2016-01-01

Sensitivity and specificity analysis is commonly used for screening and diagnostic tests. The main issue researchers face is to determine the sufficient sample sizes that are related with screening and diagnostic studies. Although the formula for sample size calculation is available but concerning majority of the researchers are not mathematicians or statisticians, hence, sample size calculation might not be easy for them. This review paper provides sample size tables with regards to sensitivity and specificity analysis. These tables were derived from formulation of sensitivity and specificity test using Power Analysis and Sample Size (PASS) software based on desired type I error, power and effect size. The approaches on how to use the tables were also discussed. PMID:27891446

Molecular testing for Lynch syndrome in people with colorectal cancer: systematic reviews and economic evaluation.

PubMed

Snowsill, Tristan; Coelho, Helen; Huxley, Nicola; Jones-Hughes, Tracey; Briscoe, Simon; Frayling, Ian M; Hyde, Chris

2017-09-01

Inherited mutations in deoxyribonucleic acid (DNA) mismatch repair (MMR) genes lead to an increased risk of colorectal cancer (CRC), gynaecological cancers and other cancers, known as Lynch syndrome (LS). Risk-reducing interventions can be offered to individuals with known LS-causing mutations. The mutations can be identified by comprehensive testing of the MMR genes, but this would be prohibitively expensive in the general population. Tumour-based tests - microsatellite instability (MSI) and MMR immunohistochemistry (IHC) - are used in CRC patients to identify individuals at high risk of LS for genetic testing. MLH1 (MutL homologue 1) promoter methylation and BRAF V600E testing can be conducted on tumour material to rule out certain sporadic cancers. To investigate whether testing for LS in CRC patients using MSI or IHC (with or without MLH1 promoter methylation testing and BRAF V600E testing) is clinically effective (in terms of identifying Lynch syndrome and improving outcomes for patients) and represents a cost-effective use of NHS resources. Systematic reviews were conducted of the published literature on diagnostic test accuracy studies of MSI and/or IHC testing for LS, end-to-end studies of screening for LS in CRC patients and economic evaluations of screening for LS in CRC patients. A model-based economic evaluation was conducted to extrapolate long-term outcomes from the results of the diagnostic test accuracy review. The model was extended from a model previously developed by the authors. Ten studies were identified that evaluated the diagnostic test accuracy of MSI and/or IHC testing for identifying LS in CRC patients. For MSI testing, sensitivity ranged from 66.7% to 100.0% and specificity ranged from 61.1% to 92.5%. For IHC, sensitivity ranged from 80.8% to 100.0% and specificity ranged from 80.5% to 91.9%. When tumours showing low levels of MSI were treated as a positive result, the sensitivity of MSI testing increased but specificity fell. No end-to-end studies of screening for LS in CRC patients were identified. Nine economic evaluations of screening for LS in CRC were identified. None of the included studies fully matched the decision problem and hence a new economic evaluation was required. The base-case results in the economic evaluation suggest that screening for LS in CRC patients using IHC, BRAF V600E and MLH1 promoter methylation testing would be cost-effective at a threshold of £20,000 per quality-adjusted life-year (QALY). The incremental cost-effectiveness ratio for this strategy was £11,008 per QALY compared with no screening. Screening without tumour tests is not predicted to be cost-effective. Most of the diagnostic test accuracy studies identified were rated as having a risk of bias or were conducted in unrepresentative samples. There was no direct evidence that screening improves long-term outcomes. No probabilistic sensitivity analysis was conducted. Systematic review evidence suggests that MSI- and IHC-based testing can be used to identify LS in CRC patients, although there was heterogeneity in the methods used in the studies identified and the results of the studies. There was no high-quality empirical evidence that screening improves long-term outcomes and so an evidence linkage approach using modelling was necessary. Key determinants of whether or not screening is cost-effective are the accuracy of tumour-based tests, CRC risk without surveillance, the number of relatives identified for cascade testing, colonoscopic surveillance effectiveness and the acceptance of genetic testing. Future work should investigate screening for more causes of hereditary CRC and screening for LS in endometrial cancer patients. This study is registered as PROSPERO CRD42016033879. The National Institute for Health Research Health Technology Assessment programme.

Test equality between two binary screening tests with a confirmatory procedure restricted on screen positives.

PubMed

Lui, Kung-Jong; Chang, Kuang-Chao

2015-01-01

In studies of screening accuracy, we may commonly encounter the data in which a confirmatory procedure is administered to only those subjects with screen positives for ethical concerns. We focus our discussion on simultaneously testing equality of sensitivity and specificity between two binary screening tests when only subjects with screen positives receive the confirmatory procedure. We develop four asymptotic test procedures and one exact test procedure. We derive sample size calculation formula for a desired power of detecting a difference at a given nominal [Formula: see text]-level. We employ Monte Carlo simulation to evaluate the performance of these test procedures and the accuracy of the sample size calculation formula developed here in a variety of situations. Finally, we use the data obtained from a study of the prostate-specific-antigen test and digital rectal examination test on 949 Black men to illustrate the practical use of these test procedures and the sample size calculation formula.

The CAST (Childhood Asperger Syndrome Test)

ERIC Educational Resources Information Center

Williams, Jo; Scott, Fiona; Stott, Carol; Allison, Carrie; Bolton, Patrick; Baron-Cohen, Simon; Brayne, Carol

2005-01-01

The Childhood Asperger Syndrome Test (CAST) is a parental questionnaire to screen for autism spectrum conditions. In this validation study, the CAST was distributed to 1925 children aged 5-11 in mainstream Cambridgeshire schools. A sample of participants received a full diagnostic assessment, conducted blind to screen status. The sensitivity of…

Prevalence of gestational diabetes mellitus based on various screening strategies in western Kenya: a prospective comparison of point of care diagnostic methods.

PubMed

Pastakia, Sonak D; Njuguna, Benson; Onyango, Beryl Ajwang'; Washington, Sierra; Christoffersen-Deb, Astrid; Kosgei, Wycliffe K; Saravanan, Ponnusamy

2017-07-14

Early diagnosis of gestational diabetes mellitus (GDM) is crucial to prevent short term delivery risks and long term effects such as cardiovascular and metabolic diseases in the mother and infant. Diagnosing GDM in Sub-Saharan Africa (SSA) however, remains sub-optimal due to associated logistical and cost barriers for resource-constrained populations. A cost-effective strategy to screen for GDM in such settings are therefore urgently required. We conducted this study to determine the prevalence of gestational diabetes mellitus (GDM) and assess utility of various GDM point of care (POC) screening strategies in a resource-constrained setting. Eligible women aged ≥18 years, and between 24 and 32 weeks of a singleton pregnancy, prospectively underwent testing over two days. On day 1, a POC 1-h 50 g glucose challenge test (GCT) and a POC glycated hemoglobin (HbA1c) was assessed. On day 2, fasting blood glucose, 1-h and 2-h 75 g oral glucose tolerance test (OGTT) were determined using both venous and POC tests, along with a venous HbA1c. The International Association of Diabetes in Pregnancy Study Group (IADPSG) criteria was used to diagnose GDM. GDM prevalence was reported with 95% confidence interval (CI). Specificity, sensitivity, positive predictive value, and negative predictive value of the various POC testing strategies were determined using IADPSG testing as the standard reference. Six hundred-sixteen eligible women completed testing procedures. GDM was diagnosed in 18 women, a prevalence of 2.9% (95% CI, 1.57% - 4.23%). Compared to IADPSG testing, POC IADPSG had a sensitivity and specificity of 55.6% and 90.6% respectively while that of POC 1-h 50 g GCT (using a diagnostic cut-off of ≥7.2 mmol/L [129.6 mg/dL]) was 55.6% and 63.9%. All other POC tests assessed showed poor sensitivity. POC screening strategies though feasible, showed poor sensitivity for GDM detection in our resource-constrained population of low GDM prevalence. Studies to identify sensitive and specific POC GDM screening strategies using adverse pregnancy outcomes as end points are required. Clinical trials.gov : NCT02978807 , Registered 29 November 2016.

Assessment of the influence of test characteristics on the clinical and cost impacts of methicillin-resistant Staphylococcus aureus screening programs in US hospitals.

PubMed

Olchanski, Natalia; Mathews, Charles; Fusfeld, Lauren; Jarvis, William

2011-03-01

To compare the impacts of different methicillin-resistant Staphylococcus aureus (MRSA) screening test options (eg, polymerase chain reaction [PCR], rapid culture) and program characteristics on the clinical outcomes and budget of a typical US hospital. We developed an Excel-based decision-analytic model, using published literature to calculate and compare hospital costs and MRSA infection rates for PCR- or culture-based MRSA screening and then used multivariate sensitivity analysis to evaluate key variables. Same-day PCR testing for a representative 370-bed teaching hospital in the United States was assessed in different populations (high-risk patients, intensive care unit [ICU] patients, or all patients) and compared with other test options. Different screening program populations (all patients, high-risk patients, ICU patients, or patients with previous MRSA colonization or infection only) represented a potential savings of $12,158-$76,624 per month over no program ($188,618). Analysis of multiple test options in high-risk population screening indicated that same-day PCR testing of high-risk patients resulted in fewer infections over 1,720 patient-days (2.9, compared with 3.5 for culture on selective media and 3.8 for culture on nonselective media) and the lowest total cost ($112,012). The costs of other testing approaches ranged from $113,742 to $123,065. Sensitivity analysis revealed that variations in transmission rate, conversion to infection, prevalence increases, and hospital size are important to determine program impact. Among test characteristics, turnaround time is highly influential. All screening options showed reductions in infection rates and cost impact improvement over no screening program. Among the options, same-day PCR testing for high-risk patients slightly edges out the others in terms of fewest infections and greatest potential cost savings.

Point-of-care C-reactive protein-based tuberculosis screening for people living with HIV: a diagnostic accuracy study.

PubMed

Yoon, Christina; Semitala, Fred C; Atuhumuza, Elly; Katende, Jane; Mwebe, Sandra; Asege, Lucy; Armstrong, Derek T; Andama, Alfred O; Dowdy, David W; Davis, J Luke; Huang, Laurence; Kamya, Moses; Cattamanchi, Adithya

2017-12-01

Symptom-based screening for tuberculosis is recommended for all people living with HIV. This recommendation results in unnecessary Xpert MTB/RIF testing in many individuals living in tuberculosis-endemic areas and thus poor implementation of intensified case finding and tuberculosis preventive therapy. Novel approaches to tuberculosis screening are needed to help achieve global targets for tuberculosis elimination. We assessed the performance of C-reactive protein (CRP) measured with a point-of-care assay as a screening tool for active pulmonary tuberculosis. For this prospective study, we enrolled adults (aged ≥18 years) living with HIV with CD4 cell count less than or equal to 350 cells per μL who were initiating antiretroviral therapy (ART) from two HIV/AIDS clinics in Uganda. CRP concentrations were measured at study entry with a point-of-care assay using whole blood obtained by fingerprick (concentration ≥10 mg/L defined as screen positive for tuberculosis). Sputum samples were collected for Xpert MTB/RIF testing and culture. We calculated the sensitivity and specificity of point-of-care CRP and WHO symptom-based screening in reference to culture results. We repeated the sensitivity analysis with Xpert MTB/RIF as the reference standard. Between July 8, 2013, and Dec 15, 2015, 1237 HIV-infected adults were enrolled and underwent point-of-care CRP testing. 60 (5%) patients with incomplete or contaminated cultures were excluded from the analysis. Of the remaining 1177 patients (median CD4 count 165 cells per μL [IQR 75-271]), 163 (14%) had culture-confirmed tuberculosis. Point-of-care CRP testing had 89% sensitivity (145 of 163, 95% CI 83-93) and 72% specificity (731 of 1014, 95% CI 69-75) for culture-confirmed tuberculosis. Compared with WHO symptom-based screening, point-of-care CRP testing had lower sensitivity (difference -7%, 95% CI -12 to -2; p=0·002) but substantially higher specificity (difference 58%, 95% CI 55 to 61; p<0·0001). When Xpert MTB/RIF results were used as the reference standard, sensitivity of point-of-care CRP and WHO symptom-based screening were similar (94% [79 of 84] vs 99% [83 of 84], respectively; difference -5%, 95% CI -12 to 2; p=0·10). The performance characteristics of CRP support its use as a tuberculosis screening test for people living with HIV with CD4 count less than or equal to 350 cells per μL who are initiating ART. HIV/AIDS programmes should consider point-of-care CRP-based tuberculosis screening to improve the efficiency of intensified case finding and increase uptake of tuberculosis preventive therapy. National Institutes of Health; President's Emergency Plan for AIDS Relief; University of California, San Francisco, Nina Ireland Program for Lung Health. Copyright © 2017 Elsevier Ltd. All rights reserved.

Replacing Alpha-Fetoprotein With Alpha-Fetoprotein-L3 Increases the Sensitivity of Prenatal Screening for Trisomy 21.

PubMed

Huai, Lei; Leng, Jianhang; Ma, Shenglin; Huang, Fang; Shen, Junya; Ding, Yu

This study aimed to investigate the serum concentration of alpha-fetoprotein (AFP)-L3 in midterm pregnancies and its potential application in prenatal trisomy screening. The serum samples from 27 women with trisomy 21 fetuses and 800 women with normal fetuses were examined to measure the concentrations of AFP, AFP-L3, human chorionic gonadotropin (hCG), unconjugated estriol (uE3), and inhibin-A. The screening results of various tests consisting of these markers were analyzed. In normal pregnancies within 15-20 weeks of gestation, the medians of serum AFP-L3 were 4.63, 5.70, 5.78, 6.58, 7.03, and 7.25 pg/mL. The median of AFP-L3 MoM in the trisomy 21 group was 0.46, which was significantly lower than the value of 1 in the normal group (P < 0.05). When using a cutoff value of 1/270, the sensitivity of the triple marker test (AFP, hCG, uE3) was improved from 74% to 81% by replacing AFP with AFP-L3, with the false-positive rate slightly increased from 5.4% to 6.8%. Similarly, the sensitivity of the quad marker test (AFP, hCG, uE3, inhibin-A) was improved from 81% to 89% by replacing AFP with AFP-L3, with the false-positive rate slightly increased from 4.6% to 5.6%. Serum AFP-L3 concentration increases along with more weeks of gestation in the midterm pregnancies. Trisomy 21 screening tests with AFP replaced by AFP-L3 have higher sensitivities at the expense of slightly increased false-positive rates. This improvement in screening may help to better prepare the parents and caregivers for the special needs of newborns with trisomy 21.

Testing the woman abuse screening tool to identify intimate partner violence in Indonesia.

PubMed

Iskandar, Livia; Braun, Kathryn L; Katz, Alan R

2015-04-01

Intimate Partner Violence (IPV) is a global public health problem. IPV prevalence in Indonesia has been estimated to be less than 1%, based on reported cases. It is likely that IPV prevalence is underreported in Indonesia, as it is in many other countries. Screening for IPV has been found to increase IPV identification, but no screening tools are in use in Indonesia. The aim of this study was to test the translated Woman Abuse Screening Tool (WAST) for detecting IPV in Indonesia. The WAST was tested against a diagnostic interview by a trained psychologist on 240 women attending two Primary Health Centers in Jakarta. IPV prevalence and the reliability, sensitivity, and specificity of the WAST were estimated. Prevalence of IPV by diagnostic interview was 36.3%, much higher than published estimates. The most common forms of IPV identified were psychological (85%) and physical abuse (24%). Internal reliability of the WAST was high (α = .801). A WAST score of 13 (out of 24) is the recommended cutoff for identifying IPV, but only 17% of the Indonesian sample scored 13 or higher. Test sensitivity of the WAST with a cutoff score of 13 was only 41.9%, with a specificity of 96.8%. With a cutoff score of 10, the sensitivity improved to 84.9%, while the specificity decreased to 61.0%. Use of the WAST with a cutoff score of 10 provides good sensitivity and reasonable specificity and would provide a much-needed screening tool for use in Indonesia. Although a lower cutoff would yield a greater proportion of false positives, most of the true cases would be identified, increasing the possibility that women experiencing abuse would receive needed assistance. © The Author(s) 2014.

The development and initial validation of a sensitive bedside cognitive screening test.

PubMed

Faust, D; Fogel, B S

1989-01-01

Brief bedside cognitive examinations such as the Mini-Mental State Examination are designed to detect delirium and dementia but not more subtle or delineated cognitive deficits. Formal neuropsychological evaluation provides greater sensitivity and detects a wider range of cognitive deficits but is too lengthy for efficient use at the bedside or in epidemiological studies. The authors developed the High Sensitivity Cognitive Screen (HSCS), a 20-minute interview-based test, to identify patients who show disorder on formal neuropsychological evaluation. An initial study demonstrated satisfactory test-retest and interrater reliability. The HSCS was then administered to 60 psychiatric and neurological patients with suspected cognitive deficits but without gross impairment, who also completed formal neuropsychological testing. Results of both tests were independently classified as either normal, borderline, or abnormal. The HSCS correctly classified 93% of patients across the normal-abnormal dichotomy and showed promise for characterizing the extent and severity of cognitive dysfunction.

A comparison of standard serological tests for the diagnosis of bovine brucellosis in Canada.

PubMed Central

Stemshorn, B W; Forbes, L B; Eaglesome, M D; Nielsen, K H; Robertson, F J; Samagh, B S

1985-01-01

Six agglutination and two complement fixation tests were compared with respect to specificity, sensitivity and relative sensitivity for the serodiagnosis of bovine brucellosis. Based on 1051 sera from brucellosis free herds, the specificity of the tests was 98.9% for the buffered plate antigen test (BPAT), 99.2% and 99.3% for the standard tube and plate agglutination tests (STAT and SPAT), respectively, and 99.8% for the 2-mercaptoethanol test (2MET). On this small sample, the rose bengal plate test (RBPT), card test (CARD) and the complement fixation test (CFT) correctly classed all sera as negative. On a sample of 167 culture positive cattle, the sensitivities of the tests were CFT: 79.0%, BPAT: 75.4, RBPT: 74.9%, CARD: 74.3%, SPAT: 73.1%, STAT: 68.9%, and 2MET: 59.9%. All tests combined detected only 82% of these infected cattle. Analysis of the relative sensitivity of the six agglutination tests gave the following ranking: BPAT greater than RBPT greater than CARD greater than SPAT greater than STAT. The 2MET ranked between the BPAT and RBPT or between the RBPT and CARD depending on the analysis used. The use of the BPAT as a screening test is recommended provided that a test of high specificity and sensitivity such as the CFT is used to confirm screening test reactions. PMID:4075239

Contribution of mammography to MRI screening in BRCA mutation carriers by BRCA status and age: individual patient data meta-analysis

PubMed Central

Phi, Xuan-Anh; Saadatmand, Sepideh; De Bock, Geertruida H; Warner, Ellen; Sardanelli, Francesco; Leach, Martin O; Riedl, Christopher C; Trop, Isabelle; Hooning, Maartje J; Mandel, Rodica; Santoro, Filippo; Kwan-Lim, Gek; Helbich, Thomas H; Tilanus-Linthorst, Madeleine MA; van den Heuvel, Edwin R; Houssami, Nehmat

2016-01-01

Background: We investigated the additional contribution of mammography to screening accuracy in BRCA1/2 mutation carriers screened with MRI at different ages using individual patient data from six high-risk screening trials. Methods: Sensitivity and specificity of MRI, mammography and the combination of these tests were compared stratified for BRCA mutation and age using generalised linear mixed models with random effect for studies. Number of screens needed (NSN) for additional mammography-only detected cancer was estimated. Results: In BRCA1/2 mutation carriers of all ages (BRCA1=1219 and BRCA2=732), adding mammography to MRI did not significantly increase screening sensitivity (increased by 3.9% in BRCA1 and 12.6% in BRCA2 mutation carriers, P>0.05). However, in women with BRCA2 mutation younger than 40 years, one-third of breast cancers were detected by mammography only. Number of screens needed for mammography to detect one breast cancer not detected by MRI was much higher for BRCA1 compared with BRCA2 mutation carriers at initial and repeat screening. Conclusions: Additional screening sensitivity from mammography above that from MRI is limited in BRCA1 mutation carriers, whereas mammography contributes to screening sensitivity in BRCA2 mutation carriers, especially those ⩽40 years. The evidence from our work highlights that a differential screening schedule by BRCA status is worth considering. PMID:26908327

Contribution of mammography to MRI screening in BRCA mutation carriers by BRCA status and age: individual patient data meta-analysis.

PubMed

Phi, Xuan-Anh; Saadatmand, Sepideh; De Bock, Geertruida H; Warner, Ellen; Sardanelli, Francesco; Leach, Martin O; Riedl, Christopher C; Trop, Isabelle; Hooning, Maartje J; Mandel, Rodica; Santoro, Filippo; Kwan-Lim, Gek; Helbich, Thomas H; Tilanus-Linthorst, Madeleine M A; van den Heuvel, Edwin R; Houssami, Nehmat

2016-03-15

We investigated the additional contribution of mammography to screening accuracy in BRCA1/2 mutation carriers screened with MRI at different ages using individual patient data from six high-risk screening trials. Sensitivity and specificity of MRI, mammography and the combination of these tests were compared stratified for BRCA mutation and age using generalised linear mixed models with random effect for studies. Number of screens needed (NSN) for additional mammography-only detected cancer was estimated. In BRCA1/2 mutation carriers of all ages (BRCA1 = 1,219 and BRCA2 = 732), adding mammography to MRI did not significantly increase screening sensitivity (increased by 3.9% in BRCA1 and 12.6% in BRCA2 mutation carriers, P > 0.05). However, in women with BRCA2 mutation younger than 40 years, one-third of breast cancers were detected by mammography only. Number of screens needed for mammography to detect one breast cancer not detected by MRI was much higher for BRCA1 compared with BRCA2 mutation carriers at initial and repeat screening. Additional screening sensitivity from mammography above that from MRI is limited in BRCA1 mutation carriers, whereas mammography contributes to screening sensitivity in BRCA2 mutation carriers, especially those ⩽ 40 years. The evidence from our work highlights that a differential screening schedule by BRCA status is worth considering.

The minimum test battery to screen for binocular vision anomalies: report 3 of the BAND study.

PubMed

Hussaindeen, Jameel Rizwana; Rakshit, Archayeeta; Singh, Neeraj Kumar; Swaminathan, Meenakshi; George, Ronnie; Kapur, Suman; Scheiman, Mitchell; Ramani, Krishna Kumar

2018-03-01

This study aims to report the minimum test battery needed to screen non-strabismic binocular vision anomalies (NSBVAs) in a community set-up. When large numbers are to be screened we aim to identify the most useful test battery when there is no opportunity for a more comprehensive and time-consuming clinical examination. The prevalence estimates and normative data for binocular vision parameters were estimated from the Binocular Vision Anomalies and Normative Data (BAND) study, following which cut-off estimates and receiver operating characteristic curves to identify the minimum test battery have been plotted. In the receiver operating characteristic phase of the study, children between nine and 17 years of age were screened in two schools in the rural arm using the minimum test battery, and the prevalence estimates with the minimum test battery were found. Receiver operating characteristic analyses revealed that near point of convergence with penlight and red filter (> 7.5 cm), monocular accommodative facility (< 10 cycles per minute), and the difference between near and distance phoria (> 1.25 prism dioptres) were significant factors with cut-off values for best sensitivity and specificity. This minimum test battery was applied to a cohort of 305 children. The mean (standard deviation) age of the subjects was 12.7 (two) years with 121 males and 184 females. Using the minimum battery of tests obtained through the receiver operating characteristic analyses, the prevalence of NSBVAs was found to be 26 per cent. Near point of convergence with penlight and red filter > 10 cm was found to have the highest sensitivity (80 per cent) and specificity (73 per cent) for the diagnosis of convergence insufficiency. For the diagnosis of accommodative infacility, monocular accommodative facility with a cut-off of less than seven cycles per minute was the best predictor for screening (92 per cent sensitivity and 90 per cent specificity). The minimum test battery of near point of convergence with penlight and red filter, difference between distance and near phoria, and monocular accommodative facility yield good sensitivity and specificity for diagnosis of NSBVAs in a community set-up. © 2017 Optometry Australia.

Brief assessment of food insecurity accurately identifies high-risk US adults.

PubMed

Gundersen, Craig; Engelhard, Emily E; Crumbaugh, Amy S; Seligman, Hilary K

2017-06-01

To facilitate the introduction of food insecurity screening into clinical settings, we examined the test performance of two-item screening questions for food insecurity against the US Department of Agriculture's Core Food Security Module. We examined sensitivity, specificity and accuracy of various two-item combinations of questions assessing food insecurity in the general population and high-risk population subgroups. 2013 Current Population Survey December Supplement, a population-based US survey. All survey participants from the general population and high-risk subgroups. The test characteristics of multiple two-item combinations of questions assessing food insecurity had adequate sensitivity (>97 %) and specificity (>70 %) for widespread adoption as clinical screening measures. We recommend two specific items for clinical screening programmes based on their widespread current use and high sensitivity for detecting food insecurity. These items query how often the household 'worried whether food would run out before we got money to buy more' and how often 'the food that we bought just didn't last and we didn't have money to get more'. The recommended items have sensitivity across high-risk population subgroups of ≥97 % and a specificity of ≥74 % for food insecurity.

Rapid cognitive screening in multiple sclerosis accomplished by the Free Recall and Recognition Test.

PubMed

Claesson, I M; Ytterberg, C; Johansson, S; Almkvist, O; von Koch, L

2007-03-01

This study sought to investigate the feasibility of the Free Recall and Recognition Test (FRRT) as a practical screening tool for cognitive impairment in multiple sclerosis (MS). Persons with MS (n = 227) were consecutively recruited and assessed with four cognitive tests; FRRT, Symbol Digit Modalities Test (SDMT), Paced Auditory Serial Addition Test (PASAT), and the Mini-Mental State Examination (MMSE). Disease severity was assessed by the Expanded Disability Status Scale (EDSS). The FRRT, which was completed by 99% of the cohort in approximately 5 minutes per assessment, correlated significantly with the other cognitive tests, as well as with the disease severity rating. A cut-off of 4 for the FRRT recall rendered 90% sensitivity and 25% specificity, and a cut-off of 4.2 for the FRRT recognition resulted in 70% sensitivity and 51% specificity. We conclude that the FRRT proved feasible as a practical screening tool for cognitive impairment in MS within a clinical setting.

SCIENTIFIC AND TECHNOLOGICAL SUPPORT ON IN VITRO ASSAYS FOR THE AGENCY'S ENDOCRINE DISRUPTOR SCREENING PROGRAM

EPA Science Inventory

In response to the 1996 legislative mandate for an endocrine screening and testing program, we are helping develop, standardize and validate relatively sensitive, robust and relatively simple methods for in vitro screening of chemicals that affect estrogen, and androgen function ...

The bimanual ovarian palpation examination in the Prostate, Lung, Colorectal and Ovarian cancer screening trial: Performance and complications.

PubMed

Doroudi, Maryam; Kramer, Barnett S; Pinsky, Paul F

2017-12-01

Objective To provide evidence about the performance characteristics and consequences of bimanual ovarian palpation. Setting and methods The Prostate, Lung, Colorectal and Ovarian cancer screening trial randomized 154,900 individuals to either an intervention or control arm. Enrolled eligible participants were aged 55-74, had no history of trial cancers, and no current treatment for cancer. Intervention arm women received CA-125 tests and transvaginal ultrasound. Bimanual ovarian palpation was offered annually during the first four years of the trial. Bimanual ovarian palpation-specific sensitivity and specificity were calculated, as were rates of diagnostic procedures and resulting complications following positive bimanual ovarian palpation screens. Results A total of 20,872 women received at least one bimanual ovarian palpation, with 50,498 total bimanual ovarian palpation examinations performed. The sensitivity and specificity of bimanual ovarian palpation were 5.1% (2/39) and 99.0% (49,957/50,459), respectively; no cases were detected by bimanual ovarian palpation alone. Rates for most follow-up procedures for abnormal results in women without ovarian cancer were higher among the group with another screening test positive, except for pelvic exam, where rates were similar. No complications were reported in the bimanual ovarian palpation-only positive group. Conclusion Low sensitivity of bimanual ovarian palpation alone and in combination with other tests argue against using bimanual ovarian palpation as a screening test for ovarian cancer in asymptomatic women.

Development of a test of suprathreshold acuity in noise in Brazilian Portuguese: a new method for hearing screening and surveillance.

PubMed

Vaez, Nara; Desgualdo-Pereira, Liliane; Paglialonga, Alessia

2014-01-01

This paper describes the development of a speech-in-noise test for hearing screening and surveillance in Brazilian Portuguese based on the evaluation of suprathreshold acuity performances. The SUN test (Speech Understanding in Noise) consists of a list of intervocalic consonants in noise presented in a multiple-choice paradigm by means of a touch screen. The test provides one out of three possible results: "a hearing check is recommended" (red light), "a hearing check would be advisable" (yellow light), and "no hearing difficulties" (green light) (Paglialonga et al., Comput. Biol. Med. 2014). This novel test was developed in a population of 30 normal hearing young adults and 101 adults with varying degrees of hearing impairment and handicap, including normal hearing. The test had 84% sensitivity and 76% specificity compared to conventional pure-tone screening and 83% sensitivity and 86% specificity to detect disabling hearing impairment. The test outcomes were in line with the degree of self-perceived hearing handicap. The results found here paralleled those reported in the literature for the SUN test and for conventional speech-in-noise measures. This study showed that the proposed test might be a viable method to identify individuals with hearing problems to be referred to further audiological assessment and intervention.

Clinical Validity of hearScreen™ Smartphone Hearing Screening for School Children.

PubMed

Mahomed-Asmail, Faheema; Swanepoel, De Wet; Eikelboom, Robert H; Myburgh, Hermanus C; Hall, James

2016-01-01

The study aimed to determine the validity of a smartphone hearing screening technology (hearScreen™) compared with conventional screening audiometry in terms of (1) sensitivity and specificity, (2) referral rate, and (3) test time. One thousand and seventy school-age children in grades 1 to 3 (8 ± 1.1 average years) were recruited from five public schools. Children were screened twice, once using conventional audiometry and once with the smartphone hearing screening. Screening was conducted in a counterbalanced sequence, alternating initial screen between conventional or smartphone hearing screening. No statistically significant difference in performance between techniques was noted, with smartphone screening demonstrating equivalent sensitivity (75.0%) and specificity (98.5%) to conventional screening audiometry. While referral rates were lower with the smartphone screening (3.2 vs. 4.6%), it was not significantly different (p > 0.05). Smartphone screening (hearScreen™) was 12.3% faster than conventional screening. Smartphone hearing screening using the hearScreen™ application is accurate and time efficient.

The inclusion of N-terminal pro-brain natriuretic peptide in a sensitive screening strategy for systemic sclerosis-related pulmonary arterial hypertension: a cohort study

PubMed Central

2013-01-01

Introduction Pulmonary arterial hypertension (PAH) is a major cause of mortality in systemic sclerosis (SSc). Screening guidelines for PAH recommend multiple investigations, including annual echocardiography, which together have low specificity and may not be cost-effective. We sought to evaluate the predictive accuracy of serum N-terminal pro-brain natriuretic peptide (NT-proBNP) in combination with pulmonary function tests (PFT) (‘proposed’ algorithm) in a screening algorithm for SSc-PAH. Methods We evaluated our proposed algorithm (PFT with NT-proBNP) on 49 consecutive SSc patients with suspected pulmonary hypertension undergoing right heart catherisation (RHC). The predictive accuracy of the proposed algorithm was compared with existing screening recommendations, and is presented as sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV). Results Overall, 27 patients were found to have pulmonary hypertension (PH) at RHC, while 22 had no PH. The sensitivity, specificity, PPV and NPV of the proposed algorithm for PAH was 94.1%, 54.5%, 61.5% and 92.3%, respectively; current European Society of Cardiology (ESC)/European Respiratory Society (ERS) guidelines achieved a sensitivity, specificity, PPV and NPV of 94.1%, 31.8%, 51.6% and 87.5%, respectively. In an alternate case scenario analysis, estimating a PAH prevalence of 10%, the proposed algorithm achieved a sensitivity, specificity, PPV and NPV for PAH of 94.1%, 54.5%, 18.7% and 98.8%, respectively. Conclusions The combination of NT-proBNP with PFT is a sensitive, yet simple and non-invasive, screening strategy for SSc-PAH. Patients with a positive screening result can be referred for echocardiography, and further confirmatory testing for PAH. In this way, it may be possible to shift the burden of routine screening away from echocardiography. The findings of this study should be confirmed in larger studies. PMID:24246100

Automatic detection of anomalies in screening mammograms

PubMed Central

2013-01-01

Background Diagnostic performance in breast screening programs may be influenced by the prior probability of disease. Since breast cancer incidence is roughly half a percent in the general population there is a large probability that the screening exam will be normal. That factor may contribute to false negatives. Screening programs typically exhibit about 83% sensitivity and 91% specificity. This investigation was undertaken to determine if a system could be developed to pre-sort screening-images into normal and suspicious bins based on their likelihood to contain disease. Wavelets were investigated as a method to parse the image data, potentially removing confounding information. The development of a classification system based on features extracted from wavelet transformed mammograms is reported. Methods In the multi-step procedure images were processed using 2D discrete wavelet transforms to create a set of maps at different size scales. Next, statistical features were computed from each map, and a subset of these features was the input for a concerted-effort set of naïve Bayesian classifiers. The classifier network was constructed to calculate the probability that the parent mammography image contained an abnormality. The abnormalities were not identified, nor were they regionalized. The algorithm was tested on two publicly available databases: the Digital Database for Screening Mammography (DDSM) and the Mammographic Images Analysis Society’s database (MIAS). These databases contain radiologist-verified images and feature common abnormalities including: spiculations, masses, geometric deformations and fibroid tissues. Results The classifier-network designs tested achieved sensitivities and specificities sufficient to be potentially useful in a clinical setting. This first series of tests identified networks with 100% sensitivity and up to 79% specificity for abnormalities. This performance significantly exceeds the mean sensitivity reported in literature for the unaided human expert. Conclusions Classifiers based on wavelet-derived features proved to be highly sensitive to a range of pathologies, as a result Type II errors were nearly eliminated. Pre-sorting the images changed the prior probability in the sorted database from 37% to 74%. PMID:24330643

Tension fracture of laminates for transport fuselage. Part 1: Material screening

NASA Technical Reports Server (NTRS)

Walker, T. H.; Avery, W. B.; Ilcewicz, L. B.; Poe, C. C., Jr.; Harris, C. E.

1992-01-01

Transport fuselage structures are designed to contain pressure following a large penetrating damage event. Application of composites to fuselage structures requires a data base and supporting analysis on tension damage tolerance. Tests with 430 fracture specimens were used to accomplish the following: (1) identify critical material and laminate variables affecting notch sensitivity, (2) evaluate composite failure criteria, and (3) recommend a screening test method. Variables studied included fiber type, matrix toughness, lamination manufacturing process, and intraply hybridization. The laminates found to have the lowest notch sensitivity were manufactured using automated tow placement. This suggests a possible relationship between the stress distribution and repeatable levels of material inhomogeneity that are larger than found in traditional tape laminates. Laminates with the highest notch sensitivity consisted of toughened matrix materials that were resistant to a splitting phenomena that reduces stress concentrations in load bearing plies. Parameters for conventional fracture criteria were found to increase with the crack length of the smallest notch sizes studied. Most materials and laminate combinations followed less than a square root singularity for the largest crack sizes studied. Specimen geometry, notch type, and notch size were evaluated in developing a screening test procedure. Results indicate that a range of notch sizes must be tested to determine notch sensitivity.

[Cost effectiveness of mass orthoptic screening in kindergarten for early detection of developmental vision disorders].

PubMed

König, H H; Barry, J C; Leidl, R; Zrenner, E

2000-04-01

Orthoptic screening in the kindergarten is one option to improve early detection of amblyopia in children aged 3 years. The purpose of this study was to analyse the cost-effectiveness of such a screening programme in Germany. Based on data from the literature and own experience gained from orthoptic screening in kindergarten a decision-analytic model was developed. According to the model, all children in kindergarten, aged 3 years, who had not been treated for amblyopia before, were subjected to an orthoptic examination. Non-cooperative children were reexamined in kindergarten after one year. Children with positive test results were examined by an ophthalmologist for diagnosis. Effects were measured by the number of newly diagnosed cases of amblyopia, non-obvious strabismus and amblyogenic refractive errors. Direct costs were estimated from a third-party payer perspective. The influence of uncertain model parameters was tested by sensitivity analysis. In the base analysis the cost per orthoptic screening test was DM 15.39. Examination by an ophthalmologist cost DM 71.20. The total cost of the screening programme in all German kindergartens was DM 6.1 million. With a 1.5% age-specific prevalence of undiagnosed cases, a sensitivity of 95% and a specificity of 98%, a total of 4,261 new cases would be detected. The cost-effectiveness ratio was DM 1,421 per case detected. Sensitivity analysis showed considerable influence of prevalence and specificity on the cost-effectiveness ratio. It was more cost-effective to re-screen non-cooperative children in kindergarten than to have them examined by an ophthalmologist straight-away. The decision-analytic model showed stable results which may serve as a basis for discussion on the implementation of orthoptic screening and for planning a field study.

Sensitivity and specificity of different methods for cystic fibrosis-related diabetes screening: is the oral glucose tolerance test still the standard?

PubMed

Mainguy, Catherine; Bellon, Gabriel; Delaup, Véronique; Ginoux, Tiphanie; Kassai-Koupai, Behrouz; Mazur, Stéphane; Rabilloud, Muriel; Remontet, Laurent; Reix, Philippe

2017-01-01

Cystic fibrosis-related diabetes (CFRD) is a late cystic fibrosis (CF)-associated comorbidity whose prevalence is increasing sharply lifelong. Guidelines for glucose metabolism (GM) monitoring rely on the oral glucose tolerance test (OGTT). However, this test is neither sensitive nor specific. The aim of this study was to compare sensitivity and specificity of different methods for GM monitoring in children and adolescents with CF. Continuous glucose monitoring system (CGMS), used as the reference method, was compared with the OGTT, intravenous glucose tolerance test (IGTT), homeostasis model assessment index of insulin resistance (HOMA-IR), homeostasis model assessment index of β-cell function (HOMA-%B) and glycated haemoglobin A1C. Patients were classified into three groups according to CGMS: normal glucose tolerance (NGT), impaired glucose tolerance (IGT) and diabetes mellitus (DM). Twenty-nine patients (median age: 13.1 years) were recruited. According to CGMS, 11 had DM, 12 IGT and six NGT, whereas OGTT identified three patients with DM and five with IGT. While 13 of 27 had insulin deficiency according to IGTT, there was 19 of 28 according to HOMA-%B. According to HOMA-IR, 12 of 28 had insulin resistance. HOMA-%B was the most sensitive method for CFRD screening [sensitivity 91% (95% CI), specificity 47% (95% CI) and negative predictive value 89% (95% CI)]. OGTT showed the weak capacity to diagnose DM in CF and should no longer be considered as the reference method for CFRD screening in patients with CF. In our study, HOMA-%B showed promising metrics for CFRD screening. Finally, CGMS revealed that pathological glucose excursions were frequent even early in life.

Laboratory screening markers in gastroenterology--state of the art.

PubMed

Kocna, Petr; Vanickova, Zdislava; Zima, Tomas

2013-06-01

Screening tests for gastrointestinal diseases acceptable for population with a high sensitivity and high specificity can now be offered by clinical laboratories. This paper summarizes major recent advances in this area of laboratory medicine. Relevant articles published within the last 5 years in the NLM (National Library of Medicine) PubMed - Medline database covering the three gastrointestinal diseases - colorectal cancer, coeliac disease, and atrophic gastritis were included for this overview. In Europe, colorectal cancer (CRCA) is the second most frequent malignant disease. Quantitative immunochemical analysis of the stool for haemoglobin provides the best screening test to date, with both sensitivity and specificity approaching 95%. Even though coeliac disease (CD) affects approximately 1% of the general population, it remains largely unrecognised. Recommended methods for screening currently involve the detection of IgA and IgG antibodies against tissue transglutaminase and deamidated gliadin peptide. Evaluations of screening are now discussed for other diseases of the gastrointestinal tract - such as chronic atrophic gastritis (CAG), and inflammatory bowel disease (IBD). Detection of infection by Helicobacter pylori and stomach-specific plasmatic biomarkers, especially pepsinogen I/II ratio, could help with the prevention of gastric carcinomas. The use of faecal calprotectin as a screening test could substantially reduce the number of invasive methods necessary for the diagnostic work-up of patients with IBD. Screening tests for CRCA and CD have been used worldwide for many years. Screening strategies for gastrointestinal diseases are suggested in the text, based on recent basic science, clinical papers as well as our own experience.

Correlation analysis of two serum-specific immunoglobulin E test systems and skin-prick test in allergic rhinitis patients from northeast China.

PubMed

Jiang, Xiao-Dan; Li, Guang-Yu; Dong, Zhen; Zhu, Dong-Dong

2011-01-01

Skin-prick testing (SPT) is the most common screening method for allergy evaluation. The detection of serum-specific immunoglobulin E (sIgE) is also commonly used. The sensitivity and specificity of these testing methods may vary due to type of causative allergen and type of allergic manifestation. The purpose of this study was to evaluate the correlation between two methods of measuring sIgE (AllergyScreen [Mediwiss Analytic GmbH, Moers, Germany] and ImmunoCAP [Pharmacia, Uppsala, Sweden]) and SPT for the diagnosis of allergic rhinitis (AR). All 216 patients who were referred to the allergist for suspected AR from June to October 2009 had SPT and the two serological tests. One hundred fifty-eight patients had a positive clinical history and a related positive SPT. The SPT was used as reference standard, and we selected three allergens (Dermatophagoides pteronyssinus, mugwort, and ragweed), which were common in fall in northeast China, to analyze the correlation of the two serum tests and SPT. Compared with the SPT, the diagnostic indexes (accuracy, sensitivity and specificity) of the AllergyScreen system and the ImmunoCAP system were 0.819 versus 0.810, 0.780 versus 0.872, and 0.862 versus 0.741, respectively. The accuracy was similar between the two systems (p > 0.05). The ImmunoCAP system method had a higher sensitivity (p < 0.01). The AllergyScreen system had a higher specificity (p < 0.01). These data support that the AllergyScreen system and ImmunoCAP system can identify potentially significant allergens in the diagnosis of AR in patients from northeastern China.

Risk-based screening for Chlamydia trachomatis and Neisseria gonorrhoeae prior to intrauterine device insertion.

PubMed

Grentzer, Jaclyn M; Peipert, Jeffrey F; Zhao, Qiuhong; McNicholas, Colleen; Secura, Gina M; Madden, Tessa

2015-10-01

The objective was to compare three strategies for Chlamydia trachomatis and Neisseria gonorrhoeae screening prior to intrauterine device (IUD) insertion. This was a secondary analysis of the Contraceptive CHOICE Project. We measured the prevalence of C. trachomatis and/or N. gonorrhoeae at the time of IUD insertion. We then compared sensitivity, specificity, negative and positive predictive values, and likelihood ratios for three screening strategies for C. trachomatis and N. gonorrhoeae prior to IUD insertion: (a) "age-based" — age ≤25 years alone; (b) "age/partner-based" — age ≤25 and/or multiple sexual partners; and (c) "risk-based" — age ≤25, multiple sexual partners, inconsistent condom use and/or history of prior sexually transmitted infection (STI). Among 5087 IUD users, 140 (2.8%) tested positive for C. trachomatis, 16 (0.3%) tested positive for N. gonorrhoeae, and 6 (0.1%) were positive for both at the time of IUD insertion. The "risk-based" screening strategy had the highest sensitivity (99.3%) compared to "age-based" and "age/partner-based" screening (80.7% and 84.7%, respectively.) Only one (0.7%) woman with a chlamydia or gonorrhea infection would not have been screened using "risk-based" screening. A risk-based strategy to screen for C. trachomatis and N. gonorrhoeae prior to IUD insertion has higher sensitivity than screening based on age alone or age and multiple sexual partners. Using a risk-based screening strategy (age≤25, multiple sexual partners, inconsistent condom use and/or history of an STI) to determine who should be screened for C. trachomatis and N. gonorrhoeae prior to IUD insertion will miss very few cases of infection and obviates the need for universal screening. Copyright © 2015 Elsevier Inc. All rights reserved.

A single-question screening test for drug use in primary care.

PubMed

Smith, Peter C; Schmidt, Susan M; Allensworth-Davies, Donald; Saitz, Richard

2010-07-12

Drug use (illicit drug use and nonmedical use of prescription drugs) is common but underrecognized in primary care settings. We validated a single-question screening test for drug use and drug use disorders in primary care. Adult patients recruited from primary care waiting rooms were asked the single screening question, "How many times in the past year have you used an illegal drug or used a prescription medication for nonmedical reasons?" A response of at least 1 time was considered positive for drug use. They were also asked the 10-item Drug Abuse Screening Test (DAST-10). The reference standard was the presence or absence of current (past year) drug use or a drug use disorder (abuse or dependence) as determined by a standardized diagnostic interview. Drug use was also determined by oral fluid testing for common drugs of abuse. Of 394 eligible primary care patients, 286 (73%) completed the interview. The single screening question was 100% sensitive (95% confidence interval [CI], 90.6%-100%) and 73.5% specific (95% CI, 67.7%-78.6%) for the detection of a drug use disorder. It was less sensitive for the detection of self-reported current drug use (92.9%; 95% CI, 86.1%-96.5%) and drug use detected by oral fluid testing or self-report (81.8%; 95% CI, 72.5%-88.5%). Test characteristics were similar to those of the DAST-10 and were affected very little by participant demographic characteristics. The single screening question accurately identified drug use in this sample of primary care patients, supporting the usefulness of this brief screen in primary care.

Primary Screening for Cervical Cancer Based on High-Risk Human Papillomavirus (HPV) Detection and HPV 16 and HPV 18 Genotyping, in Comparison to Cytology

PubMed Central

Constantinidis, Theocharis; Constantinidis, Theodoros C.

2015-01-01

Objectives The objective of the present study is to assess the performance of a high-risk human papillomavirus (HR-HPV) DNA test with individual HPV-16/HPV-18 genotyping as a method for primary cervical cancer screening compared with liquid-based cytology (LBC) in a population of Greek women taking part in routine cervical cancer screening. Methods The study, conducted by the “HEllenic Real life Multicentric cErvical Screening” (HERMES) study group, involved the recruitment of 4,009 women, aged 25–55, who took part in routine cervical screening at nine Gynecology Departments in Greece. At first visit cervical specimens were collected for LBC and HPV testing using the Roche Cobas 4800 system. Women found positive for either cytology or HPV were referred for colposcopy, whereas women negative for both tests will be retested after three years. The study is ongoing and the results of the first screening round are reported herein. Results Valid results for cytology and HPV testing were obtained for 3,993 women. The overall prevalence of HR-HPV was 12.7%, of HPV-16 2.7% and of HPV-18 1.4%. Of those referred for colposcopy, cervical intraepithelial neoplasia grade 2 or worse (CIN2+) was detected in 41 women (1.07%). At the threshold of CIN2+, cytology [atypical squamous cells of undetermined significance (ASC-US) or worse] and HPV testing showed a sensitivity of 53.7% and 100% respectively, without change between age groups. Cytology and HPV testing showed specificity of 96.8% and 90.3% respectively, which was increased in older women (≥30) in comparison to younger ones (25–29). Genotyping for HPV16/18 had similar accuracy to cytology for the detection of CIN2+ (sensitivity: 58.5%; specificity 97.5%) as well as for triage to colposcopy (sensitivity: 58.5% vs 53.7% for cytology). Conclusion HPV testing has much better sensitivity than cytology to identify high-grade cervical lesions with slightly lower specificity. HPV testing with individual HPV-16/HPV-18 genotyping could represent a more accurate methodology for primary cervical cancer screening in comparison to liquid-based cytology, especially in older women. PMID:25793281

A Clinical Study of Subtype-based Prevalence of Dry Eye.

PubMed

Rege, Aditya; Kulkarni, Varsha; Puthran, Neelam; Khandgave, Tejaswini

2013-10-01

Dry Eye is a multifactorial disease of the tearfilm and the ocular surface which may be due to reduced tear production or excessive tear evaporation resulting in discomfort, visual disturbance, and tear film instability with a potential damage to the ocular surface. Various population-based studies have been done to find out the prevalence and the magnitude of the problem. Women Health Study reported prevalence of 7.8% after screening 36995 subjects above 49 years by interview. The prevalence reported by Blue Mountain Study was 15.3% .The Beaver Dam Study and Shiphai Eye studies are other studies reporting prevalence of 14.5% and 33.7% respectively. McMonnies questionnaire is a widely used screening instrument for Dry-Eye syndromes with sensitivity reportedly varying between 87% and 98% and specificity between 87% and 97%. Prevalence studies use McMonnie's questionnaire for screening individuals for Dry Eye, whereafter tests like Schirmer's test, Tear Film Break Up Time test, Rose Bengal test, Lissamine Green test and Meibomian Gland Dysfunction test are useful for further evaluation. While these tests help to differentiate the subtypes of Dry Eye such as Lipid Anomaly Dry Eye, Aqueous Tear Deficiency and Mucin Layer Deficiency, however, their sensitivity and specificity has not been widely studied. Additionally, very few studies have reported the prevalence of the various subtypes of Dry Eye. To determine the subtype-based prevalence of Dry Eye, to study the specificity and sensitivity of clinical tests for Dry Eye and to correlate McMonnies questionnaire with Dry Eye tests results. A prospective, cross-sectional, observational study, duly approved by the Institutional Ethics Committee, was conducted from October 2010 to April 2012. A total of 4750 subjects above 18 yrs of age were screened by the McMonnies questionnaire. Respondents having a score greater than 14.5 were subjected to clinical Dry Eye tests. The data obtained was analyzed using chi-square test. p value < 0.005 was considered statistically significant.The specificity and sensitivity of each clinical test was calculated using Schirmer's test as gold standard. The prevalence of Dry Eye was 15.4%, with a female preponderance (p = 0.01) and a significant increase with age above 60 years was noted (p<0.0001). Tear Film Break Up Time was the most reliable test with a good sensitivity (68.85%) and specificity (78.32%). Lipid Anomaly Dry Eye was the most prevalent (14.48%) followed by Aqueous Tear Deficiency (13.36%) and Mucin Layer Deficiency (3.51%). A positive correlation between McMonnies score and severity of Dry Eye was seen. This study suggests that Lipid Layer Anomaly is the most prevalent subtype in Dry Eye. Tear Film Break Up Time test is the most likely test to diagnose mild Dry Eye. McMonies Questionnaire can be effectively used for screening of a large population. Tear Film Break Up Time was found to have better sensitivity as well as specificity than other tests used for diagnosing Dry Eye.

The efficacy and cost of alternative strategies for systematic screening for type 2 diabetes in the U.S. population 45-74 years of age.

PubMed

Johnson, Susan L; Tabaei, Bahman P; Herman, William H

2005-02-01

To simulate the outcomes of alternative strategies for screening the U.S. population 45-74 years of age for type 2 diabetes. We simulated screening with random plasma glucose (RPG) and cut points of 100, 130, and 160 mg/dl and a multivariate equation including RPG and other variables. Over 15 years, we simulated screening at intervals of 1, 3, and 5 years. All positive screening tests were followed by a diagnostic fasting plasma glucose or an oral glucose tolerance test. Outcomes include the numbers of false-negative, true-positive, and false-positive screening tests and the direct and indirect costs. At year 15, screening every 3 years with an RPG cut point of 100 mg/dl left 0.2 million false negatives, an RPG of 130 mg/dl or the equation left 1.3 million false negatives, and an RPG of 160 mg/dl left 2.8 million false negatives. Over 15 years, the absolute difference between the most sensitive and most specific screening strategy was 4.5 million true positives and 476 million false-positives. Strategies using RPG cut points of 130 mg/dl or the multivariate equation every 3 years identified 17.3 million true positives; however, the equation identified fewer false-positives. The total cost of the most sensitive screening strategy was $42.7 billion and that of the most specific strategy was $6.9 billion. Screening for type 2 diabetes every 3 years with an RPG cut point of 130 mg/dl or the multivariate equation provides good yield and minimizes false-positive screening tests and costs.

Screening for Dyslexia in French-Speaking University Students: An Evaluation of the Detection Accuracy of the Alouette Test.

PubMed

Cavalli, Eddy; Colé, Pascale; Leloup, Gilles; Poracchia-George, Florence; Sprenger-Charolles, Liliane; El Ahmadi, Abdessadek

Developmental dyslexia is a lifelong impairment affecting 5% to 10% of the population. In French-speaking countries, although a number of standardized tests for dyslexia in children are available, tools suitable to screen for dyslexia in adults are lacking. In this study, we administered the Alouette reading test to a normative sample of 164 French university students without dyslexia and a validation sample of 83 students with dyslexia. The Alouette reading test is designed to screen for dyslexia in children, since it taps skills that are typically deficient in dyslexia (i.e., phonological skills). However, the test's psychometric properties have not previously been available, and it is not standardized for adults. The results showed that, on the Alouette test, dyslexic readers were impaired on measures of accuracy, speed, and efficiency (accuracy/reading time). We also found significant correlations between the Alouette reading efficiency and phonological efficiency scores. Finally, in terms of the Alouette test, speed-accuracy trade-offs were found in both groups, and optimal cutoff scores were determined with receiver operator characteristic curves analysis, yielding excellent discriminatory power, with 83.1% sensitivity and 100% specificity for reading efficiency. Thus, this study supports the Alouette test as a sensitive and specific screening tool for adults with dyslexia.

Use of the Analysis of the Volatile Faecal Metabolome in Screening for Colorectal Cancer

PubMed Central

2015-01-01

Diagnosis of colorectal cancer is an invasive and expensive colonoscopy, which is usually carried out after a positive screening test. Unfortunately, existing screening tests lack specificity and sensitivity, hence many unnecessary colonoscopies are performed. Here we report on a potential new screening test for colorectal cancer based on the analysis of volatile organic compounds (VOCs) in the headspace of faecal samples. Faecal samples were obtained from subjects who had a positive faecal occult blood sample (FOBT). Subjects subsequently had colonoscopies performed to classify them into low risk (non-cancer) and high risk (colorectal cancer) groups. Volatile organic compounds were analysed by selected ion flow tube mass spectrometry (SIFT-MS) and then data were analysed using both univariate and multivariate statistical methods. Ions most likely from hydrogen sulphide, dimethyl sulphide and dimethyl disulphide are statistically significantly higher in samples from high risk rather than low risk subjects. Results using multivariate methods show that the test gives a correct classification of 75% with 78% specificity and 72% sensitivity on FOBT positive samples, offering a potentially effective alternative to FOBT. PMID:26086914

Usefulness of enzyme immunoassay (EIA) for screening of anti HIV antibodies in urinary specimens: A comparative analysis.

PubMed

Sahni, A K; Nagendra, A; Roy, Partha; Patrikar, S

2014-07-01

Standard HIV testing is done using serum or plasma. FDA approved ELISA to screen urine for IgG antibodies to HIV-1 in 1996. It is a simple, noninvasive test and is appropriate for developing countries where health care personnel may not be professionally trained or where clean needles for drawing blood may not always be available. 436 individuals with high-risk behavior and strong clinical suspicion of HIV infection were screened for IgG antibodies to HIV-1 in urine by ELISA. Urine HIV testing was performed by enzyme immunoassay, at the ongoing Voluntary Confidential Counseling and Testing Center (VCCTC) at a large tertiary care microbiology lab. The individuals enrolled for the study had high-risk exposure to the virus and majorities were from a state with a high incidence of HIV infection. In all individuals, both serum and urine were tested for IgG antibodies to HIV-1. Overall, 135 individuals (30.96%) were HIV-positive, of whom 96 (71%) had never previously tested positive; 87% of those who tested positive received their results, and most were referred for medical care. Sensitivity, specificity and predictive values of HIV-1 urine ELISA test kit were determined. Sensitivity was found to be 89.6%; 95% CI [82.9-94.0], specificity 97.3%; 95% CI [94.6-98.8], positive predictive value 93.8%; 95% CI [87.8-97.1] and negative predictive value 95.4%; 95% CI [92.3-97.4]. Efficiency, sensitivity, and specificity of the urine-based screening for HIV-1 test kits were excellent as compared to the reference test.

Validation of a portable nitric oxide analyzer for screening in primary ciliary dyskinesias.

PubMed

Harris, Amanda; Bhullar, Esther; Gove, Kerry; Joslin, Rhiannon; Pelling, Jennifer; Evans, Hazel J; Walker, Woolf T; Lucas, Jane S

2014-02-10

Nasal nitric oxide (nNO) levels are very low in primary ciliary dyskinesia (PCD) and it is used as a screening test. We assessed the reliability and usability of a hand-held analyser in comparison to a stationary nitric oxide (NO) analyser in 50 participants (15 healthy, 13 PCD, 22 other respiratory diseases; age 6-79 years). Nasal NO was measured using a stationary NO analyser during a breath-holding maneuver, and using a hand-held analyser during tidal breathing, sampling at 2 ml/sec or 5 ml/sec. The three methods were compared for their specificity and sensitivity as a screen for PCD, their success rate in different age groups, within subject repeatability and acceptability. Correlation between methods was assessed. Valid nNO measurements were obtained in 94% of participants using the stationary analyser, 96% using the hand-held analyser at 5 ml/sec and 76% at 2 ml/sec. The hand-held device at 5 ml/sec had excellent sensitivity and specificity as a screening test for PCD during tidal breathing (cut-off of 30 nL/min,100% sensitivity, >95% specificity). The cut-off using the stationary analyser during breath-hold was 38 nL/min (100% sensitivity, 95% specificity). The stationary and hand-held analyser (5 ml/sec) showed reasonable within-subject repeatability(% coefficient of variation = 15). The hand-held NO analyser provides a promising screening tool for PCD.

Validation of Version 3.0 of the Breast Cancer Genetics Referral Screening Tool (B-RST™).

PubMed

Bellcross, Cecelia; Hermstad, April; Tallo, Christine; Stanislaw, Christine

2018-05-08

Despite increased awareness of hereditary breast and ovarian cancer among clinicians and the public, many BRCA1/2 mutation carriers remain unaware of their risk status. The Breast Cancer Genetics Referral Screening Tool (B-RST™) was created and validated to easily identify individuals at increased risk for hereditary breast and ovarian cancer for referral to cancer genetics services. The purpose of this study was to revise B-RST™ to maximize sensitivity against BRCA1/2 mutation status. We analyzed pedigrees of 277 individuals who had undergone BRCA1/2 testing to determine modifications to the B-RST™ 2.0 algorithm that would maximize sensitivity for mutations, while maintaining simplicity. We used McNemar's chi-square test to compare validation measures between the revised version (3.0) and the 2.0 version. Algorithmic changes made to B-RST™ 2.0 increased the sensitivity against BRCA1/2 mutation analysis from 71.1 to 94.0% (P < 0.0001). While specificity decreased, all screen-positive individuals were appropriate for cancer genetics referral, the primary purpose of the tool. Despite calls for BRCA1/2 population screening, there remains a critical need to identify those most at risk who should receive cancer genetics services. B-RST™ version 3.0 demonstrates high sensitivity for BRCA1/2 mutations, yet remains a simple and quick screening tool for at-risk individuals.

Towards Risk-Based Test Protocols: Estimating the Contribution of Intensive Testing to the UK Bovine Tuberculosis Problem

PubMed Central

van Dijk, Jan

2013-01-01

Eradicating disease from livestock populations involves the balancing act of removing sufficient numbers of diseased animals without removing too many healthy individuals in the process. As ever more tests for bovine tuberculosis (BTB) are carried out on the UK cattle herd, and each positive herd test triggers more testing, the question arises whether ‘false positive’ results contribute significantly to the measured BTB prevalence. Here, this question is explored using simple probabilistic models of test behaviour. When the screening test is applied to the average UK herd, the estimated proportion of test-associated false positive new outbreaks is highly sensitive to small fluctuations in screening test specificity. Estimations of this parameter should be updated as a priority. Once outbreaks have been confirmed in screening-test positive herds, the following rounds of intensive testing with more sensitive, albeit less specific, tests are highly likely to remove large numbers of false positive animals from herds. Despite this, it is unlikely that significantly more truly infected animals are removed. BTB test protocols should become based on quantified risk in order to prevent the needless slaughter of large numbers of healthy animals. PMID:23717517

Uptake of prenatal diagnostic testing and the effectiveness of prenatal screening for Down syndrome.

PubMed

Jaques, Alice M; Collins, Veronica R; Muggli, Evelyne E; Amor, David J; Francis, Ivan; Sheffield, Leslie J; Halliday, Jane L

2010-06-01

To map prenatal screening and diagnostic testing pathways in Victorian pregnant women during 2003 to 2004; measure the impact of prenatal diagnostic testing uptake on the effectiveness of prenatal screening for Down syndrome; and assess factors influencing uptake of diagnostic testing following screening. State-wide data collections of prenatal screening and diagnostic tests were linked to all Victorian births and pregnancy terminations for birth defects. Overall, 52% of women had a prenatal test (65 692/126 305); screening (44.9%), diagnostic testing (3.9%), or both (3.2%). Uptake of diagnostic testing was 71.4% (2390/3349) after an increased risk screen result, and 2.5% (1381/54 286) after a low risk result. Variation in uptake of diagnostic testing reduced the effectiveness of the screening program by 11.2%: from 87.4% (sensitivity - 125/143) to 76.2% (prenatal diagnoses of Down syndrome - 109/143). In both the increased and low risk groups, uptake was influenced by absolute numerical risk, as well as by the change in numerical risk from a priori risk. This comprehensive follow-up demonstrates clearly that numerical risk is being used to aid in decision making about confirmatory diagnostic testing. Collectively, these fundamental individual decisions will impact on the overall effectiveness of screening programmes for Down syndrome.

Sensitivity of fetal RHD screening for safe guidance of targeted anti-D immunoglobulin prophylaxis: prospective cohort study of a nationwide programme in the Netherlands.

PubMed

de Haas, Masja; Thurik, Florentine F; van der Ploeg, Catharina P B; Veldhuisen, Barbera; Hirschberg, Hoang; Soussan, Aicha Ait; Woortmeijer, Heleen; Abbink, Frithjofna; Page-Christiaens, Godelieve C M L; Scheffer, Peter G; Ellen van der Schoot, C

2016-11-07

 To determine the accuracy of non-invasive fetal testing for the RHD gene in week 27 of pregnancy as part of an antenatal screening programme to restrict anti-D immunoglobulin use to women carrying a child positive for RHD DESIGN:  Prospectively monitoring of fetal RHD testing accuracy compared with serological cord blood typing on introduction of the test. Fetal RHD testing was performed with a duplex real time quantitative polymerase chain reaction, with cell-free fetal DNA isolated from 1 mL of maternal plasma The study period was between 4 July 2011 and 7 October 2012. The proportion of women participating in screening was determined.  Nationwide screening programme, the Netherlands. Tests are performed in a centralised setting.  25 789 RhD negative pregnant women.  Sensitivity, specificity, false negative rate, and false positive rate of fetal RHD testing compared with serological cord blood typing; proportion of technical failures; and compliance to the screening programme.  A fetal RHD test result and serological cord blood result were available for 25 789 pregnancies. Sensitivity for detection of fetal RHD was 99.94% (95% confidence interval 99.89% to 99.97%) and specificity was 97.74% (97.43% to 98.02%). Nine false negative results for fetal RHD testing were registered (0.03%, 95% confidence interval 0.01% to 0.06%). In two cases these were due to technical failures. False positive fetal RHD testing results were registered for 225 samples (0.87%, 0.76% to 0.99%). Weak RhD expression was shown in 22 of these cases, justifying anti-D immunoglobulin use. The negative and positive predictive values were 99.91% (95% confidence interval 99.82% to 99.95%) and 98.60% (98.40% to 98.77%), respectively. More than 98% of the women participated in the screening programme.  Fetal RHD testing in week 27 of pregnancy as part of a national antenatal screening programme is highly reliable and can be used to target both antenatal and postnatal anti-D immunoglobulin use. 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.

Screening for Human Immunodeficiency Virus, Hepatitis B Virus, Hepatitis C Virus, and Treponema pallidum by Blood Testing Using a Bio-Flash Technology-Based Algorithm before Gastrointestinal Endoscopy

PubMed Central

Zhen, Chen; QuiuLi, Zhang; YuanQi, An; Casado, Verónica Vocero; Fan, Yuan

2016-01-01

Currently, conventional enzyme immunoassays which use manual gold immunoassays and colloidal tests (GICTs) are used as screening tools to detect Treponema pallidum (syphilis), hepatitis B virus (HBV), hepatitis C virus (HCV), human immunodeficiency virus type 1 (HIV-1), and HIV-2 in patients undergoing surgery. The present observational, cross-sectional study compared the sensitivity, specificity, and work flow characteristics of the conventional algorithm with manual GICTs with those of a newly proposed algorithm that uses the automated Bio-Flash technology as a screening tool in patients undergoing gastrointestinal (GI) endoscopy. A total of 956 patients were examined for the presence of serological markers of infection with HIV-1/2, HCV, HBV, and T. pallidum. The proposed algorithm with the Bio-Flash technology was superior for the detection of all markers (100.0% sensitivity and specificity for detection of anti-HIV and anti-HCV antibodies, HBV surface antigen [HBsAg], and T. pallidum) compared with the conventional algorithm based on the manual method (80.0% sensitivity and 98.6% specificity for the detection of anti-HIV, 75.0% sensitivity for the detection of anti-HCV, 94.7% sensitivity for the detection of HBsAg, and 100% specificity for the detection of anti-HCV and HBsAg) in these patients. The automated Bio-Flash technology-based screening algorithm also reduced the operation time by 85.0% (205 min) per day, saving up to 24 h/week. In conclusion, the use of the newly proposed screening algorithm based on the automated Bio-Flash technology can provide an advantage over the use of conventional algorithms based on manual methods for screening for HIV, HBV, HCV, and syphilis before GI endoscopy. PMID:27707942

Screening for Human Immunodeficiency Virus, Hepatitis B Virus, Hepatitis C Virus, and Treponema pallidum by Blood Testing Using a Bio-Flash Technology-Based Algorithm before Gastrointestinal Endoscopy.

PubMed

Jun, Zhou; Zhen, Chen; QuiuLi, Zhang; YuanQi, An; Casado, Verónica Vocero; Fan, Yuan

2016-12-01

Currently, conventional enzyme immunoassays which use manual gold immunoassays and colloidal tests (GICTs) are used as screening tools to detect Treponema pallidum (syphilis), hepatitis B virus (HBV), hepatitis C virus (HCV), human immunodeficiency virus type 1 (HIV-1), and HIV-2 in patients undergoing surgery. The present observational, cross-sectional study compared the sensitivity, specificity, and work flow characteristics of the conventional algorithm with manual GICTs with those of a newly proposed algorithm that uses the automated Bio-Flash technology as a screening tool in patients undergoing gastrointestinal (GI) endoscopy. A total of 956 patients were examined for the presence of serological markers of infection with HIV-1/2, HCV, HBV, and T. pallidum The proposed algorithm with the Bio-Flash technology was superior for the detection of all markers (100.0% sensitivity and specificity for detection of anti-HIV and anti-HCV antibodies, HBV surface antigen [HBsAg], and T. pallidum) compared with the conventional algorithm based on the manual method (80.0% sensitivity and 98.6% specificity for the detection of anti-HIV, 75.0% sensitivity for the detection of anti-HCV, 94.7% sensitivity for the detection of HBsAg, and 100% specificity for the detection of anti-HCV and HBsAg) in these patients. The automated Bio-Flash technology-based screening algorithm also reduced the operation time by 85.0% (205 min) per day, saving up to 24 h/week. In conclusion, the use of the newly proposed screening algorithm based on the automated Bio-Flash technology can provide an advantage over the use of conventional algorithms based on manual methods for screening for HIV, HBV, HCV, and syphilis before GI endoscopy. Copyright © 2016 Jun et al.

Maternal cfDNA screening for Down syndrome--a cost sensitivity analysis.

PubMed

Cuckle, Howard; Benn, Peter; Pergament, Eugene

2013-07-01

This study aimed to determine the principal factors contributing to the cost of avoiding a birth with Down syndrome by using cell-free DNA (cfDNA) to replace conventional screening. A range of unit costs were assigned to each item in the screening process. Detection rates were estimated by meta-analysis and modeling. The marginal cost associated with the detection of additional cases using cfDNA was estimated from the difference in average costs divided by the difference in detection. The main factor was the unit cost of cfDNA testing. For example, replacing a combined test costing $150 with 3% false-positive rate and invasive testing at $1000, by cfDNA tests at $2000, $1500, $1000, and $500, the marginal cost is $8.0, $5.8, $3.6, and $1.4m, respectively. Costs were lower when replacing a quadruple test and higher for a 5% false-positive rate, but the relative importance of cfDNA unit cost was unchanged. A contingent policy whereby 10% to 20% women were selected for cfDNA testing by conventional screening was considerably more cost-efficient. Costs were sensitive to cfDNA uptake. Universal cfDNA screening for Down syndrome will only become affordable by public health purchasers if costs fall substantially. Until this happens, the contingent use of cfDNA is recommended. © 2013 John Wiley & Sons, Ltd.

Cost effectiveness of fecal DNA screening for colorectal cancer: a systematic review and quality appraisal of the literature.

PubMed

Skally, Mairead; Hanly, Paul; Sharp, Linda

2013-06-01

Fecal DNA (fDNA) testing is a noninvasive potential alternative to current colorectal cancer screening tests. We conducted a systematic review and quality assessment of studies of cost-effectiveness of fDNA as a colorectal cancer screening tool (compared with no screening and other screening modalities), and identified key variables that impinged on cost-effectiveness. We searched MEDLINE, Embase, and the Centre for Reviews and Dissemination for cost-effectiveness studies of fDNA-based screening, published in English by September 2011. Studies that undertook an economic evaluation of fDNA, using either a cost-effectiveness or cost-utility analysis, compared with other relevant screening modalities and/or no screening were included. Additional inclusion criteria related to the presentation of data pertaining to model variables including time horizon, costs, fDNA performance characteristics, screening uptake, and comparators. A total of 369 articles were initially identified for review. After removing duplicates and applying inclusion and exclusion criteria, seven articles were included in the final review. Data was abstracted on key descriptor variables including screening scenarios, time horizon, costs, test performance characteristics, screening uptake, comparators, and incremental cost-effectiveness ratios. Quality assessment was undertaken using a standard checklist for economic evaluations. Studies cited by cost-effectiveness articles as the source of data on fDNA test performance characteristics were also reviewed. Seven cost-effectiveness studies were included, from the USA (4), Canada (1), Israel (1), and Taiwan (1). Markov models (5), a partially observable Markov decision process model (1) and MISCAN and SimCRC (1) microsimulation models were used. All studies took a third-party payer perspective and one included, in addition, a societal perspective. Comparator screening tests, screening intervals, and specific fDNA tests varied between studies. fDNA sensitivity and specificity parameters were derived from 12 research studies and one meta-analysis. Outcomes assessed were life-years gained and quality-adjusted life-years gained. fDNA was cost-effective when compared with no screening in six studies. Compared with other screening modalities, fDNA was not considered cost-effective in any of the base-case analyses: in five studies it was dominated by all alternatives considered. Sensitivity analyses identified cost, compliance, and test parameters as key influential parameters. In general, poor presentation of "study design" and "data collection" details lowered the quality of included articles. Although the literature searches were designed for high sensitivity, the possibility cannot be excluded that some eligible studies may have been missed. Reports (such as Health Technology Assessments produced by government agencies) and other forms of grey literature were excluded because they are difficult to identify systematically and/or may not report methods and results in sufficient detail for assessment. On the basis of the available (albeit limited) evidence, while fDNA is cost-effective when compared with no screening, it is currently dominated by most of the other available screening options. Cost and test performance appear to be the main influences on cost-effectiveness.

Pilot study analyzing automated ECG screening of hypertrophic cardiomyopathy.

PubMed

Campbell, Matthew J; Zhou, Xuefu; Han, Chia; Abrishami, Hedayat; Webster, Gregory; Miyake, Christina Y; Sower, Christopher T; Anderson, Jeffrey B; Knilans, Timothy K; Czosek, Richard J

2017-06-01

Hypertrophic cardiomyopathy (HCM) is one of the leading causes of sudden cardiac death in athletes. However, preparticipation ECG screening has often been criticized for failing to meet cost-effectiveness thresholds, in part because of high false-positive rates and the cost of ECG screening itself. The purpose of this study was to assess the testing characteristics of an automated ECG algorithm designed to screen for HCM in a multi-institutional pediatric cohort. ECGs from patients with HCM aged 12 to 20 years from 3 pediatric institutions were screened for ECG criteria for HCM using a previously described automated computer algorithm developed specifically for HCM ECG screening. The results were compared to a known healthy pediatric cohort. The studies then were read by trained electrophysiologists using standard ECG criteria and compared to the results of automated screening. One hundred twenty-eight ECGs from unique patients with phenotypic HCM were obtained and compared with 256 studies from healthy control patients matched in 2:1 fashion. When presented with the ECGs, the non-voltage-based algorithm resulted in 81.2% sensitivity and 90.7% specificity. A trained electrophysiologist read the same data according to the Seattle Criteria, with 71% sensitivity with 95.7% specificity. The sensitivity of screening as well as the components of the ECG screening itself varied by institution. This pilot study demonstrates a potential for automated ECG screening algorithms to detect HCM with testing characteristics similar to that of a trained electrophysiologist. In addition, there appear to be differences in ECG characteristics between patient populations, which may account for the difficulties in universal screening. Copyright © 2017 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.

Antioxidant capacity of human saliva and periodontal screening assessment in healthy adults.

PubMed

Tartaglia, Gianluca Martino; Gagliano, Nicoletta; Zarbin, Luca; Tolomeo, Giorgia; Sforza, Chiarella

2017-06-01

Saliva plays a pivotal role as an antioxidant system, and saliva antioxidant levels are reduced in patients with periodontal disease. Recently, a biochemical test able to determine saliva antioxidant levels was proposed as predictive for oral cavity diseases, but it was not clinically tested. In this preliminary study, we evaluated the relationships between Periodontal Screening and Recordings characteristics of patients and saliva antioxidant levels measures. Thirty-nine patients (12 men, 27 women; mean age, 46 years, SD 17) attending the dental hygiene unit of a Private Clinic underwent a Periodontal Screening and Recordings examination and a saliva antioxidant levels measurement using a biochemical commercial test. The results of the clinical periodontal examination were compared to those obtained by the saliva test. Approximately 70% of patients showed a low saliva antioxidant levels value, while the other patients had Optimal/Normal values. Thirteen patients (33%) resulted positive to Periodontal Screening and Recordings test. Using Periodontal Screening and Recordings values as gold standard, the saliva antioxidant levels test correctly classified 52.6% of patients; sensitivity was 84.6%, specificity was 36%. The saliva antioxidant levels test had a good sensitivity when compared to the gold standard; this finding corroborates the hypothesis that alterations of the oral antioxidant levels are related to periodontal disease. The reduced specificity shows that saliva antioxidant levels test could detect alterations predisposing to periodontal disease before clinically evident aspects. Copyright © 2017 Elsevier Ltd. All rights reserved.

An evaluation of a rapid real time polymerase chain reaction assay for detection of group B streptococcus as part of a neonatal group B streptococcus prevention strategy.

PubMed

Money, Deborah; Dobson, Simon; Cole, Lesley; Karacabeyli, Eda; Blondel-Hill, Edith; Milner, Ruth; Thomas, Eva

2008-09-01

To evaluate the sensitivity, specificity, and feasibility of a rapid real-time polymerase chain reaction (PCR) test for group B streptococcus (GBS) completed during labour, compared with the standard culture test performed at 35 to 37 weeks' gestation. Women presenting to the maternity unit for term vaginal delivery had two vaginal/rectal samples collected. One swab was tested using a rapid PCR method (IDI-Strep B, Infectio Diagnostic [IDI] Inc., Sainte-Foy QC ), and the other was cultured after enrichment (intrapartum culture). Comparisons were made between these results and those of a culture-based screen at 35 to 37 weeks' gestation. Of the 190 women enrolled, 85% had results of the standard screen at 35 to 37 weeks available for comparison. The sensitivity and specificity of the standard 35- to 37-week screen were 84.3% (95% confidence interval [CI], 71.4-93.0) and 93.2% (95% CI 86.5-97.2) respectively, whereas the sensitivity and specificity of the rapid PCR were 90.7% (95% CI 79.7-96.9) and 97.6% (95% CI 93.1-99.5), respectively. The median reporting time for the rapid PCR test was 99 minutes (range 50-255). Results were available more than four hours before delivery in 81% of cases. In this Canadian centre, a rapid PCR test done at the time of labour (IDI-Strep B) demonstrated high sensitivity and specificity, comparable to the 35- to 37-week screen. The time to reporting results was acceptably short, allowing for timely administration of intrapartum prophylactic antibiotics.

Unmet clinical needs in cervical cancer screening.

PubMed

Rao, Jianyu; Escobar-Hoyos, Luisa; Shroyer, Kenneth R

2016-01-01

Cancer rates worldwide are expected to increase disproportionally in coming decades relative to the projected increase in population, especially in the developing world. The general unavailability of the Pap test and the cost of the HPV test in the developing world have precluded the deployment of effective cervical cancer screening programs in many developing countries. Recent improvements in testing technology arise from a need to overcome the significant limitations of the Pap test and HPV test, but results require first-world technology and validation. Developing countries, where cervical cancer remains one of the most important causes of cancer death, have the greatest need for an affordable, easy-to-use, and highly reliable cancer screening method that can return a diagnosis through efficient laboratory analysis or, more easily, at a woman's point of care. While research, testing, and vaccine improvements in recent years continue to lower the incidence of cervical cancer in some developed countries such as the U.S., HPV testing research needs to do more than test for the presence of virus. The tests must determine the presence and progression of cervical disease. Tests should be more sensitive and specific than Pap tests and Pap-related tests, and should be accurate in more than 90 percent of cases. Tests also need to be low-cost, objective, and easy to perform so screening programs can be widely implemented in developing countries where the need for a better cervical cancer screening test is highest. Such tests may be available through the recent advances in specific biomarkers of cervical cancer and multiplex detection technologies. Development of the next generation of cervical cancer tests that are more specific, sensitive, and informative than the traditional Pap or HPV test will make a significant impact on the reduction of cervical cancer worldwide.

Screening for tinea unguium by Dermatophyte Test Strip.

PubMed

Tsunemi, Y; Takehara, K; Miura, Y; Nakagami, G; Sanada, H; Kawashima, M

2014-02-01

The direct microscopy, fungal culture and histopathology that are necessary for the definitive diagnosis of tinea unguium are disadvantageous in that detection sensitivity is affected by the level of skill of the person who performs the testing, and the procedures take a long time. The Dermatophyte Test Strip, which was developed recently, can simply and easily detect filamentous fungi in samples in a short time, and there are expectations for its use as a method for tinea unguium screening. With this in mind, we examined the detection capacity of the Dermatophyte Test Strip for tinea unguium. The presence or absence of fungal elements was judged by direct microscopy and Dermatophyte Test Strip in 165 nail samples obtained from residents in nursing homes for the elderly. Moreover, the minimum sample amount required for positive determination was estimated using 32 samples that showed positive results by Dermatophyte Test Strip. The Dermatophyte Test Strip showed 98% sensitivity, 78% specificity, 84·8% positive predictive value, 97% negative predictive value and a positive and negative concordance rate of 89·1%. The minimum sample amount required for positive determination was 0·002-0·722 mg. The Dermatophyte Test Strip showed very high sensitivity and negative predictive value, and was considered a potentially useful method for tinea unguium screening. Positive determination was considered to be possible with a sample amount of about 1 mg. © 2013 British Association of Dermatologists.

Evaluation of the Sensitivity and Specificity of the New Clinical Diagnostic and Classification Criteria for Kashin-Beck Disease, an Endemic Osteoarthritis, in China.

PubMed

Yu, Fang Fang; Ping, Zhi Guang; Yao, Chong; Wang, Zhi Wen; Wang, Fu Qi; Guo, Xiong

2017-02-01

This study aimed to evaluate the sensitivity and specificity of the new clinical diagnostic and classification criteria for Kashin-Beck disease (KBD) using six clinical markers: flexion of the distal part of fingers, deformed fingers, enlarged finger joints, shortened fingers, squat down, and dwarfism. One-third of the total population in Linyou County was sampled by stratified random sampling. The survey included baseline characteristics and clinical diagnoses, and the sensitivity and specificity of the new criteria was evaluated. We identified 3,459 KBD patients, of which 69 had early stage KBD, 1,952 had stage I, 1,132 had stage II, and 306 had stage III. A screening test classified enlarged finger joints as stage I KBD, with a sensitivity and specificity of 0.978 and 0.045, respectively. Shortened fingers were classified as stage II KBD, with a sensitivity and specificity of 0.969 and 0.844, respectively, and dwarfism was classified as stage III KBD with a sensitivity and specificity of 0.951 and 0.992, respectively. Serial screening test revealed that the new clinical classification of KBD classified stages I, II, and III KBD with sensitivities of 0.949, 0.945, and 0.925 and specificities of 0.967, 0.970, and 0.993, respectively. The screening tests revealed that enlarged finger joints, shortened fingers, and dwarfism were appropriate markers for the clinical diagnosis and classification of KBD with high sensitivity and specificity. Copyright © 2017 The Editorial Board of Biomedical and Environmental Sciences. Published by China CDC. All rights reserved.

Clinical evaluation of the vector algorithm for neonatal hearing screening using automated auditory brainstem response.

PubMed

Keohane, Bernie M; Mason, Steve M; Baguley, David M

2004-02-01

A novel auditory brainstem response (ABR) detection and scoring algorithm, entitled the Vector algorithm is described. An independent clinical evaluation of the algorithm using 464 tests (120 non-stimulated and 344 stimulated tests) on 60 infants, with a mean age of approximately 6.5 weeks, estimated test sensitivity greater than 0.99 and test specificity at 0.87 for one test. Specificity was estimated to be greater than 0.95 for a two stage screen. Test times were of the order of 1.5 minutes per ear for detection of an ABR and 4.5 minutes per ear in the absence of a clear response. The Vector algorithm is commercially available for both automated screening and threshold estimation in hearing screening devices.

Cost-Effectiveness of High-Risk Human Papillomavirus Testing With Messenger RNA Versus DNA Under United States Guidelines for Cervical Cancer Screening.

PubMed

Ting, Jie; Smith, Jennifer S; Myers, Evan R

2015-10-01

To compare the cost-effectiveness of high-risk human papillomavirus (hrHPV) testing using a hrHPV DNA and a hrHPV messenger RNA (mRNA) assay under current US cervical cancer screening guidelines. We constructed a Markov model for stochastic cost-effectiveness analysis using published data. We compared screening efficiency using DNA and mRNA testing for the following: (1) cotesting with cytology in women 30 to 65 years, and (2) triage of women with mild cervical cytological abnormalities (atypical squamous cells of undetermined significance [ASC-US]) in the United States. Screening end point is histologically confirmed high-grade lesions (cervical intraepithelial neoplasia grade 2, 3, or invasive cancer). Sensitivity and specificity estimates of DNA and mRNA testing to detect cervical intraepithelial neoplasia grade 2, 3, or invasive cancer were obtained from 2 published trials: the US Clinical Evaluation of APTIMA mRNA (CLEAR) study for ASC-US triage and the French APTIMA Screening Evaluation (FASE) study for cotesting. Costs of DNA and mRNA testing were assumed identical. Costs of screening, diagnosis, and treatment of cervical neoplasia and cancer were from previously published estimates, adjusted to 2012 US dollars. Inputs were modeled as distributions for Monte Carlo probabilistic sensitivity analysis. Model outcomes were costs per life-year saved for each strategy, discounted at 3% annually. For both cotesting and ASC-US triage, mRNA testing cost less than DNA testing, whereas life expectancies were widely overlapping. There was a 100% probability that DNA testing was not cost-effective at $100,000/life-year saved threshold for ASC-US triage and a 55% probability that DNA testing was not cost-effective at the same threshold for cotesting. Based on the available evidence, mRNA testing for cotesting or ASC-US triage is likely to be more efficient than DNA testing under current US cervical cancer screening guidelines.

[Analysis of tools, methods and results of toxicological screening for detection of drug abuse in Italian professional drivers].

PubMed

Rosso, G L

2013-01-01

Three years after a protocol agreement between the State and the Regions came into force in 2008 (drug testing at the workplace Law) a large number of studies have been conducted to analyse and test the efficacy of on-site screening tests for detection of drug consumption (opiates, cocaine, cannabinoids, amphetamine and methamphetamine, MDMA and methadone), which are frequently used by the occupational health physician, and also to present data resulting from workplace drug testing obtained during health surveillance programmes. The aim of the present study was to verify whether the features of sensitivity and specificity of the most common on-site testing ensure correct application of the provisions of current Italian legislation and also to analyse published studies showing the frequency of positive drug testing. A review of Italian and international literature was carried out aimed at identifying studies relating to: (1) performance of on-site screening tests frequently used by the occupational health physician, (2) prevalence of drug use/abuse among Italian public and commercial transport drivers. A comparison between the studies was then carried out. Several rapid on-site screening tests are commercially available (Italian law does not provide standards for the technical specifications of the tests), the sensitivity and specificity of which varies depending on the model and the substance tested. The sensitivity of these tools is poor when used for the detection of low concentrations of drugs and/or their metabolites in urine (close to the cut-off). Studies are lacking that compare on-site tests performed by the occupational health physician and confirmative tests in specialized laboratories (with particular regard to false positives found by the occupational health physician). The major studies in terms of methods and/or size reported a positive rate (confirmed at the first level) between 1.6% and 1.9%. The drugs most frequently used/abused were cannabis and cocaine. The performance of on-site screening tests (to detect psychotropic substances on urine matrix) and the methodology required by Italian law show that the aims of Italian workplace drug testing legislation have not been achieved The low positive rate observed in Italian studies could be due to an error in the first phase of screening performed by the occupational health physician.

The uriscreen test to detect significant asymptomatic bacteriuria during pregnancy.

PubMed

Teppa, Roberto J; Roberts, James M

2005-01-01

Asymptomatic bacteriuria (ASB) occurs in 2-11% of pregnancies and it is a clear predisposition to the development of acute pyelonephritis, which, in turn, poses risk to mother and fetus. Treatment of bacteriuria during pregnancy reduces the incidence of pyelonephritis. Therefore, it is recommended to screen for ASB at the first prenatal visit. The gold standard for detection of bacteriuria during pregnancy is urine culture, but this test is expensive, time-consuming, and labor-intensive. To determine the reliability of an enzymatic urine screening test (Uriscreen; Savyon Diagnostics, Ashdod, Israel) for detecting ASB in pregnancy. Catheterized urine samples were collected from 150 women who had routine prenatal screening for ASB. Patients with urinary symptoms, active vaginal bleeding, or who were previously on antibiotics therapy were excluded from the study. Sensitivity, specificity, and the positive and negative predictive values for the Uriscreen were estimated using urine culture as the criterion standard. Urine cultures were considered positive if they grew >10(5) colony-forming units of a single uropathogen. Twenty-eight women (18.7%) had urine culture results indicating significant bacteriuria, and 17 of these 28 specimens had positive enzyme activity. Of 122 samples with no growth, 109 had negative enzyme activity. Sensitivity, specificity, and positive and negative predictive values for the Uriscreen test were 60.7% (+/-18.1), 89.3% (+/-5.6), 56.6%, and 90.8%, respectively. The Uriscreen test had inadequate sensitivity for rapid screening of bacteriuria in pregnancy.

Efficacy and effectiveness of screen and treat policies in prevention of type 2 diabetes: systematic review and meta-analysis of screening tests and interventions.

PubMed

Barry, Eleanor; Roberts, Samantha; Oke, Jason; Vijayaraghavan, Shanti; Normansell, Rebecca; Greenhalgh, Trisha

2017-01-04

 To assess diagnostic accuracy of screening tests for pre-diabetes and efficacy of interventions (lifestyle or metformin) in preventing onset of type 2 diabetes in people with pre-diabetes.  Systematic review and meta-analysis.  Medline, PreMedline, and Embase. Study protocols and seminal papers were citation-tracked in Google Scholar to identify definitive trials and additional publications. Data on study design, methods, and findings were extracted onto Excel spreadsheets; a 20% sample was checked by a second researcher. Data extracted for screening tests included diagnostic accuracy and population prevalence. Two meta-analyses were performed, one summarising accuracy of screening tests (with the oral glucose tolerance test as the standard) for identification of pre-diabetes, and the other assessing relative risk of progression to type 2 diabetes after either lifestyle intervention or treatment with metformin.  Empirical studies evaluating accuracy of tests for identification of pre-diabetes. Interventions (randomised trials and interventional studies) with a control group in people identified through screening. No language restrictions.  2874 titles were scanned and 148 papers (covering 138 studies) reviewed in full. The final analysis included 49 studies of screening tests (five of which were prevalence studies) and 50 intervention trials. HbA 1c had a mean sensitivity of 0.49 (95% confidence interval 0.40 to 0.58) and specificity of 0.79 (0.73 to 0.84), for identification of pre-diabetes, though different studies used different cut-off values. Fasting plasma glucose had a mean sensitivity of 0.25 (0.19 to 0.32) and specificity of 0.94 (0.92 to 0.96). Different measures of glycaemic abnormality identified different subpopulations (for example, 47% : of people with abnormal HbA 1c had no other glycaemic abnormality). Lifestyle interventions were associated with a 36% (28% to 43%) reduction in relative risk of type 2 diabetes over six months to six years, attenuating to 20% (8% to 31%) at follow-up in the period after the trails.  HbA 1c is neither sensitive nor specific for detecting pre-diabetes; fasting glucose is specific but not sensitive. Interventions in people classified through screening as having pre-diabetes have some efficacy in preventing or delaying onset of type 2 diabetes in trial populations. As screening is inaccurate, many people will receives an incorrect diagnosis and be referred on for interventions while others will be falsely reassured and not offered the intervention. These findings suggest that "screen and treat" policies alone are unlikely to have substantial impact on the worsening epidemic of type 2 diabetes.  PROSPERO (No CRD42016042920). 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.

Tension fracture of laminates for transport fuselage. Part 1: Material screening

NASA Technical Reports Server (NTRS)

Walker, T. H.; Avery, W. B.; Ilcewicz, L. B.; Poe, C. C., Jr.; Harris, C. E.

1992-01-01

Transport fuselage structures are designed to contain pressure following a large penetrating damage event. Applications of composites to fuselage structures require a database and supporting analysis on tension damage tolerance. Tests with 430 fracture specimens were used to accomplish the following: (1) identify critical material and laminate variables affecting notch sensitivity; (2) evaluate composite failure criteria; and (3) recommend a screening test method. Variables studied included fiber type, matrix toughness, lamination manufacturing process, and intraply hybridization. The laminates found to have the lowest notch sensitivity were manufactured using automated tow placement. This suggests a possible relationship between the stress distribution and repeatable levels of material inhomogeneity that are larger than found in traditional tape laminates. Laminates with the highest notch sensitivity consisted of toughened matrix materials that were resistant to a splitting phenomena that reduces stress concentrations in major load bearing plies. Parameters for conventional fracture criteria were found to increase with crack length for the smallest notch sizes studied. Most material and laminate combinations followed less than a square root singularity for the largest crack sizes studied. Specimen geometry, notch type, and notch size were evaluated in developing a screening test procedure. Traitional methods of correcting for specimen finite width were found to be lacking. Results indicate that a range of notch sizes must be tested to determine notch sensitivity. Data for a single small notch size (0.25 in. diameter) was found to give no indication of the sensitivity of a particular material and laminate layup to larger notch sizes.

Evaluation of Five Chromogenic Agar Media and the Rosco Rapid Carb Screen Kit for Detection and Confirmation of Carbapenemase Production in Gram-Negative Bacilli

PubMed Central

Gilmour, Matthew W.; DeGagne, Pat; Nichol, Kim; Karlowsky, James A.

2014-01-01

An efficient workflow to screen for and confirm the presence of carbapenemase-producing Gram-negative bacilli was developed by evaluating five chromogenic screening agar media and two confirmatory assays, the Rapid Carb screen test (Rosco Diagnostica A/S, Taastrup, Denmark) and the modified Hodge test. A panel of 150 isolates was used, including 49 carbapenemase-producing isolates representing a variety of β-lactamase enzyme classes. An evaluation of analytical performance, assay cost, and turnaround time indicated that the preferred workflow (screening test followed by confirmatory testing) was the chromID Carba agar medium (bioMérieux, Marcy l'Étoile, France), followed by the Rapid Carb screen test, yielding a combined sensitivity of 89.8% and a specificity of 100%. As an optional component of the workflow, a determination of carbapenemase gene class via molecular means could be performed subsequent to confirmatory testing. PMID:25355764

Specificity and Sensitivity Ratios of the Pediatric Language Acquisition Screening Tool for Early Referral-Revised.

ERIC Educational Resources Information Center

Sherman, Tracy; Shulman, Brian B.

1999-01-01

This study examined test characteristics of the Pediatric Language Acquisition Screening Tool for Early Referral-Revised (PLASTER-R), a set of developmental questionnaires for children 3 to 60 months of age. The PLASTER-R was moderately to highly successful in identifying children within normal limits for language development. Test-retest…

Field performance of clinical case definitions for influenza screening during the 2009 pandemic.

PubMed

Chen, Shey-Ying; Chen, Yee-Chun; Chiang, Wen-Chu; Kung, Hsiang-Chi; King, Chwan-Chuen; Lai, Mei-Shu; Chie, Wei-Chu; Chen, Shyr-Chyr; Chen, Wen-Jone; Chang, Shan-Chwen

2012-11-01

The aim of this study was to assess the performance of 3 different influenza-like illness (ILI) case definitions, adopted by the European (European-CDC), USA (USA-CDC), and Taiwan Centers for Disease Prevention and Control (Taiwan-CDC), as screening tools for influenza during the 2009 H1N1 pandemic. From August 15 to 30, 2009, all emergency department patients with clinical symptoms or at epidemiologic risk for influenza were enrolled in an observational cohort study. Influenza diagnosis was established by positive rapid influenza diagnostic test or virus isolation. Sensitivity, specificity, positive predictive value, and negative predictive value of the European-, USA, and Taiwan-CDC ILI case definitions for screening were determined. A total of 870 patients were screened during the study period. Rapid influenza diagnostic test was positive in 315 patients, 273 (85.6%) of whom had fever duration less than 72 hours. Virus isolation identified 4 more patients with influenza A initially negative by rapid influenza diagnostic test. The mean (SD) age of these 319 patients was 24.3 (18.1) years. Of the 870 screened patients, 670 (77.0%), 476 (54.7%), and 325 (37.4%) met the European-, USA-, and Taiwan-CDC ILI case definition, respectively. Screening sensitivity was 95%, 77.7%, and 57.7% and specificity was 33.4%, 58.6%, and 74.4%, respectively. Differences in sensitivity and specificity between any 2 of the 3 groups were statistically significant (P < .05). First-line physicians should recognize the advantage and limitation of different ILI case definitions in influenza screening, especially confronted by pandemic or highly pathogenic avian influenza in the future. Copyright © 2012 Elsevier Inc. All rights reserved.

Human papillomavirus testing and liquid-based cytology: results at recruitment from the new technologies for cervical cancer randomized controlled trial.

PubMed

Ronco, Guglielmo; Segnan, Nereo; Giorgi-Rossi, Paolo; Zappa, Marco; Casadei, Gian Piero; Carozzi, Francesca; Dalla Palma, Paolo; Del Mistro, Annarosa; Folicaldi, Stefania; Gillio-Tos, Anna; Nardo, Gaetano; Naldoni, Carlo; Schincaglia, Patrizia; Zorzi, Manuel; Confortini, Massimo; Cuzick, Jack

2006-06-07

Although testing for human papillomavirus (HPV) has higher sensitivity and lower specificity than cytology alone for detecting cervical intraepithelial neoplasia (CIN), studies comparing conventional and liquid-based cytology have had conflicting results. In the first phase of a two-phase multicenter randomized controlled trial, women aged 35-60 years in the conventional arm (n = 16,658) were screened using conventional cytology, and women in the experimental arm (n = 16,706) had liquid-based cytology and were tested for high-risk HPV types using the Hybrid Capture 2 assay. Women in the conventional arm were referred to colposcopy with atypical cells of undetermined significance (ASCUS) or higher and those in the experimental arm were referred with ASCUS or higher cytology or with a positive (> or = 1 pg/mL) HPV test. Sensitivity and positive predictive value (PPV) for detection of cervical intraepithelial neoplasia grade 2 or higher (CIN2+) were calculated. The screening methods and referral criterion applied in the experimental arm had higher sensitivity than that in the conventional arm (relative sensitivity = 1.47; 95% confidence interval [CI] = 1.03 to 2.09) but a lower PPV (relative PPV = 0.40; 95% CI = 0.23 to 0.66). With HPV testing alone at > or = 1 pg/mL and at > or = 2 pg/mL, the gain in sensitivity compared with the conventional arm remained similar (relative sensitivity = 1.43, 95% CI = 1.00 to 2.04 and relative sensitivity = 1.41, 95% CI = 0.98 to 2.01, respectively) but PPV progressively improved (relative PPV = 0.58, 95% CI = 0.33 to 0.98 and relative PPV = 0.75, 95% CI = 0.45 and 1.27, respectively). Referral based on liquid-based cytology alone did not increase sensitivity compared with conventional cytology (relative sensitivity = 1.06; 95% CI = 0.72 to 1.55) but reduced PPV (relative PPV = 0.57; 95% CI = 0.39 to 0.82). HPV testing alone was more sensitive than conventional cytology among women 35-60 years old. Adding liquid-based cytology improved sensitivity only marginally but increased false-positives. HPV testing using Hybrid Capture 2 with a 2 pg/mL cutoff may be more appropriate than a 1 pg/mL cutoff for primary cervical cancer screening.

Response to Vicriviroc in Treatment-Experienced Subjects Using an Enhanced Sensitivity Co-receptor Tropism Assay: Reanalysis of AIDS Clinical Trials Group A5211

PubMed Central

Su, Zhaohui; Gulick, Roy M.; Krambrink, Amy; Coakley, Eoin; Hughes, Michael D.; Han, Dong; Flexner, Charles; Wilkin, Timothy J.; Skolnik, Paul R.; Greaves, Wayne L.; Kuritzkes, Daniel R.; Reeves, Jacqueline D.

2009-01-01

The enhanced sensitivity Trofile assay was used to re-test co-receptor usage at study screening and entry for the 118 ACTG A5211 treatment-experienced subjects who had CCR5-tropic (R5) virus by the original Trofile assay at study screening. Among 90 vicriviroc recipients, a significantly (P<0.001) greater mean reduction in HIV-1 RNA was observed in 72 subjects with R5 virus versus 15 subjects reclassified with dual/mixed-tropic viruses at screening: −1.11 vs. −0.09 (day 14), −1.91 vs. −0.57 (week 24) log10 copies/mL, respectively. Results suggest that the enhanced sensitivity assay is a better screening tool for determining patient eligibility for CCR5 antagonist therapy. PMID:19874179

Blinded Validation of Breath Biomarkers of Lung Cancer, a Potential Ancillary to Chest CT Screening

PubMed Central

Phillips, Michael; Bauer, Thomas L.; Cataneo, Renee N.; Lebauer, Cassie; Mundada, Mayur; Pass, Harvey I.; Ramakrishna, Naren; Rom, William N.; Vallières, Eric

2015-01-01

Background Breath volatile organic compounds (VOCs) have been reported as biomarkers of lung cancer, but it is not known if biomarkers identified in one group can identify disease in a separate independent cohort. Also, it is not known if combining breath biomarkers with chest CT has the potential to improve the sensitivity and specificity of lung cancer screening. Methods Model-building phase (unblinded): Breath VOCs were analyzed with gas chromatography mass spectrometry in 82 asymptomatic smokers having screening chest CT, 84 symptomatic high-risk subjects with a tissue diagnosis, 100 without a tissue diagnosis, and 35 healthy subjects. Multiple Monte Carlo simulations identified breath VOC mass ions with greater than random diagnostic accuracy for lung cancer, and these were combined in a multivariate predictive algorithm. Model-testing phase (blinded validation): We analyzed breath VOCs in an independent cohort of similar subjects (n = 70, 51, 75 and 19 respectively). The algorithm predicted discriminant function (DF) values in blinded replicate breath VOC samples analyzed independently at two laboratories (A and B). Outcome modeling: We modeled the expected effects of combining breath biomarkers with chest CT on the sensitivity and specificity of lung cancer screening. Results Unblinded model-building phase. The algorithm identified lung cancer with sensitivity 74.0%, specificity 70.7% and C-statistic 0.78. Blinded model-testing phase: The algorithm identified lung cancer at Laboratory A with sensitivity 68.0%, specificity 68.4%, C-statistic 0.71; and at Laboratory B with sensitivity 70.1%, specificity 68.0%, C-statistic 0.70, with linear correlation between replicates (r = 0.88). In a projected outcome model, breath biomarkers increased the sensitivity, specificity, and positive and negative predictive values of chest CT for lung cancer when the tests were combined in series or parallel. Conclusions Breath VOC mass ion biomarkers identified lung cancer in a separate independent cohort, in a blinded replicated study. Combining breath biomarkers with chest CT could potentially improve the sensitivity and specificity of lung cancer screening. Trial Registration ClinicalTrials.gov NCT00639067 PMID:26698306

Evaluation of a malarial antibody assay for use in the screening of blood and tissue products for clinical use.

PubMed

Kitchen, A D; Lowe, P H J; Lalloo, K; Chiodini, P L

2004-10-01

A new recombinant Plasmodium antigen enzyme immunoassay (EIA) for the detection of malarial antibodies was evaluated for the screening of 'malaria-risk' blood and tissue donations. A total of 13,269 donor and patient samples were tested by both the EIA and the standard diagnostic antibody immunofluorescence test (IFAT). A total of 114/138 (82.6%) samples from patients with P. falciparum and 11/13 (84.6%) samples from patients with P. vivax tested positive. A total of 714/13,053 (5.47%) samples from donors identified as 'malaria risk', owing to residency or travel, were reactive in the EIA. The assay is more sensitive than a previously implemented malarial antibody EIA (73% in acute P. falciparum and 56% in acute P. vivax infections). The sensitivity of this new EIA is comparable to that of the IFAT, and the specificity is sufficient to screen 'malaria-risk' donors.

Identification of dysphagia using the Toronto Bedside Swallowing Screening Test (TOR-BSST©): are 10 teaspoons of water necessary?

PubMed

Martino, Rosemary; Maki, Ellen; Diamant, Nicholas

2014-06-01

Dysphagia screening often includes administration of water. This study assessed the accuracy in identifying dysphagia with each additional teaspoon of water. The original research of the TOR-BSST(©) permitted this assessment. Trained nurses from acute and rehabilitation facilities prospectively administered the TOR-BSST(©) to 311 eligible stroke inpatients. A sensitivity analysis was conducted for the water item using 10 teaspoons plus a sip as the standard. The proportion of positive screenings was 59.2% in acute and 38.5% in rehabilitation. Of all four items that form the TOR-BSST(©), the water swallow item contributed to the identification of dysphagia in 42.7% in acute and 29.0% in rehabilitation patients. Across all patients, dysphagia accuracy was that five teaspoons resulted in a sensitivity of 79% (95% confidence interval [CI] = 70-86), eight a sensitivity of 92% (95% CI = 85-96) and 10 a sensitivity of 96% (95% CI = 90-99). Although a primary contributor, the water swallow item alone does not identify all patients with dysphagia. For a water swallow to accurately identify dysphagia, it is critical to administer 10 teaspoons. The TOR-BSST(©) water swallow item contributes largely to the total TOR-BSST(©)'s screening score and in making the test highly accurate and reliable.

A Targeted Swallow Screen for the Detection of Postoperative Dysphagia.

PubMed

Gee, Erica; Lancaster, Elizabeth; Meltzer, Jospeh; Mendelsohn, Abie H; Benharash, Peyman

2015-10-01

Postoperative dysphagia leads to aspiration pneumonia, prolonged hospital stay, and is associated with increased mortality. A simple and sensitive screening test to identify patients requiring objective dysphagia evaluation is presently lacking. In this study, we evaluated the efficacy of a novel targeted swallow screen evaluation. This was a prospective trial involving all adult patients who underwent elective cardiac surgery with cardiopulmonary bypass at our institution over an 8-week period. Within 24 hours of extubation and before the initiation of oral intake, all postsurgical patients were evaluated using the targeted swallow screen. A fiberoptic endoscopic evaluation of swallowing was requested for failed screenings. During the study, 50 postcardiac surgery patients were screened. Fifteen (30%) failed the targeted swallow screen, and ten of the fifteen (66%) failed the subsequent fiberoptic endoscopic evaluation of swallowing exam and were confirmed to have dysphagia. The screening test had 100 per cent sensitivity for detecting dysphagia in our patient population, and a specificity of 87.5 per cent. The overall incidence of dysphagia was 20 per cent. We have shown that a targeted swallow evaluation can efficiently screen patients during the postcardiac surgery period. Furthermore, we have shown that the true incidence of dysphagia after cardiac surgery is significantly higher than previously recognized in literature.

Development of a Test of Suprathreshold Acuity in Noise in Brazilian Portuguese: A New Method for Hearing Screening and Surveillance

PubMed Central

Vaez, Nara; Desgualdo-Pereira, Liliane; Paglialonga, Alessia

2014-01-01

This paper describes the development of a speech-in-noise test for hearing screening and surveillance in Brazilian Portuguese based on the evaluation of suprathreshold acuity performances. The SUN test (Speech Understanding in Noise) consists of a list of intervocalic consonants in noise presented in a multiple-choice paradigm by means of a touch screen. The test provides one out of three possible results: “a hearing check is recommended” (red light), “a hearing check would be advisable” (yellow light), and “no hearing difficulties” (green light) (Paglialonga et al., Comput. Biol. Med. 2014). This novel test was developed in a population of 30 normal hearing young adults and 101 adults with varying degrees of hearing impairment and handicap, including normal hearing. The test had 84% sensitivity and 76% specificity compared to conventional pure-tone screening and 83% sensitivity and 86% specificity to detect disabling hearing impairment. The test outcomes were in line with the degree of self-perceived hearing handicap. The results found here paralleled those reported in the literature for the SUN test and for conventional speech-in-noise measures. This study showed that the proposed test might be a viable method to identify individuals with hearing problems to be referred to further audiological assessment and intervention. PMID:25247181

Results obtained with a low cost software-based audiometer for hearing screening.

PubMed

Ferrari, Deborah Viviane; Lopez, Esteban Alejandro; Lopes, Andrea Cintra; Aiello, Camila Piccini; Jokura, Pricila Reis

2013-07-01

 The implementation of hearing screening programs can be facilitated by reducing operating costs, including the cost of equipment. The Telessaúde (TS) audiometer is a low-cost, software-based, and easy-to-use piece of equipment for conducting audiometric screening.  To evaluate the TS audiometer for conducting audiometric screening.  A prospective randomized study was performed. Sixty subjects, divided into those who did not have (group A, n = 30) and those who had otologic complaints (group B, n = 30), underwent audiometric screening with conventional and TS audiometers in a randomized order. Pure tones at 25 dB HL were presented at frequencies of 500, 1000, 2000, and 4000 Hz. A "fail" result was considered when the individual failed to respond to at least one of the stimuli. Pure-tone audiometry was also performed on all participants. The concordance of the results of screening with both audiometers was evaluated. The sensitivity, specificity, and positive and negative predictive values of screening with the TS audiometer were calculated.  For group A, 100% of the ears tested passed the screening. For group B, "pass" results were obtained in 34.2% (TS) and 38.3% (conventional) of the ears tested. The agreement between procedures (TS vs. conventional) ranged from 93% to 98%. For group B, screening with the TS audiometer showed 95.5% sensitivity, 90.4% sensitivity, and positive and negative predictive values equal to 94.9% and 91.5%, respectively.  The results of the TS audiometer were similar to those obtained with the conventional audiometer, indicating that the TS audiometer can be used for audiometric screening.

Looking ahead: a case for HPV testing of self-sampled vaginal specimens as a cervical cancer screening strategy

PubMed Central

Gravitt, Patti E.; Belinson, Jerome L.; Salmeron, Jorge; Shah, Keerti V.

2012-01-01

Even in the era of highly effective HPV prophylactic vaccines, substantial reduction in worldwide cervical cancer mortality will only be realized if effective early detection and treatment of the millions of women already infection and the millions who may not receive vaccination in the next decade can be broadly implemented through sustainable cervical cancer screening programs. Effective programs must meet three targets: 1) at least 70% of the targeted population should be screened at least once in a lifetime, 2) screening assays and diagnostic tests must be reproducible and sufficiently sensitive and specific for the detection of high-grade precursor lesions (i.e., CIN2+), and 3) effective treatment must be provided. We review the evidence that HPV DNA screening from swabs collected by the women in their home or village is sufficiently sound for consideration as a primary screening strategy in the developing world, with sensitivity and specificity for detection of CIN2+ as good or better than Pap smear cytology and VIA. A key feature of a self-collected HPV testing strategy (SC-HPV) is the move of the primary screening activities from the clinic to the community. Efforts to increase the affordability and availability of HPV DNA tests, community education and awareness, development of strong partnerships between community advocacy groups, health care centers and regional or local laboratories, and resource appropriate strategies to identify and treat screen-positive women should now be prioritized to ensure successful public health translation of the technologic advancements in cervical cancer prevention. PMID:21384341

The local lymph node assay and skin sensitization: a cut-down screen to reduce animal requirements?

PubMed

Kimber, Ian; Dearman, Rebecca J; Betts, Catherine J; Gerberick, G Frank; Ryan, Cindy A; Kern, Petra S; Patlewicz, Grace Y; Basketter, David A

2006-04-01

The local lymph node assay (LLNA), an alternative approach to skin-sensitizing testing, has made a significant contribution to animal welfare by permitting a reduction and refinement of animal use. Although there is clearly an aspiration to eliminate the use of animals in such tests, it is appropriate also to consider other opportunities for refinement and reduction of animal use. We have therefore explored the use of a modified version of the LLNA for screening purposes when there is a need to evaluate the sensitizing activity of a large number of chemicals, as will be the case under the auspices of registration, evaluation and authorization of chemicals (REACH). Using an existing LLNA database of 211 chemicals, we have examined whether a cut-down assay comprising a single high-dose group and a concurrent vehicle control would provide a realistic approach for screening chemicals for sensitizing potential. The analyses reported here suggest this is the case. We speculate that the animal welfare benefits may be enhanced further by reducing the number of animals per experimental group. However, a detailed evaluation will be necessary to provide reassurance that a reduction in group size would provide adequate sensitivity across a range of skin sensitization potencies.

[Implication of inverse-probability weighting method in the evaluation of diagnostic test with verification bias].

PubMed

Kang, Leni; Zhang, Shaokai; Zhao, Fanghui; Qiao, Youlin

2014-03-01

To evaluate and adjust the verification bias existed in the screening or diagnostic tests. Inverse-probability weighting method was used to adjust the sensitivity and specificity of the diagnostic tests, with an example of cervical cancer screening used to introduce the Compare Tests package in R software which could be implemented. Sensitivity and specificity calculated from the traditional method and maximum likelihood estimation method were compared to the results from Inverse-probability weighting method in the random-sampled example. The true sensitivity and specificity of the HPV self-sampling test were 83.53% (95%CI:74.23-89.93)and 85.86% (95%CI: 84.23-87.36). In the analysis of data with randomly missing verification by gold standard, the sensitivity and specificity calculated by traditional method were 90.48% (95%CI:80.74-95.56)and 71.96% (95%CI:68.71-75.00), respectively. The adjusted sensitivity and specificity under the use of Inverse-probability weighting method were 82.25% (95% CI:63.11-92.62) and 85.80% (95% CI: 85.09-86.47), respectively, whereas they were 80.13% (95%CI:66.81-93.46)and 85.80% (95%CI: 84.20-87.41) under the maximum likelihood estimation method. The inverse-probability weighting method could effectively adjust the sensitivity and specificity of a diagnostic test when verification bias existed, especially when complex sampling appeared.

Colorectal cancer screening: An updated review of the available options.

PubMed

Issa, Iyad A; Noureddine, Malak

2017-07-28

Colorectal cancer (CRC) is a significant cause of morbidity and mortality worldwide. However, colon cancer incidence and mortality is declining over the past decade owing to adoption of effective screening programs. Nevertheless, in some parts of the world, CRC incidence and mortality remain on the rise, likely due to factors including "westernized" diet, lifestyle, and lack of health-care infrastructure and resources. Participation and adherence to different national screening programs remain obstacles limiting the achievement of screening goals. Different modalities are available ranging from stool based tests to radiology and endoscopy with varying sensitivity and specificity. However, the availability of these tests is limited to areas with high economic resources. Recently, FDA approved a blood-based test (Epi procolon ® ) for CRC screening. This blood based test may serve to increase the participation and adherence rates. Hence, leading to increase in colon cancer detection and prevention. This article will discuss various CRC screening tests with a particular focus on the data regarding the new approved blood test. Finally, we will propose an algorithm for a simple cost-effective CRC screening program.

Colorectal cancer screening: An updated review of the available options

PubMed Central

Issa, Iyad A; Noureddine, Malak

2017-01-01

Colorectal cancer (CRC) is a significant cause of morbidity and mortality worldwide. However, colon cancer incidence and mortality is declining over the past decade owing to adoption of effective screening programs. Nevertheless, in some parts of the world, CRC incidence and mortality remain on the rise, likely due to factors including “westernized” diet, lifestyle, and lack of health-care infrastructure and resources. Participation and adherence to different national screening programs remain obstacles limiting the achievement of screening goals. Different modalities are available ranging from stool based tests to radiology and endoscopy with varying sensitivity and specificity. However, the availability of these tests is limited to areas with high economic resources. Recently, FDA approved a blood-based test (Epi procolon®) for CRC screening. This blood based test may serve to increase the participation and adherence rates. Hence, leading to increase in colon cancer detection and prevention. This article will discuss various CRC screening tests with a particular focus on the data regarding the new approved blood test. Finally, we will propose an algorithm for a simple cost-effective CRC screening program. PMID:28811705

The reliability and validity of using the urine dipstick test by patient self-assessment for urinary tract infection screening in spinal cord injury patients.

PubMed

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.

A framework provided an outline toward the proper evaluation of potential screening strategies.

PubMed

Adriaensen, Wim J; Matheï, Cathy; Buntinx, Frank J; Arbyn, Marc

2013-06-01

Screening tests are often introduced into clinical practice without proper evaluation, despite the increasing awareness that screening is a double-edged sword that can lead to either net benefits or harms. Our objective was to develop a comprehensive framework for the evaluation of new screening strategies. Elaborating on the existing concepts proposed by experts, a stepwise framework is proposed to evaluate whether a potential screening test can be introduced as a screening strategy into clinical practice. The principle of screening strategy evaluation is illustrated for cervical cancer, which is a template for screening because of the existence of an easily detectable and treatable precursor lesion. The evaluation procedure consists of six consecutive steps. In steps 1-4, the technical accuracy, place of the test in the screening pathway, diagnostic accuracy, and longitudinal sensitivity and specificity of the screening test are assessed. In steps 5 and 6, the impact of the screening strategy on the patient and population levels, respectively, is evaluated. The framework incorporates a harm and benefit trade-off and cost-effectiveness analysis. Our framework provides an outline toward the proper evaluation of potential screening strategies before considering implementation. Copyright © 2013 Elsevier Inc. All rights reserved.

Cost-effectiveness of Population Screening for BRCA Mutations in Ashkenazi Jewish Women Compared With Family History–Based Testing

PubMed Central

Manchanda, Ranjit; Legood, Rosa; Burnell, Matthew; McGuire, Alistair; Raikou, Maria; Loggenberg, Kelly; Wardle, Jane; Sanderson, Saskia; Gessler, Sue; Side, Lucy; Balogun, Nyala; Desai, Rakshit; Kumar, Ajith; Dorkins, Huw; Wallis, Yvonne; Chapman, Cyril; Taylor, Rohan; Jacobs, Chris; Tomlinson, Ian; Beller, Uziel; Menon, Usha

2015-01-01

Background: Population-based testing for BRCA1/2 mutations detects the high proportion of carriers not identified by cancer family history (FH)–based testing. We compared the cost-effectiveness of population-based BRCA testing with the standard FH-based approach in Ashkenazi Jewish (AJ) women. Methods: A decision-analytic model was developed to compare lifetime costs and effects amongst AJ women in the UK of BRCA founder-mutation testing amongst: 1) all women in the population age 30 years or older and 2) just those with a strong FH (≥10% mutation risk). The model assumes that BRCA carriers are offered risk-reducing salpingo-oophorectomy and annual MRI/mammography screening or risk-reducing mastectomy. Model probabilities utilize the Genetic Cancer Prediction through Population Screening trial/published literature to estimate total costs, effects in terms of quality-adjusted life-years (QALYs), cancer incidence, incremental cost-effectiveness ratio (ICER), and population impact. Costs are reported at 2010 prices. Costs/outcomes were discounted at 3.5%. We used deterministic/probabilistic sensitivity analysis (PSA) to evaluate model uncertainty. Results: Compared with FH-based testing, population-screening saved 0.090 more life-years and 0.101 more QALYs resulting in 33 days’ gain in life expectancy. Population screening was found to be cost saving with a baseline-discounted ICER of -£2079/QALY. Population-based screening lowered ovarian and breast cancer incidence by 0.34% and 0.62%. Assuming 71% testing uptake, this leads to 276 fewer ovarian and 508 fewer breast cancer cases. Overall, reduction in treatment costs led to a discounted cost savings of £3.7 million. Deterministic sensitivity analysis and 94% of simulations on PSA (threshold £20000) indicated that population screening is cost-effective, compared with current NHS policy. Conclusion: Population-based screening for BRCA mutations is highly cost-effective compared with an FH-based approach in AJ women age 30 years and older. PMID:25435542

Development and Validation of a P-35S, T-nos, T-35S and P-FMV Tetraplex Real-time PCR Screening Method to Detect Regulatory Genes of Genetically Modified Organisms in Food.

PubMed

Eugster, Albert; Murmann, Petra; Kaenzig, Andre; Breitenmoser, Alda

2014-10-01

In routine analysis screening methods based on real-time PCR (polymerase chain reaction) are most commonly used for the detection of genetically modified (GM) plant material in food and feed. Screening tests are based on sequences frequently used for GM development, allowing the detection of a large number of GMOs (genetically modified organisms). Here, we describe the development and validation of a tetraplex real-time PCR screening assay comprising detection systems for the regulatory genes Cauliflower Mosaic Virus 35S promoter, Agrobacterium tumefaciens nos terminator, Cauliflower Mosaic Virus 35S terminator and Figwort Mosaic Virus 34S promoter. Three of the four primer and probe combinations have already been published elsewhere, whereas primers and probe for the 35S terminator have been developed in-house. Adjustment of primer and probe concentrations revealed a high PCR sensitivity with insignificant physical cross-talk between the four detection channels. The sensitivity of each PCR-system is sufficient to detect a GMO concentration as low as 0.05% of the containing respective element. The specificity of the described tetraplex is high when tested on DNA from GM maize, soy, rapeseed and tomato. We also demonstrate the robustness of the system by inter-laboratory tests. In conclusion, this method provides a sensitive and reliable screening procedure for the detection of the most frequently used regulatory elements present in GM crops either authorised or unauthorised for food.

Colorectal cancer screening for average-risk adults: 2018 guideline update from the American Cancer Society.

PubMed

Wolf, Andrew M D; Fontham, Elizabeth T H; Church, Timothy R; Flowers, Christopher R; Guerra, Carmen E; LaMonte, Samuel J; Etzioni, Ruth; McKenna, Matthew T; Oeffinger, Kevin C; Shih, Ya-Chen Tina; Walter, Louise C; Andrews, Kimberly S; Brawley, Otis W; Brooks, Durado; Fedewa, Stacey A; Manassaram-Baptiste, Deana; Siegel, Rebecca L; Wender, Richard C; Smith, Robert A

2018-05-30

In the United States, colorectal cancer (CRC) is the fourth most common cancer diagnosed among adults and the second leading cause of death from cancer. For this guideline update, the American Cancer Society (ACS) used an existing systematic evidence review of the CRC screening literature and microsimulation modeling analyses, including a new evaluation of the age to begin screening by race and sex and additional modeling that incorporates changes in US CRC incidence. Screening with any one of multiple options is associated with a significant reduction in CRC incidence through the detection and removal of adenomatous polyps and other precancerous lesions and with a reduction in mortality through incidence reduction and early detection of CRC. Results from modeling analyses identified efficient and model-recommendable strategies that started screening at age 45 years. The ACS Guideline Development Group applied the Grades of Recommendations, Assessment, Development, and Evaluation (GRADE) criteria in developing and rating the recommendations. The ACS recommends that adults aged 45 years and older with an average risk of CRC undergo regular screening with either a high-sensitivity stool-based test or a structural (visual) examination, depending on patient preference and test availability. As a part of the screening process, all positive results on noncolonoscopy screening tests should be followed up with timely colonoscopy. The recommendation to begin screening at age 45 years is a qualified recommendation. The recommendation for regular screening in adults aged 50 years and older is a strong recommendation. The ACS recommends (qualified recommendations) that: 1) average-risk adults in good health with a life expectancy of more than 10 years continue CRC screening through the age of 75 years; 2) clinicians individualize CRC screening decisions for individuals aged 76 through 85 years based on patient preferences, life expectancy, health status, and prior screening history; and 3) clinicians discourage individuals older than 85 years from continuing CRC screening. The options for CRC screening are: fecal immunochemical test annually; high-sensitivity, guaiac-based fecal occult blood test annually; multitarget stool DNA test every 3 years; colonoscopy every 10 years; computed tomography colonography every 5 years; and flexible sigmoidoscopy every 5 years. CA Cancer J Clin 2018;000:000-000. © 2018 American Cancer Society. © 2018 American Cancer Society.

Breast cancers missed by screening radiologists can be detected by reading mammograms at a distance.

PubMed

Schreutelkamp, Ineke L; Kwee, Robert M; Veekmans, Peter; Adriaensen, Miraude E A P M

2018-05-03

During locally organized quality assurance evaluation sessions for screening radiologists, we noticed that individual screening radiologists did miss tumours which in our opinion could be detected at a distance. To determine whether tumours missed by individual screening radiologists can be detected at a distance. Twenty-eight screening mammograms of 28 females (mean age 63 years, range 49-73) with a pathologically proven malignant tumour missed by individual screening radiologists were mixed with 56 normal screening mammograms of 56 females (mean age 63 years, range 53-74). This test set was independently assessed by a senior screening radiologist and by a radiology resident without prior training in screening mammography at 1.5 m distance from the screen display. Readers were unaware of the prevalence of pathologically proven malignant tumours in the test set. Primary outcome was whether the reader would recall the woman. The senior screening radiologist recalled 28 of 28 women with a pathologically proven malignant tumour (sensitivity of 100%) and 16 of 56 women without pathology (specificity of 71%). The radiology resident recalled 25 of 28 women with a pathologically proven malignant tumour (sensitivity of 89%) and 10 of 56 women without pathology (specificity of 82%). Some malignant tumours missed by an individual screening radiologist can be detected from 1.5 m distance. Therefore, we recommend that screening radiologists consciously take a distant view before closely evaluating the mammogram in detail.

'Nano-immuno test' for the detection of live Mycobacterium avium subspecies paratuberculosis bacilli in the milk samples using magnetic nano-particles and chromogen.

PubMed

Singh, Manju; Singh, Shoor Vir; Gupta, Saurabh; Chaubey, Kundan Kumar; Stephan, Bjorn John; Sohal, Jagdip Singh; Dutta, Manali

2018-04-26

Early rapid detection of Mycobacterium avium subspecies paratuberculosis (MAP) bacilli in milk samples is the major challenge since traditional culture method is time consuming and laboratory dependent. We report a simple, sensitive and specific nano-technology based 'Nano-immuno test' capable of detecting viable MAP bacilli in the milk samples within 10 h. Viable MAP bacilli were captured by MAP specific antibody-conjugated magnetic nano-particles using resazurin dye as chromogen. Test was optimized using true culture positive (10-bovine and 12-goats) and true culture negative (16-bovine and 25-goats) raw milk samples. Domestic livestock species in India are endemically infected with MAP. After successful optimization, sensitivity and specificity of the 'nano-immuno test' in goats with respect to milk culture was 91.7% and 96.0%, respectively. Whereas, it was 90.0% (sensitivity) and 92.6% (specificity) with respect to IS900 PCR. In bovine milk samples, sensitivity and specificity of 'nano-immuno test' with respect to milk culture was 90.0% and 93.7%, respectively. However, with respect to IS900 PCR, the sensitivity and specificity was 88.9% and 94.1%, respectively. Test was validated with field raw milk samples (goats-258 and bovine-138) collected from domestic livestock species to detect live/viable MAP bacilli. Of 138 bovine raw milk samples screened by six diagnostic tests, 81 (58.7%) milk samples were positive for MAP infection in one or more than one diagnostic tests. Of 81 (58.7%) positive bovine raw milk samples, only 24 (17.4%) samples were detected positive for the presence of viable MAP bacilli. Of 258 goats raw milk samples screened by six diagnostic tests, 141 (54.6%) were positive for MAP infection in one or more than one test. Of 141 (54.6%) positive raw milk samples from goats, only 48 (34.0%) were detected positive for live MAP bacilli. Simplicity and efficiency of this novel 'nano-immuno test' makes it suitable for wide-scale screening of milk samples in the field. Standardization, validation and re-usability of functionalized nano-particles and the test was successfully achieved in field samples. Test was highly specific, simple to perform and easy to read by naked eyes and does not require laboratory support in the performance of test. Test has potential to be used as screening test to estimate bio-load of MAP in milk samples at National level.

Screening HIV-Infected Patients with Low CD4 Counts for Cryptococcal Antigenemia prior to Initiation of Antiretroviral Therapy: Cost Effectiveness of Alternative Screening Strategies in South Africa.

PubMed

Larson, Bruce A; Rockers, Peter C; Bonawitz, Rachael; Sriruttan, Charlotte; Glencross, Deborah K; Cassim, Naseem; Coetzee, Lindi M; Greene, Gregory S; Chiller, Tom M; Vallabhaneni, Snigdha; Long, Lawrence; van Rensburg, Craig; Govender, Nelesh P

2016-01-01

In 2015 South Africa established a national cryptococcal antigenemia (CrAg) screening policy targeted at HIV-infected patients with CD4+ T-lymphocyte (CD4) counts <100 cells/ μl who are not yet on antiretroviral treatment (ART). Two screening strategies are included in national guidelines: reflex screening, where a CrAg test is performed on remnant blood samples from CD4 testing; and provider-initiated screening, where providers order a CrAg test after a patient returns for CD4 test results. The objective of this study was to compare costs and effectiveness of these two screening strategies. We developed a decision analytic model to compare reflex and provider-initiated screening in terms of programmatic and health outcomes (number screened, number identified for preemptive treatment, lives saved, and discounted years of life saved) and screening and treatment costs (2015 USD). We estimated a base case with prevalence and other parameters based on data collected during CrAg screening pilot projects integrated into routine HIV care in Gauteng, Free State, and Western Cape Provinces. We conducted sensitivity analyses to explore how results change with underlying parameter assumptions. In the base case, for each 100,000 CD4 tests, the reflex strategy compared to the provider-initiated strategy has higher screening costs ($37,536 higher) but lower treatment costs ($55,165 lower), so overall costs of screening and treatment are $17,629 less with the reflex strategy. The reflex strategy saves more lives (30 lives, 647 additional years of life saved). Sensitivity analyses suggest that reflex screening dominates provider-initiated screening (lower total costs and more lives saved) or saves additional lives for small additional costs (< $125 per life year) across a wide range of conditions (CrAg prevalence, patient and provider behavior, patient survival without treatment, and effectiveness of preemptive fluconazole treatment). In countries with substantial numbers of people with untreated, advanced HIV disease such as South Africa, CrAg screening before initiation of ART has the potential to reduce cryptococcal meningitis and save lives. Reflex screening compared to provider-initiated screening saves more lives and is likely to be cost saving or have low additional costs per additional year of life saved.

Screening HIV-Infected Patients with Low CD4 Counts for Cryptococcal Antigenemia prior to Initiation of Antiretroviral Therapy: Cost Effectiveness of Alternative Screening Strategies in South Africa

PubMed Central

Rockers, Peter C.; Bonawitz, Rachael; Sriruttan, Charlotte; Glencross, Deborah K.; Cassim, Naseem; Coetzee, Lindi M.; Greene, Gregory S.; Chiller, Tom M.; Vallabhaneni, Snigdha; Long, Lawrence; van Rensburg, Craig; Govender, Nelesh P.

2016-01-01

Background In 2015 South Africa established a national cryptococcal antigenemia (CrAg) screening policy targeted at HIV-infected patients with CD4+ T-lymphocyte (CD4) counts <100 cells/ μl who are not yet on antiretroviral treatment (ART). Two screening strategies are included in national guidelines: reflex screening, where a CrAg test is performed on remnant blood samples from CD4 testing; and provider-initiated screening, where providers order a CrAg test after a patient returns for CD4 test results. The objective of this study was to compare costs and effectiveness of these two screening strategies. Methods We developed a decision analytic model to compare reflex and provider-initiated screening in terms of programmatic and health outcomes (number screened, number identified for preemptive treatment, lives saved, and discounted years of life saved) and screening and treatment costs (2015 USD). We estimated a base case with prevalence and other parameters based on data collected during CrAg screening pilot projects integrated into routine HIV care in Gauteng, Free State, and Western Cape Provinces. We conducted sensitivity analyses to explore how results change with underlying parameter assumptions. Results In the base case, for each 100,000 CD4 tests, the reflex strategy compared to the provider-initiated strategy has higher screening costs ($37,536 higher) but lower treatment costs ($55,165 lower), so overall costs of screening and treatment are $17,629 less with the reflex strategy. The reflex strategy saves more lives (30 lives, 647 additional years of life saved). Sensitivity analyses suggest that reflex screening dominates provider-initiated screening (lower total costs and more lives saved) or saves additional lives for small additional costs (< $125 per life year) across a wide range of conditions (CrAg prevalence, patient and provider behavior, patient survival without treatment, and effectiveness of preemptive fluconazole treatment). Conclusions In countries with substantial numbers of people with untreated, advanced HIV disease such as South Africa, CrAg screening before initiation of ART has the potential to reduce cryptococcal meningitis and save lives. Reflex screening compared to provider-initiated screening saves more lives and is likely to be cost saving or have low additional costs per additional year of life saved. PMID:27390864

Evaluation of a Culturally Tailored Education to Promote Breast and Cervical Cancer Screening Among Chinese-Australian Women.

PubMed

Kwok, Cannas; Lim, Danforn

2016-09-01

This paper aims to evaluate the impact of the culturally sensitive and linguistically appropriate education program on the following: (i) awareness of screening practices (breast awareness, mammogram, and Pap smear test); (ii) screening intention within the next six months; and (iii) knowledge about breast and cervical cancer among Chinese-Australian women. Titled "Happy and Healthy Life in Sydney," this was a quasi-experimental study with both pre- and post-test design. A convenience sample of 288 Chinese women was recruited through Chinese organizations such as churches and community centers. Participants completed the questionnaires before and after the educational program. The results show that the program was effective in promoting awareness of breast and cervical cancer screening and resulted in increased participative intentions in both mammogram and Pap smear testing within the next 6 months. Results also indicate that knowledge and belief scores were significantly increased. Our study supports that educational programs which use culturally sensitive and linguistically appropriate strategies are effective in improving both knowledge of breast and cervical cancer and awareness of their early detection practices among Chinese-Australian women.

Intracellular human papillomavirus E6, E7 mRNA quantification predicts CIN 2+ in cervical biopsies better than Papanicolaou screening for women regardless of age.

PubMed

Pierry, Deirdre; Weiss, Gerald; Lack, Benjamin; Chen, Victor; Fusco, Judy

2012-08-01

Cervical cancer screening in women younger than 30 years relies on cervical cytology because of the poor performance of human papillomavirus (HPV) DNA testing in this age group. To determine the performance of in-cell HPV E6, E7 mRNA quantification (HPV OncoTect) for the detection of high-grade cervical intraepithelial neoplasia in women younger than 30 years. We analyzed 3133 cytology specimens from a screening population of women aged 19-75 years investigate HPV OncoTect as a triage/secondary screening test for atypical squamous cells of undetermined significance (ASCUS) and low-grade squamous intraepithelial lesion (LSIL) cytology in women younger than 30 years. Test results were compared to histology in 246 cases. The sensitivity of E6, E7 mRNA was 89% for CIN 2+ and 100% for CIN 3+ lesions in women 30 years and older. In women younger than 30 years, the sensitivity of E6, E7 mRNA for CIN 2+ lesions was 88% for CIN 2+ and 92% for CIN 3+ lesions. Abnormal cytology (≥ASCUS) exhibited a sensitivity of 89% for CIN 2+ and 100% for CIN 3+ in women 30 years and older and 96% sensitivity for CIN 2+ and 93% sensitivity for CIN 3+ in women younger than 30. The specificity of E6, E7 mRNA was >80% for CIN 2+ and CIN 3+ in both groups of women compared to a specificity of abnormal cytology of <10% for CIN 2+ and CIN 3+ in both groups. HPV OncoTect demonstrates a performance that would be effective for ASCUS/LSIL triage in women including those younger than 30 years.

Development and validation of a highly sensitive urine-based test to identify patients with colonic adenomatous polyps.

PubMed

Wang, Haili; Tso, Victor; Wong, Clarence; Sadowski, Dan; Fedorak, Richard N

2014-03-20

Adenomatous polyps are precursors of colorectal cancer; their detection and removal is the goal of colon cancer screening programs. However, fecal-based methods identify patients with adenomatous polyps with low levels of sensitivity. The aim or this study was to develop a highly accurate, prototypic, proof-of-concept, spot urine-based diagnostic test using metabolomic technology to distinguish persons with adenomatous polyps from those without polyps. Prospective urine and stool samples were collected from 876 participants undergoing colonoscopy examination in a colon cancer screening program, from April 2008 to October 2009 at the University of Alberta. Colonoscopy reference standard identified 633 participants with no colonic polyps and 243 with colonic adenomatous polyps. One-dimensional nuclear magnetic resonance spectra of urine metabolites were analyzed to define a diagnostic metabolomic profile for colonic adenomas. A urine metabolomic diagnostic test for colonic adenomatous polyps was established using 67% of the samples (un-blinded training set) and validated using the other 33% of the samples (blinded testing set). The urine metabolomic diagnostic test's specificity and sensitivity were compared with those of fecal-based tests. Using a two-component, orthogonal, partial least-squares model of the metabolomic profile, the un-blinded training set identified patients with colonic adenomatous polyps with 88.9% sensitivity and 50.2% specificity. Validation using the blinded testing set confirmed sensitivity and specificity values of 82.7% and 51.2%, respectively. Sensitivities of fecal-based tests to identify colonic adenomas ranged from 2.5 to 11.9%. We describe a proof-of-concept spot urine-based metabolomic diagnostic test that identifies patients with colonic adenomatous polyps with a greater level of sensitivity (83%) than fecal-based tests.

Time and travel costs incurred by women attending antenatal tests: A costing study.

PubMed

Verhoef, Talitha I; Daley, Rebecca; Vallejo-Torres, Laura; Chitty, Lyn S; Morris, Stephen

2016-09-01

to estimate the costs to women, their friends and family for different antenatal tests in the Down's syndrome (DS) screening pathway. questionnaire-based costing study. eight maternity clinics across the UK. pregnant women (n=574) attending an appointment for DS screening, NIPT or invasive testing between December 2013 and September 2014. using data collected from the questionnaires we calculated the total costs to women by multiplying the time spent at the hospital and travelling to and from it by the opportunity costs of the women and accompanying person and adding travel and childcare costs. Assumptions about the value of opportunity costs were tested in one-way sensitivity analyses. The main outcome measure was the mean cost to the women and friends/family for each test (DS screening, NIPT, and invasive testing). mean costs to women and their family/friend were £33.96 per visit, of which £22.47 were time costs, £9.15 were travel costs and £2.34 were childcare costs. Costs were lowest for NIPT (£22), £32 for DS screening (£44 if combined with NIPT), and highest for invasive testing (£60). Sensitivity analysis revealed that variations around the value of leisure time opportunity costs had the largest influence on the results. there are considerable costs to women, their friends and family when attending different tests in the DS screening pathway. when assessing the cost-effectiveness of changes to this pathway, costs to women should be considered. Copyright © 2016 Elsevier Ltd. All rights reserved.

Screening tests for aphasia in patients with stroke: a systematic review.

PubMed

El Hachioui, Hanane; Visch-Brink, Evy G; de Lau, Lonneke M L; van de Sandt-Koenderman, Mieke W M E; Nouwens, Femke; Koudstaal, Peter J; Dippel, Diederik W J

2017-02-01

Aphasia has a large impact on the quality of life and adds significantly to the costs of stroke care. Early recognition of aphasia in stroke patients is important for prognostication and well-timed treatment planning. We aimed to identify available screening tests for differentiating between aphasic and non-aphasic stroke patients, and to evaluate test accuracy, reliability, and feasibility. We searched PubMed, EMbase, Web of Science, and PsycINFO for published studies on screening tests aimed at assessing aphasia in stroke patients. The reference lists of the selected articles were scanned, and several experts were contacted to detect additional references. Of each screening test, we estimated the sensitivity, specificity, likelihood ratio of a positive test, likelihood ratio of a negative test, and diagnostic odds ratio (DOR), and rated the degree of bias of the validation method. We included ten studies evaluating eight screening tests. There was a large variation across studies regarding sample size, patient characteristics, and reference tests used for validation. Many papers failed to report on the consecutiveness of patient inclusion, time between aphasia onset and administration of the screening test, and blinding. Of the three studies that were rated as having an intermediate or low risk of bias, the DOR was highest for the Language Screening Test and ScreeLing. Several screening tools for aphasia in stroke are available, but many tests have not been verified properly. Methodologically sound validation studies of aphasia screening tests are needed to determine their usefulness in clinical practice.

Cervical screening in HPV-vaccinated populations.

PubMed

Canfell, K

2018-06-01

Cervical screening with cytology has been the basis for substantial reductions in cervical cancer incidence and mortality in most high-income countries over the last few decades. More recently, there have been two key, parallel developments which have prompted a major re-consideration of cervical screening. The first is the emergence of evidence on the improved sensitivity of human papillomavirus (HPV) DNA testing compared to cytology, and the second is the large-scale deployment of prophylactic vaccination against HPV. A key challenge to be overcome before HPV screening could be introduced into national cervical screening programs was the specificity of an infection, for detection of precancerous lesions. This has been done in three ways: (1) by considering the appropriate age for starting HPV screening (30 years in unvaccinated populations and 25 years in populations with mature vaccination programs and high vaccine uptake) and the appropriate screening interval; (2) via development of clinical HPV tests, which are (by design) not as sensitive to low viral loads; and (3) by introducing effective triaging for HPV-positive women, which further risk-stratifies women before referral for diagnostic evaluation. This review discusses these major developments and describes how the benefits of HPV screening are being optimized in both unvaccinated and vaccinated populations.

Rapid Point-Of-Care Breath Test for Biomarkers of Breast Cancer and Abnormal Mammograms

PubMed Central

Phillips, Michael; Beatty, J. David; Cataneo, Renee N.; Huston, Jan; Kaplan, Peter D.; Lalisang, Roy I.; Lambin, Philippe; Lobbes, Marc B. I.; Mundada, Mayur; Pappas, Nadine; Patel, Urvish

2014-01-01

Background Previous studies have reported volatile organic compounds (VOCs) in breath as biomarkers of breast cancer and abnormal mammograms, apparently resulting from increased oxidative stress and cytochrome p450 induction. We evaluated a six-minute point-of-care breath test for VOC biomarkers in women screened for breast cancer at centers in the USA and the Netherlands. Methods 244 women had a screening mammogram (93/37 normal/abnormal) or a breast biopsy (cancer/no cancer 35/79). A mobile point-of-care system collected and concentrated breath and air VOCs for analysis with gas chromatography and surface acoustic wave detection. Chromatograms were segmented into a time series of alveolar gradients (breath minus room air). Segmental alveolar gradients were ranked as candidate biomarkers by C-statistic value (area under curve [AUC] of receiver operating characteristic [ROC] curve). Multivariate predictive algorithms were constructed employing significant biomarkers identified with multiple Monte Carlo simulations and cross validated with a leave-one-out (LOO) procedure. Results Performance of breath biomarker algorithms was determined in three groups: breast cancer on biopsy versus normal screening mammograms (81.8% sensitivity, 70.0% specificity, accuracy 79% (73% on LOO) [C-statistic value], negative predictive value 99.9%); normal versus abnormal screening mammograms (86.5% sensitivity, 66.7% specificity, accuracy 83%, 62% on LOO); and cancer versus no cancer on breast biopsy (75.8% sensitivity, 74.0% specificity, accuracy 78%, 67% on LOO). Conclusions A pilot study of a six-minute point-of-care breath test for volatile biomarkers accurately identified women with breast cancer and with abnormal mammograms. Breath testing could potentially reduce the number of needless mammograms without loss of diagnostic sensitivity. PMID:24599224

Comparative effectiveness of combined digital mammography and tomosynthesis screening for women with dense breasts.

PubMed

Lee, Christoph I; Cevik, Mucahit; Alagoz, Oguzhan; Sprague, Brian L; Tosteson, Anna N A; Miglioretti, Diana L; Kerlikowske, Karla; Stout, Natasha K; Jarvik, Jeffrey G; Ramsey, Scott D; Lehman, Constance D

2015-03-01

To evaluate the effectiveness of combined biennial digital mammography and tomosynthesis screening, compared with biennial digital mammography screening alone, among women with dense breasts. An established, discrete-event breast cancer simulation model was used to estimate the comparative clinical effectiveness and cost-effectiveness of biennial screening with both digital mammography and tomosynthesis versus digital mammography alone among U.S. women aged 50-74 years with dense breasts from a federal payer perspective and a lifetime horizon. Input values were estimated for test performance, costs, and health state utilities from the National Cancer Institute Breast Cancer Surveillance Consortium, Medicare reimbursement rates, and medical literature. Sensitivity analyses were performed to determine the implications of varying key model parameters, including combined screening sensitivity and specificity, transient utility decrement of diagnostic work-up, and additional cost of tomosynthesis. For the base-case analysis, the incremental cost per quality-adjusted life year gained by adding tomosynthesis to digital mammography screening was $53 893. An additional 0.5 deaths were averted and 405 false-positive findings avoided per 1000 women after 12 rounds of screening. Combined screening remained cost-effective (less than $100 000 per quality-adjusted life year gained) over a wide range of incremental improvements in test performance. Overall, cost-effectiveness was most sensitive to the additional cost of tomosynthesis. Biennial combined digital mammography and tomosynthesis screening for U.S. women aged 50-74 years with dense breasts is likely to be cost-effective if priced appropriately (up to $226 for combined examinations vs $139 for digital mammography alone) and if reported interpretive performance metrics of improved specificity with tomosynthesis are met in routine practice.

Sensitivity and Specificity of a Five-Minute Cognitive Screening Test in Patients With Heart Failure.

PubMed

Cameron, Janette D; Gallagher, Robyn; Pressler, Susan J; McLennan, Skye N; Ski, Chantal F; Tofler, Geoffrey; Thompson, David R

2016-02-01

Cognitive impairment occurs in up to 80% of patients with heart failure (HF). The National Institute for Neurological Disorders and Stroke (NINDS) and the Canadian Stroke Network (CSN) recommend a 5-minute cognitive screening protocol that has yet to be psychometrically evaluated in HF populations. The aim of this study was to conduct a secondary analysis of the sensitivity and specificity of the NINDS-CSN brief cognitive screening protocol in HF patients. The Montreal Cognitive Assessment (MoCA) was administered to 221 HF patients. The NINDS-CSN screen comprises 3 MoCA items, with lower scores indicating poorer cognitive function. Receiver operator characteristic (ROC) curves were constructed, determining the sensitivity, specificity and appropriate cutoff scores of the NINDS-CSN screen. In an HF population aged 76 ± 12 years, 136 (62%) were characterized with cognitive impairment (MoCA <26). Scores on the NINDS-CSN screen ranged from 3-11. The area under the receiver operating characteristic curve indicated good accuracy in screening for cognitive impairment (0.88; P < .01; 95% CI 0.83-0.92). A cutoff score of ≤9 provided 89% sensitivity and 71% specificity. The NINDS-CSN protocol offers clinicians a feasible telephone method to screen for cognitive impairment in patients with HF. Future studies should include a neuropsychologic battery to more comprehensively examine the diagnostic accuracy of brief cognitive screening protocols. Copyright © 2016 Elsevier Inc. All rights reserved.

Proceedings of the drug testing laboratory managers symposium, 28 January--1 February 1974. Final report

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

Noe, E.R.; Romanchick, W.A.; Ainsworth, C.A. III

1975-06-01

This report deals with broad concepts of managing mass screening programs for drugs of abuse; e.g., morphine, barbiturate, amphetamine, cocaine, and methaqualone. The interactions of the screening process and of the rehabilitation program were covered. Psychotherapy and group therapy are both utilized in rehabilitation programs. The semiautomated radioimmunoassay (RIA) screening procedures are both sensitive and specific at nanogram quantities. Future evaluations of a wafer disk transferral system and of a latex test for morphine are presented. The unique quality control system employed by military drug abuse testing laboratories is discussed. (Author) (GRA)

Screening for Trichomonas vaginalis in a Large High-Risk Population: Prevalence Among Men and Women Determined by Nucleic Acid Amplification Testing.

PubMed

Schwebke, Jane; Merriweather, Anthony; Massingale, Sharon; Scisney, Mary; Hill, Craig; Getman, Damon

2018-05-01

Men and women attending family planning and sexually transmitted disease clinics for sexually transmitted infection screening in 2012 to 2013 were tested for Trichomonas vaginalis (TV) using a sensitive nucleic acid amplification test. T. vaginalis prevalence in urogenital samples was 11.3% in 77,740 women and 6.1% in 12,604 men, and increased with age in both sexes.

Serologic Screening for Genital Herpes: An Updated Evidence Report and Systematic Review for the US Preventive Services Task Force.

PubMed

Feltner, Cynthia; Grodensky, Catherine; Ebel, Charles; Middleton, Jennifer C; Harris, Russell P; Ashok, Mahima; Jonas, Daniel E

2016-12-20

Genital herpes simplex virus (HSV) infection is a prevalent sexually transmitted infection. Vertical transmission of HSV can lead to fetal morbidity and mortality. To assess the evidence on serologic screening and preventive interventions for genital HSV infection in asymptomatic adults and adolescents to support the US Preventive Services Task Force for an updated recommendation statement. MEDLINE, Cochrane Library, EMBASE, and trial registries through March 31, 2016. Surveillance for new evidence in targeted publications was conducted through October 31, 2016. English-language randomized clinical trials (RCTs) comparing screening with no screening in persons without past or current symptoms of genital herpes; studies evaluating accuracy and harms of serologic screening tests for HSV-2; RCTs assessing preventive interventions in asymptomatic persons seropositive for HSV-2. Dual review of abstracts, full-text articles, and study quality; pooled sensitivities and specificities of screening tests using a hierarchical summary receiver operating characteristic curve analysis when at least 3 similar studies were available. Accuracy of screening tests, benefits of screening, harms of screening, reduction in genital herpes outbreaks. A total of 17 studies (n = 9736 participants; range, 24-3290) in 19 publications were included. No RCTs compared screening with no screening. Most studies of the accuracy of screening tests were from populations with high HSV-2 prevalence (greater than 40% based on Western blot). Pooled estimates of sensitivity and specificity of the most commonly used test at the manufacturer's cutpoint were 99% (95% CI, 97%-100%) and 81% (95% CI, 68%-90%), respectively (10 studies; n = 6537). At higher cutpoints, pooled estimates were 95% (95% CI, 91%-97%) and 89% (95% CI, 82%-93%), respectively (7 studies; n = 5516). Use of this test at the manufacturer's cutpoint in a population of 100 000 with a prevalence of HSV-2 of 16% (the seroprevalence in US adults with unknown symptom status) would result in 15 840 true-positive results and 15 960 false-positive results (positive predictive value, 50%). Serologic screening for genital herpes was associated with psychosocial harms, including distress and anxiety related to positive test results. Four RCTs compared preventive medications with placebo, 2 in nonpregnant asymptomatic adults who were HSV-2 seropositive and 2 in HSV-2-serodiscordant couples. Results in both populations were heterogeneous and inconsistent. Serologic screening for genital herpes is associated with a high rate of false-positive test results and potential psychosocial harms. Evidence from RCTs does not establish whether preventive antiviral medication for asymptomatic HSV-2 infection has benefit.

Screening strategies for atrial fibrillation: a systematic review and cost-effectiveness analysis.

PubMed

Welton, Nicky J; McAleenan, Alexandra; Thom, Howard Hz; Davies, Philippa; Hollingworth, Will; Higgins, Julian Pt; Okoli, George; Sterne, Jonathan Ac; Feder, Gene; Eaton, Diane; Hingorani, Aroon; Fawsitt, Christopher; Lobban, Trudie; Bryden, Peter; Richards, Alison; Sofat, Reecha

2017-05-01

Atrial fibrillation (AF) is a common cardiac arrhythmia that increases the risk of thromboembolic events. Anticoagulation therapy to prevent AF-related stroke has been shown to be cost-effective. A national screening programme for AF may prevent AF-related events, but would involve a substantial investment of NHS resources. To conduct a systematic review of the diagnostic test accuracy (DTA) of screening tests for AF, update a systematic review of comparative studies evaluating screening strategies for AF, develop an economic model to compare the cost-effectiveness of different screening strategies and review observational studies of AF screening to provide inputs to the model. Systematic review, meta-analysis and cost-effectiveness analysis. Primary care. Adults. Screening strategies, defined by screening test, age at initial and final screens, screening interval and format of screening {systematic opportunistic screening [individuals offered screening if they consult with their general practitioner (GP)] or systematic population screening (when all eligible individuals are invited to screening)}. Sensitivity, specificity and diagnostic odds ratios; the odds ratio of detecting new AF cases compared with no screening; and the mean incremental net benefit compared with no screening. Two reviewers screened the search results, extracted data and assessed the risk of bias. A DTA meta-analysis was perfomed, and a decision tree and Markov model was used to evaluate the cost-effectiveness of the screening strategies. Diagnostic test accuracy depended on the screening test and how it was interpreted. In general, the screening tests identified in our review had high sensitivity (> 0.9). Systematic population and systematic opportunistic screening strategies were found to be similarly effective, with an estimated 170 individuals needed to be screened to detect one additional AF case compared with no screening. Systematic opportunistic screening was more likely to be cost-effective than systematic population screening, as long as the uptake of opportunistic screening observed in randomised controlled trials translates to practice. Modified blood pressure monitors, photoplethysmography or nurse pulse palpation were more likely to be cost-effective than other screening tests. A screening strategy with an initial screening age of 65 years and repeated screens every 5 years until age 80 years was likely to be cost-effective, provided that compliance with treatment does not decline with increasing age. A national screening programme for AF is likely to represent a cost-effective use of resources. Systematic opportunistic screening is more likely to be cost-effective than systematic population screening. Nurse pulse palpation or modified blood pressure monitors would be appropriate screening tests, with confirmation by diagnostic 12-lead electrocardiography interpreted by a trained GP, with referral to a specialist in the case of an unclear diagnosis. Implementation strategies to operationalise uptake of systematic opportunistic screening in primary care should accompany any screening recommendations. Many inputs for the economic model relied on a single trial [the Screening for Atrial Fibrillation in the Elderly (SAFE) study] and DTA results were based on a few studies at high risk of bias/of low applicability. Comparative studies measuring long-term outcomes of screening strategies and DTA studies for new, emerging technologies and to replicate the results for photoplethysmography and GP interpretation of 12-lead electrocardiography in a screening population. This study is registered as PROSPERO CRD42014013739. The National Institute for Health Research Health Technology Assessment programme.

The Faces Symbol Test, a newly developed screening instrument to assess cognitive decline related to multiple sclerosis: first results of the Berlin Multi-Centre FST Validation Study.

PubMed

Scherer, P; Penner, I K; Rohr, A; Boldt, H; Ringel, I; Wilke-Burger, H; Burger-Deinerth, E; Isakowitsch, K; Zimmermann, M; Zahrnt, S; Hauser, R; Hilbert, K; Tiel-Wilck, K; Anvari, K; Behringer, A; Peglau, I; Friedrich, H; Plenio, A; Benesch, G; Ehret, R; Nippert, I; Finke, G; Schulz, I; Bergtholdt, B; Breitkopf, S; Kaskel, P; Reischies, F; Kugler, J

2007-04-01

Reliable, language-independent, short screening instruments to test for cognitive function in patients with multiple sclerosis (MS) remain rare, despite the high number of patients affected by cognitive decline. We developed a new, short screening instrument, the Faces Symbol Test (FST), and compared its diagnostic test characteristics with a composite of the Digit Symbol Substitution Test (DSST) and the Paced Auditory Serial Addition Test (PASAT), in 108 MS patients and 33 healthy controls. An Informant-Report Questionnaire, a Self-Report Questionnaire, and a neurologist's estimation of the Every Day Life Cognitive Status were also applied to the MS patients. The statistical analyses comprised of a receiver operating characteristic analysis for test accuracy and for confounding variables. The PASAT and DSST composite score estimated that 36.5% of the MS patients had cognitive impairment. The FST estimated that 40.7% of the MS patients were cognitively impaired (sensitivity 84%; specificity 85%). The FST, DSST and PASAT results were significantly correlated with the patients' physical impairment, as measured by the Expanded Disability Status Scale (EDSS). The results suggest that the FST might be a culture-free, sensitive, and practical short screening instrument for the detection of cognitive decline in patients with MS, including those in the early stages.

Cognitive Screening in Brain Tumors: Short but Sensitive Enough?

PubMed Central

Robinson, Gail A.; Biggs, Vivien; Walker, David G.

2015-01-01

Cognitive deficits in brain tumors are generally thought to be relatively mild and non-specific, although recent evidence challenges this notion. One possibility is that cognitive screening tools are being used to assess cognitive functions but their sensitivity to detect cognitive impairment may be limited. For improved sensitivity to recognize mild and/or focal cognitive deficits in brain tumors, neuropsychological evaluation tailored to detect specific impairments has been thought crucial. This study investigates the sensitivity of a cognitive screening tool, the Montreal Cognitive Assessment (MoCA), compared to a brief but tailored cognitive assessment (CA) for identifying cognitive deficits in an unselected primary brain tumor sample (i.e., low/high-grade gliomas, meningiomas). Performance is compared on broad measures of impairment: (a) number of patients impaired on the global screening measure or in any cognitive domain; and (b) number of cognitive domains impaired and specific analyses of MoCA-Intact and MoCA-Impaired patients on specific cognitive tests. The MoCA-Impaired group obtained lower naming and word fluency scores than the MoCA-Intact group, but otherwise performed comparably on cognitive tests. Overall, based on our results from patients with brain tumor, the MoCA has extremely poor sensitivity for detecting cognitive impairments and a brief but tailored CA is necessary. These findings will be discussed in relation to broader issues for clinical management and planning, as well as specific considerations for neuropsychological assessment of brain tumor patients. PMID:25815273

Screening tests for distal symmetrical polyneuropathy in Latin American patients with type 2 diabetes mellitus.

PubMed

Gómez-Banoy, Nicolás; Cuevas, Virginia; Soler, Fernando; Pineda, Maria Fernanda; Mockus, Ismena

2017-01-01

This cross sectional study intended to evaluate two bedside tests (Neuropad and VibraTip) as screening tools for distal symmetrical polyneuropathy (DSPN) in Latin American patients with type 2 diabetes mellitus (T2D). Ninety-three Colombian patients diagnosed with T2D were recruited. Anthropometric variables, glycemic control parameters, lipid profile and renal function were assessed for each patient. DSPN was defined by a Michigan Neuropathy Screening Instrument (MNSI) clinical score greater than 2. Both Neuropad and Vibratip tests were applied to each patient. Contingency analyses were performed to evaluate the diagnostic power of both tools. The prevalence of DSPN determined clinically by MNSI was 25.8%. DSPN in these patients was associated with age, worsening renal function, and insulin treatment. The sensitivity and specificity of the Neuropad test for DSPN was 66.6% and 63% respectively. Its negative predictive value (NPV) was 84.6%. The VibraTip test exhibited a sensitivity of 54.1% and specificity of 91.3%, with a NPV of 85.1%. Neuropad and VibraTip are reliable screening tools for DSPN in Latin American population. VibraTip presents a considerable diagnostic power for DSPN in this population. Further studies regarding the cost-effectiveness of these tools in clinical practice are needed.

Is breast compression associated with breast cancer detection and other early performance measures in a population-based breast cancer screening program?

PubMed

Moshina, Nataliia; Sebuødegård, Sofie; Hofvind, Solveig

2017-06-01

We aimed to investigate early performance measures in a population-based breast cancer screening program stratified by compression force and pressure at the time of mammographic screening examination. Early performance measures included recall rate, rates of screen-detected and interval breast cancers, positive predictive value of recall (PPV), sensitivity, specificity, and histopathologic characteristics of screen-detected and interval breast cancers. Information on 261,641 mammographic examinations from 93,444 subsequently screened women was used for analyses. The study period was 2007-2015. Compression force and pressure were categorized using tertiles as low, medium, or high. χ 2 test, t tests, and test for trend were used to examine differences between early performance measures across categories of compression force and pressure. We applied generalized estimating equations to identify the odds ratios (OR) of screen-detected or interval breast cancer associated with compression force and pressure, adjusting for fibroglandular and/or breast volume and age. The recall rate decreased, while PPV and specificity increased with increasing compression force (p for trend <0.05 for all). The recall rate increased, while rate of screen-detected cancer, PPV, sensitivity, and specificity decreased with increasing compression pressure (p for trend <0.05 for all). High compression pressure was associated with higher odds of interval breast cancer compared with low compression pressure (1.89; 95% CI 1.43-2.48). High compression force and low compression pressure were associated with more favorable early performance measures in the screening program.

High-throughput screening, predictive modeling and computational embryology - Abstract

EPA Science Inventory

High-throughput screening (HTS) studies are providing a rich source of data that can be applied to chemical profiling to address sensitivity and specificity of molecular targets, biological pathways, cellular and developmental processes. EPA’s ToxCast project is testing 960 uniq...

Evaluation of the fluorescent gonococcal test-heated.

PubMed Central

Gaafar, H A

1976-01-01

In a 1-year evaluation of the indirect fluorescent antibody test for gonorrhea, 16,127 specimens from low-and high-risk groups were examined, and the results were compared with culture, history of exposure to a known patient, and clinical signs and symptoms. The results confirmed the usefulness of the indirect fluorescent antibody test for gonorrhea as a screening procedure, especially for women in the low-risk group. The test is more economic and probably more sensitive than culture for mass screening of asymptomatic women. PMID:791965

Use of a single alcohol screening question to identify other drug use.

PubMed

Smith, Peter C; Cheng, Debbie M; Allensworth-Davies, Donald; Winter, Michael R; Saitz, Richard

2014-06-01

People who consume unhealthy amounts of alcohol are more likely to use illicit drugs. We tested the ability of a screening test for unhealthy alcohol use to simultaneously detect drug use. Adult English speaking patients (n=286) were enrolled from a primary care waiting room. They were asked the screening question for unhealthy alcohol use "How many times in the past year have you had X or more drinks in a day?", where X is 5 for men and 4 for women, and a response of one or more is considered positive. A standard diagnostic interview was used to determine current (past year) drug use or a drug use disorder (abuse or dependence). Oral fluid testing was also used to detect recent use of common drugs of abuse. The single screening question for unhealthy alcohol use was 67.6% sensitive (95% confidence interval [CI], 50.2-82.0%) and 64.7% specific (95% CI, 58.4-70.6%) for the detection of a drug use disorder. It was similarly insensitive for drug use detected by oral fluid testing and/or self-report. Although a patient with a drug use disorder has twice the odds of screening positive for unhealthy alcohol use compared to one without a drug use disorder, suggesting patients who screen positive for alcohol should be asked about drug use, a single screening question for unhealthy alcohol use was not sensitive or specific for the detection of other drug use or drug use disorders in a sample of primary care patients. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

ADHD Is Highly Prevalent in Patients Seeking Treatment for Cannabis Use Disorders.

PubMed

Notzon, Daniel P; Pavlicova, Martina; Glass, Andrew; Mariani, John J; Mahony, Amy L; Brooks, Daniel J; Levin, Frances R

2016-03-31

To estimate the prevalence of ADHD and determine an effective screening test for ADHD in a population-seeking treatment for cannabis use disorders. The Conners Adult ADHD Diagnostic Interview forDiagnostic and Statistical Manual of Mental Disorders, Fourth Edition(DSM-IV; CAADID) was used to generate sensitivity and specificity data for ADHD screening tests, which were then administered to 99 participants seeking treatment for cannabis use disorders to estimate ADHD prevalence. The prevalence estimated from the Wender Utah Rating Scale (WURS) was 45% (sensitivity = 0.88, sensitivity of 0.75), from the Conners Adult ADHD Rating Scale (CAARS) 34% (sensitivity = 0.80, specificity = 0.91), from the WURS + CAARS 36% (sensitivity = 0.71, specificity = 0.95), and from the Adult ADHD Self-Report Scale (ASRS) 46% (sensitivity = 0.61, specificity = 0.86). The prevalence of ADHD in adults seeking treatment for cannabis use disorders is estimated to be between 34% and 46%. The WURS paired with the CAARS provides excellent sensitivity and specificity for the diagnosis of ADHD in this population. © The Author(s) 2016.

Application of rat mast cell incubates as a possible short-time test for sensitizing occupational chemicals.

PubMed

Diel, F; Neidhart, B; Oprée, W

1981-01-01

The direct action of sensitizing occupational chemicals (formaldehyde, phenol, phenylhydrazine, p-aminophenol) on rat mast cells was investigated by determination of histamine using HPLC separation and fluorimetric detection. It turned out that dispensed mast cells from immunized and non-immunized Wistar-rats are more sensitive than small-cut lung tissue slices. Passive cutaneous anaphylaxis was negative after a fortnight sensitizing experiment with the here described occupational chemicals. Short-time tests with rat mast cells reflect anaphylactoid response and are suitable for the screening of sensitizing chemicals.

Comparison of three screening tests for autism in preterm children with birth weights less than 1,500 grams

PubMed Central

Dudova, Iva; Markova, Daniela; Kasparova, Martina; Zemankova, Jana; Beranova, Stepanka; Urbanek, Tomas; Hrdlicka, Michal

2014-01-01

Background Preterm children seem to be at increased risk for autism spectrum disorders (ASD). Methods Parents of 157 children with birth weights less than 1,500 g (age 2 years, corrected for prematurity; 88 boys, 69 girls) completed screening questionnaires. The screening battery included the Modified Checklist for Autism in Toddlers (M-CHAT), Communication and Symbolic Behavior Scales Developmental Profile Infant-Toddler Checklist (CSBS-DP-ITC), and the Infant/Toddler Sensory Profile (ITSP). Children with disabilities were excluded. All children who screened positive on any of the screening tools were subsequently assessed by clinical examination including the Autism Diagnostic Observation Schedule. Results Fifty-six children (35.7%) screened positive on at least one of the parental screening questionnaires. Of the 56 children who tested positive, 33 participated in the detailed clinical follow-up assessment. A diagnosis of ASD was confirmed in 13 of the 33 children. The ASD prevalence was 9.7% of the sample. Analysis of children with and without an ASD diagnosis found significant differences relative to gestational age (26.9 weeks vs 28.3 weeks, P=0.033) and length of the stay in hospital (89.5 days vs 75.4 days, P=0.042). The screening tool with the most positive results was CSBS-DP-ITC (42 positive screens [PS]), followed by M-CHAT (28 PS), and ITSP (22 PS). Differences in the frequency of PS among the tests were significant (P=0.008). CSBS-DP-ITC had the highest sensitivity (0.846), followed by M-CHAT (0.692) and ITSP (0.462). Conclusion Our results indicate a higher prevalence of autism in children with birth weights <1,500 g at 2 years of age compared to the general population prevalence. The ASD diagnosis was associated with shorter gestation times and longer hospital stays. Our findings support the simultaneous use of more than one screening tests in order to increase screening sensitivity. PMID:25484588

Use of the Dynamic Visual Acuity Test as a screener for community-dwelling older adults who fall.

PubMed

Honaker, Julie A; Shepard, Neil T

2011-01-01

Adequate function of the peripheral vestibular system, specifically the vestibulo-ocular reflex (VOR; a network of neural connections between the peripheral vestibular system and the extraocular muscles) is essential for maintaining stable vision during head movements. Decreased visual acuity resulting from an impaired peripheral vestibular system may impede balance and postural control and place an individual at risk of falling. Therefore, sensitive measures of the vestibular system are warranted to screen for the tendency to fall, alerting clinicians to recommend further risk of falling assessment and referral to a falling risk reduction program. Dynamic Visual Acuity (DVA) testing is a computerized VOR assessment method to evaluate the peripheral vestibular system during head movements; reduced visual acuity as documented with DVA testing may be sensitive to screen for falling risk. This study examined the sensitivity and specificity of the computerized DVA test with yaw plane head movements for identifying community-dwelling adults (58-78 years) who are prone to falling. A total of 16 older adults with a history of two or more unexplained falls in the previous twelve months and 16 age and gender matched controls without a history of falls in the previous twelve months participated. Computerized DVA with horizontal head movements at a fixed velocity of 120 deg/sec was measured and compared with the Dynamic Gait Index (DGI) a gold standard gait assessment measurement for identifying falling risk. Receiver operating characteristics (ROC) curve analysis and area under the ROC curve (AUC) were used to assess the sensitivity and specificity of the computerized DVA as a screening measure for falling risk as determined by the DGI. Results suggested a link between computerized DVA and the propensity to fall; DVA in the yaw plane was found to be a sensitive (92%) and accurate screening measure when using a cutoff logMAR value of >0.25.

Asymptomatic bacteriuria in pregnant women attending Boo-Ali Hospital Tehran Iran: Urine analysis vs. urine culture.

PubMed

Etminan-Bakhsh, Mina; Tadi, Sima; Darabi, Roksana

2017-11-01

Asymptomatic bacteriuria is one of the common problems in pregnancy. Asymptomatic bacteriuria is associated with pyelonephritis, preterm labor and low birth weight infants. The physiological and anatomical changes in pregnancy facilitate urinary tract infection (UTI) during pregnancy. Several tests are available for diagnosis of asymptomatic bacteriuria. The urine culture is a gold standard diagnostic test for asymptomatic bacteriuria but it is expensive and time-consuming. Screening methods may be useful in detecting high-risk pregnant women for asymptomatic bacteriuria. The aim of the present study was to compare urine analysis as a rapid screening test to urine culture in diagnosis of asymptomatic bacteriuria. A total of 123 pregnant women attending the obstetrics clinic of Boo-Ali hospital in Tehran, Iran from March 2013 to September 2014 were included in the present diagnostic cross-sectional study. One hundred twenty three mid-stream urine samples were inoculated into cultures and were processed by dipstick (nitrite test and leucocyte esterase test) and microscopic pus cell count. The sensitivity, specificity, positive predictive value and negative predictive value of nitrite test, leucocyte esterase test and microscopic pus cell count were compared with urine culture in diagnosis of asymptomatic bacteriuria by using SPSS version 19. Of 123 urine samples, significant asymptomatic bacteriuria (≥10 4 cfu/Ml) was detected in 8 (6.5%) subjects. The sensitivity and specificity of nitrite test were 37% and 100% respectively. The sensitivity of pus cell count alone and leucocyte esterase test alone were 100% but the specificity of them were 64% and 65% respectively. We found high negative predictive value by Pus cell count and the leucocyte esterase test (100%) and low positive predictive value by them (16% and 17% respectively). Urine culture is the most useful test for diagnosis of asymptomatic bacteriuria. None of our screening tests had a sensitivity and specificity of 100%, whereas we can only refer the pregnant women with positive leucocyte esterase test and significant pyuria to the urine culture.

Chronic pesticide poisoning from persistent low-dose exposures in Ecuadorean floriculture workers: toward validating a low-cost test battery.

PubMed

Breilh, Jaime; Pagliccia, Nino; Yassi, Annalee

2012-01-01

Chronic pesticide poisoning is difficult to detect. We sought to develop a low-cost test battery for settings such as Ecuador's floriculture industry. First we had to develop a case definition; as with all occupational diseases a case had to have both sufficient effective dose and associated health effects. For the former, using canonical discriminant analysis, we found that adding measures of protection and overall environmental stressors to occupational category and duration of exposure was useful. For the latter, factor analysis suggested three distinct manifestations of pesticide poisoning. We then determined sensitivity and specificity of various combinations of symptoms and simple neurotoxicity tests from the Pentox questionnaire, and found that doing so increased sensitivity and specificity compared to use of acethylcholinesterase alone--the current screening standard. While sensitivity and specificity varied with different case definitions, our results support the development of a low-cost test battery for screening in such settings.

Self-rating inventory for posttraumatic stress disorder: review of the psychometric properties of a new brief Dutch screening instrument.

PubMed

Hovens, J E; Bramsen, I; van der Ploeg, H M

2002-06-01

The Self-rating Inventory for Posttraumatic Stress Disorder of 22 items was developed for use with populations without identified traumatic experiences. The inventory has been used extensively in survey research in The Netherlands. This paper examines the psychometric properties. In four different groups (trauma and psychiatric patients, elderly Dutch subjects, former peacekeepers, and medical students) internal consistency, test-retest reliability, concurrent and discriminant validity, and sensitivity and specificity are analyzed. The inventory showed good internal consistency, test-retest reliability, concurrent and discriminant validity, and high sensitivity and specificity. It appears to be valuable for survey research on posttraumatic stress in nonselected populations. As a screening device, high sensitivity for PTSD symptoms is evident even when the traumatic event has not been defined.

Serological and molecular tools to diagnose visceral leishmaniasis: 2-years’ experience of a single center in Northern Italy

PubMed Central

Ortalli, Margherita; Attard, Luciano; Vanino, Elisa; Gaibani, Paolo; Vocale, Caterina; Rossini, Giada; Cagarelli, Roberto; Pierro, Anna; Billi, Patrizia; Mastroianni, Antonio; Di Cesare, Simona; Codeluppi, Mauro; Franceschini, Erica; Melchionda, Fraia; Gramiccia, Marina; Scalone, Aldo; Gentilomi, Giovanna A.; Landini, Maria P.

2017-01-01

The diagnosis of visceral leishmaniasis (VL) remains challenging, due to the limited sensitivity of microscopy, the poor performance of serological methods in immunocompromised patients and the lack of standardization of molecular tests. The aim of this study was to implement a combined diagnostic workflow by integrating serological and molecular tests with standardized clinical criteria. Between July 2013 and June 2015, the proposed workflow was applied to specimens obtained from 94 in-patients with clinical suspicion of VL in the Emilia-Romagna region, Northern Italy. Serological tests and molecular techniques were employed. Twenty-one adult patients (22%) had a confirmed diagnosis of VL by clinical criteria, serology and/or real-time polymerase chain reaction; 4 of these patients were HIV-positive. Molecular tests exhibited higher sensitivity than serological tests for the diagnosis of VL. In our experience, the rK39 immunochromatographic test was insufficiently sensitive for use as a screening test for the diagnosis of VL caused by L. infantum in Italy. However, as molecular tests are yet not standardized, further studies are required to identify an optimal screening test for Mediterranean VL. PMID:28832646

Bias-corrected diagnostic performance of the naked-eye single-tube red-cell osmotic fragility test (NESTROFT): an effective screening tool for beta-thalassemia.

PubMed

Mamtani, Manju; Jawahirani, Anil; Das, Kishor; Rughwani, Vinky; Kulkarni, Hemant

2006-08-01

It is being increasingly recognized that a majority of the countries in the thalassemia-belt need a cost-effective screening program as the first step towards control of thalassemia. Although the naked eye single tube red cell osmotic fragility test (NESTROFT) has been considered to be a very effective screening tool for beta-thalassemia trait, assessment of its diagnostic performance has been affected with the reference test- and verification-bias. Here, we set out to provide estimates of sensitivity and specificity of NESTROFT corrected for these potential biases. We conducted a cross-sectional diagnostic test evaluation study using data from 1563 subjects from Central India with a high prevalence of beta-thalassemia. We used latent class modelling after ensuring its validity to account for the reference test bias and global sensitivity analysis to control the verification bias. We also compared the results of latent class modelling with those of five discriminant indexes. We observed that across a range of cut-offs for the mean corpuscular volume (MCV) and the hemoglobin A2 (HbA2) concentration the average sensitivity and specificity of NESTROFT obtained from latent class modelling was 99.8 and 83.7%, respectively. These estimates were comparable to those characterizing the diagnostic performance of HbA2, which is considered by many as the reference test to detect beta-thalassemia. After correction for the verification bias these estimates were 93.4 and 97.2%, respectively. Combined with the inexpensive and quick disposition of NESTROFT, these results strongly support its candidature as a screening tool-especially in the resource-poor and high-prevalence settings.

Transforming Security Screening With Biometrics

DTIC Science & Technology

2003-04-09

prompted the Defense Advanced Research Projects Agency to experiment with facial recognition technology for identification of known terrorists. While DoD...screening of individuals. Facial recognition technology has been tested to some degree for accessing highly sensitive military areas, but not for...the military can implement facial recognition to screen personnel requesting access to bases and stations, DoD is not likely to use biometrics to

Improvement of screening methods for silicon planar semiconductor devices

NASA Technical Reports Server (NTRS)

Berger, W. M.

1972-01-01

The results of the program for the development of a more sensitive method for selecting silicon planar semiconductor devices for long life applications are reported. The manufacturing technologies (MOS and Bipolar) are discussed along with the screening procedures developed as a result of the tests and evaluations, and the effectiveness of the MOS and Bilayer screening procedures are evaluated.

Military Research ColorDx and Printed Color Vision Tests.

PubMed

Almustanyir, Ali; Hovis, Jeffery K

2015-10-01

To determine the equivalence of the ColorDx Military Research version (mColorDx) test and three printed pseudoisochromatic tests (HRR, Ishihara, and PIPIC) for color vision testing. Participating in the study were 75 color-normals and 47 subjects with red-green color vision defects. Color vision was classified by an anomaloscope. The HRR (4(th) edition), Ishihara 38-plate edition, and PIPIC tests are printed color vision tests, whereas mColorDx test figures were displayed on a calibrated computer desktop monitor. All tests were repeated in about 1 wk. The kappa level of agreement (κ) values with the anomaloscope for screening for each test was 0.96 or greater. The values were statistically identical. Specificity for each test was at least 0.99 and sensitivity was at least 0.95. The repeatability of the screening sections for all tests was very good with κ values greater than 0.95. Deutans tended to miss the tritan screening plates on the HRR and mColorDx tests. The Spearman rank correlation coefficients between the severity of the defect and anomaloscope range was moderate with r = 0.45 for the mColorDx and r = 0.6 for the HRR. Both the mColorDx and HRR had perfect agreement with the anomaloscope in classifying the defects as either protan or deutan. The validity of the four tests for color vision screening was statistically identical; however, the HRR may be preferred because it had the highest sensitivity of 0.99, a specificity of 1.0, and a reasonable correlation between the severity rating of the defect and the anomaloscope range.

Estimating chlamydia screening coverage: a comparison of self-report and health care effectiveness data and information set measures.

PubMed

Khosropour, Christine M; Broad, Jennifer M; Scholes, Delia; Saint-Johnson, Jacquelyn; Manhart, Lisa E; Golden, Matthew R

2014-11-01

Population-based surveys (self-report) and health insurance administrative data (Healthcare Effectiveness Data and Information Set [HEDIS]) are used to estimate chlamydia screening coverage in the United States. Estimates from these methods differ, but few studies have compared these 2 indices in the same population. In 2010, we surveyed a random sample of women aged 18 to 25 years enrolled in a Washington State-managed care organization. Respondents were asked if they were sexually active in last year and if they tested for chlamydia in that time. We linked survey responses to administrative records of chlamydia testing and reproductive/testing services used, which comprise the HEDIS definition of the screened population and the sexually active population, respectively. We compared self-report and HEDIS using 3 outcomes: (1) sexual activity (gold standard = self-report), (2) any chlamydia screening (no gold standard), and (3) within-plan chlamydia screening (gold standard = HEDIS). Of 954 eligible respondents, 377 (40%) completed the survey and consented to administrative record linkage. Chlamydia screening estimates for HEDIS and self-report were 47% and 53%, respectively. The sensitivity and specificity of HEDIS to define sexually active women were 84.8% (95% confidence interval [CI], 79.6%-89.1%) and 63.5% (95% CI, 52.4%-73.7%), respectively. Forty percent of women had a chlamydia test in their administrative record, but 53% self-reported being tested for chlamydia (κ = 0.35); 19% reported out-of-plan chlamydia testing. The sensitivity of self-reported within-plan chlamydia testing was 71.3% (95% CI, 61.0%-80.1%); the specificity was 80.6% (95% CI, 72.6%-87.2%). The Healthcare Effectiveness Data and Information Set does not accurately identify sexually active women and may underestimate chlamydia testing coverage. Self-reported testing may not be an accurate measure of true chlamydial testing coverage.

A comparison of human papillomavirus testing of clinician-collected and self-collected samples during follow-up after screen-and-treat.

PubMed

Taylor, Sylvia; Wang, Chunhui; Wright, Thomas C; Denny, Lynette; Kuhn, Louise

2011-08-15

Screen-and-treat cervical cancer prevention programs based on high-risk human papillomavirus (HPV) testing and cryotherapy have been shown to be effective in resource-limited settings. However, because cryotherapy is not 100% effective, follow-up is needed after treatment to detect post-treatment failures. We compared the test performances of high-risk HPV testing (Hybrid Capture 2) using self-collected and clinician-collected samples as well as cervical cytology for identifying cervical intraepithelial neoplasia grades 2 or 3 or invasive cervical cancer (CIN2+) among women who did (n=812) and did not (n=1858) undergo cryotherapy in a South African screen-and-treat trial. At 6 months after enrolment (and after cryotherapy, if performed), women were tested using all three screening methods and then underwent colposcopy/biopsy. A predefined subset of women (n=1,455) had extended follow-up with colposcopy/biopsy at 12 months. A total of 33 and 91 cases of CIN2+ were detected among treated and untreated women, respectively. The sensitivity of HPV testing using clinician-collected samples and cervical cytology did not differ by treatment status. HPV testing of clinician-collected samples detected the most cases of CIN2+ among both treated (85%) and untreated (91%) women (p=0.31). Cytology (at a cutoff of atypical squamous cells of undetermined significance or greater) detected 76% of cases among both treated and untreated women. However, the sensitivity of HPV testing using self-collected samples was significantly lower among treated versus untreated women (55% vs. 78%, p=0.01). HPV testing using self-collected vaginal specimens may be useful in primary screening but performs poorly for detecting post-treatment failures. Copyright © 2010 UICC.

Relative Performance of HPV and Cytology Components of Cotesting in Cervical Screening.

PubMed

Schiffman, Mark; Kinney, Walter K; Cheung, Li C; Gage, Julia C; Fetterman, Barbara; Poitras, Nancy E; Lorey, Thomas S; Wentzensen, Nicolas; Befano, Brian; Schussler, John; Katki, Hormuzd A; Castle, Philip E

2018-05-01

The main goal of cervical screening programs is to detect and treat precancer before cancer develops. Human papillomavirus (HPV) testing is more sensitive than cytology for detecting precancer. However, reports of rare HPV-negative, cytology-positive cancers are motivating continued use of both tests (cotesting) despite increased testing costs. We quantified the detection of cervical precancer and cancer by cotesting compared with HPV testing alone at Kaiser Permanente Northern California (KPNC), where 1 208 710 women age 30 years and older have undergone triennial cervical cotesting since 2003. Screening histories preceding cervical cancers (n = 623) and precancers (n = 5369) were examined to assess the relative contribution of the cytology and HPV test components in identifying cases. The performances of HPV testing and cytology were compared using contingency table methods, general estimating equation models, and nonparametric statistics; all statistical tests were two-sided. HPV testing identified more women subsequently diagnosed with cancer (P < .001) and precancer (P < .001) than cytology. HPV testing was statistically significantly more likely to be positive for cancer at any time point (P < .001), except within 12 months (P = .10). HPV-negative/cytology-positive results preceded only small fractions of cases of precancer (3.5%) and cancer (5.9%); these cancers were more likely to be regional or distant stage with squamous histopathology than other cases. Given the rarity of cancers among screened women, the contribution of cytology to screening translated to earlier detection of at most five cases per million women per year. Two-thirds (67.9%) of women found to have cancer during 10 years of follow-up at KPNC were detected by the first cotest performed. The added sensitivity of cotesting vs HPV alone for detection of treatable cancer affected extremely few women.

Evaluation of a Rapid Diagnostic Test for Yaws Infection in a Community Surveillance Setting

PubMed Central

Marks, Michael; Goncalves, Adriana; Vahi, Ventis; Sokana, Oliver; Puiahi, Elliot; Zhang, Zaixing; Dalipanda, Tenneth; Bottomley, Christian; Mabey, David; Solomon, Anthony W.

2014-01-01

Yaws is a non-venereal treponemal infection caused by Treponema pallidum ssp. pertenue. The WHO has launched a worldwide control programme, which aims to eradicate yaws by 2020. The development of a rapid diagnostic test (RDT) for serological diagnosis in the isolated communities affected by yaws is a key requirement for the successful implementation of the WHO strategy. We conducted a study to evaluate the utility of the DPP test in screening for yaws, utilizing samples collected as part of a community prevalence survey conducted in the Solomon Islands. 415 serum samples were tested using both traditional syphilis serology (TPPA and quantitative RPR) and the Chembio DPP Syphilis Screen and Confirm RDT. We calculated the sensitivity and specificity of the RDT as compared to gold standard serology. The sensitivity of the RDT against TPPA was 58.5% and the specificity was 97.6%. The sensitivity of the RDT against RPR was 41.7% and the specificity was 95.2%. The sensitivity of the DPP was strongly related to the RPR titre with a sensitivity of 92.0% for an RPR titre of >1/16. Wider access to DPP testing would improve our understanding of worldwide yaws case reporting and the test may play a key role in assessing patients presenting with yaws like lesions in a post-mass drug administration (MDA) setting. PMID:25211018

Evaluation of a rapid diagnostic test for yaws infection in a community surveillance setting.

PubMed

Marks, Michael; Goncalves, Adriana; Vahi, Ventis; Sokana, Oliver; Puiahi, Elliot; Zhang, Zaixing; Dalipanda, Tenneth; Bottomley, Christian; Mabey, David; Solomon, Anthony W

2014-09-01

Yaws is a non-venereal treponemal infection caused by Treponema pallidum ssp. pertenue. The WHO has launched a worldwide control programme, which aims to eradicate yaws by 2020. The development of a rapid diagnostic test (RDT) for serological diagnosis in the isolated communities affected by yaws is a key requirement for the successful implementation of the WHO strategy. We conducted a study to evaluate the utility of the DPP test in screening for yaws, utilizing samples collected as part of a community prevalence survey conducted in the Solomon Islands. 415 serum samples were tested using both traditional syphilis serology (TPPA and quantitative RPR) and the Chembio DPP Syphilis Screen and Confirm RDT. We calculated the sensitivity and specificity of the RDT as compared to gold standard serology. The sensitivity of the RDT against TPPA was 58.5% and the specificity was 97.6%. The sensitivity of the RDT against RPR was 41.7% and the specificity was 95.2%. The sensitivity of the DPP was strongly related to the RPR titre with a sensitivity of 92.0% for an RPR titre of >1/16. Wider access to DPP testing would improve our understanding of worldwide yaws case reporting and the test may play a key role in assessing patients presenting with yaws like lesions in a post-mass drug administration (MDA) setting.

Your Child's Vision

MedlinePlus

... 3½, kids should have eye health screenings and visual acuity tests (tests that measure sharpness of vision) ... eye rubbing extreme light sensitivity poor focusing poor visual tracking (following an object) abnormal alignment or movement ...

Diagnostic methods of TSH in thyroid screening tests.

PubMed

Matyjaszek-Matuszek, Beata; Pyzik, Aleksandra; Nowakowski, Andrzej; Jarosz, Mirosław J

2013-01-01

Reliable and quick thyreologic diagnostics, as well as verification of the effectiveness of the therapy undertaken, is of great importance for the state of health of society. The measurement of plasma TSH is the commonly accepted and most sensitive screening test for primary thyroid disorders, which are the most frequent diseases related to the endocrine glands. At present, the available methods for the determination of TSH are characterized by high sensitivity ≤0.01 µIU/ml and lack of cross-reactivity. However, many drugs and substances, as well as pathological conditions, may affect the TSH level. evaluation of contemporary laboratory methods for the determination of TSH and the principles of interpretation of screening tests. In many countries, the TSH test is the only test performed in the diagnostics of thyroid function; nevertheless, it seems that for genuine and objective assessment of thyroid status the TSH level, together with FT4 level, should be absolutely determined, which allows the differentiation and assessment of the intensity of thyroid function disorders and foresee its consequences. The interpretation of TSH results in screening tests is different in such population groups as: children aged under 14, pregnant women, the elderly, and patients with non-thyroidal illnesses. From among currently used laboratory methods for determination of TSH levels, third generation non-isotopic methods are most frequently recommended, especially the method of immunochemiluminescence.

Performing a urine dipstick test with a clean-catch urine sample is an accurate screening method for urinary tract infections in young infants.

PubMed

Herreros, María Luisa; Tagarro, Alfredo; García-Pose, Araceli; Sánchez, Aida; Cañete, Alfonso; Gili, Pablo

2018-01-01

This study evaluated using urine dipstick tests with the clean-catch method to screen for urinary tract infection (UTI) in febrile infants under 90 days of age. We carried out a comparative diagnostic accuracy study of infants under 90 days old, who were studied for unexplained fever without any source, in the emergency room of a hospital in Madrid from January 2011 to January 2013. We obtained matched samples of urine using two different methods: a clean-catch, standardised stimulation technique and catheterisation collection. The results of the leucocyte esterase test and nitrite test were compared with their urine cultures. We obtained 60 pairs of matched samples. A combined analysis of leukocyte esterase and, or, nitrites yielded a sensitivity of 86% and a specificity of 80% for the diagnosis of UTIs in clean-catch samples. The sensitivity of leukocyte esterase and, or, nitrites in samples obtained by catheterisation were not statistically different to the clean-catch samples (p = 0.592). Performing urine dipstick tests using urine samples obtained by the clean-catch method was an accurate screening test for diagnosing UTIs in febrile infants of less than 90 days old. This provided a good alternative to bladder catheterisation when screening for UTIs. ©2017 Foundation Acta Paediatrica. Published by John Wiley & Sons Ltd.

Reliability and Validity of Observational Risk Screening in Evaluating Dynamic Knee Valgus

PubMed Central

Ekegren, Christina L.; Miller, William C.; Celebrini, Richard G.; Eng, Janice J.; MacIntyre, Donna L.

2012-01-01

Study Design Nonexperimental methodological study. Objectives To determine the interrater and intrarater reliability and validity of using observational risk screening guidelines to evaluate dynamic knee valgus. Background A deficiency in the neuromuscular control of the hip has been identified as a key risk factor for non-contact anterior cruciate ligament (ACL) injury in post pubescent females. This deficiency can manifest itself as a valgus knee alignment during tasks involving hip and knee flexion. There are currently no scientifically tested methods to screen for dynamic knee valgus in the clinic or on the field. Methods Three physiotherapists used observational risk screening guidelines to rate 40 adolescent female soccer players according to their risk of ACL injury. The rating was based on the amount of dynamic knee valgus observed on a drop jump landing. Ratings were evaluated for intrarater and interrater agreement using kappa coefficients. Sensitivity and specificity of ratings were evaluated by comparing observational ratings with measurements obtained using 3-dimensional (3D) motion analysis. Results Kappa coefficients for intrarater and interrater agreement ranged from 0.75 to 0.85, indicating that ratings were reasonably consistent over time and between physiotherapists. Sensitivity values were inadequate, ranging from 67–87%. This indicated that raters failed to detect up to a third of “truly high risk” individuals. Specificity values ranged from 60–72% which was considered adequate for the purposes of the screen. Conclusion Observational risk screening is a practical and cost-effective method of screening for ACL injury risk. Rater agreement and specificity were acceptable for this method but sensitivity was not. To detect a greater proportion of individuals at risk of ACL injury, coaches and clinicians should ensure that they include additional tests for other high risk characteristics in their screening protocols. PMID:19721212

Screening for confabulations with the confabulation screen.

PubMed

Dalla Barba, Gianfranco; Brazzarola, Marta; Marangoni, Sara; La Corte, Valentina

2018-04-24

The objective of this work is to devise and validate a sensitive and specific test for confabulatory impairment. We conceived a screening test for confabulation, the Confabulation Screen (CS), a brief test using 10 questions of episodic memory (EM), where confabulators most frequently confabulate. It was postulated that the CS would predict confabulations not only in EM, but also in the other subordinate structures of personal temporality, namely the present and the future. Thirty confabulating amnesic patients of various aetiologies and 97 normal controls entered the study. Participants were administered the CS and the Confabulation Battery (Dalla Barba, G., & Decaix, C. (2009). "Do you remeber what you did on March 13 1985?" A case study of confabulatory hypermnesia. Cortex, 45(5), 566-574). Confabulations in the CS positively and significantly correlated with confabulations in personal temporality domains of the CB, namely EM, orientation in time and place and episodic plans. Conversely, as expected, they did not correlate with confabulations in impersonal temporality domains of the CB. Consistent with results of previous studies, the most frequently observed type of confabulation in the CS was Habits Confabulation. The CS had high construct validity and good discriminative validity in terms of sensitivity and specificity. Cut-off scores for clinical and research purposes are proposed. The CS provides efficient and valid screening for confabulatory impairment.

Clinical utility of a single-item test for DSM-5 alcohol use disorder among outpatients with anxiety and depressive disorders.

PubMed

Bartoli, Francesco; Crocamo, Cristina; Biagi, Enrico; Di Carlo, Francesco; Parma, Francesca; Madeddu, Fabio; Capuzzi, Enrico; Colmegna, Fabrizia; Clerici, Massimo; Carrà, Giuseppe

2016-08-01

There is a lack of studies testing accuracy of fast screening methods for alcohol use disorder in mental health settings. We aimed at estimating clinical utility of a standard single-item test for case finding and screening of DSM-5 alcohol use disorder among individuals suffering from anxiety and mood disorders. We recruited adults consecutively referred, in a 12-month period, to an outpatient clinic for anxiety and depressive disorders. We assessed the National Institute on Alcohol Abuse and Alcoholism (NIAAA) single-item test, using the Mini- International Neuropsychiatric Interview (MINI), plus an additional item of Composite International Diagnostic Interview (CIDI) for craving, as reference standard to diagnose a current DSM-5 alcohol use disorder. We estimated sensitivity and specificity of the single-item test, as well as positive and negative Clinical Utility Indexes (CUIs). 242 subjects with anxiety and mood disorders were included. The NIAAA single-item test showed high sensitivity (91.9%) and specificity (91.2%) for DSM-5 alcohol use disorder. The positive CUI was 0.601, whereas the negative one was 0.898, with excellent values also accounting for main individual characteristics (age, gender, diagnosis, psychological distress levels, smoking status). Testing for relevant indexes, we found an excellent clinical utility of the NIAAA single-item test for screening true negative cases. Our findings support a routine use of reliable methods for rapid screening in similar mental health settings. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

HPV self-sampling in CIN2+ detection: sensitivity and specificity of different RLU cut-off of HC2 in specimens from 786 women.

PubMed

Bottari, F; Igidbashian, S; Boveri, S; Tricca, A; Gulmini, C; Sesia, M; Spolti, N; Sideri, M; Landoni, F; Sandri, M T

2017-04-01

Mortality for cervical cancer varies between the different regions of the world, with high rates in low-income countries where screening programmes are not present and organised. However, increasing screening coverage is still a priority in all countries: one way to do that is to base screening on self-sampled screening. The success of a self-sampling screening strategy depends on capacity to recruit unscreened women, on the performance and acceptability of the device and on the clinical performance of the high-risk human papillomavirus (HPV) test. This study based on 786 enrolled women investigates the best cut-off value of Hybrid Capture 2 HPV test (HC2) for self-sampled specimens in terms of sensitivity and specificity. In this population, we found that the sensitivity and the specificity for cervical intraepithelial neoplasia grade 2 or more detection of HC2 performed on self-sampled specimens were 82.5% and 82.8%, respectively considering the relative light units (RLU) cut-off value of 1. Increasing the cut-off value the sensitivity decreases and the specificity raises and the best area under the curve for the RLU cut-off value is 1. Our results confirm that the cut-off value of 1 suggested by Qiagen for PreservCyt specimen is the best cut-off value also for self-sampled specimens. 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/.

Simple, rapid, and cost-effective modified Carba NP test for carbapenemase detection among Gram-negative bacteria

PubMed Central

Rudresh, Shoorashetty Manohara; Ravi, Giriyapur Siddappa; Sunitha, Lakshminarayanappa; Hajira, Sadiya Noor; Kalaiarasan, Ellappan; Harish, Belgode Narasimha

2017-01-01

PURPOSE: Detection of carbapenemases among Gram-negative bacteria (GNB) is important for both clinicians and infection control practitioners. The Clinical and Laboratory Standards Institute recommends Carba NP (CNP) as confirmatory test for carbapenemase production. The reagents required for CNP test are costly and hence the test cannot be performed on a routine basis. The present study evaluates modifications of CNP test for rapid detection of carbapenemases among GNB. MATERIALS AND METHODS: The GNB were screened for carbapenemase production using CNP, CarbAcineto NP (CANP), and modified CNP (mCNP) test. A multiplex polymerase chain reaction (PCR) was performed on all the carbapenem-resistant bacteria for carbapenemase genes. The results of three phenotypic tests were compared with PCR. RESULTS: A total of 765 gram negative bacteria were screened for carbapenem resistance. Carbapenem resistance was found in 144 GNB. The metallo-β-lactamases were most common carbapenemases followed by OXA-48-like enzymes. The CANP test was most sensitive (80.6%) for carbapenemases detection. The mCNP test was 62.1% sensitive for detection of carbapenemases. The mCNP, CNP, and CANP tests were equally sensitive (95%) for detection of NDM enzymes among Enterobacteriaceae. The mCNP test had poor sensitivity for detection of OXA-48-like enzymes. CONCLUSION: The mCNP test was rapid, cost-effective, and easily adoptable on routine basis. The early detection of carbapenemases using mCNP test will help in preventing the spread of multidrug-resistant organisms in the hospital settings. PMID:28966495

Simple, rapid, and cost-effective modified Carba NP test for carbapenemase detection among Gram-negative bacteria.

PubMed

Rudresh, Shoorashetty Manohara; Ravi, Giriyapur Siddappa; Sunitha, Lakshminarayanappa; Hajira, Sadiya Noor; Kalaiarasan, Ellappan; Harish, Belgode Narasimha

2017-01-01

Detection of carbapenemases among Gram-negative bacteria (GNB) is important for both clinicians and infection control practitioners. The Clinical and Laboratory Standards Institute recommends Carba NP (CNP) as confirmatory test for carbapenemase production. The reagents required for CNP test are costly and hence the test cannot be performed on a routine basis. The present study evaluates modifications of CNP test for rapid detection of carbapenemases among GNB. The GNB were screened for carbapenemase production using CNP, CarbAcineto NP (CANP), and modified CNP (mCNP) test. A multiplex polymerase chain reaction (PCR) was performed on all the carbapenem-resistant bacteria for carbapenemase genes. The results of three phenotypic tests were compared with PCR. A total of 765 gram negative bacteria were screened for carbapenem resistance. Carbapenem resistance was found in 144 GNB. The metallo-β-lactamases were most common carbapenemases followed by OXA-48-like enzymes. The CANP test was most sensitive (80.6%) for carbapenemases detection. The mCNP test was 62.1% sensitive for detection of carbapenemases. The mCNP, CNP, and CANP tests were equally sensitive (95%) for detection of NDM enzymes among Enterobacteriaceae. The mCNP test had poor sensitivity for detection of OXA-48-like enzymes. The mCNP test was rapid, cost-effective, and easily adoptable on routine basis. The early detection of carbapenemases using mCNP test will help in preventing the spread of multidrug-resistant organisms in the hospital settings.

Population screening for coeliac disease in primary care by district nurses using a rapid antibody test: diagnostic accuracy and feasibility study

PubMed Central

2007-01-01

Objective To evaluate the feasibility and diagnostic accuracy of screening for coeliac disease by rapid detection of IgA antibodies to tissue transglutaminase performed in primary care. Design District nurses screened 6 year old children using rapid antibody testing of finger prick blood. They also collected capillary blood samples for laboratory determination of IgA and IgG antibodies to endomysium and IgA antibodies to tissue transglutaminase. Children with positive rapid test results were directly sent for biopsy of the small intestine. Setting Primary care in Jász-Nagykun-Szolnok county, Hungary. Participants 2690 children (77% of 6 year olds living in the county) and 120 nurses. Main outcome measures Positivity for antibodies to endomysium or transglutaminase in the laboratory and coeliac disease confirmed at biopsy. Results 37 children (1.4%, 95% confidence interval 0.9% to 1.8%) had biopsy confirmed coeliac disease. Only five of these children had been diagnosed clinically before screening. Rapid testing had a 78.1% sensitivity (70.0% to 89.3%) and 100% specificity (88.4% to 100%) for a final diagnosis of coeliac disease by biopsy. Sensitivity was 65.1% (50.2% to 77.6%) and specificity was 100% (99.8% to 100%) compared with combined results of IgA and IgG laboratory tests. Trained laboratory workers detected 30 of the 31 newly diagnosed IgA competent patients with the rapid test kit used blindly. Median time to biopsy after a positive rapid test result was significantly shorter (20 days, range 4-148) than after a positive laboratory result (142 days, 70-256; P<0.001). Children with coeliac disease detected at screening were smaller and had worse health status than their peers but they improved on a gluten-free diet. Conclusions A simple rapid antibody test enabled primary care nurses to detect patients with coeliac disease in the community who were not picked up in clinical care. Extra training is needed to improve sensitivity. PMID:18063612

Screening tests: a review with examples

PubMed Central

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

The computerized adaptive diagnostic test for major depressive disorder (CAD-MDD): a screening tool for depression.

PubMed

Gibbons, Robert D; Hooker, Giles; Finkelman, Matthew D; Weiss, David J; Pilkonis, Paul A; Frank, Ellen; Moore, Tara; Kupfer, David J

2013-07-01

To develop a computerized adaptive diagnostic screening tool for depression that decreases patient and clinician burden and increases sensitivity and specificity for clinician-based DSM-IV diagnosis of major depressive disorder (MDD). 656 individuals with and without minor and major depression were recruited from a psychiatric clinic and a community mental health center and through public announcements (controls without depression). The focus of the study was the development of the Computerized Adaptive Diagnostic Test for Major Depressive Disorder (CAD-MDD) diagnostic screening tool based on a decision-theoretical approach (random forests and decision trees). The item bank consisted of 88 depression scale items drawn from 73 depression measures. Sensitivity and specificity for predicting clinician-based Structured Clinical Interview for DSM-IV Axis I Disorders diagnoses of MDD were the primary outcomes. Diagnostic screening accuracy was then compared to that of the Patient Health Questionnaire-9 (PHQ-9). An average of 4 items per participant was required (maximum of 6 items). Overall sensitivity and specificity were 0.95 and 0.87, respectively. For the PHQ-9, sensitivity was 0.70 and specificity was 0.91. High sensitivity and reasonable specificity for a clinician-based DSM-IV diagnosis of depression can be obtained using an average of 4 adaptively administered self-report items in less than 1 minute. Relative to the currently used PHQ-9, the CAD-MDD dramatically increased sensitivity while maintaining similar specificity. As such, the CAD-MDD will identify more true positives (lower false-negative rate) than the PHQ-9 using half the number of items. Inexpensive (relative to clinical assessment), efficient, and accurate screening of depression in the settings of primary care, psychiatric epidemiology, molecular genetics, and global health are all direct applications of the current system. © Copyright 2013 Physicians Postgraduate Press, Inc.

Combined use of fasting plasma glucose and glycated hemoglobin A1c in the screening of diabetes and impaired glucose tolerance.

PubMed

Hu, Yaomin; Liu, Wei; Chen, Yawen; Zhang, Ming; Wang, Lihua; Zhou, Huan; Wu, Peihong; Teng, Xiangyu; Dong, Ying; Zhou, Jia wen; Xu, Hua; Zheng, Jun; Li, Shengxian; Tao, Tao; Hu, Yumei; Jia, Yun

2010-09-01

The aim of this study is to assess the validity of combined use of fasting plasma glucose (FPG) and glycated hemoglobin A1c (HbA1c) as screening tests for diabetes and impaired glucose tolerance (IGT) in high-risk subjects. A total of 2,298 subjects were included. All subjects underwent a 75-g oral glucose tolerance test (OGTT) and HbA1c measurement. Receiver operating characteristic curve (ROC curve) analysis was used to examine the sensitivity and specificity of FPG and HbA1c for detecting diabetes and IGT, which was defined according to the 1999 World Health Organization (WHO) criteria. (1) Based on the ROC curve, the optimal cut point of FPG related to diabetes diagnosed by OGTT was 6.1 mmol/l that was associated with a sensitivity and specificity of 81.5 and 81.0%, respectively; The optimal cut point of HbA1c related to diabetes diagnosed by OGTT was 6.1%, which was associated with a sensitivity and specificity of 81.0 and 81.0%, respectively; The screening model using FPG > or = 6.1 mmol/l or HbA1c > or = 6.1% had sensitivity of 96.5% for detecting undiagnosed diabetes; the screening model using FPG > or = 6.1 mmol/l and HbA1c > or = 6.1% had specificity of 96.3% for detecting undiagnosed diabetes. (2) Based on the ROC curve, the optimal cut point of FPG related to IGT diagnosed by OGTT was 5.6 mmol/l that was associated with a sensitivity and specificity of 64.1 and 65.4%, respectively; The optimal cut point of HbA1c related to IGT diagnosed by OGTT was 5.6%, which was associated with a sensitivity and specificity of 66.2 and 51.0%, respectively; The screening model using FPG > or = 5.6 mmol/l or HbA1c > or = 5.6% had sensitivity of 87.9% for detecting undiagnosed IGT; The screening model using FPG > or = 5.6 mmol/l and HbA1c > or = 5.6% had specificity of 82.4% for detecting undiagnosed IGT. Compared with FPG or HbA1c alone, the simultaneous measurement of FPG and HbA1c (FPG and/or HbA1C) might be a more sensitive and specific screening tool for identifying high-risk individuals with diabetes and IGT at an early stage.

Parameter screening: the use of a dummy parameter to identify non-influential parameters in a global sensitivity analysis

NASA Astrophysics Data System (ADS)

Khorashadi Zadeh, Farkhondeh; Nossent, Jiri; van Griensven, Ann; Bauwens, Willy

2017-04-01

Parameter estimation is a major concern in hydrological modeling, which may limit the use of complex simulators with a large number of parameters. To support the selection of parameters to include in or exclude from the calibration process, Global Sensitivity Analysis (GSA) is widely applied in modeling practices. Based on the results of GSA, the influential and the non-influential parameters are identified (i.e. parameters screening). Nevertheless, the choice of the screening threshold below which parameters are considered non-influential is a critical issue, which has recently received more attention in GSA literature. In theory, the sensitivity index of a non-influential parameter has a value of zero. However, since numerical approximations, rather than analytical solutions, are utilized in GSA methods to calculate the sensitivity indices, small but non-zero indices may be obtained for the indices of non-influential parameters. In order to assess the threshold that identifies non-influential parameters in GSA methods, we propose to calculate the sensitivity index of a "dummy parameter". This dummy parameter has no influence on the model output, but will have a non-zero sensitivity index, representing the error due to the numerical approximation. Hence, the parameters whose indices are above the sensitivity index of the dummy parameter can be classified as influential, whereas the parameters whose indices are below this index are within the range of the numerical error and should be considered as non-influential. To demonstrated the effectiveness of the proposed "dummy parameter approach", 26 parameters of a Soil and Water Assessment Tool (SWAT) model are selected to be analyzed and screened, using the variance-based Sobol' and moment-independent PAWN methods. The sensitivity index of the dummy parameter is calculated from sampled data, without changing the model equations. Moreover, the calculation does not even require additional model evaluations for the Sobol' method. A formal statistical test validates these parameter screening results. Based on the dummy parameter screening, 11 model parameters are identified as influential. Therefore, it can be denoted that the "dummy parameter approach" can facilitate the parameter screening process and provide guidance for GSA users to define a screening-threshold, with only limited additional resources. Key words: Parameter screening, Global sensitivity analysis, Dummy parameter, Variance-based method, Moment-independent method

Clinician Suspicion of an Alcohol Problem: An Observational Study From the AAFP National Research Network

PubMed Central

Vinson, Daniel C.; Turner, Barbara J.; MSED; Manning, Brian K.; Galliher, James M.

2013-01-01

PURPOSE In clinical practice, detection of alcohol problems often relies on clinician suspicion instead of using a screening instrument. We assessed the sensitivity, specificity, and predictive values of clinician suspicion compared with screening-detected alcohol problems in patients. METHODS We undertook a cross-sectional study of 94 primary care clinicians’ office visits. Brief questionnaires were completed separately after a visit by both clinicians and eligible patients. The patient’s anonymous exit questionnaire screened for hazardous drinking based on the Alcohol Use Disorders Identification Test-Consumption (AUDIT-C) and for harmful drinking (alcohol abuse or dependence) based on 2 questions from the Diagnostic and Statistical Manual of Mental Disorders. After the visit, clinicians responded to the question, “Does this patient have problems with alcohol?” with answer options including “yes, hazardous drinking” and “yes, alcohol abuse or dependence.” Analyses assessed the associations between patients’ responses to screening questions and clinician’s suspicions. RESULTS Of 2,518 patients with an office visit, 2,173 were eligible, and 1,699 (78%) completed the exit questionnaire. One hundred seventy-one (10.1%) patients had a positive screening test for hazardous drinking (an AUDIT-C score of 5 or greater) and 64 (3.8%) for harmful drinking. Clinicians suspected alcohol problems in 81 patients (hazardous drinking in 37, harmful drinking in 40, and both in 4). The sensitivity of clinician suspicion of either hazardous or harmful drinking was 27% and the specificity was 98%. Positive and negative predictive values were 62% and 92%, respectively. CONCLUSION Clinician suspicion of alcohol problems had poor sensitivity but high specificity for identifying patients who had a positive screening test for alcohol problems. These data support the routine use of a screening tool to supplement clinicians’ suspicions, which already provide reasonable positive predictive value. PMID:23319506

Lessons learned from the use of HRP-2 based rapid diagnostic test in community-wide screening and treatment of asymptomatic carriers of Plasmodium falciparum in Burkina Faso.

PubMed

Tiono, Alfred B; Ouédraogo, Alphonse; Diarra, Amidou; Coulibaly, Sam; Soulama, Issiaka; Konaté, Amadou T; Barry, Aïssata; Mukhopadhyay, Amitava; Sirima, Sodiomon B; Hamed, Kamal

2014-01-27

Rapid diagnostic tests (RDTs) are immune chromatographic tests targeting antigens of one or more Plasmodium species and offer the potential to extend accurate malaria diagnosis in endemic areas. In this study, the performance of Plasmodium falciparum-specific histidine-rich protein-2 (PfHRP-2) RDT in the detection of asymptomatic carriers from a hyperendemic region of Burkina Faso was compared with microscopy to gain further insight on its relevance in community-based interventions. The performance of HRP-2 test was evaluated in terms of sensitivity, specificity, positive and negative predictive values, discordant values, likelihood ratios, accuracy, and precision using microscopy as the 'gold standard'. This analysis was carried out in a controlled, parallel, cluster-randomized (18 clusters; 1:1) study in children and adults. The effect of systematic treatment of P. falciparum asymptomatic carriers during three consecutive monthly community screening campaigns on the incidence of symptomatic malaria episodes over a 12-month period was compared with no treatment of asymptomatic carriers. Sensitivity of HRP-2 test in asymptomatic carriers was higher in campaign 1 (92.4%) when compared to campaign 2 (84.0%) and campaign 3 (77.8%). The sensitivity of HRP-2 test increased as parasite density increased across all the age groups. Highest sensitivity (≥97.0%) was recorded at parasite densities of 1,000-4,999/μl, except for children aged 10 to 14 years. The specificity of HRP-2 test was comparable across age groups and highest in campaign 3 (95.9%). The negative predictive values were high across the three campaigns (≥92.7%) while the positive predictive values ranged from 23.2 to 73.8%. False-positive and false-negative rates were high in campaign 1 and campaign 3, respectively. The performance of HRP-2 test in detecting asymptomatic carriers of P. falciparum varied by age and parasite density. Although the use of HRP-2 test is beneficial for the diagnosis of acute malaria, its low sensitivity in screening asymptomatic carriers may limit its utility in pre-elimination interventional settings. The use of a practical and more sensitive test such as loop-mediated isothermal amplification in combination with a cost effective HRP-2 test may be worth exploring in such settings.

Receiver operating characteristic analysis of prediction for gastric cancer development using serum pepsinogen and Helicobacter pylori antibody tests.

PubMed

Hamashima, Chisato; Sasazuki, Shizuka; Inoue, Manami; Tsugane, Shoichiro

2017-03-09

Chronic Helicobacter pylori infection plays a central role in the development of gastric cancer as shown by biological and epidemiological studies. The H. pylori antibody and serum pepsinogen (PG) tests have been anticipated to predict gastric cancer development. We determined the predictive sensitivity and specificity of gastric cancer development using these tests. Receiver operating characteristic analysis was performed, and areas under the curve were estimated. The predictive sensitivity and specificity of gastric cancer development were compared among single tests and combined methods using serum pepsinogen and H. pylori antibody tests. From a large-scale population-based cohort of over 100,000 subjects followed between 1990 and 2004, 497 gastric cancer subjects and 497 matched healthy controls were chosen. The predictive sensitivity and specificity were low in all single tests and combination methods. The highest predictive sensitivity and specificity were obtained for the serum PG I/II ratio. The optimal PG I/II cut-off values were 2.5 and 3.0. At a PG I/II cut-off value of 3.0, the sensitivity was 86.9% and the specificity was 39.8%. Even if three biomarkers were combined, the sensitivity was 97.2% and the specificity was 21.1% when the cut-off values were 3.0 for PG I/II, 70 ng/mL for PG I, and 10.0 U/mL for H. pylori antibody. The predictive accuracy of gastric cancer development was low with the serum pepsinogen and H. pylori antibody tests even if these tests were combined. To adopt these biomarkers for gastric cancer screening, a high specificity is required. When these tests are adopted for gastric cancer screening, they should be carefully interpreted with a clear understanding of their limitations.

Performance of the dipstick screening test as a predictor of negative urine culture

PubMed Central

Marques, Alexandre Gimenes; Doi, André Mario; Pasternak, Jacyr; Damascena, Márcio dos Santos; França, Carolina Nunes; Martino, Marinês Dalla Valle

2017-01-01

ABSTRACT Objective To investigate whether the urine dipstick screening test can be used to predict urine culture results. Methods A retrospective study conducted between January and December 2014 based on data from 8,587 patients with a medical order for urine dipstick test, urine sediment analysis and urine culture. Sensitivity, specificity, positive and negative predictive values were determined and ROC curve analysis was performed. Results The percentage of positive cultures was 17.5%. Nitrite had 28% sensitivity and 99% specificity, with positive and negative predictive values of 89% and 87%, respectively. Leukocyte esterase had 79% sensitivity and 84% specificity, with positive and negative predictive values of 51% and 95%, respectively. The combination of positive nitrite or positive leukocyte esterase tests had 85% sensitivity and 84% specificity, with positive and negative predictive values of 53% and 96%, respectively. Positive urinary sediment (more than ten leukocytes per microliter) had 92% sensitivity and 71% specificity, with positive and negative predictive values of 40% and 98%, respectively. The combination of nitrite positive test and positive urinary sediment had 82% sensitivity and 99% specificity, with positive and negative predictive values of 91% and 98%, respectively. The combination of nitrite or leukocyte esterase positive tests and positive urinary sediment had the highest sensitivity (94%) and specificity (84%), with positive and negative predictive values of 58% and 99%, respectively. Based on ROC curve analysis, the best indicator of positive urine culture was the combination of positives leukocyte esterase or nitrite tests and positive urinary sediment, followed by positives leukocyte and nitrite tests, positive urinary sediment alone, positive leukocyte esterase test alone, positive nitrite test alone and finally association of positives nitrite and urinary sediment (AUC: 0.845, 0.844, 0.817, 0.814, 0.635 and 0.626, respectively). Conclusion A negative urine culture can be predicted by negative dipstick test results. Therefore, this test may be a reliable predictor of negative urine culture. PMID:28444086

The Abbott RealTime High Risk HPV test is a clinically validated human papillomavirus assay for triage in the referral population and use in primary cervical cancer screening in women 30 years and older: a review of validation studies.

PubMed

Poljak, Mario; Oštrbenk, Anja

2013-01-01

Human papillomavirus (HPV) testing has become an essential part of current clinical practice in the management of cervical cancer and precancerous lesions. We reviewed the most important validation studies of a next-generation real-time polymerase chain reaction-based assay, the RealTime High Risk HPV test (RealTime)(Abbott Molecular, Des Plaines, IL, USA), for triage in referral population settings and for use in primary cervical cancer screening in women 30 years and older published in peer-reviewed journals from 2009 to 2013. RealTime is designed to detect 14 high-risk HPV genotypes with concurrent distinction of HPV-16 and HPV-18 from 12 other HPV genotypes. The test was launched on the European market in January 2009 and is currently used in many laboratories worldwide for routine detection of HPV. We concisely reviewed validation studies of a next-generation real-time polymerase chain reaction (PCR)-based assay: the Abbott RealTime High Risk HPV test. Eight validation studies of RealTime in referral settings showed its consistently high absolute clinical sensitivity for both CIN2+ (range 88.3-100%) and CIN3+ (range 93.0-100%), as well as comparative clinical sensitivity relative to the currently most widely used HPV test: the Qiagen/Digene Hybrid Capture 2 HPV DNA Test (HC2). Due to the significantly different composition of the referral populations, RealTime absolute clinical specificity for CIN2+ and CIN3+ varied greatly across studies, but was comparable relative to HC2. Four validation studies of RealTime performance in cervical cancer screening settings showed its consistently high absolute clinical sensitivity for both CIN2+ and CIN3+, as well as comparative clinical sensitivity and specificity relative to HC2 and GP5+/6+ PCR. RealTime has been extensively evaluated in the last 4 years. RealTime can be considered clinically validated for triage in referral population settings and for use in primary cervical cancer screening in women 30 years and older.

Virtual daily living test to screen for mild cognitive impairment using kinematic movement analysis

PubMed Central

Seo, Kyoungwon; Kim, Jae-kwan; Oh, Dong Hoon

2017-01-01

Questionnaires or computer-based tests for assessing activities of daily living are well-known approaches to screen for mild cognitive impairment (MCI). However, questionnaires are subjective and computerized tests only collect simple performance data with conventional input devices such as a mouse and keyboard. This study explored the validity and discriminative power of a virtual daily living test as a new diagnostic approach to assess MCI. Twenty-two healthy controls and 20 patients with MCI were recruited. The virtual daily living test presents two complex daily living tasks in an immersive virtual reality environment. The tasks were conducted based on subject body movements and detailed behavioral data (i.e., kinematic measures) were collected. Performance in both the proposed virtual daily living test and conventional neuropsychological tests for patients with MCI was compared to healthy controls. Kinematic measures considered in this study, such as body movement trajectory, time to completion, and speed, classified patients with MCI from healthy controls, F(8, 33) = 5.648, p < 0.001, η2 = 0.578. When both hand and head speed were employed in conjunction with the immediate free-recall test, a conventional neuropsychological test, the discrimination power for screening MCI was significantly improved to 90% sensitivity and 95.5% specificity (cf. the immediate free-recall test alone has 80% sensitivity and 77.3% specificity). Inclusion of the kinematic measures in screening for MCI significantly improved the classification of patients with MCI compared to the healthy control group, Wilks’ Lambda = 0.451, p < 0.001. PMID:28738088

Reevaluation of confirmatory tests for human T-cell leukemia virus Type 1 using a luciferase immunoprecipitation system in blood donors.

PubMed

Furuta, Rika A; Ma, Guangyong; Matsuoka, Masao; Otani, Satoshi; Matsukura, Harumichi; Hirayama, Fumiya

2015-04-01

Recently, Japanese Red Cross blood centers have changed the confirmatory test method from an indirect immunofluorescence (IF) technique to Western blotting (WB) for antibodies against human T-cell leukemia virus Type 1 (HTLV-1). In this study, these HTLV-1 tests were assessed using another sensitive method, that is, a luciferase immunoprecipitation system (LIPS), to identify a better confirmatory test for HTLV-1 infection. Plasma samples from 54 qualified donors and 114 HTLV-1 screening-positive donors were tested by LIPS for antibodies against HTLV-1 Gag, Tax, Env, and HBZ recombinant proteins. The donors were categorized into six groups, namely, (Group I) qualified donors, screening positive; (Group II) IF positive; (Group III) IF negative; (Group IV) WB positive; (Group V) WB negative; and (Group VI) screening positive in the previous blood donation, but WB-indeterminate during this study period. In Groups II and IV, all plasma samples tested positive by LIPS for antibodies against Gag and Env proteins. In Group V, all samples tested negative by LIPS, whereas some Group III samples reacted with single or double antigens in LIPS. In Group VI, the LIPS test identified a donor with suspected HTLV-1 infection. The first case of a blood donor with plasma that reacted with HBZ was identified by LIPS. Reevaluation of the current HTLV-1 screening method using the LIPS test showed that both confirmatory tests had similar sensitivity and specificity only when WB indeterminate results were eliminated. LIPS is a promising method for detecting and characterizing HTLV-1 antibodies. © 2014 AABB.

A comparison of the absorbed fluorescent treponemal antibody (FTA-ABS) test and other screening tests for treponemal disease in patients attending a venereal disease clinic.

PubMed

Wilkinson, A E; Scrimgeour, G; Rodin, P

1972-05-01

Screening tests-absorbed fluorescent treponemal (FTA-ABS), the Reiter protein complement-fixation (RPCFT), VDRL slide test, automated reagin-and cardiolipin Wassermann reaction-were carried out on 1922 consecutive new patients attending the Whitechapel Clinic over a three-month period.Taking the FTA-ABS test results as an index, the most efficient combination of conventional tests was found to be the RPCFT and automated reagin test. The cardiolipin WR proved to be under-sensitive and of little value compared with the other tests.Forty-two per cent of the 107 sera reactive in the FTA-ABS test were not detected by the RPCFT or ART tests. An assessment based on the TPI test results and clinical findings in these patients is presented. The scope and limitations of the FTA-ABS test as a screening procedure are discussed.

Utility of bioassays (lettuce, red clover, red fescue, Microtox, MetSTICK, Hyalella, bait lamina) in ecological risk screening of acid metal (Zn) contaminated soil.

PubMed

Chapman, E Emily V; Hedrei Helmer, Stephanie; Dave, Göran; Murimboh, John D

2012-06-01

The objective of this study was to assess selected bioassays and ecological screening tools for their suitability in a weight of evidence risk screening process of acidic metal contaminated soil. Intact soil cores were used for the tests, which minimizes changes in pH and metal bioavailability that may result from homogenization and drying of the soil. Soil cores were spiked with ZnCl(2) or CaCl(2). Leachate collected from the soil cores was used to account for the exposure pathways through pore water and groundwater. Tests assessed included MetSTICK in soil cores and Microtox in soil leachate, lettuce (Lactuca sativa), red fescue (Festuca rubra) and red clover (Trifolium pratense) in the soil cores and lettuce and red clover in soil leachate, Hyallella azteca in soil leachate, and an ecological soil function test using Bait Lamina in soil cores. Microtox, H. azteca, lettuce and red fescue showed higher sensitivity to low pH than to Zn concentrations and are therefore not recommended as tests on intact acidic soil cores and soil leachate. The Bait Lamina test appeared sensitive to pH levels below 3.7 but should be investigated further as a screening tool in less acidic soils. Among the bioassays, the MetSTICK and the T. pratense bioassays in soil cores were the most sensitive to Zn, with the lowest nominal NOEC of 200 and 400mg Zn/kg d.w., respectively. These bioassays were also tolerant of low pH, which make them suitable for assessing hazards of metal contaminated acid soils. Copyright © 2012 Elsevier Inc. All rights reserved.

Impact of normalization methods on high-throughput screening data with high hit rates and drug testing with dose-response data.

PubMed

Mpindi, John-Patrick; Swapnil, Potdar; Dmitrii, Bychkov; Jani, Saarela; Saeed, Khalid; Wennerberg, Krister; Aittokallio, Tero; Östling, Päivi; Kallioniemi, Olli

2015-12-01

Most data analysis tools for high-throughput screening (HTS) seek to uncover interesting hits for further analysis. They typically assume a low hit rate per plate. Hit rates can be dramatically higher in secondary screening, RNAi screening and in drug sensitivity testing using biologically active drugs. In particular, drug sensitivity testing on primary cells is often based on dose-response experiments, which pose a more stringent requirement for data quality and for intra- and inter-plate variation. Here, we compared common plate normalization and noise-reduction methods, including the B-score and the Loess a local polynomial fit method under high hit-rate scenarios of drug sensitivity testing. We generated simulated 384-well plate HTS datasets, each with 71 plates having a range of 20 (5%) to 160 (42%) hits per plate, with controls placed either at the edge of the plates or in a scattered configuration. We identified 20% (77/384) as the critical hit-rate after which the normalizations started to perform poorly. Results from real drug testing experiments supported this estimation. In particular, the B-score resulted in incorrect normalization of high hit-rate plates, leading to poor data quality, which could be attributed to its dependency on the median polish algorithm. We conclude that a combination of a scattered layout of controls per plate and normalization using a polynomial least squares fit method, such as Loess helps to reduce column, row and edge effects in HTS experiments with high hit-rates and is optimal for generating accurate dose-response curves. john.mpindi@helsinki.fi. Supplementary information: R code and Supplementary data are available at Bioinformatics online. © The Author 2015. Published by Oxford University Press.

Genomic tests for ovarian cancer detection and management.

PubMed

Myers, Evan R; Havrilesky, Laura J; Kulasingam, Shalini L; Sanders, Gillian D; Cline, Kathryn E; Gray, Rebecca N; Berchuck, Andrew; McCrory, Douglas C

2006-10-01

To assess the evidence that the use of genomic tests for ovarian cancer screening, diagnosis, and treatment leads to improved outcomes. PubMed and reference lists of recent reviews. We evaluated tests for: (a) single gene products; (b) genetic variations affecting risk of ovarian cancer; (c) gene expression; and (d) proteomics. For tests covered in recent evidence reports (cancer antigen 125 [CA-125] and breast cancer genes 1 and 2 [BRCA1/2]), we added studies published subsequent to the reports. We sought evidence on: (a) the analytic performance of tests in clinical laboratories; (b) the sensitivity and specificity of tests in different patient populations; (c) the clinical impact of testing in asymptomatic women, women with suspected ovarian cancer, and women with diagnosed ovarian cancer; (d) the harms of genomic testing; and (e) the impact of direct-to-consumer and direct-to-physician advertising on appropriate use of tests. We also constructed a computer simulation model to test the impact of different assumptions about ovarian cancer natural history on the relative effectiveness of different strategies. There are reasonable data on the clinical laboratory performance of most radioimmunoassays, but the majority of the data on other genomic tests comes from research laboratories. Genomic test sensitivity/specificity estimates are limited by small sample sizes, spectrum bias, and unrealistically large prevalences of ovarian cancer; in particular, estimates of positive predictive values derived from most of the studies are substantially higher than would be expected in most screening or diagnostic settings. We found no evidence relevant to the question of the impact of genomic tests on health outcomes in asymptomatic women. Although there is a relatively large literature on the association of test results and various clinical outcomes, the clinical utility of changing management based on these results has not been evaluated. We found no evidence that genomic tests for ovarian cancer have unique harms beyond those common to other tests for genetic susceptibility or other tests used in screening, diagnosis, and management of ovarian cancer. Studies of a direct-to-consumer campaign for BRCA1/2 testing suggest increased utilization, but the effect on "appropriateness" was unclear. Model simulations suggest that annual screening, even with a highly sensitive test, will not reduce ovarian cancer mortality by more than 50 percent; frequent screening has a very low positive predictive value, even with a highly specific test. Although research remains promising, adaptation of genomic tests into clinical practice must await appropriately designed and powered studies in relevant clinical settings.

Imaging work-up for screening of paraganglioma and pheochromocytoma in SDHx mutation carriers: a multicenter prospective study from the PGL.EVA Investigators.

PubMed

Gimenez-Roqueplo, Anne-Paule; Caumont-Prim, Aurore; Houzard, Claire; Hignette, Chantal; Hernigou, Anne; Halimi, Philippe; Niccoli, Patricia; Leboulleux, Sophie; Amar, Laurence; Borson-Chazot, Françoise; Cardot-Bauters, Catherine; Delemer, Brigitte; Chabolle, Frédéric; Coupier, Isabelle; Libé, Rossella; Peitzsch, Mirko; Peyrard, Séverine; Tenenbaum, Florence; Plouin, Pierre-François; Chatellier, Gilles; Rohmer, Vincent

2013-01-01

Recommendations have not been established concerning imaging to screen SDHx mutation carriers for paraganglioma and pheochromocytoma. Our objective was to compare the performance of gadolinium-enhanced magnetic resonance angiography, contrast-enhanced computed tomography, and [(123)I]metaiodo-benzylguanidine and somatostatin receptor scintigraphies for detecting head and neck and thoracic-abdominal-pelvic paragangliomas in SDHx mutation carriers. We conducted a prospective, multicenter study from June 2005 to December 2009 at 23 French medical centers. A total of 238 index cases or relatives carrying mutations in SDHD, SDHB, or SDHC genes were included. Images obtained by each technique were analyzed blind, without knowledge of results from other tests, first in each local center and then centrally. We evaluated sensitivity, specificity, and likelihood ratios for individual and combinations of tests, the gold standard being the consensus of an expert committee. Two hundred two tumors were diagnosed in 96 subjects. At local assessment, the sensitivity of anatomical imaging for detecting all tumors was higher (85.7%) than that of both scintigraphic techniques (42.7% for [(123)I]metaiodo-benzylguanidine and 69.5% for somatostatin receptor scintigraphy), except for thoracic localizations where somatostatin receptor scintigraphy was more sensitive (61.5 vs. 46.2% for anatomical imaging and 30.8% for [(123)I]metaiodo-benzylguanidine scintigraphy). The best diagnostic performance during local assessment was obtained by combining anatomical imaging tests and somatostatin receptor scintigraphy (sensitivity 91.7%). Central assessment significantly increased the sensitivity (98.6%) of tests in combination. In routine practice, the imaging work-up for screening SDHx mutation carriers should include thoraco-abdomino-pelvic computed tomography, head and neck magnetic angiography, and somatostatin receptor scintigraphy. Expert centralized image assessment is recommended.

Portable acuity screening for any school: validation of patched HOTV with amblyopic patients and Bangerter normals.

PubMed

Tsao Wu, Maya; Armitage, M Diane; Trujillo, Claire; Trujillo, Anna; Arnold, Laura E; Tsao Wu, Lauren; Arnold, Robert W

2017-12-04

We needed to validate and calibrate our portable acuity screening tools so amblyopia could be detected quickly and effectively at school entry. Spiral-bound flip cards and download pdf surround HOTV acuity test box with critical lines were combined with a matching card. Amblyopic patients performed critical line, then threshold acuity which was then compared to patched E-ETDRS acuity. 5 normal subjects wore Bangerter foil goggles to simulate blur for comparative validation. The 31 treated amblyopic eyes showed: logMAR HOTV = 0.97(logMAR E-ETDRS)-0.04 r2 = 0.88. All but two (6%) fell less than 2 lines difference. The five showed logMAR HOTV = 1.09 ((logMAR E-ETDRS) + .15 r2 = 0.63. The critical-line, test box was 98% efficient at screening within one line of 20/40. These tools reliably detected acuity in treated amblyopic patients and Bangerter blurred normal subjects. These free and affordable tools provide sensitive screening for amblyopia in children from public, private and home schools. Changing "pass" criteria to 4 out of 5 would improve sensitivity with somewhat slower testing for all students.

Genotyping for Human Papillomavirus (HPV) 16/18/52/58 Has a Higher Performance than HPV16/18 Genotyping in Triaging Women with Positive High-risk HPV Test in Northern Thailand

PubMed Central

Khunamornpong, Surapan; Settakorn, Jongkolnee; Sukpan, Kornkanok; Suprasert, Prapaporn; Srisomboon, Jatupol; Intaraphet, Suthida; Siriaunkgul, Sumalee

2016-01-01

Background Testing for high-risk human papillomavirus DNA (HPV test) has gained increasing acceptance as an alternative method to cytology in cervical cancer screening. Compared to cytology, HPV test has a higher sensitivity for the detection of histologic high-grade squamous intraepithelial lesion or worse (HSIL+), but this could lead to a large colposcopy burden. Genotyping for HPV16/18 has been recommended in triaging HPV-positive women. This study was aimed to evaluate the screening performance of HPV testing and the role of genotyping triage in Northern Thailand. Methods A population-based cervical screening program was performed in Chiang Mai (Northern Thailand) using cytology (conventional Pap test) and HPV test (Hybrid Capture 2). Women who had abnormal cytology or were HPV-positive were referred for colposcopy. Cervical samples from these women were genotyped using the Linear Array assay. Results Of 5,456 women, 2.0% had abnormal Pap test results and 6.5% tested positive with Hybrid Capture 2. Of 5,433 women eligible for analysis, 355 with any positive test had histologic confirmation and 57 of these had histologic HSIL+. The sensitivity for histologic HSIL+ detection was 64.9% for Pap test and 100% for Hybrid Capture 2, but the ratio of colposcopy per detection of each HSIL+ was more than two-fold higher with Hybrid Capture 2 than Pap test (5.9 versus 2.8). Genotyping results were available in 316 samples. HPV52, HPV16, and HPV58 were the three most common genotypes among women with histologic HSIL+. Performance of genotyping triage using HPV16/18/52/58 was superior to that of HPV16/18, with a higher sensitivity (85.7% versus 28.6%) and negative predictive value (94.2% versus 83.9%). Conclusions In Northern Thailand, HPV testing with genotyping triage shows better screening performance than cervical cytology alone. In this region, the addition of genotyping for HPV52/58 to HPV16/18 is deemed necessary in triaging women with positive HPV test. PMID:27336913

Risk factor assessment to anticipate performance in the National Developmental Screening Test in children from a disadvantaged area.

PubMed

Montes, Alejandro; Pazos, Gustavo

2016-02-01

Identifying children at risk of failing the National Developmental Screening Test by combining prevalences of children suspected of having inapparent developmental disorders (IDDs) and associated risk factors (RFs) would allow to save resources. 1. To estimate the prevalence of children suspected of having IDDs. 2. To identify associated RFs. 3. To assess three methods developed based on observed RFs and propose a pre-screening procedure. The National Developmental Screening Test was administered to 60 randomly selected children aged between 2 and 4 years old from a socioeconomically disadvantaged area from Puerto Madryn. Twenty-four biological and socioenvironmental outcome measures were assessed in order to identify potential RFs using bivariate and multivariate analyses. The likelihood of failing the screening test was estimated as follows: 1. a multivariate logistic regression model was developed; 2. a relationship was established between the number of RFs present in each child and the percentage of children who failed the test; 3. these two methods were combined. The prevalence of children suspected of having IDDs was 55.0% (95% confidence interval: 42.4%-67.6%). Six RFs were initially identified using the bivariate approach. Three of them (maternal education, number of health checkups and Z scores for height-for-age, and maternal age) were included in the logistic regression model, which has a greater explanatory power. The third method included in the assessment showed greater sensitivity and specificity (85% and 79%, respectively). The estimated prevalence of children suspected of having IDDs was four times higher than the national standards. Seven RFs were identified. Combining the analysis of risk factor accumulation and a multivariate model provides a firm basis for developing a sensitive, specific and practical pre-screening procedure for socioeconomically disadvantaged areas. Sociedad Argentina de Pediatría.

Silver-Teflon coating improvement

NASA Technical Reports Server (NTRS)

Reed, M. W.

1976-01-01

Approximately forty adhesives were subjected to laboratory screening. Seven candidate adhesives were selected from the screening tests and evaluated in a thermal vacuum test on radiator panels similar to the anticipated flight hardware configuration. Several classes of adhesives based on epoxide, polyester, silicone, and urethane resin systems were tested. These included contact adhesives, heat cured adhesives, heat and pressure cured adhesives, pressure sensitive adhesives, and two part paint-on or spray-on adhesives. The panels were tested in a space environmental simulation laboratory chamber during the July 9-20, 1973 time span.

"Chair Stand Test" as Simple Tool for Sarcopenia Screening in Elderly Women.

PubMed

Pinheiro, P A; Carneiro, J A O; Coqueiro, R S; Pereira, R; Fernandes, M H

2016-01-01

To investigate the association between sarcopenia and "chair stand test" performance, and evaluate this test as a screening tool for sarcopenia in community-dwelling elderly women. Cross-sectional Survey. 173 female individuals, aged ≥ 60 years and living in the urban area of the municipality of Lafaiete Coutinho, Bahia's inland, Brazil. The association between sarcopenia (defined by muscle mass, strength and/or performance loss) and performance in the "chair stand test" was tested by binary logistic regression technique. The ROC curve parameters were used to evaluate the diagnostic power of the test in sarcopenia screening. The significance level was set at 5 %. The model showed that the time spent for the "chair stand test" was positively associated (OR = 1.08; 95% CI = 1.01 - 1.16, p = 0.024) to sarcopenia, indicating that, for each 1 second increment in the test performance, the sarcopenia's probability increased by 8% in elderly women. The cut-off point that showed the best balance between sensitivity and specificity was 13 seconds. The performance of "chair stand test" showed predictive ability for sarcopenia, being an effective and simple screening tool for sarcopenia in elderly women. This test could be used for screening sarcopenic elderly women, allowing early interventions.

Electrocardiographic screening for emphysema: the frontal plane P axis.

PubMed

Baljepally, R; Spodick, D H

1999-03-01

Because the most characteristic and sensitive electrocardiographic (ECG) correlate of pulmonary emphysema in adults is verticalization of the frontal plane P-wave vector (P axis), we investigated its strength as a lone criterion to screen for obstructive pulmonary disease (OPD) in an adult hospital population. In all, 954 consecutive unselected ECGs were required to yield 100 with P axis > or = +70 degrees (unequivocally negative P in a VL during sinus rhythm) and pulmonary function tests. and 100 with P axis < or = +50 degrees (unequivocally positive P-aVL). Obstructive pulmonary disease by both pulmonary function test and clinical criteria was present in 89 of 100 patients with vertical P axes and 4 of 100 patients without OPD. The high sensitivity (89% for this series) and high specificity (96%) makes vertical P axis a useful screening criterion. Its at-a-glance simplicity makes it "user-friendly."

Automatic classification of transiently evoked otoacoustic emissions using an artificial neural network.

PubMed

Buller, G; Lutman, M E

1998-08-01

The increasing use of transiently evoked otoacoustic emissions (TEOAE) in large neonatal hearing screening programmes makes a standardized method of response classification desirable. Until now methods have been either subjective or based on arbitrary response characteristics. This study takes an expert system approach to standardize the subjective judgements of an experienced scorer. The method that is developed comprises three stages. First, it transforms TEOAEs from waveforms in the time domain into a simplified parameter set. Second, the parameter set is classified by an artificial neural network that has been taught on a large database TEOAE waveforms and corresponding expert scores. Third, additional fuzzy logic rules automatically detect probable artefacts in the waveforms and synchronized spontaneous emission components. In this way, the knowledge of the experienced scorer is encapsulated in the expert system software and thereafter can be accessed by non-experts. Teaching and evaluation of the neural network was based on TEOAEs from a database totalling 2190 neonatal hearing screening tests. The database was divided into learning and test groups with 820 and 1370 waveforms respectively. From each recorded waveform a set of 12 parameters was calculated, representing signal static and dynamic properties. The artifical network was taught with parameter sets of only the learning groups. Reproduction of the human scorer classification by the neural net in the learning group showed a sensitivity for detecting screen fails of 99.3% (299 from 301 failed results on subjective scoring) and a specificity for detecting screen passes of 81.1% (421 of 519 pass results). To quantify the post hoc performance of the net (generalization), the test group was then presented to the network input. Sensitivity was 99.4% (474 from 477) and specificity was 87.3% (780 from 893). To check the efficiency of the classification method, a second learning group was selected out of the previous test group, and the previous learning group was used as the test group. Repeating learning and test procedures yielded 99.3% sensitivity and 80.7% specificity for reproduction, and 99.4% sensitivity and 86.7% specificity for generalization. In all respects, performance was better than for a previously optimized method based simply on cross-correlation between replicate non-linear waveforms. It is concluded that classification methods based on neural networks show promise for application to large neonatal screening programmes utilizing TEOAEs.

Screen or not to screen for peripheral arterial disease: guidance from a decision model.

PubMed

Vaidya, Anil; Joore, Manuela A; Ten Cate-Hoek, Arina J; Ten Cate, Hugo; Severens, Johan L

2014-01-29

Asymptomatic Peripheral Arterial Disease (PAD) is associated with greater risk of acute cardiovascular events. This study aims to determine the cost-effectiveness of one time only PAD screening using Ankle Brachial Index (ABI) test and subsequent anti platelet preventive treatment (low dose aspirin or clopidogrel) in individuals at high risk for acute cardiovascular events compared to no screening and no treatment using decision analytic modelling. A probabilistic Markov model was developed to evaluate the life time cost-effectiveness of the strategy of selective PAD screening and consequent preventive treatment compared to no screening and no preventive treatment. The analysis was conducted from the Dutch societal perspective and to address decision uncertainty, probabilistic sensitivity analysis was performed. Results were based on average values of 1000 Monte Carlo simulations and using discount rates of 1.5% and 4% for effects and costs respectively. One way sensitivity analyses were performed to identify the two most influential model parameters affecting model outputs. Then, a two way sensitivity analysis was conducted for combinations of values tested for these two most influential parameters. For the PAD screening strategy, life years and quality adjusted life years gained were 21.79 and 15.66 respectively at a lifetime cost of 26,548 Euros. Compared to no screening and treatment (20.69 life years, 15.58 Quality Adjusted Life Years, 28,052 Euros), these results indicate that PAD screening and treatment is a dominant strategy. The cost effectiveness acceptability curves show 88% probability of PAD screening being cost effective at the Willingness To Pay (WTP) threshold of 40000 Euros. In a scenario analysis using clopidogrel as an alternative anti-platelet drug, PAD screening strategy remained dominant. This decision analysis suggests that targeted ABI screening and consequent secondary prevention of cardiovascular events using low dose aspirin or clopidogrel in the identified patients is a cost-effective strategy. Implementation of targeted PAD screening and subsequent treatment in primary care practices and in public health programs is likely to improve the societal health and to save health care costs by reducing catastrophic cardiovascular events.

Cost-Effectiveness of Screening for Intermediate Age-Related Macular Degeneration during Diabetic Retinopathy Screening.

PubMed

Chan, Christina K W; Gangwani, Rita A; McGhee, Sarah M; Lian, JinXiao; Wong, David S H

2015-11-01

To determine whether screening for age-related macular degeneration (AMD) during a diabetic retinopathy (DR) screening program would be cost effective in Hong Kong. We compared and evaluated the impacts of screening, grading, and vitamin treatment for intermediate AMD compared with no screening using a Markov model. It was based on the natural history of AMD in a cohort with a mean age of 62 years, followed up until 100 years of age or death. Subjects attending a DR screening program were recruited. A cost-effectiveness analysis was undertaken from a public provider perspective. It included grading for AMD using the photographs obtained for DR screening and treatment with vitamin therapy for those with intermediate AMD. The measures of effectiveness were obtained largely from a local study, but the transition probabilities and utility values were from overseas data. Costs were all from local sources. The main assumptions and estimates were tested in sensitivity analyses. The outcome was cost per quality-adjusted life year (QALY) gained. Both costs and benefits were discounted at 3%. All costs are reported in United States dollars ($). The cost per QALY gained through screening for AMD and vitamin treatment for appropriate cases was $12,712 after discounting. This would be considered highly cost effective based on the World Health Organization's threshold of willingness to pay (WTP) for a QALY, that is, less than the annual per capita gross domestic product of $29,889. Because of uncertainty regarding the utility value for those with advanced AMD, we also tested an extreme, conservative value for utility under which screening remained cost effective. One-way sensitivity analyses revealed that, besides utility values, the cost per QALY was most sensitive to the progression rate from intermediate to advanced AMD. The cost-effectiveness acceptability curve showed a WTP for a QALY of $29,000 or more has a more than 86% probability of being cost effective compared with no screening. Our analysis demonstrated that AMD screening carried out simultaneously with DR screening for patients with diabetes would be cost effective in a Hong Kong public healthcare setting. Copyright © 2015 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.

Validity of Forced Eyelid Closure Test: A Novel Clinical Screening Test for Ocular Myasthenia Gravis.

PubMed

Apinyawasisuk, Supanut; Zhou, Xinkai; Tian, Jack J; Garcia, Giancarlo A; Karanjia, Rustum; Sadun, Alfredo A

2017-09-01

Forced eyelid closure test (FECT) is a clinical screening test developed from the original Cogan lid twitch (CLT) sign to assist in the diagnosis of ocular myasthenia gravis (OMG), We evaluated the sensitivity and specificity of FECT compared with CLT and benchmarked to standard diagnostic tests. This study was a retrospective chart review of 48 patients using electronic medical records of those that presented with ptosis and/or diplopia at Doheny Eye Institute, University of California, Los Angeles between February 2015 and April 2016. Patients without FECT testing were excluded. FECT and CLT results, and final diagnosis were recorded. To perform FECT, the patient was asked to squeeze his or her eyelids shut for 5-10 seconds then open quickly and fixate in primary position. The excessive upward overshoot of eyelids movement indicated a positive FECT. The test was performed by a neuro-ophthalmologist before establishing the diagnosis. Patients who had equivocal test results and/or inconclusive final diagnosis were excluded. Of the 48 patients studied, 18 patients (37.5%) had positive FECT; 15 of whom had a final diagnosis of OMG (83.3%). Of the 30 patients with negative FECT, 1 had OMG (3.3%). Of the 48 patients, 35 patients also had a documented CLT result (72.9%). CLT was positive in 11 of these 35 patients (31.4%), and 9 of these 11 had OMG (81.8%). Of the 24 patients with negative CLT, 2 of them had OMG (8.3%). Sensitivity and specificity of FECT were 94% and 91% (joint 95% confidence region: sensitivity × specificity = [0.70, 1] × [0.75, 1]). The relative true-positive fraction (rTPF) between FECT and CLT was 1.15; the relative false-positive fraction was 1.31. FECT is a simple clinical screening test with good sensitivity and specificity for OMG.

Screening for skin cancer.

PubMed

Helfand, M; Mahon, S M; Eden, K B; Frame, P S; Orleans, C T

2001-04-01

Malignant melanoma is often lethal, and its incidence in the United States has increased rapidly over the past 2 decades. Nonmelanoma skin cancer is seldom lethal, but, if advanced, can cause severe disfigurement and morbidity. Early detection and treatment of melanoma might reduce mortality, while early detection and treatment of nonmelanoma skin cancer might prevent major disfigurement and to a lesser extent prevent mortality. Current recommendations from professional societies regarding screening for skin cancer vary. To examine published data on the effectiveness of routine screening for skin cancer by a primary care provider, as part of an assessment for the U.S. Preventive Services Task Force. We searched the MEDLINE database for papers published between 1994 and June 1999, using search terms for screening, physical examination, morbidity, and skin neoplasms. For information on accuracy of screening tests, we used the search terms sensitivity and specificity. We identified the most important studies from before 1994 from the Guide to Clinical Preventive Services, second edition, and from high-quality reviews. We used reference lists and expert recommendations to locate additional articles. Two reviewers independently reviewed a subset of 500 abstracts. Once consistency was established, the remainder were reviewed by one reviewer. We included studies if they contained data on yield of screening, screening tests, risk factors, risk assessment, effectiveness of early detection, or cost effectiveness. We abstracted the following descriptive information from full-text published studies of screening and recorded it in an electronic database: type of screening study, study design, setting, population, patient recruitment, screening test description, examiner, advertising targeted at high-risk groups or not targeted, reported risk factors of participants, and procedure for referrals. We also abstracted the yield of screening data including probabilities and numbers of referrals, types of suspected skin cancers, biopsies, confirmed skin cancers, and stages and thickness of skin cancers. For studies that reported test performance, we recorded the definition of a suspicious lesion, the "gold-standard" determination of disease, and the number of true positive, false positive, true negative, and false negative test results. When possible, positive predictive values, likelihood ratios, sensitivity, and specificity were recorded. No randomized or case-control studies have been done that demonstrate that routine screening for melanoma by primary care providers reduces morbidity or mortality. Basal cell carcinoma and squamous cell carcinoma are very common, but detection and treatment in the absence of formal screening are almost always curative. No controlled studies have shown that formal screening programs will improve this already high cure rate. While the efficacy of screening has not been established, the screening procedures themselves are noninvasive, and the follow-up test, skin biopsy, has low morbidity. Five studies from mass screening programs reported the accuracy of skin examination as a screening test. One of these, a prospective study, tracked patients with negative results to determine the number of patients with false-negative results. In this study, the sensitivity of screening for skin cancer was 94% and specificity was 98%. Several recent case-control studies confirm earlier evidence that risk of melanoma rises with the presence of atypical moles and/or many common moles. One well-done prospective study demonstrated that risk assessment by limited physical exam identified a relatively small (<10%) group of primary care patients for more thorough evaluation. The quality of the evidence addressing the accuracy of routine screening by primary care providers for early detection of melanoma or nonmelanoma skin cancer ranged from poor to fair. We found no studies that assessed the effectiveness of periodic skin examination by a clinician in reducing melanoma mortality. Both self-assessment of risk factors or clinician examination can classify a small proportion of patients as at highest risk for melanoma. Skin cancer screening, perhaps using a risk-assessment technique to identify high-risk patients who are seeing a physician for other reasons, merits additional study as a strategy to address the excess burden of disease in older adults.

The cost of implementation of the Clinical Laboratory Improvement Amendments of 1988--the example of pediatric office-based cholesterol screening.

PubMed

Tershakovec, A M; Brannon, S D; Bennett, M J; Shannon, B M

1995-08-01

To measure the additional costs of office-based laboratory testing due to the implementation of the Clinical Laboratory Improvement Amendments of 1988 (CLIA '88), using cholesterol screening for children as an example. Four- to ten-year-old children who received their well child care at one of seven participating pediatric practices were screened for hypercholesterolemia. The average number of analyses per day and days per month were derived from the volume of testing completed by the practices. Nurses and technicians time in the screening process were measured and personnel costs were calculated based on salary and fringe benefit rates. Costs of supplies, analyzing control samples, instrument calibration, and instrument depreciation were included. Costs estimates of screening were then completed. CLIA '88 implementation costs were derived from appropriate proficiency testing and laboratory inspection programs. In six practices completing a low volume of testing, 2807 children (5 to 6 children per week) were screened during the observation period, while 414 (about 25 children per week) were screened in one high-volume practice implementing universal screening over a 4-month period. For the six low-volume practices, the cost of screening was $10.60 per child. This decreased to $5.47 for the high-volume practice. Estimated costs of CLIA '88 implementation, including additional proficiency testing and laboratory inspection, added $3.20 per test for the low-volume practices, and $0.71 per test for the high-volume testing. Implementation of CLIA adds significantly to the cost of office-based chemistry laboratory screening. Despite these additional expenses, the cost of testing is still within a reasonable charge for laboratory testing, and is highly sensitive to the volume of tests completed.

Technologic advances for evaluation of cervical cytology: is newer better?

PubMed

Hartmann, K E; Nanda, K; Hall, S; Myers, E

2001-12-01

Among those women who have cervical cancer and have been screened, 14% to 33% of the cases represent failure to detect abnormalities that existed at the time of screening. New technologies intended to improve detection of cytologic abnormalities include liquid-based, thin-layer cytology (ThinPrep, AutoCyte), computerized rescreening (PAPNET), and algorithm-based computer rescreening (AutoPap). This report combines evidence reviews conducted for the U.S. Preventive Services Task Force and the Agency for Healthcare Research and Quality, in which we systematically identified articles on cervical neoplasia, cervical dysplasia, and screening published between January 1966 and March 2001. We note the challenges for improving screening methods, providing an overview of methods for collecting and evaluating cytologic samples, and examining the evidence about the diagnostic performance of new technologies for detecting cervical lesions. Using standard criteria for evaluation of the diagnostic tests, we determined that knowledge about the sensitivity, specificity, and predictive values of new technologies is meager. Only one study of liquid-based cytology used a reference standard of colposcopy, with histology as indicated, to assess participants with normal screening results. Lack of an adequate reference standard is the overwhelming reason that test characteristics cannot be properly assessed or compared. Most publications compare results of screening using the new technology with expert panel review of the cytologic specimen. In that case, the tests are not independent measures and do nothing to relate the screening test findings to the true status of the cervix, making determination of false-negatives, and thus sensitivity, specificity, and negative predictive value, impossible. We did not identify any literature about health outcomes or cost effectiveness of using these tools in a system of screening. For the purposes of guiding decision making about choice of screening tools, the current evidence is inadequate to gauge whether new technologies are "better" than conventional cytology..

A systematic review of screening questionnaires for childhood lead poisoning.

PubMed

Ossiander, Eric M

2013-01-01

The Centers for Disease Control and Prevention encourages the use of risk factor questionnaires to screen children for lead poisoning. A majority of state health departments have formal lead screening guidelines that recommend health care providers use questionnaires. We conducted a systematic review to evaluate the ability of lead screening questionnaires to predict lead poisoning risk among children. Articles that reported the evaluation of a predesigned lead screening questionnaire were obtained by searching Medline/PubMed and by examining references of articles obtained through the online search. From each evaluation, we abstracted the number of children that were true positive, false positive, true negative, and false negative, according to the results of the screening questionnaire and the follow-up blood lead test. From these data, we calculated specificity and sensitivity of the questionnaire for each evaluation. Twenty articles met the inclusion criteria: these included 28 separate questionnaire evaluations. Among 17 evaluations of the 1991 Centers for Disease Control and Prevention questionnaire, sensitivity ranged from 0.25 to 0.87, specificity from 0.31 to 0.80, and accuracy (sum of sensitivity and specificity) from 0.74 to 1.39. The pooled mean estimates for this questionnaire were sensitivity 0.61 (95% confidence interval: 0.53-0.68); specificity 0.52 (0.45-0.60); accuracy 1.12 (1.06-1.18). Among 11 evaluations of all other questionnaires, sensitivity ranged from 0.43 to 0.90, specificity from 0.17 to 0.66, and accuracy from 0.94 to 1.27. For these questionnaires, the pooled mean estimates were sensitivity 0.76 (0.68-0.85), specificity 0.41 (0.33-0.49), and accuracy 1.12 (1.06-1.18). Lead screening questionnaires showed a wide range of sensitivity and specificity and performed little better than chance at predicting lead poisoning risk among children.

The Significance of Sensitive Interferon Gamma Release Assays for Diagnosis of Latent Tuberculosis Infection in Patients Receiving Tumor Necrosis Factor-α Antagonist Therapy.

PubMed

Jung, Yu Jung; Woo, Hye In; Jeon, Kyeongman; Koh, Won-Jung; Jang, Dong Kyoung; Cha, Hoon Suk; Koh, Eun Mi; Lee, Nam Yong; Kang, Eun-Suk

2015-01-01

We compared two interferon gamma release assays (IGRAs), QuantiFERON-TB Gold In-Tube (QFT-GIT) and T-SPOT.TB, for diagnosis of latent tuberculosis infection (LTBI) in patients before and while receiving tumor necrosis factor (TNF)-α antagonist therapy. This study evaluated the significance of sensitive IGRAs for LTBI screening and monitoring. Before starting TNF-α antagonist therapy, 156 consecutive patients with rheumatic diseases were screened for LTBI using QFT-GIT and T-SPOT.TB tests. According to our study protocol, QFT-GIT-positive patients received LTBI treatment. Patients positive by any IGRAs were subjected to follow-up IGRA tests after completing LTBI-treatment and/or during TNF-α antagonist therapy. At the initial LTBI screening, 45 (28.9%) and 70 (44.9%) patients were positive by QFT-GIT and T-SPOT.TB, respectively. The agreement rate between IGRA results was 78.8% (k = 0.56; 95% confidence interval [95% CI] = 0.43 to 0.68). Of 29 patients who were positive only by T-SPOT.TB in the initial screening, 83% (19/23) were persistently positive by T-SPOT.TB, while QFT-GIT testing showed that 36% (9/25) had conversion during TNF-α antagonist therapy. By the end of the follow-up period (218 to 1,264 days), four patients (4/137, 2.9%) developed active tuberculosis (TB) diseases during receiving TNF-α antagonist therapy. Among them, one was Q-T+, one was Q+T-, and the remaining two were Q-T- at the initial screening (Q, QuantiFERON-TB Gold In-Tube; T, T-SPOT.TB; +, positive; -, negative). Two (2/4, 50%) patients with TB reactivation had at least one prior risk factor consistent with previous TB infection. This study demonstrated the need to capitalize on sensitive IGRAs to monitor for LTBI in at-risk patients for a more sensitive diagnosis in countries with an intermediate TB burden.

Concurrent evaluation of visual, cytological and HPV testing as screening methods for the early detection of cervical neoplasia in Mumbai, India.

PubMed

Shastri, Surendra S; Dinshaw, Ketayun; Amin, Geetanjali; Goswami, Smriti; Patil, Sharmila; Chinoy, Roshini; Kane, S; Kelkar, Rohini; Muwonge, Richard; Mahé, Cédric; Ajit, Dulhan; Sankaranarayanan, R

2005-03-01

Naked eye visual inspection with acetic acid (VIA), magnified VIA (VIAM), visual inspection with Lugol's iodine (VILI), cytology and human papillomavirus (HPV) testing were evaluated as screening methods for the detection of high-grade squamous intraepithelial lesions (HSIL) of the uterine cervix in a cross-sectional study in Mumbai, India. Cytology, HPV testing, VIA, VIAM and VILI were carried out concurrently for 4039 women aged 30-65 years. All women were investigated with colposcopy and biopsies were taken from 939 women who had colposcopic abnormalities. The reference standard for final disease status was histology or negative colposcopy. The presence of HSIL was confirmed in 57 women (1.4%). The test characteristics for each method were calculated using standard formulae. The sensitivities of cytology, HPV testing, VIA, VIAM and VILI were 57.4%, 62.0%, 59.7%, 64.9%, and 75.4%, respectively (differences were not statistically significant). The specificities were 98.6%, 93.5%, 88.4%, 86.3%, and 84.3%, respectively. Adding a visual test to cytology or HPV testing in parallel combination resulted in a substantial increase in sensitivity, with a moderate decrease in specificity. The parallel combination of VILI and HPV testing resulted in a sensitivity of 92.0% and a specificity of 79.9%. As a single test, cytology had the best balance of sensitivity and specificity. Visual tests are promising in low-resource settings, such as India. The use of both VIA and VILI may be considered where good quality cytology or HPV testing are not feasible. The sensitivity of cytology and HPV testing increased significantly when combined with VIA or VILI.

Improving strategies for syphilis control in China: selective testing of sexually transmitted disease patients--too little, too late?

PubMed

Yin, Y-P; Wong, S P Y; Liu, M-S; Wei, W-H; Yu, Y-H; Gao, X; Chen, Q; Fu, Z-Z; Cheng, F; Chen, X-S; Cohen, M S

2008-12-01

Syphilis testing guidelines in China are usually based on symptomatic criteria, overlooking risk assessment and ultimately opportunities for disease detection and control. We used data from 10,695 sexually transmitted disease (STD) clinic patients in Guangxi, China, to assess the efficacy of a potential screening tool inquiring about behavioural and health risk factors in identifying the STD patients who should not be triaged for syphilis testing under current guidelines, but on the contrary receive such testing. Validity testing of the screening tool was performed and receiver-operating characteristic curves were plotted to determine an optimal total risk score cut-off for testing. About 40.9% of patients with positive toluidine red unheated serum test and Treponema pallidum particle agglutination test did not show hallmark signs of syphilis. The screening tool was more sensitive in detecting infection in non-triaged male versus female patients (highest sensitivity = 90% vs. 55%) and the cut-off score to warrant testing was lower in non-triaged female patients than in non-triaged male patients (cut-off = 1 vs. 2). Most of the cases were missed among female STD patients. In spite of selective testing based on behavioural and health indicators that improve case detection, cases were still missed. Our study supports universal testing for syphilis in the STD population.

Evaluation of the Addenbrooke's Cognitive Examination's validity in a brain injury rehabilitation setting.

PubMed

Gaber, Tarek A-Z K

2008-07-01

Several reports have warned of the Mini Mental State Examination's (MMSE) inability to detect gross memory and high executive impairments. Addenbrooke's Cognitive Examination-Revised (ACE-R) has gained enormous popularity in dementia screening as it addresses the main shortcomings of MMSE. This study aimed at evaluating the use of ACE-R and to establish its sensitivity compared to MMSE in a cohort of brain injury patients. ACE-R was administered to a cohort of chronic brain injury patients. All patients had a cognitive impairment which was severe enough to prevent them working or studying. Patients with significant mental health, sensory, communication or physical impairments were excluded. Thirty-six patients were recruited, 31 males with a mean age of 37 years. For an upper cut-off value of 27/30 for MMSE and 88/100 for ACE-R, their sensitivities were 36% and 72%, respectively. For a lower cut-off value of 24/30 and 82/100 the tests sensitivities were 11% and 56%, respectively. Analysis of the ACE-R sub-tests indicated that memory and verbal fluency sub-tests showed the most dramatic impairment. MMSE is insensitive as a screening test in brain injury patients. The results show ACE-R to be a sensitive, easily administered test.

Age-specific performance of careHPV versus Papanicolaou and visual inspection of cervix with acetic acid testing in a primary cervical cancer screening.

PubMed

Labani, Satyanarayana; Asthana, Smita

2016-01-01

Human papillomavirus (HPV) is recommended as a primary screening tool for cervical screening. Assessment of age-specific performance of newer HPV careHPV DNA testing is important as risk of cervical intraepithelial neoplasia (CIN) varies at different ages. We aim to evaluate careHPV in comparison to Papanicolaou (Pap) test and visual inspection of the cervix with acetic acid (VIA) cervical screening tests for the detection of high-grade CIN. The cross sectional study was conducted in a rural population of North India. Ever-married women 30-59 years of age were invited for screening by careHPV (self-collected vaginal and physician-collected cervical samples), Pap test and VIA. Associations for trend in age for detecting histological-confirmed CINII+ and CINIII+ for each screening test were evaluated. Age-specific association with each screening test was evaluated. Of a total of 7761 women invited, 5032 were screened and analysis was performed on 4658 with all screen test results. No significant (p>0.05) association of age for any screening test in the detection of CINII+ or CINIII+ was observed. For the older age group, cervical HPV (CHPV) showed high sensitivity and specificity for CINII+ detection. Specificity of CHPV or vaginal HPV (VHPV) was equal or higher than Pap in all age groups. Cervical screening options of CHPV or VHPV, or Pap, performed equally in the younger age group while CHPV might be an option for all ages in the detection of high-grade CIN. 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/

Use of Ancillary Carbapenemase Tests To Improve Specificity of Phenotypic Definitions for Carbapenemase-Producing Enterobacteriaceae.

PubMed

Miller, Shelley A; Hindler, Janet A; Chengcuenca, Angelo; Humphries, Romney M

2017-06-01

Carbapenemase-producing Enterobacteriaceae (CPE) are a significant threat to public health. In 2015, CDC revised the surveillance definition for CPE to include all Enterobacteriaceae resistant to any carbapenem tested. However, this definition is associated with poor specificity. We evaluated the performance of this definition, compared to carbapenemase PCR, for a collection of 125 Enterobacteriaceae We also investigated the impact of ancillary testing for carbapenemase of isolates that met the CDC CPE surveillance definition. The two ancillary tests evaluated were the Xpert Carba-R assay, a molecular test, and the carbapenem inactivation method (CIM). Two variables were evaluated for the CIM: suspension of organisms in double-distilled water (ddH 2 O) versus tryptic soy broth (TSB) to incubate disks, and incubation of plates for 6 h versus 18 to 20 h. The sensitivity and specificity of the Carba-R assay were 100% compared to the results of in-house PCR. The sensitivities of the CIM performed with TSB were 94.6% when read at 6 h and 97.7% when read at 18 to 20 h; the sensitivities with ddH 2 O were 88.0% when read at 6 h and 93.0% when incubated for 18 to 20 h. The specificity was 100% for all variables tested. Without ancillary testing, the sensitivity of the CDC definition was 98.9% for CPE, and the specificity was 6.1%. Testing isolates that screened positive by the CDC definition with the Xpert Carba-R did not change the sensitivity, and it improved the specificity to 100%. Similarly, the use of the CIM (TSB and 18 to 20 h of incubation) to confirm screen-positive isolates resulted in a sensitivity of 95.6% and specificity of 100%. Copyright © 2017 American Society for Microbiology.

Validation of the Arab Youth Mental Health scale as a screening tool for depression/anxiety in Lebanese children

PubMed Central

2011-01-01

Background Early detection of common mental disorders, such as depression and anxiety, among children and adolescents requires the use of validated, culturally sensitive, and developmentally appropriate screening instruments. The Arab region has a high proportion of youth, yet Arabic-language screening instruments for mental disorders among this age group are virtually absent. Methods We carried out construct and clinical validation on the recently-developed Arab Youth Mental Health (AYMH) scale as a screening tool for depression/anxiety. The scale was administered with 10-14 year old children attending a social service center in Beirut, Lebanon (N = 153). The clinical assessment was conducted by a child and adolescent clinical psychiatrist employing the DSM IV criteria. We tested the scale's sensitivity, specificity, and internal consistency. Results Scale scores were generally significantly associated with how participants responded to standard questions on health, mental health, and happiness, indicating good construct validity. The results revealed that the scale exhibited good internal consistency (Cronbach's alpha = 0.86) and specificity (79%). However, it exhibited moderate sensitivity for girls (71%) and poor sensitivity for boys (50%). Conclusions The AYMH scale is useful as a screening tool for general mental health states and a valid screening instrument for common mental disorders among girls. It is not a valid instrument for detecting depression and anxiety among boys in an Arab culture. PMID:21435213

Cross-validation of a dementia screening test in a heterogeneous population.

PubMed

Ritchie, K A; Hallerman, E F

1989-09-01

Recognition of the increasing importance of early dementia screening for both research and clinical purposes has led to the development of numerous screening instruments. The most promising of these are based on neuropsychological measures which are able to focus on very specific cognitive functions. Of these tests the Iowa screening test is of particular interest to researchers and clinicians working with heterogenous populations or wishing to make cross-cultural comparisons as it is relatively culture-fair and does not assume literacy. A preliminary study of the performance of the Iowa in an Israeli sample of diverse ethnic origins and low education level suggests it to be a very sensitive measure even in such groups. The study also demonstrates the inadvisability of adopting item weights derived by multivariate statistical techniques from another population.

Prevalence of beryllium sensitization among Department of Defense conventional munitions workers at low risk for exposure.

PubMed

Mikulski, Marek A; Sanderson, Wayne T; Leonard, Stephanie A; Lourens, Spencer; Field, R William; Sprince, Nancy L; Fuortes, Laurence J

2011-03-01

To estimate the prevalence of beryllium sensitization among former and current Department of Defense workers from a conventional munitions facility. Participants were screened by using Beryllium Lymphocyte Proliferation Test. Those sensitized were offered clinical evaluation for chronic beryllium disease. Eight (1.5%) of 524 screened workers were found sensitized to beryllium. Although the confidence interval was wide, the results suggested a possibly higher risk of sensitization among workers exposed to beryllium by occasional resurfacing of copper-2% beryllium alloy tools compared with workers with the lowest potential exposure (odds ratio = 2.6; 95% confidence interval, 0.23-29.9). The findings from this study suggest that Department of Defense workers with low overall exposure to beryllium had a low prevalence of beryllium sensitization. Sensitization rates might be higher where higher beryllium exposures presumably occurred, although this study lacked sufficient power to confirm this.

Sample-to-answer palm-sized nucleic acid testing device towards low-cost malaria mass screening.

PubMed

Choi, Gihoon; Prince, Theodore; Miao, Jun; Cui, Liwang; Guan, Weihua

2018-05-19

The effectiveness of malaria screening and treatment highly depends on the low-cost access to the highly sensitive and specific malaria test. We report a real-time fluorescence nucleic acid testing device for malaria field detection with automated and scalable sample preparation capability. The device consists a compact analyzer and a disposable microfluidic reagent compact disc. The parasite DNA sample preparation and subsequent real-time LAMP detection were seamlessly integrated on a single microfluidic compact disc, driven by energy efficient non-centrifuge based magnetic field interactions. Each disc contains four parallel testing units which could be configured either as four identical tests or as four species-specific tests. When configured as species-specific tests, it could identify two of the most life-threatening malaria species (P. falciparum and P. vivax). The NAT device is capable of processing four samples simultaneously within 50 min turnaround time. It achieves a detection limit of ~0.5 parasites/µl for whole blood, sufficient for detecting asymptomatic parasite carriers. The combination of the sensitivity, specificity, cost, and scalable sample preparation suggests the real-time fluorescence LAMP device could be particularly useful for malaria screening in the field settings. Copyright © 2018 Elsevier B.V. All rights reserved.

Brief screening questionnaires to identify problem drinking during pregnancy: a systematic review.

PubMed

Burns, Ethel; Gray, Ron; Smith, Lesley A

2010-04-01

Although prenatal screening for problem drinking during pregnancy has been recommended, guidance on screening instruments is lacking. We investigated the sensitivity, specificity and predictive value of brief alcohol screening questionnaires to identify problem drinking in pregnant women. Electronic databases from their inception to June 2008 were searched, as well as reference lists of eligible papers and related review papers. We sought cohort or cross-sectional studies that compared one or more brief alcohol screening questionnaire(s) with reference criteria obtained using structured interviews to detect 'at-risk' drinking, alcohol abuse or dependency in pregnant women receiving prenatal care. Five studies (6724 participants) were included. In total, seven instruments were evaluated: TWEAK (Tolerance, Worried, Eye-opener, Amnesia, Kut down), T-ACE [Take (number of drinks), Annoyed, Cut down, Eye-opener], CAGE (Cut down, Annoyed, Guilt, Eye-opener], NET (Normal drinker, Eye-opener, Tolerance), AUDIT (Alcohol Use Disorder Identification Test), AUDIT-C (AUDIT-consumption) and SMAST (Short Michigan Alcohol Screening Test). Study quality was generally good, but lack of blinding was a common weakness. For risk drinking sensitivity was highest for T-ACE (69-88%), TWEAK (71-91%) and AUDIT-C (95%), with high specificity (71-89%, 73-83% and 85%, respectively). CAGE and SMAST performed poorly. Sensitivity of AUDIT-C at score >or=3 was high for past year alcohol dependence (100%) or alcohol use disorder (96%) with moderate specificity (71% each). For life-time alcohol dependency the AUDIT at score >or=8 performed poorly. T-ACE, TWEAK and AUDIT-C show promise for screening for risk drinking, and AUDIT-C may also be useful for identifying alcohol dependency or abuse. However, their performance as stand-alone tools is uncertain, and further evaluation of questionnaires for prenatal alcohol use is warranted.

[Possibilities of the TruScreen for screening of precancer and cancer of the uterine cervix].

PubMed

Zlatkov, V

2009-01-01

The classic approach of detection of pre-cancer and cancer of uterine cervix includes cytological examination, followed by colposcopy assessment of the detected cytological abnormalities. Real-time devices use in-vivo techniques for the measurement, computerized analysis and classifying of different types of cervical tissues. The aim of the present review is to present the technical characteristics and to discus the diagnostic possibilities of TruScreen-automated optical-electron system for cervical screening. The analysis of the presented in the literature diagnostic value of the method at different grades intraepithelial lesions shows that it has higher sensitivity (67-70%) and lower specificity (81%) in comparison to the Pap test with the following results (45-69% sensitivity and 95% specificity). This makes the method suitable for independent primary screening, as well as for adding the diagnostic assurance of the cytological method.

Mass spectrometric-based stable isotopic 2-aminobenzoic acid glycan mapping for rapid glycan screening of biotherapeutics.

PubMed

Prien, Justin M; Prater, Bradley D; Qin, Qiang; Cockrill, Steven L

2010-02-15

Fast, sensitive, robust methods for "high-level" glycan screening are necessary during various stages of a biotherapeutic product's lifecycle, including clone selection, process changes, and quality control for lot release testing. Traditional glycan screening involves chromatographic or electrophoretic separation-based methods, and, although reproducible, these methods can be time-consuming. Even ultrahigh-performance chromatographic and microfluidic integrated LC/MS systems, which work on the tens of minute time scale, become lengthy when hundreds of samples are to be analyzed. Comparatively, a direct infusion mass spectrometry (MS)-based glycan screening method acquires data on a millisecond time scale, exhibits exquisite sensitivity and reproducibility, and is amenable to automated peak annotation. In addition, characterization of glycan species via sequential mass spectrometry can be performed simultaneously. Here, we demonstrate a quantitative high-throughput MS-based mapping approach using stable isotope 2-aminobenzoic acid (2-AA) for rapid "high-level" glycan screening.

A Novel Malaria Pf/Pv Ab Rapid Diagnostic Test Using a Differential Diagnostic Marker Identified by Network Biology.

PubMed

Cho, Sung Jin; Lee, Jihoo; Lee, Hyun Jae; Jo, Hyun-Young; Sinniah, Mangalam; Kim, Hak-Yong; Chong, Chom-Kyu; Song, Hyun-Ok

2016-01-01

Rapid diagnostic tests (RDTs) can detect anti-malaria antibodies in human blood. As they can detect parasite infection at the low parasite density, they are useful in endemic areas where light infection and/or re-infection of parasites are common. Thus, malaria antibody tests can be used for screening bloods in blood banks to prevent transfusion-transmitted malaria (TTM), an emerging problem in malaria endemic areas. However, only a few malaria antibody tests are available in the microwell-based assay format and these are not suitable for field application. A novel malaria antibody (Ab)-based RDT using a differential diagnostic marker for falciparum and vivax malaria was developed as a suitable high-throughput assay that is sensitive and practical for blood screening. The marker, merozoite surface protein 1 (MSP1) was discovered by generation of a Plasmodium-specific network and the hierarchical organization of modularity in the network. Clinical evaluation revealed that the novel Malaria Pf/Pv Ab RDT shows improved sensitivity (98%) and specificity (99.7%) compared with the performance of a commercial kit, SD BioLine Malaria P.f/P.v (95.1% sensitivity and 99.1% specificity). The novel Malaria Pf/Pv Ab RDT has potential for use as a cost-effective blood-screening tool for malaria and in turn, reduces TTM risk in endemic areas.

Postage stamp-sized array sensor for the sensitive screening test of heavy-metal ions.

PubMed

Zhang, Yu; Li, Xiao; Li, Hui; Song, Ming; Feng, Liang; Guan, Yafeng

2014-10-07

The sensitive determination of heavy-metal ions has been widely investigated in recent years due to their threat to the environment and to human health. Among various analytical detection techniques, inexpensive colorimetric testing papers/strips play a very important role. The limitation, however, is also clear: the sensitivity is usually low and the selectivity is poor. In this work, we have developed a postage stamp-sized array sensor composed of nine commercially available heterocyclic azo indicators. Combining filtration-based enrichment with an array of technologies-based pattern-recognition, we have obtained the discrimination capability for seven heavy-metal ions (Hg(2+), Pb(2+), Ag(+), Ni(2+), Cu(2+), Zn(2+), and Co(2+)) at their Chinese wastewater discharge standard concentrations. The allowable detection level of Hg(2+) was down to 0.05 mg L(-1). The heavy-metal ions screening test was readily achieved using a standard chemometric approach. And the array sensor applied well in real water samples.

Reagent strip testing is not sensitive for the screening of asymptomatic bacteriuria in pregnant women.

PubMed

Lumbiganon, Pisake; Chongsomchai, Chompilas; Chumworathayee, Bundit; Thinkhamrop, Jadsada

2002-08-01

The objective of the study was to assess the diagnostic performance of the reagent strip in screening for asymptomatic bacteriuria in pregnant women using urine culture as a gold standard. This study comprised 204 asymptomatic pregnant women who attended their first antenatal care at Srinagarind Hospital, Khon Kaen University from April 1, 1999 to June 30, 1999. Women with symptoms of urinary tract infection, antibiotic treatment within the previous 7 days, pregnancy-induced hypertension, bleeding per vagina and history of urinary tract diseases were excluded. Urine specimens were collected by clean catched midstream urine technique for urinalysis, reagent strip test and urine culture. Diagnostic performance of reagent strip in terms of sensitivity, specificity, positive and negative predictive value was analyzed. Urine reagent strip test had a sensitivity of 13.9 per cent, a specificity of 95.6 per cent, a positive predictive value of 46.1 per cent, a negative predictive value of 80.6 per cent in detecting asymptomatic bacteriuria in pregnant women.

Comparison of Alcohol Use Disorder Screens During College Athlete Pre-Participation Evaluations.

PubMed

Majka, Erek; Graves, Travis; Diaz, Vanessa A; Player, Marty S; Dickerson, Lori M; Gavin, Jennifer K; Wessell, Andrea

2016-05-01

The US Preventive Services Task Force (USPSTF) recommends screening adults for alcohol misuse, a challenge among young adults who may not have regular primary care. The pre-participation evaluation (PPE) provides an opportunity for screening, but traditional screening tools require extra time in an already busy visit. The objective of this study was to compare the 10-item Alcohol Use Disorders Identification Test (AUDIT) with a single-question alcohol misuse screen in a population of college-aged athletes. This cross-sectional study was performed during an athletic PPE clinic at a college in the Southeastern United States among athletes ages 18 years and older. Written AUDIT and single-question screen "How many times in the past year have you had X or more drinks in a day?" (five for men, four for women) asked orally were administered to each participant. Sensitivity, specificity, and positive and negative predictive values for the single-question screen were compared to AUDIT. A total of 225 athletes were screened; 60% were female; 29% screened positive by AUDIT; 59% positive by single-question instrument. Males were more likely to screen positive by both methods. Compared to the AUDIT, the brief single-question screen had 92% sensitivity for alcohol misuse and 55% specificity. The negative predictive value of the single-question screen was 95% compared to AUDIT. A single-question screen for alcohol misuse in college-aged athletes had a high sensitivity and negative predictive value compared to the more extensive AUDIT screen. Ease of administration of this screening tool is ideal for use within the pre-participation physical among college-aged athletes who may not seek regular medical care.

Head-shaking nystagmus predicts greater disability in unilateral peripheral vestibulopathy.

PubMed

Angeli, Simon I; Velandia, Sandra; Snapp, Hillary

2011-01-01

The objective of this study was to determine the association of the bedside test of head-shaking nystagmus (HSN) with patients' self-perceived dizziness handicap as well as this test's sensitivity and specificity in unilateral peripheral vestibular hypofunction. A retrospective case-control study was performed. The study was held at an academic, tertiary referral center. Fifty-three adult patients with unilateral peripheral hypofunction defined by the caloric test of the videonystagmography with documented bedside HSN and who had completed questionnaires of self-perceived dizziness handicap were included. The sensitivity and specificity of the bedside HSN in patients and 10 healthy controls in diagnosing unilateral vestibular hypofunction defined by videonystagmographic caloric testing and by abnormal gain and symmetry of the vestibular-ocular reflex by rotary chair testing were determined. Scores of the screening test of the Dizziness Handicap Index and Functional Level Scale questionnaires were taken. When using the caloric irrigation test as the reference standard for unilateral vestibular hypofunction, the sensitivity, specificity, and positive predictive value of the bedside HSN were 31%, 96%, and 97%, respectively. When comparing with results of rotational chair testing (vestibular-ocular reflex gain and symmetry), the sensitivity of the HSN test increases to 71%. Patients with positive bedside HSN had higher scores (greater self-perceived dizziness handicap) of the Dizziness Handicap Index (P = .049) and higher (worse) scores of the Functional Level Scale (P = .0377) than those with negative bedside HSN (Wilcoxon rank test). Greater perceived handicap was correlated with a positive bedside HSN in patients with unilateral peripheral vestibulopathy. The HSN has sufficient sensitivity to be used as screening test of uncompensated vestibulopathy in this series. However, a negative HSN alone does not rule out the diagnosis of peripheral vestibular dysfunction. Copyright © 2011 Elsevier Inc. All rights reserved.

Primary care validation of a single-question alcohol screening test.

PubMed

Smith, Peter C; Schmidt, Susan M; Allensworth-Davies, Donald; Saitz, Richard

2009-07-01

Unhealthy alcohol use is prevalent but under-diagnosed in primary care settings. To validate, in primary care, a single-item screening test for unhealthy alcohol use recommended by the National Institute on Alcohol Abuse and Alcoholism (NIAAA). Cross-sectional study. Adult English-speaking patients recruited from primary care waiting rooms. Participants were asked the single screening question, “How many times in the past year have you had X or more drinks in a day?”, where X is 5 for men and 4 for women, and a response of 1 or greater [corrected] is considered positive. Unhealthy alcohol use was defined as the presence of an alcohol use disorder, as determined by a standardized diagnostic interview, or risky consumption, as determined using a validated 30-day calendar method. Of 394 eligible primary care patients, 286 (73%) completed the interview. The single-question screen was 81.8% sensitive (95% confidence interval (CI) 72.5% to 88.5%) and 79.3% specific (95% CI 73.1% to 84.4%) for the detection of unhealthy alcohol use. It was slightly more sensitive (87.9%, 95% CI 72.7% to 95.2%) but was less specific (66.8%, 95% CI 60.8% to 72.3%) for the detection of a current alcohol use disorder. Test characteristics were similar to that of a commonly used three-item screen, and were affected very little by subject demographic characteristics. The single screening question recommended by the NIAAA accurately identified unhealthy alcohol use in this sample of primary care patients. These findings support the use of this brief screen in primary care.

Drug Development and Conservation of Biodiversity in West and Central Africa

DTIC Science & Technology

2003-05-01

trichomonads (Trichomonas vaginalis, Tritrichomonas foetus ). In the trypanosome growth screen, 58 WRAIR extracts and 8 AP#2 extracts were tested. Eight WRAIR...extracts were tested vs metronidazole-resistant and -sensitive strains of T. vaginalis and another 31 were studied in a T. foetus screen. Of 58 WRAIR...metronidazole-resistant T. vaginalis; 4 of 31 extracts were similarly active for T. foetus . For trypanosomes, plant genera yielding active extracts included

Cost-effectiveness of Chlamydia antibody tests in subfertile women.

PubMed

Fiddelers, A A A; Land, J A; Voss, G; Kessels, A G H; Severens, J L

2005-02-01

For the evaluation of tubal function, Chlamydia antibody testing (CAT) has been introduced as a screening test. We compared six CAT screening strategies (five CAT tests and one combination of tests), with respect to their cost-effectiveness, by using IVF pregnancy rate as outcome measure. A decision analytic model was developed based on a source population of 1715 subfertile women. The model incorporates hysterosalpingography (HSG), laparoscopy and IVF. To calculate IVF pregnancy rates, costs, effects, cost-effectiveness and incremental costs per effect of the six different CAT screening strategies were determined. pELISA Medac turned out to be the most cost-effective CAT screening strategy (15 075 per IVF pregnancy), followed by MIF Anilabsystems (15 108). A combination of tests (pELISA Medac and MIF Anilabsystems; 15 127) did not improve the cost-effectiveness of the single strategies. Sensitivity analyses showed that the results are robust for changes in the baseline values of the model parameters. Only small differences were found between the screening strategies regarding the cost-effectiveness, although pELISA Medac was the most cost-effective strategy. Before introducing a particular CAT test into clinical practice, one should consider the effects and consequences of the entire screening strategy, instead of only the diagnostic accuracy of the test used.

Diabetes screening in overweight and obese children and adolescents: choosing the right test.

PubMed

Ehehalt, Stefan; Wiegand, Susanna; Körner, Antje; Schweizer, Roland; Liesenkötter, Klaus-Peter; Partsch, Carl-Joachim; Blumenstock, Gunnar; Spielau, Ulrike; Denzer, Christian; Ranke, Michael B; Neu, Andreas; Binder, Gerhard; Wabitsch, Martin; Kiess, Wieland; Reinehr, Thomas

2017-01-01

Type 2 diabetes can occur without any symptoms, and health problems associated with the disease are serious. Screening tests allowing an early diagnosis are desirable. However, optimal screening tests for diabetes in obese youth are discussed controversially. We performed an observational multicenter analysis including 4848 (2668 female) overweight and obese children aged 7 to 17 years without previously known diabetes. Using HbA1c and OGTT as diagnostic criteria, 2.4% (n = 115, 55 female) could be classified as having diabetes. Within this group, 68.7% had HbA1c levels ≥48 mmol/mol (≥6.5%). FPG ≥126 mg/dl (≥7.0 mmol/l) and/or 2-h glucose levels ≥200 mg/dl (≥11.1 mmol/l) were found in 46.1%. Out of the 115 cases fulfilling the OGTT and/or HbA1c criteria for diabetes, diabetes was confirmed in 43.5%. For FPG, the ROC analysis revealed an optimal threshold of 98 mg/dl (5.4 mmol/l) (sensitivity 70%, specificity 88%). For HbA1c, the best cut-off value was 42 mmol/mol (6.0%) (sensitivity 94%, specificity 93%). HbA1c seems to be more reliable than OGTT for diabetes screening in overweight and obese children and adolescents. The optimal HbA1c threshold for identifying patients with diabetes was found to be 42 mmol/mol (6.0%). What is Known: • The prevalence of obesity is increasing and health problems related to type 2 DM can be serious. However, an optimal screening test for diabetes in obese youth seems to be controversial in the literature. What is New: • In our study, the ROC analysis revealed for FPG an optimal threshold of 98 mg/dl (5.4 mmol/l, sensitivity 70%, specificity 88%) and for HbA1c a best cut-off value of 42 mmol/mol (6.0%, sensitivity 94%, specificity 93%) to detect diabetes. Thus, in overweight and obese children and adolescents, HbA1c seems to be a more reliable screening tool than OGTT.

Evaluation of different methods to detect methicillin resistance in Staphylococcus aureus (MRSA).

PubMed

Alipour, Farzad; Ahmadi, Malahat; Javadi, Shahram

2014-01-01

The studies suggest that dogs living with human are potential risk of becoming MRSA carrier and increased risk of infections caused by MRSA. Phenotypic methods to detect methicillin resistance in Staphylococcus aureus (MRSA) are inadequate. The objective of the present study was to determine methicillin resistance in S. aureus by phenotypic susceptibility test (oxacillin disk diffusion, cefoxitin disk diffusion, oxacillin screen agar) and molecular methods (PCR as a gold standard) and the latex agglutination test for the detection of PBP2a and to evaluate the results of these tests for its sensitivity and specificity. A total of 100 swab samples were taken from muzzle site, in more contact with human, of dogs and MRSA were isolated. Oxacillin (1 μg), cefoxitin (30 μg) disk diffusion and oxacillin screen agar method were used. The isolates were also subjected to latex agglutination test for detection of PBP2a and PCR to detect mecA gene. By PCR 37% of isolates show the presence of mecA. Latex agglutination was found to be the most sensitive (97.29%) and cefoxitin disk diffusion to be the most specific (96.82%) tests for detection of MRSA. Our finding showed that combining oxacillin screen agar or cefoxitin disk diffusion with latex agglutination improves sensitivity and specificity to detect methicillin resistance S. aureus (MRSA) isolates. Copyright © 2014 King Saud Bin Abdulaziz University for Health Sciences. Published by Elsevier Ltd. All rights reserved.

Fasting capillary blood glucose: an appropriate measurement in screening for diabetes and pre-diabetes in low-resource rural settings.

PubMed

Zhao, X; Zhao, W; Zhang, H; Li, J; Shu, Y; Li, S; Cai, L; Zhou, J; Li, Y; Hu, R

2013-01-01

To evaluate the efficiency of fasting capillary blood glucose (FCG) measurement as compared with fasting venous plasma glucose (FPG) measurement in screening diabetes and pre-diabetes in low-resource rural settings. In 2010, 993 participants were randomly selected from 9 villages in Yunnan province using cluster sampling method. Samples for FCG and FPG test were obtained after demographics and physical examination. The oral glucose tolerance test was performed in parallel as gold standard for diagnosis. Diagnostic capacities of the FCG measurement in predicting undiagnosed diabetes and pre-diabetes were assessed. The performance of FCG and FPG tests was compared. Fifty-seven individuals with undiagnosed diabetes and 145 subjects with pre-diabetes were detected. The concordance between FCG and FPG levels was high (r = 0.75, p < 0.001). The area under the curve (AUC) for FCG test in predicting diabetes was 0.88 [95% confidence interval (CI) 0.82-0.93] with the optimal cutoff value of 5.65 mmol/l, sensitivity of 84.2%, and specificity of 79.3%. The corresponding values in FPG tests were 0.92 (95% CI 0.88-0.97) (AUC), 6.51 mmol/l (optimal cutoff point), 82.5% (sensitivity) and 98.3% (specificity), respectively. No significant difference was found in the AUC for the two screening strategies. FCG measurement is considered to be a convenient, practicable screening method in low-resource rural communities with acceptable test properties.

Utility of hepatic transaminases in children with concern for abuse.

PubMed

Lindberg, Daniel M; Shapiro, Robert A; Blood, Emily A; Steiner, R Daryl; Berger, Rachel P

2013-02-01

Routine testing of hepatic transaminases, amylase, and lipase has been recommended for all children evaluated for physical abuse, but rates of screening are widely variable, even among abuse specialists, and data for amylase and lipase testing are lacking. A previous study of screening in centers that endorsed routine transaminase screening suggested that using a transaminase threshold of 80 IU/L could improve injury detection. Our objectives were to prospectively validate the test characteristics of the 80-IU/L threshold and to determine the utility of amylase and lipase to detect occult abdominal injury. This was a retrospective secondary analysis of the Examining Siblings To Recognize Abuse research network, a multicenter study in children younger than 10 years old who underwent subspecialty evaluation for physical abuse. We determined rates of identified abdominal injuries and results of transaminase, amylase, and lipase testing. Screening studies were compared by using basic test characteristics (sensitivity, specificity) and the area under the receiver operating characteristic curve. Abdominal injuries were identified in 82 of 2890 subjects (2.8%; 95% confidence interval: 2.3%-3.5%). Hepatic transaminases were obtained in 1538 (53%) subjects. Hepatic transaminases had an area under the receiver operating characteristic curve of 0.87. A threshold of 80 IU/L yielded sensitivity of 83.8% and specificity of 83.1%. The areas under the curve for amylase and lipase were 0.67 and 0.72, respectively. Children evaluated for physical abuse with transaminase levels >80 IU/L should undergo definitive testing for abdominal injury.

Validation of a Nutrition Screening Tool for Pediatric Patients with Cystic Fibrosis.

PubMed

Souza Dos Santos Simon, Miriam Isabel; Forte, Gabriele Carra; da Silva Pereira, Juliane; da Fonseca Andrade Procianoy, Elenara; Drehmer, Michele

2016-05-01

In cystic fibrosis (CF), nutrition diagnosis is of critical relevance because the early identification of nutrition-related compromise enables early, adequate intervention and, consequently, influences patient prognosis. Up to now, there has not been a validated nutrition screening tool that takes into consideration clinical variables. To validate a specific nutritional risk screening tool for patients with CF based on clinical variables, anthropometric parameters, and dietary intake. Cross-sectional study. The nutrition screening tool was compared with a risk screening tool proposed by McDonald and the Cystic Fibrosis Foundation criteria. Patients aged 6 to 18 years, with a diagnosis of CF confirmed by two determinations of elevated chloride level in sweat (sweat test) and/or by identification of two CF-associated genetic mutations who were receiving follow-up care through the outpatient clinic of a Cystic Fibrosis Treatment Center. Earlier identification of nutritional risk in CF patients aged 6 to 18 years when a new screening tool was applied. Agreement among the tested methods was assessed by means of the kappa coefficient for categorical variables. Sensitivity, specificity, and accuracy values were calculated. The significance level was set at 5% (P<0.05). Statistical analyses were carried out in PASW Statistics for Windows version 18.0 (2009, SPSS Inc). Eighty-two patients (49% men, aged 6 to 18 years) were enrolled in the study. The agreement between the proposed screening tool and the tool for screening nutritional risk for CF by the McDonald method was good (κ=0.804; P<0.001) and the sensitivity and specificity was 85% and 95%, respectively. Agreement with the Cystic Fibrosis Foundation criteria was lower (κ=0.418; P<0.001), and the sensitivity and specificity were both 72%. The proposed screening tool with defined clinical variables promotes earlier identification of nutritional risk in pediatric patients with CF. Copyright © 2016 Academy of Nutrition and Dietetics. Published by Elsevier Inc. All rights reserved.

Multimodal lung cancer screening using the ITALUNG biomarker panel and low dose computed tomography. Results of the ITALUNG biomarker study.

PubMed

Carozzi, Francesca Maria; Bisanzi, Simonetta; Carrozzi, Laura; Falaschi, Fabio; Lopes Pegna, Andrea; Mascalchi, Mario; Picozzi, Giulia; Peluso, Marco; Sani, Cristina; Greco, Luana; Ocello, Cristina; Paci, Eugenio

2017-07-01

Asymptomatic high-risk subjects, randomized in the intervention arm of the ITALUNG trial (1,406 screened for lung cancer), were enrolled for the ITALUNG biomarker study (n = 1,356), in which samples of blood and sputum were analyzed for plasma DNA quantification (cut off 5 ng/ml), loss of heterozygosity and microsatellite instability. The ITALUNG biomarker panel (IBP) was considered positive if at least one of the two biomarkers included in the panel was positive. Subjects with and without lung cancer diagnosis at the end of the screening cycle with LDCT (n = 517) were evaluated. Out of 18 baseline screen detected lung cancer cases, 17 were IBP positive (94%). Repeat screen-detected lung cancer cases were 18 and 12 of them positive at baseline IBP test (66%). Interval cancer cases (2-years) and biomarker tests after a suspect Non Calcific Nodule follow-up were investigated. The single test versus multimodal screening measures of accuracy were compared in a simulation within the screened ITALUNG intervention arm, considering screen-detected and interval cancer cases. Sensitivity was 90% at baseline screening. Specificity was 71 and 61% for LDCT and IBP as baseline single test, and improved at 89% with multimodal, combined screening. The positive predictive value was 4.3% for LDCT at baseline and 10.6% for multimodal screening. Multimodal screening could improve the screening efficiency at baseline and strategies for future implementation are discussed. If IBP was used as primary screening test, the LDCT burden might decrease of about 60%. © 2017 UICC.

Screening for Autism Spectrum Disorders in Children With Down Syndrome

PubMed Central

DiGuiseppi, Carolyn; Hepburn, Susan; Davis, Jonathan M.; Fidler, Deborah J.; Hartway, Sara; Lee, Nancy Raitano; Miller, Lisa; Ruttenber, Margaret; Robinson, Cordelia

2015-01-01

Objective We assessed the prevalence of autism spectrum disorders (ASD) and screening test characteristics in children with Down syndrome. Method Eligible children born in a defined geographic area between January 1, 1996, and December 31, 2003, were recruited through a population-based birth defects registry and community outreach, then screened with the modified checklist for autism in toddlers or social communication questionnaire, as appropriate. Screen-positive children and a random sample of screen-negative children underwent developmental evaluation. Results We screened 123 children (27.8% of the birth cohort). Mean age was 73.4 months (range, 31–142). Compared to screen-negative children, screen-positive children had similar sociodemo-graphic characteristics but a lower mean developmental quotient (mean difference: 11.0; 95% confidence interval: 4.8–17.3). Weighted prevalences of autistic disorder and total ASD were 6.4% (95% confidence interval [CI]: 2.6%–11.6%) and 18.2% (95% CI: 9.7%–26.8%), respectively. The estimated minimum ASD prevalence, accounting for unscreened children, is 5.1% (95% CI: 3.3%–7.4%). ASD prevalence increased with greater cognitive impairment. Screening test sensitivity was 87.5% (95% CI: 66.6%–97.7%); specificity was 49.9% (95% CI: 37.0%–61.4%). Conclusion The prevalence of ASD among children with Down syndrome aged 2 to 11 years is substantially higher than in the general population. The modified checklist for autism in toddlers and social communication questionnaire were highly sensitive in children with Down syndrome but could result in many false positive tests if universal screening were implemented using current algorithms. Research needs include development of specific ASD screening algorithms and improved diagnostic discrimination in children with Down syndrome. Timely identification of these co-occurring diagnoses is essential so appropriate interventions can be provided. PMID:20375732

Screening older adults at risk of falling with the Tinetti balance scale.

PubMed

Raîche, M; Hébert, R; Prince, F; Corriveau, H

2000-09-16

In a prospective study of 225 community dwelling people 75 years and older, we tested the validity of the Tinetti balance scale to predict individuals who will fall at least once during the following year. A score of 36 or less identified 7 of 10 fallers with 70% sensitivity and 52% specificity. With this cut-off score, 53% of the individuals were screened positive and presented a two-fold risk of falling. These characteristics support the use of this test to screen older people at risk of falling in order to include them in a preventive intervention.

A comprehensive evaluation of various sensitivity analysis methods: A case study with a hydrological model

DOE PAGES

Gan, Yanjun; Duan, Qingyun; Gong, Wei; ...

2014-01-01

Sensitivity analysis (SA) is a commonly used approach for identifying important parameters that dominate model behaviors. We use a newly developed software package, a Problem Solving environment for Uncertainty Analysis and Design Exploration (PSUADE), to evaluate the effectiveness and efficiency of ten widely used SA methods, including seven qualitative and three quantitative ones. All SA methods are tested using a variety of sampling techniques to screen out the most sensitive (i.e., important) parameters from the insensitive ones. The Sacramento Soil Moisture Accounting (SAC-SMA) model, which has thirteen tunable parameters, is used for illustration. The South Branch Potomac River basin nearmore » Springfield, West Virginia in the U.S. is chosen as the study area. The key findings from this study are: (1) For qualitative SA methods, Correlation Analysis (CA), Regression Analysis (RA), and Gaussian Process (GP) screening methods are shown to be not effective in this example. Morris One-At-a-Time (MOAT) screening is the most efficient, needing only 280 samples to identify the most important parameters, but it is the least robust method. Multivariate Adaptive Regression Splines (MARS), Delta Test (DT) and Sum-Of-Trees (SOT) screening methods need about 400–600 samples for the same purpose. Monte Carlo (MC), Orthogonal Array (OA) and Orthogonal Array based Latin Hypercube (OALH) are appropriate sampling techniques for them; (2) For quantitative SA methods, at least 2777 samples are needed for Fourier Amplitude Sensitivity Test (FAST) to identity parameter main effect. McKay method needs about 360 samples to evaluate the main effect, more than 1000 samples to assess the two-way interaction effect. OALH and LPτ (LPTAU) sampling techniques are more appropriate for McKay method. For the Sobol' method, the minimum samples needed are 1050 to compute the first-order and total sensitivity indices correctly. These comparisons show that qualitative SA methods are more efficient but less accurate and robust than quantitative ones.« less

First day of life pulse oximetry screening to detect congenital heart defects.

PubMed

Meberg, Alf; Brügmann-Pieper, Sabine; Due, Reidar; Eskedal, Leif; Fagerli, Ingebjørg; Farstad, Teresa; Frøisland, Dag Helge; Sannes, Catharina Hovland; Johansen, Ole Jakob; Keljalic, Jasmina; Markestad, Trond; Nygaard, Egil Andre; Røsvik, Alet; Silberg, Inger Elisabeth

2008-06-01

To evaluate the efficacy of first day of life pulse oximetry screening to detect congenital heart defects (CHDs). We performed a population-based prospective multicenter study of postductal (foot) arterial oxygen saturation (SpO(2)) in apparently healthy newborns after transfer from the delivery suite to the nursery. SpO(2) < 95% led to further diagnostic evaluations. Of 57,959 live births, 50,008 (86%) were screened. In the screened population, 35 CHDs were [corrected] classified as critical (ductus dependent, cyanotic). CHDs were prospectively registered and diagnosed in 658/57,959 (1.1%) [corrected] Of the infants screened, 324 (0.6%) failed the test. Of these, 43 (13%) had CHDs (27 critical), and 134 (41%) had pulmonary diseases or other disorders. The remaining 147 infants (45%) were healthy with transitional circulation. The median age for babies with CHDs at failing the test was 6 hours (range, 1-21 hours). For identifying critical CHDs, the pulse oximetry screening had a sensitivity rate of 77.1% (95% CI, 59.4-89.0), specificity rate of 99.4% (95% CI, 99.3-99.5), and a false-positive rate of 0.6% (95% CI, 0.5-0.7). Early pulse oximetry screening promotes early detection of critical CHDs and other potentially severe diseases. The sensitivity rate for detecting critical CHDs is high, and the false-positive rate is low.

Early language screening in city and Hackney: the concurrent validity of a measure designed for use with 2 1/2-year-olds.

PubMed

Law, J

1994-01-01

This paper reports data relating to the development of a screening test for language impairment in 2 1/2-year-old children. The screening test itself has previously been described. The results of a pilot study and a larger community study are reported. In all, 34 children were included in the pilot study and 1015 in the community study. The reference test selected was the Reynell Developmental Language Scales and the cut-off adopted 1.5 standard deviations below the mean for either the expressive or the receptive scale of the test concerned. The pass mark on the screening test was ascertained using receiver operating characteristics (ROC). The validity is reported given the cut-off identified. The specificity, sensitivity and both positive and negative predictive abilities are reported for both the pilot and the subsequent study. The application of the test is discussed in the context of the current debate about early identification.

Comparison of the Substance Use Brief Screen (SUBS) to the AUDIT-C and ASSIST for detecting unhealthy alcohol and drug use in a population of hospitalized smokers.

PubMed

Han, Benjamin H; Sherman, Scott E; Link, Alissa R; Wang, Binhuan; McNeely, Jennifer

2017-08-01

Hospitalized patients have high rates of unhealthy substance use, which has important impacts on health both during and after hospitalization, but is infrequently identified in the absence of screening. The Substance Use Brief Screen (SUBS) was developed as a brief, self-administered instrument to identify use of tobacco, alcohol, illicit drugs, and non-medical use of prescription drugs, and was previously validated in primary care patients. This study assessed the diagnostic accuracy of the SUBS in comparison to longer screening instruments to identify unhealthy and high-risk alcohol and drug use in hospitalized current smokers. Participants were 439 patients, aged 18 and older, who were admitted to either two urban safety-net hospitals in New York City and enrolled in a smoking cessation trial. We measured the performance of the SUBS for identifying illicit drug and non-medical use of prescription drugs in comparison to a modified Alcohol, Smoking and Substance Involvement Screening Test (ASSIST) and its performance for identifying excessive alcohol use in comparison to the Alcohol Use Disorders Identification Test-Consumption (AUDIT-C). At the standard cutoff (response other than 'never' indicates a positive screen), the SUBS had a sensitivity of 98% (95% CI 95-100%) and specificity of 61% (95% CI 55-67%) for unhealthy alcohol use, a sensitivity of 85% (95% CI 80-90%) and specificity of 75% (95% CI 78-87%) for illicit drug use, and a sensitivity of 73% (95% CI 61-83%) and specificity of 83% (95% CI 78-87%) for prescription drug non-medical use. For identifying high-risk use, a higher cutoff (response of '3 or more days' of use indicates a positive screen), the SUBS retained high sensitivity (77-90%), and specificity was 62-88%. The SUBS can be considered as an alternative to longer screening instruments, which may fit more easily into busy inpatient settings. Further study is needed to evaluate its validity using gold standard measures in hospitalized populations. Copyright © 2017 Elsevier Inc. All rights reserved.

Type 2 diabetes and cardiac autonomic neuropathy screening using dynamic pupillometry

PubMed Central

Lerner, Alana G.; Bernabé-Ortiz, Antonio; Ticse, Ray; Hernandez, Arturo; Huaylinos, Yvonne; Pinto, Miguel E.; Málaga, Germán; Checkley, William; Gilman, Robert H.; Miranda, J. Jaime

2015-01-01

Aim To determine if changes in pupillary response are useful as a screening tool for diabetes and to assess whether pupillometry is associated with cardiac autonomic neuropathy. Methods We conducted a cross-sectional study with participants drawn from two settings: a hospital and a community site. At the community site, individuals with newly diagnosed diabetes as well as a random sample of control individuals without diabetes, confirmed by oral glucose tolerance test, were selected. Participants underwent an LED light stimulus test and eight pupillometry variables were measured. Outcomes were diabetes, defined by oral glucose tolerance test, and cardiac autonomic dysfunction, determined by a positive readout on two of four diagnostic tests: heart rate response to the Valsalva manoeuvre; orthostatic hypotension; 30:15 ratio; and expiration-to-inspiration ratio. The area under the curve, best threshold, sensitivity and specificity of each pupillometry variable was calculated. Results Data from 384 people, 213 with diabetes, were analysed. The mean (±SD) age of the people with diabetes was 58.6 (±8.2) years and in the control subjects it was 56.1 (±8.6) years. When comparing individuals with and without diabetes, the amplitude of the pupil reaction had the highest area under the curve [0.69 (sensitivity: 78%; specificity: 55%)]. Cardiac autonomic neuropathy was present in 51 of the 138 people evaluated (37.0%; 95% CI 28.8–45.1). To diagnose cardiac autonomic neuropathy, two pupillometry variables had the highest area under the curve: baseline pupil radius [area under the curve: 0.71 (sensitivity: 51%; specificity: 84%)], and amplitude of the pupil reaction [area under the curve: 070 (sensitivity: 82%; specificity: 55%)]. Conclusions Pupillometry is an inexpensive technique to screen for diabetes and cardiac autonomic neuropathy, but it does not have sufficient accuracy for clinical use as a screening tool. PMID:25761508

Type 2 diabetes and cardiac autonomic neuropathy screening using dynamic pupillometry.

PubMed

Lerner, A G; Bernabé-Ortiz, A; Ticse, R; Hernandez, A; Huaylinos, Y; Pinto, M E; Málaga, G; Checkley, W; Gilman, R H; Miranda, J J

2015-11-01

To determine if changes in pupillary response are useful as a screening tool for diabetes and to assess whether pupillometry is associated with cardiac autonomic neuropathy. We conducted a cross-sectional study with participants drawn from two settings: a hospital and a community site. At the community site, individuals with newly diagnosed diabetes as well as a random sample of control individuals without diabetes, confirmed by oral glucose tolerance test, were selected. Participants underwent an LED light stimulus test and eight pupillometry variables were measured. Outcomes were diabetes, defined by oral glucose tolerance test, and cardiac autonomic dysfunction, determined by a positive readout on two of four diagnostic tests: heart rate response to the Valsalva manoeuvre; orthostatic hypotension; 30:15 ratio; and expiration-to-inspiration ratio. The area under the curve, best threshold, sensitivity and specificity of each pupillometry variable was calculated. Data from 384 people, 213 with diabetes, were analysed. The mean (±sd) age of the people with diabetes was 58.6 (±8.2) years and in the control subjects it was 56.1 (±8.6) years. When comparing individuals with and without diabetes, the amplitude of the pupil reaction had the highest area under the curve [0.69 (sensitivity: 78%; specificity: 55%)]. Cardiac autonomic neuropathy was present in 51 of the 138 people evaluated (37.0%; 95% CI 28.8-45.1). To diagnose cardiac autonomic neuropathy, two pupillometry variables had the highest area under the curve: baseline pupil radius [area under the curve: 0.71 (sensitivity: 51%; specificity: 84%)], and amplitude of the pupil reaction [area under the curve: 0.70 (sensitivity: 82%; specificity: 55%)]. Pupillometry is an inexpensive technique to screen for diabetes and cardiac autonomic neuropathy, but it does not have sufficient accuracy for clinical use as a screening tool. © 2015 The Authors. Diabetic Medicine © 2015 Diabetes UK.

Zebrafish embryotoxicity test for developmental (neuro)toxicity: Demo case of an integrated screening approach system using anti-epileptic drugs.

PubMed

Beker van Woudenberg, Anna; Snel, Cor; Rijkmans, Eke; de Groot, Didima; Bouma, Marga; Hermsen, Sanne; Piersma, Aldert; Menke, Aswin; Wolterbeek, André

2014-11-01

To improve the predictability of the zebrafish embryotoxicity test (ZET) for developmental (neuro)toxicity screening, we used a multiple-endpoints strategy, including morphology, motor activity (MA), histopathology and kinetics. The model compounds used were antiepileptic drugs (AEDs): valproic acid (VPA), carbamazepine (CBZ), ethosuximide (ETH) and levetiracetam (LEV). For VPA, histopathology was the most sensitive parameter, showing effects already at 60μM. For CBZ, morphology and MA were the most sensitive parameters, showing effects at 180μM. For ETH, all endpoints showed similar sensitivity (6.6mM), whereas MA was the most sensitive parameter for LEV (40mM). Inclusion of kinetics did not alter the absolute ranking of the compounds, but the relative potency was changed considerably. Taking all together, this demo-case study showed that inclusion of multiple-endpoints in ZET may increase the sensitivity of the assay, contribute to the elucidation of the mode of toxic action and to a better definition of the applicability domain of ZET. Copyright © 2014 Elsevier Inc. All rights reserved.

Public stated preferences and predicted uptake for genome-based colorectal cancer screening

PubMed Central

2014-01-01

Background Emerging developments in nanomedicine allow the development of genome-based technologies for non-invasive and individualised screening for diseases such as colorectal cancer. The main objective of this study was to measure user preferences for colorectal cancer screening using a nanopill. Methods A discrete choice experiment was used to estimate the preferences for five competing diagnostic techniques including the nanopill and iFOBT. Alternative screening scenarios were described using five attributes namely: preparation involved, sensitivity, specificity, complication rate and testing frequency. Fourteen random and two fixed choice tasks, each consisting of three alternatives, were offered to 2225 individuals. Data were analysed using the McFadden conditional logit model. Results Thirteen hundred and fifty-six respondents completed the questionnaire. The most important attributes (and preferred levels) were the screening technique (nanopill), sensitivity (100%) and preparation (no preparation). Stated screening uptake for the nanopill was 79%, compared to 76% for iFOBT. In the case of screening with the nanopill, the percentage of people preferring not to be screened would be reduced from 19.2% (iFOBT) to 16.7%. Conclusions Although the expected benefits of nanotechnology based colorectal cancer screening are improved screening uptake, assuming more accurate test results and less preparation involved, the relative preference of the nanopill is only slightly higher than the iFOBT. Estimating user preferences during the development of diagnostic technologies could be used to identify relative performance, including perceived benefits and harms compared to competitors allowing for significant changes to be made throughout the process of development. PMID:24642027

Comparison of methods for in-house screening of HLA-B*57:01 to prevent abacavir hypersensitivity in HIV-1 care.

PubMed

De Spiegelaere, Ward; Philippé, Jan; Vervisch, Karen; Verhofstede, Chris; Malatinkova, Eva; Kiselinova, Maja; Trypsteen, Wim; Bonczkowski, Pawel; Vogelaers, Dirk; Callens, Steven; Ruelle, Jean; Kabeya, Kabamba; De Wit, Stephane; Van Acker, Petra; Van Sandt, Vicky; Emonds, Marie-Paule; Coucke, Paul; Sermijn, Erica; Vandekerckhove, Linos

2015-01-01

Abacavir is a nucleoside reverse transcriptase inhibitor used as part of combination antiretroviral therapy in HIV-1-infected patients. Because this drug can cause a hypersensitivity reaction that is correlated with the presence of the HLA-B*57:01 allotype, screening for the presence of HLA-B*57:01 is recommended before abacavir initiation. Different genetic assays have been developed for HLA-B*57:01 screening, each with specific sensitivity, turnaround time and assay costs. Here, a new real-time PCR (qPCR) based analysis is described and compared to sequence specific primer PCR with capillary electrophoresis (SSP PCR CE) on 149 patient-derived samples, using sequence specific oligonucleotide hybridization combined with high resolution SSP PCR as gold standard. In addition to these PCR based methods, a complementary approach was developed using flow cytometry with an HLA-B17 specific monoclonal antibody as a pre-screening assay to diminish the number of samples for genetic testing. All three assays had a maximum sensitivity of >99. However, differences in specificity were recorded, i.e. 84.3%, 97.2% and >99% for flow cytometry, qPCR and SSP PCR CE respectively. Our data indicate that the most specific and sensitive of the compared methods is the SSP PCR CE. Flow cytometry pre-screening can substantially decrease the number of genetic tests for HLA-B*57:01 typing in a clinical setting.

Laboratory evaluation on the sensitivity and specificity of a novel and rapid detection method for malaria diagnosis based on magneto-optical technology (MOT).

PubMed

Mens, Petra F; Matelon, Raphael J; Nour, Bakri Y M; Newman, Dave M; Schallig, Henk D F H

2010-07-19

This study describes the laboratory evaluation of a novel diagnostic platform for malaria. The Magneto Optical Test (MOT) is based on the bio-physical detection of haemozoin in clinical samples. Having an assay time of around one minute, it offers the potential of high throughput screening. Blood samples of confirmed malaria patients from different regions of Africa, patients with other diseases and healthy non-endemic controls were used in the present study. The samples were analysed with two reference tests, i.e. an histidine rich protein-2 based rapid diagnostic test (RDT) and a conventional Pan-Plasmodium PCR, and the MOT as index test. Data were entered in 2 x 2 tables and analysed for sensitivity and specificity. The agreement between microscopy, RDT and PCR and the MOT assay was determined by calculating Kappa values with a 95% confidence interval. The observed sensitivity/specificity of the MOT test in comparison with clinical description, RDT or PCR ranged from 77.2 - 78.8% (sensitivity) and from 72.5 - 74.6% (specificity). In general, the agreement between MOT and the other assays is around 0.5 indicating a moderate agreement between the reference and the index test. However, when RDT and PCR are compared to each other, an almost perfect agreement can be observed (k = 0.97) with a sensitivity and specificity of >95%. Although MOT sensitivity and specificity are currently not yet at a competing level compared to other diagnostic test, such as PCR and RDTs, it has a potential to rapidly screen patients for malaria in endemic as well as non-endemic countries.

Variability of Offending Allergens of Allergic Rhinitis According to Age: Optimization of Skin Prick Test Allergens

PubMed Central

Lee, Ji-Eun; Ahn, Jae-Chul; Han, Doo Hee; Kim, Dong-Young; Kim, Jung-Whun; Cho, Sang-Heon; Park, Heung-Woo

2014-01-01

Purpose This study evaluates offending allergens in patients with allergic rhinitis (AR) according to age that establish a minimal panel for skin prick test (SPT) allergens required to identify if a patient is sensitized. Methods We retrospectively analyzed SPT results according to age to determine the minimum test battery panel necessary to screen at least 93%-95% of AR patients. Allergic skin tests (common airborne indoor and outdoor allergens) were performed on 7,182 patients from January 2007 to June 2011. All patients were classified into 9 groups according to age; subsequently, we investigated offending allergens by age group. Results A total of 5,032 (70.1%) patients were found sensitized to at least one of the 55 aeroallergen extracts tested. The annual ranking of offending allergens was not significantly different from each other over the past 5 years. House dust mites (HDM) were the most prevalent allergens ranked from first to third for all 5 years. The allergens in the minimum test panel differed slightly among all age groups; in addition, the types of sensitized allergen sources were more diverse in the older versus younger age group. HDM covered a larger proportion of the sensitized allergens in the younger age group versus the older age group. Testing with 5 allergens (Dermatophagoides farinae, Tetranychus urticae, oak, mugwort and cockroach) adequately identified over 90% of the sensitized patients. Conclusions A SPT with around 5-7 allergens adequately detected most of the sensitization in the majority of the age groups in Korea. However, this study suggests that physicians perform the SPT with appropriately selected allergens in each age category for the screening of AR. PMID:24404393

Variability of offending allergens of allergic rhinitis according to age: optimization of skin prick test allergens.

PubMed

Lee, Ji-Eun; Ahn, Jae-Chul; Han, Doo Hee; Kim, Dong-Young; Kim, Jung-Whun; Cho, Sang-Heon; Park, Heung-Woo; Rhee, Chae-Seo

2014-01-01

This study evaluates offending allergens in patients with allergic rhinitis (AR) according to age that establish a minimal panel for skin prick test (SPT) allergens required to identify if a patient is sensitized. We retrospectively analyzed SPT results according to age to determine the minimum test battery panel necessary to screen at least 93%-95% of AR patients. Allergic skin tests (common airborne indoor and outdoor allergens) were performed on 7,182 patients from January 2007 to June 2011. All patients were classified into 9 groups according to age; subsequently, we investigated offending allergens by age group. A total of 5,032 (70.1%) patients were found sensitized to at least one of the 55 aeroallergen extracts tested. The annual ranking of offending allergens was not significantly different from each other over the past 5 years. House dust mites (HDM) were the most prevalent allergens ranked from first to third for all 5 years. The allergens in the minimum test panel differed slightly among all age groups; in addition, the types of sensitized allergen sources were more diverse in the older versus younger age group. HDM covered a larger proportion of the sensitized allergens in the younger age group versus the older age group. Testing with 5 allergens (Dermatophagoides farinae, Tetranychus urticae, oak, mugwort and cockroach) adequately identified over 90% of the sensitized patients. A SPT with around 5-7 allergens adequately detected most of the sensitization in the majority of the age groups in Korea. However, this study suggests that physicians perform the SPT with appropriately selected allergens in each age category for the screening of AR.

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

PubMed

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

2015-05-15

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

An evaluation of the SD Bioline HIV/syphilis duo test.

PubMed

Holden, Jeffrey; Goheen, Joshua; Jett-Goheen, Mary; Barnes, Mathilda; Hsieh, Yu-Hsiang; Gaydos, Charlotte A

2018-01-01

Many health agencies now recommend routine HIV and syphilis testing for pregnant women and most-at-risk populations such as men who have sex with men. With the increased availability of highly sensitive, low cost rapid point-of-care tests, the ability to meet those recommendations has increased, granting wider access to quick and accurate diagnoses. Using blood specimens collected from a Baltimore City Health Department (BCHD) sexually transmitted infection clinic, we evaluated the SD Bioline HIV/Syphilis Duo, a rapid test that simultaneously detects antibodies to HIV and syphilis and has the potential to further benefit clinics and patients by reducing costs, testing complexity, and patient wait times. SD DUO HIV sensitivity and specificity, when compared to BCHD results, were 91.7 and 99.5%, respectively. SD DUO syphilis sensitivity and specificity, when compared to rapid plasma reagin, were 85.7 and 96.8%, respectively, and 69.7 and 99.7%, respectively, when compared to Treponema pallidum particle agglutination (TPPA). SD DUO syphilis sensitivity and specificity, when compared to a traditional screening algorithm, improved to 92.3 and 100%, respectively, and improved to 72.9 and 99.7%, respectively, when compared to a reverse screening algorithm. The HIV component of the SD DUO performed moderately well. However, results for the SD DUO syphilis component, when compared to TPPA, support the need for further testing and assessment.

Hierarchical screening for multiple mental disorders.

PubMed

Batterham, Philip J; Calear, Alison L; Sunderland, Matthew; Carragher, Natacha; Christensen, Helen; Mackinnon, Andrew J

2013-10-01

There is a need for brief, accurate screening when assessing multiple mental disorders. Two-stage hierarchical screening, consisting of brief pre-screening followed by a battery of disorder-specific scales for those who meet diagnostic criteria, may increase the efficiency of screening without sacrificing precision. This study tested whether more efficient screening could be gained using two-stage hierarchical screening than by administering multiple separate tests. Two Australian adult samples (N=1990) with high rates of psychopathology were recruited using Facebook advertising to examine four methods of hierarchical screening for four mental disorders: major depressive disorder, generalised anxiety disorder, panic disorder and social phobia. Using K6 scores to determine whether full screening was required did not increase screening efficiency. However, pre-screening based on two decision tree approaches or item gating led to considerable reductions in the mean number of items presented per disorder screened, with estimated item reductions of up to 54%. The sensitivity of these hierarchical methods approached 100% relative to the full screening battery. Further testing of the hierarchical screening approach based on clinical criteria and in other samples is warranted. The results demonstrate that a two-phase hierarchical approach to screening multiple mental disorders leads to considerable increases efficiency gains without reducing accuracy. Screening programs should take advantage of prescreeners based on gating items or decision trees to reduce the burden on respondents. © 2013 Elsevier B.V. All rights reserved.

Single Measure and Gated Screening Approaches for Identifying Students At-Risk for Academic Problems: Implications for Sensitivity and Specificity

ERIC Educational Resources Information Center

Van Norman, Ethan R.; Nelson, Peter M.; Klingbeil, David A.

2017-01-01

Educators need recommendations to improve screening practices without limiting students' instructional opportunities. Repurposing previous years' state test scores has shown promise in identifying at-risk students within multitiered systems of support. However, researchers have not directly compared the diagnostic accuracy of previous years' state…

Cost-effectiveness of cervical cancer screening with primary human papillomavirus testing in Norway.

PubMed

Burger, E A; Ortendahl, J D; Sy, S; Kristiansen, I S; Kim, J J

2012-04-24

New screening technologies and vaccination against human papillomavirus (HPV), the necessary cause of cervical cancer, may impact optimal approaches to prevent cervical cancer. We evaluated the cost-effectiveness of alternative screening strategies to inform cervical cancer prevention guidelines in Norway. We leveraged the primary epidemiologic and economic data from Norway to contextualise a simulation model of HPV-induced cervical cancer. The current cytology-only screening was compared with strategies involving cytology at younger ages and primary HPV-based screening at older ages (31/34+ years), an option being actively deliberated by the Norwegian government. We varied the switch-age, screening interval, and triage strategies for women with HPV-positive results. Uncertainty was evaluated in sensitivity analysis. Current cytology-only screening was less effective and more costly than strategies that involve switching to primary HPV testing in older ages. For unvaccinated women, switching at age 34 years to primary HPV testing every 4 years was optimal given the Norwegian cost-effectiveness threshold ($83,000 per year of life saved). For vaccinated women, a 6-year screening interval was cost-effective. When we considered a wider range of strategies, we found that an earlier switch to HPV testing (at age 31 years) may be preferred. Strategies involving a switch to HPV testing for primary screening in older women is expected to be cost-effective compared with current recommendations in Norway.

Asymptomatic bacteriuria in pregnant women attending Boo-Ali Hospital Tehran Iran: Urine analysis vs. urine culture

PubMed Central

Etminan-Bakhsh, Mina; Tadi, Sima; Darabi, Roksana

2017-01-01

Background Asymptomatic bacteriuria is one of the common problems in pregnancy. Asymptomatic bacteriuria is associated with pyelonephritis, preterm labor and low birth weight infants. The physiological and anatomical changes in pregnancy facilitate urinary tract infection (UTI) during pregnancy. Several tests are available for diagnosis of asymptomatic bacteriuria. The urine culture is a gold standard diagnostic test for asymptomatic bacteriuria but it is expensive and time-consuming. Screening methods may be useful in detecting high-risk pregnant women for asymptomatic bacteriuria. Objective The aim of the present study was to compare urine analysis as a rapid screening test to urine culture in diagnosis of asymptomatic bacteriuria. Methods A total of 123 pregnant women attending the obstetrics clinic of Boo-Ali hospital in Tehran, Iran from March 2013 to September 2014 were included in the present diagnostic cross-sectional study. One hundred twenty three mid-stream urine samples were inoculated into cultures and were processed by dipstick (nitrite test and leucocyte esterase test) and microscopic pus cell count. The sensitivity, specificity, positive predictive value and negative predictive value of nitrite test, leucocyte esterase test and microscopic pus cell count were compared with urine culture in diagnosis of asymptomatic bacteriuria by using SPSS version 19. Results Of 123 urine samples, significant asymptomatic bacteriuria (≥104 cfu/Ml) was detected in 8 (6.5%) subjects. The sensitivity and specificity of nitrite test were 37% and 100% respectively. The sensitivity of pus cell count alone and leucocyte esterase test alone were 100% but the specificity of them were 64% and 65% respectively. We found high negative predictive value by Pus cell count and the leucocyte esterase test (100%) and low positive predictive value by them (16% and 17% respectively). Conclusion Urine culture is the most useful test for diagnosis of asymptomatic bacteriuria. None of our screening tests had a sensitivity and specificity of 100%, whereas we can only refer the pregnant women with positive leucocyte esterase test and significant pyuria to the urine culture. PMID:29403616

Applying under-sampling techniques and cost-sensitive learning methods on risk assessment of breast cancer.

PubMed

Hsu, Jia-Lien; Hung, Ping-Cheng; Lin, Hung-Yen; Hsieh, Chung-Ho

2015-04-01

Breast cancer is one of the most common cause of cancer mortality. Early detection through mammography screening could significantly reduce mortality from breast cancer. However, most of screening methods may consume large amount of resources. We propose a computational model, which is solely based on personal health information, for breast cancer risk assessment. Our model can be served as a pre-screening program in the low-cost setting. In our study, the data set, consisting of 3976 records, is collected from Taipei City Hospital starting from 2008.1.1 to 2008.12.31. Based on the dataset, we first apply the sampling techniques and dimension reduction method to preprocess the testing data. Then, we construct various kinds of classifiers (including basic classifiers, ensemble methods, and cost-sensitive methods) to predict the risk. The cost-sensitive method with random forest classifier is able to achieve recall (or sensitivity) as 100 %. At the recall of 100 %, the precision (positive predictive value, PPV), and specificity of cost-sensitive method with random forest classifier was 2.9 % and 14.87 %, respectively. In our study, we build a breast cancer risk assessment model by using the data mining techniques. Our model has the potential to be served as an assisting tool in the breast cancer screening.

Optimal Hemoglobin A1c Levels for Screening of Diabetes and Prediabetes in the Japanese Population.

PubMed

Shimodaira, Masanori; Okaniwa, Shinji; Hanyu, Norinao; Nakayama, Tomohiro

2015-01-01

The aim of this study was to evaluate the utility of hemoglobin A1c (HbA1c) to identify individuals with diabetes and prediabetes in the Japanese population. A total of 1372 individuals without known diabetes were selected for this study. A 75 g oral glucose tolerance test (OGTT) was used to diagnose diabetes and prediabetes. The ability of HbA1c to detect diabetes and prediabetes was investigated using receiver operating characteristic (ROC) analysis. The kappa (κ) coefficient was used to test the agreement between HbA1c categorization and OGTT-based diagnosis. ROC analysis demonstrated that HbA1c was a good test to identify diabetes and prediabetes, with areas under the curve of 0.918 and 0.714, respectively. Optimal HbA1c cutoffs for diagnosing diabetes and prediabetes were 6.0% (sensitivity 83.7%, specificity 87.6%) and 5.7% (sensitivity 60.6%, specificity 72.1%), respectively, although the cutoff for prediabetes showed low accuracy (67.6%) and a high false-negative rate (39.4%). Agreement between HbA1c categorization and OGTT-based diagnosis was low in diabetes (κ = 0.399) and prediabetes (κ = 0.324). In Japanese subjects, the HbA1c cutoff of 6.0% had appropriate sensitivity and specificity for diabetes screening, whereas the cutoff of 5.7% had modest sensitivity and specificity in identifying prediabetes. Thus, HbA1c may be inadequate as a screening tool for prediabetes.

Sensitivity and specificity of the Confusion Assessment Method for the Intensive Care Unit (CAM-ICU) and the Intensive Care Delirium Screening Checklist (ICDSC) for detecting post-cardiac surgery delirium: A single-center study in Japan.

PubMed

Nishimura, Katsuji; Yokoyama, Kanako; Yamauchi, Noriko; Koizumi, Masako; Harasawa, Nozomi; Yasuda, Taeko; Mimura, Chizuru; Igita, Hazuki; Suzuki, Eriko; Uchiide, Yoko; Seino, Yusuke; Nomura, Minoru; Yamazaki, Kenji; Ishigooka, Jun

2016-01-01

To compare the Confusion Assessment Method for the Intensive Care Unit (CAM-ICU) and the Intensive Care Delirium Screening Checklist (ICDSC) for detecting post-cardiac surgery delirium. These tools have not been tested in a specialized cardio-surgical ICU. Sensitivities and specificities of each tool were assessed in a cardio-surgical ICU in Japan by two trained nurses independently. Results were compared with delirium diagnosed by psychiatrists using the Diagnostic and Statistical Manual of Mental Disorders, 4th Edition, Text Revision. There were 110 daily, paired assessments in 31 patients. The CAM-ICU showed 38% sensitivity and 100% specificity for both nurses. All 20 false-negative cases resulted from high scores in the auditory attention screening in CAM-ICU. The ICDSC showed 97% and 94% sensitivity, and 97% and 91% specificity for the two nurses (cutoff ≥4). In a Japanese cardio-surgical ICU, the ICDSC had a higher sensitivity than the CAM-ICU. Copyright © 2016 Elsevier Inc. All rights reserved.

Which BRCA genetic testing programs are ready for implementation in health care? A systematic review of economic evaluations.

PubMed

D'Andrea, Elvira; Marzuillo, Carolina; De Vito, Corrado; Di Marco, Marco; Pitini, Erica; Vacchio, Maria Rosaria; Villari, Paolo

2016-12-01

There is considerable evidence regarding the efficacy and effectiveness of BRCA genetic testing programs, but whether they represent good use of financial resources is not clear. Therefore, we aimed to identify the main health-care programs for BRCA testing and to evaluate their cost-effectiveness. We performed a systematic review of full economic evaluations of health-care programs involving BRCA testing. Nine economic evaluations were included, and four main categories of BRCA testing programs were identified: (i) population-based genetic screening of individuals without cancer, either comprehensive or targeted based on ancestry; (ii) family history (FH)-based genetic screening, i.e., testing individuals without cancer but with FH suggestive of BRCA mutation; (iii) familial mutation (FM)-based genetic screening, i.e., testing individuals without cancer but with known familial BRCA mutation; and (iv) cancer-based genetic screening, i.e., testing individuals with BRCA-related cancers. Currently BRCA1/2 population-based screening represents good value for the money among Ashkenazi Jews only. FH-based screening is potentially very cost-effective, although further studies that include costs of identifying high-risk women are needed. There is no evidence of cost-effectiveness for BRCA screening of all newly diagnosed cases of breast/ovarian cancers followed by cascade testing of relatives, but programs that include tools for identifying affected women at higher risk for inherited forms are promising. Cost-effectiveness is highly sensitive to the cost of BRCA1/2 testing.Genet Med 18 12, 1171-1180.

Sensitivity and specificity of a new automated system for the detection of hepatitis B virus, hepatitis C virus, and human immunodeficiency virus nucleic acid in blood and plasma donations.

PubMed

Galel, Susan A; Simon, Toby L; Williamson, Phillip C; AuBuchon, James P; Waxman, Dan A; Erickson, Yasuko; Bertuzis, Rasa; Duncan, John R; Malhotra, Khushbeer; Vaks, Jeffrey; Huynh, Nancy; Pate, Lisa Lee

2018-03-01

Use of nucleic acid testing (NAT) in donor infectious disease screening improves transfusion safety. Advances in NAT technology include improvements in assay sensitivity and system automation, and real-time viral target discrimination in multiplex assays. This article describes the sensitivity and specificity of cobas MPX, a multiplex assay for detection of human immunodeficiency virus (HIV)-1 Group M, HIV-2 and HIV-1 Group O RNA, HCV RNA, and HBV DNA, for use on the cobas 6800/8800 Systems. The specificity of cobas MPX was evaluated in samples from donors of blood and source plasma in the United States. Analytic sensitivity was determined with reference standards. Infectious window periods (WPs) before NAT detectability were calculated for current donor screening assays. The specificity of cobas MPX was 99.946% (99.883%-99.980%) in 11,203 blood donor samples tested individually (IDT), 100% (99.994%-100%) in 63,012 donor samples tested in pools of 6, and 99.994% (99.988%-99.998%) in 108,306 source plasma donations tested in pools of 96. Seven HCV NAT-yield donations and one seronegative occult HBV infection were detected. Ninety-five percent and 50% detection limits in plasma (IU/mL) were 25.7 and 3.8 for HIV-1M, 7.0 and 1.3 for HCV, and 1.4 and 0.3 for HBV. The HBV WP was 1 to 4 days shorter than other donor screening assays by IDT. cobas MPX demonstrated high specificity in blood and source plasma donations tested individually and in pools. High sensitivity, in particular for HBV, shortens the WP and may enhance detection of occult HBV. © 2017 The Authors Transfusion published by Wiley Periodicals, Inc. on behalf of AABB.

Urine tests for Down's syndrome screening.

PubMed

Alldred, S Kate; Guo, Boliang; Takwoingi, Yemisi; Pennant, Mary; Wisniewski, Susanna; Deeks, Jonathan J; Neilson, James P; Alfirevic, Zarko

2015-12-10

Down's syndrome occurs when a person has three copies of chromosome 21, or the specific area of chromosome 21 implicated in causing Down's syndrome, rather than two. It is the commonest congenital cause of mental disability and also leads to numerous metabolic and structural problems. It can be life-threatening, or lead to considerable ill health, although some individuals have only mild problems and can lead relatively normal lives. Having a baby with Down's syndrome is likely to have a significant impact on family life. The risk of a Down's syndrome affected pregnancy increases with advancing maternal age.Noninvasive screening based on biochemical analysis of maternal serum or urine, or fetal ultrasound measurements, allows estimates of the risk of a pregnancy being affected and provides information to guide decisions about definitive testing. Before agreeing to screening tests, parents need to be fully informed about the risks, benefits and possible consequences of such a test. This includes subsequent choices for further tests they may face, and the implications of both false positive and false negative screening tests (i.e. invasive diagnostic testing, and the possibility that a miscarried fetus may be chromosomally normal). The decisions that may be faced by expectant parents inevitably engender a high level of anxiety at all stages of the screening process, and the outcomes of screening can be associated with considerable physical and psychological morbidity. No screening test can predict the severity of problems a person with Down's syndrome will have. To estimate and compare the accuracy of first and second trimester urine markers for the detection of Down's syndrome. We carried out a sensitive and comprehensive literature search of MEDLINE (1980 to 25 August 2011), EMBASE (1980 to 25 August 2011), BIOSIS via EDINA (1985 to 25 August 2011), CINAHL via OVID (1982 to 25 August 2011), The Database of Abstracts of Reviews of Effectiveness (The Cochrane Library 2011, Issue 7), MEDION (25 August 2011), The Database of Systematic Reviews and Meta-Analyses in Laboratory Medicine (25 August 2011), The National Research Register (archived 2007), Health Services Research Projects in Progress database (25 August 2011). We studied reference lists and published review articles. Studies evaluating tests of maternal urine in women up to 24 weeks of gestation for Down's syndrome, compared with a reference standard, either chromosomal verification or macroscopic postnatal inspection. We extracted data as test positive or test negative results for Down's and non-Down's pregnancies allowing estimation of detection rates (sensitivity) and false positive rates (1-specificity). We performed quality assessment according to QUADAS (Quality Assessment of Diagnostic Accuracy Studies) criteria. We used hierarchical summary ROC (receiver operating characteristic) meta-analytical methods to analyse test performance and compare test accuracy. We performed analysis of studies allowing direct comparison between tests. We investigated the impact of maternal age on test performance in subgroup analyses. We included 19 studies involving 18,013 pregnancies (including 527 with Down's syndrome). Studies were generally of high quality, although differential verification was common with invasive testing of only high-risk pregnancies. Twenty-four test combinations were evaluated formed from combinations of the following seven different markers with and without maternal age: AFP (alpha-fetoprotein), ITA (invasive trophoblast antigen), ß-core fragment, free ßhCG (beta human chorionic gonadotrophin), total hCG, oestriol, gonadotropin peptide and various marker ratios. The strategies evaluated included three double tests and seven single tests in combination with maternal age, and one triple test, two double tests and 11 single tests without maternal age. Twelve of the 19 studies only evaluated the performance of a single test strategy while the remaining seven evaluated at least two test strategies. Two marker combinations were evaluated in more than four studies; second trimester ß-core fragment (six studies), and second trimester ß-core fragment with maternal age (five studies).In direct test comparisons, for a 5% false positive rate (FPR), the diagnostic accuracy of the double marker second trimester ß-core fragment and oestriol with maternal age test combination was significantly better (ratio of diagnostic odds ratio (RDOR): 2.2 (95% confidence interval (CI) 1.1 to 4.5), P = 0.02) (summary sensitivity of 73% (CI 57 to 85) at a cut-point of 5% FPR) than that of the single marker test strategy of second trimester ß-core fragment and maternal age (summary sensitivity of 56% (CI 45 to 66) at a cut-point of 5% FPR), but was not significantly better (RDOR: 1.5 (0.8 to 2.8), P = 0.21) than that of the second trimester ß-core fragment to oestriol ratio and maternal age test strategy (summary sensitivity of 71% (CI 51 to 86) at a cut-point of 5% FPR). Tests involving second trimester ß-core fragment and oestriol with maternal age are significantly more sensitive than the single marker second trimester ß-core fragment and maternal age, however, there were few studies. There is a paucity of evidence available to support the use of urine testing for Down's syndrome screening in clinical practice where alternatives are available.

Screening of Bangladeshi winter wheat (Triticum aestivum L.) cultivars for sensitivity to ozone

USDA-ARS?s Scientific Manuscript database

The sensitivity to ozone of ten Bangladeshi wheat cultivars was tested by exposing plants to eight ozone exposure regimes in controlled environment chambers. Visible leaf injury, dry weight, chlorophyll, carotenoid content, leaf greenness (SPAD value), quantum yield of photochemistry and stomatal re...

Validity of the Patient Health Questionnaire-9 to screen for depression in a high-HIV burden primary healthcare clinic in Johannesburg, South Africa.

PubMed

Cholera, R; Gaynes, B N; Pence, B W; Bassett, J; Qangule, N; Macphail, C; Bernhardt, S; Pettifor, A; Miller, W C

2014-01-01

Integration of depression screening into primary care may increase access to mental health services in sub-Saharan Africa, but this approach requires validated screening instruments. We sought to validate the Patient Health Questionnaire-9 (PHQ-9) as a depression screening tool at a high HIV-burden primary care clinic in Johannesburg, South Africa. We conducted a validation study of an interviewer-administered PHQ-9 among 397 patients. Sensitivity and specificity of the PHQ-9 were calculated with the Mini International Neuropsychiatric Interview (MINI) as the reference standard; receiver operating characteristic (ROC) curve analyses were performed. The prevalence of depression was 11.8%. One-third of participants tested positive for HIV. HIV-infected patients were more likely to be depressed (15%) than uninfected patients (9%; p=0.08). Using the standard cutoff score of ≥10, the PHQ-9 had a sensitivity of 78.7% (95% CI: 64.3-89.3) and specificity of 83.4% (95% CI: 79.1-87.2). The area under the ROC curve was 0.88 (95% CI: 0.83-0.92). Test performance did not vary by HIV status or language. In sensitivity analyses, reference test bias associated with the MINI appeared unlikely. We were unable to conduct qualitative work to adapt the PHQ-9 to this cultural context. This is the first validation study of the PHQ-9 in a primary care clinic in sub-Saharan Africa. It highlights the potential for using primary care as an access point for identifying depressive symptoms during routine HIV testing. The PHQ-9 showed reasonable accuracy in classifying cases of depression, was easily implemented by lay health workers, and is a useful screening tool in this setting. Copyright © 2014 Elsevier B.V. All rights reserved.

Screening for Cystic Fibrosis-Related Diabetes: Matching Pathophysiology and Addressing Current Challenges.

PubMed

Boudreau, Valérie; Reynaud, Quitterie; Dubois, Catherine Lehoux; Coriati, Adèle; Desjardins, Katherine; Durieu, Isabelle; Rabasa-Lhoret, Rémi

2016-10-01

Nearly 50% of adult patients with cystic fibrosis (CF) have diabetes. The occurrence of CF-related diabetes (CFRD) is preceded and is associated with deterioration of lung function and nutritional status. Microvascular complications can occur, but the main cause of death is respiratory failure rather than cardiovascular causes as in type 1 or type 2 diabetes. Because other methods such as glycated hemoglobin (A1C) levels are less sensitive in patients with CF, the recommended screening test is the oral glucose tolerance test (OGTT) with a 75 g glucose dose. However, OGTT is poorly suited for patients with CF, who are already facing a high disease-care burden, and appropriate CF-glucose cut-off for diagnosis and prognosis are also questioned. Thus, alternative screening methods are compared to the classical test (2-hour OGTT), including shorter OGTTs and continuous glucose monitoring. Moreover, many challenges complicate the screening for diabetes such as the complex medical care time for a patient, which is reflected by low adherence to screening tests. The best screening test should take into account the particularities of CFRD and the complexity of the CF medical care. Copyright © 2016 Canadian Diabetes Association. Published by Elsevier Inc. All rights reserved.

Jaw-opening force test to screen for Dysphagia: preliminary results.

PubMed

Hara, Koji; Tohara, Haruka; Wada, Satoko; Iida, Takatoshi; Ueda, Koichiro; Ansai, Toshihiro

2014-05-01

To assess the jaw-opening force test (JOFT) for dysphagia screening. Criterion standard. University dental hospital. Patients complaining of dysphagia (N=95) and with symptoms of dysphagia with chronic underlying causes (mean age ± SD, 79.3±9.61y; range, 50-94y; men: n=49; mean age ± SD, 77.03±9.81y; range, 50-94y; women: n=46; mean age ± SD, 75.42±9.73y; range, 51-93y) admitted for treatment between May 2011 and December 2012 were included. None. All patients were administered the JOFT and underwent fiberoptic endoscopic evaluation of swallowing (FEES). The mean jaw-opening strength was compared with aspiration (ASP) and pharyngeal residue observations of the FEES, which was used as the criterion standard. A receiver operating characteristic (ROC) curve analysis was performed. Forces of ≤3.2kg for men and ≤4kg for women were appropriate cutoff values for predicting ASP with a sensitivity and specificity of .57 and .79 for men and .93 and .52 for women, respectively. Based on the ROC analyses for predicting pharyngeal residue, forces of ≤5.3kg in men and ≤3.9kg in women were appropriate cutoff values, with a sensitivity and specificity of .80 and .88 for men and .83 and .81 for women, respectively. The JOFT could be a useful screening tool for predicting pharyngeal residue and could provide useful information to aid in the referral of patients for further diagnostic imaging testing. However, given its low sensitivity to ASP the JOFT should be paired with other screening tests that predict ASP. Copyright © 2014 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

Development of an algorithm for phenotypic screening of carbapenemase-producing Enterobacteriaceae in the routine laboratory.

PubMed

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.

Epistasis and the sensitivity of phenotypic screens for beta thalassaemia

PubMed Central

Penman, Bridget S; Gupta, Sunetra; Weatherall, David J

2015-01-01

Genetic disorders of haemoglobin, particularly the sickle cell diseases and the alpha and beta thalassaemias, are the commonest inherited disorders worldwide. The majority of affected births occur in low-income and lower-middle income countries. Screening programmes are a vital tool to counter these haemoglobinopathies by: (i) identifying individual carriers and allowing them to make informed reproductive choices, and (ii) generating population level gene-frequency estimates, to help ensure the optimal allocation of public health resources. For both of these functions it is vital that the screen performed is suitably sensitive. One popular first-stage screening option to detect carriers of beta thalassaemia in low-income countries is the One Tube Osmotic Fragility Test (OTOFT). Here we introduce a population genetic framework within which to quantify the likely sensitivity and specificity of the OTOFT in different epidemiological contexts. We demonstrate that interactions between the carrier states for beta thalassaemia and alpha thalassaemia, glucose-6-phosphate dehydrogenase deficiency and Southeast Asian Ovalocytosis have the potential to reduce the sensitivity of OTOFTs for beta thalassaemia heterozygosity to below 70%. Our results therefore caution against the widespread application of OTOFTs in regions where these erythrocyte variants co-occur. PMID:25521998

Glandular Lesions of the Cervix in Clinical Practice: A Cytology, Histology, and Human Papillomavirus Correlation Study From 2 Institutions.

PubMed

Miller, Ross A; Mody, Dina R; Tams, Kimberlee C; Thrall, Michael J

2015-11-01

The Papanicolaou (Pap) test has indisputably decreased cervical cancer mortality, as rates have declined by up to 80% in the United States since its implementation. However, the Pap test is considered less sensitive for detecting glandular lesions than for detecting those of squamous origin. Some studies have even suggested an increasing incidence of cervical adenocarcinoma, which may be a consequence of a relatively reduced ability to detect glandular lesions with cervical cancer screening techniques. To evaluate the detection rate of glandular lesions with screening techniques currently used for cervical cancer screening and to provide insight as to which techniques are most efficacious in our study population. We retrospectively reviewed any available cytology, human papillomavirus (HPV), and histologic malignancy data in patients diagnosed with adenocarcinoma in situ and adenocarcinoma from 2 geographically and socioeconomically disparate hospital systems. Identified patients having had a negative/unsatisfactory Pap test within 5 years of adenocarcinoma in situ or adenocarcinoma tissue diagnosis were considered Pap test screening failures. Patients with negative HPV tests on cytology samples were considered HPV screening failures. One hundred thirty cases were identified (age range, 22-93 years); 39 (30%) had no Pap history in our files. Eight of 91 remaining cases (8.8%) were screening failures. The detected sensitivity for identifying adenocarcinoma in situ/adenocarcinoma in this study was 91.2% by cytology alone and 92.3% when incorporating HPV testing. The most common cytologic diagnosis was atypical glandular cells (25 cases), and those diagnosed with adenocarcinoma were 7.4 years older than those diagnosed with adenocarcinoma in situ (50.3 versus 42.9 years). Nine of 24 HPV-tested cases (37.5%) were called atypical squamous cell of undetermined significance on cytology. Our results highlight the importance of combined Pap and HPV cotesting. Although the number of cases identified is relatively small, our data suggest screening for squamous lesions facilitates the recognition of glandular lesions in the cervix. Additionally, increased use of combined Pap and HPV cotesting may decrease detection failure rates with regard to glandular lesions.

High performance of a new PCR-based urine assay for HPV-DNA detection and genotyping.

PubMed

Tanzi, Elisabetta; Bianchi, Silvia; Fasolo, Maria Michela; Frati, Elena R; Mazza, Francesca; Martinelli, Marianna; Colzani, Daniela; Beretta, Rosangela; Zappa, Alessandra; Orlando, Giovanna

2013-01-01

Human papillomavirus (HPV) testing has been proposed as a means of replacing or supporting conventional cervical screening (Pap test). However, both methods require the collection of cervical samples. Urine sample is easier and more acceptable to collect and could be helpful in facilitating cervical cancer screening. The aim of this study was to evaluate the sensitivity and specificity of urine testing compared to conventional cervical smear testing using a PCR-based method with a new, designed specifically primer set. Paired cervical and first voided urine samples collected from 107 women infected with HIV were subjected to HPV-DNA detection and genotyping using a PCR-based assay and a restriction fragment length polymorphism method. Sensitivity, specificity, Positive Predictive Value (PPV), and Negative Predictive Value (NPV) were calculated using the McNemar's test for differences. Concordance between tests was assessed using the Cohen's unweighted Kappa (k). HPV DNA was detected in 64.5% (95% CI: 55.1-73.1%) of both cytobrush and urine samples. High concordance rates of HPV-DNA detection (k = 0.96; 95% CI: 0.90-1.0) and of high risk-clade and low-risk genotyping in paired samples (k = 0.80; 95% CI: 0.67-0.92 and k = 0.74; 95% CI: 0.60-0.88, respectively) were observed. HPV-DNA detection in urine versus cervix testing revealed a sensitivity of 98.6% (95% CI: 93.1-99.9%) and a specificity of 97.4% (95% CI: 87.7-99.9%), with a very high NPV (97.4%; 95% CI: 87.7-99.9%). The PCR-based assay utilized in this study proved highly sensitive and specific for HPV-DNA detection and genotyping in urine samples. These data suggest that a urine-based assay would be a suitable and effective tool for epidemiological surveillance and, most of all, screening programs. Copyright © 2012 Wiley Periodicals, Inc.

Which routine test for kidney function?

PubMed Central

Parkin, A; Smith, H C; Brocklebank, J T

1989-01-01

Eighty measurements of plasma creatinine concentration, height:creatinine ratio, and plasma beta 2 microglobulin concentration were made on 72 children (age 4 months-18.5 years) with known renal disease. Results were compared with simultaneous measurements of glomerular filtration rate using plasma clearance of 51Cr edetic acid to assess the performance of each test as an initial screening procedure of renal insufficiency. Height:creatinine index less than 2.1 was found to have a higher sensitivity and predictive value of a normal result than the other tests and is therefore the preferred test for a screening procedure. PMID:2510609

Airway physical examination tests for detection of difficult airway management in apparently normal adult patients.

PubMed

Roth, Dominik; Pace, Nathan L; Lee, Anna; Hovhannisyan, Karen; Warenits, Alexandra-Maria; Arrich, Jasmin; Herkner, Harald

2018-05-15

The unanticipated difficult airway is a potentially life-threatening event during anaesthesia or acute conditions. An unsuccessfully managed upper airway is associated with serious morbidity and mortality. Several bedside screening tests are used in clinical practice to identify those at high risk of difficult airway. Their accuracy and benefit however, remains unclear. The objective of this review was to characterize and compare the diagnostic accuracy of the Mallampati classification and other commonly used airway examination tests for assessing the physical status of the airway in adult patients with no apparent anatomical airway abnormalities. We performed this individually for each of the four descriptors of the difficult airway: difficult face mask ventilation, difficult laryngoscopy, difficult tracheal intubation, and failed intubation. We searched major electronic databases including CENTRAL, MEDLINE, Embase, ISI Web of Science, CINAHL, as well as regional, subject specific, and dissertation and theses databases from inception to 16 December 2016, without language restrictions. In addition, we searched the Science Citation Index and checked the references of all the relevant studies. We also handsearched selected journals, conference proceedings, and relevant guidelines. We updated this search in March 2018, but we have not yet incorporated these results. We considered full-text diagnostic test accuracy studies of any individual index test, or a combination of tests, against a reference standard. Participants were adults without obvious airway abnormalities, who were having laryngoscopy performed with a standard laryngoscope and the trachea intubated with a standard tracheal tube. Index tests included the Mallampati test, modified Mallampati test, Wilson risk score, thyromental distance, sternomental distance, mouth opening test, upper lip bite test, or any combination of these. The target condition was difficult airway, with one of the following reference standards: difficult face mask ventilation, difficult laryngoscopy, difficult tracheal intubation, and failed intubation. We performed screening and selection of the studies, data extraction and assessment of methodological quality (using QUADAS-2) independently and in duplicate. We designed a Microsoft Access database for data collection and used Review Manager 5 and R for data analysis. For each index test and each reference standard, we assessed sensitivity and specificity. We produced forest plots and summary receiver operating characteristic (ROC) plots to summarize the data. Where possible, we performed meta-analyses to calculate pooled estimates and compare test accuracy indirectly using bivariate models. We investigated heterogeneity and performed sensitivity analyses. We included 133 (127 cohort type and 6 case-control) studies involving 844,206 participants. We evaluated a total of seven different prespecified index tests in the 133 studies, as well as 69 non-prespecified, and 32 combinations. For the prespecified index tests, we found six studies for the Mallampati test, 105 for the modified Mallampati test, six for the Wilson risk score, 52 for thyromental distance, 18 for sternomental distance, 34 for the mouth opening test, and 30 for the upper lip bite test. Difficult face mask ventilation was the reference standard in seven studies, difficult laryngoscopy in 92 studies, difficult tracheal intubation in 50 studies, and failed intubation in two studies. Across all studies, we judged the risk of bias to be variable for the different domains; we mostly observed low risk of bias for patient selection, flow and timing, and unclear risk of bias for reference standard and index test. Applicability concerns were generally low for all domains. For difficult laryngoscopy, the summary sensitivity ranged from 0.22 (95% confidence interval (CI) 0.13 to 0.33; mouth opening test) to 0.67 (95% CI 0.45 to 0.83; upper lip bite test) and the summary specificity ranged from 0.80 (95% CI 0.74 to 0.85; modified Mallampati test) to 0.95 (95% CI 0.88 to 0.98; Wilson risk score). The upper lip bite test for diagnosing difficult laryngoscopy provided the highest sensitivity compared to the other tests (P < 0.001). For difficult tracheal intubation, summary sensitivity ranged from 0.24 (95% CI 0.12 to 0.43; thyromental distance) to 0.51 (95% CI 0.40 to 0.61; modified Mallampati test) and the summary specificity ranged from 0.87 (95% CI 0.82 to 0.91; modified Mallampati test) to 0.93 (0.87 to 0.96; mouth opening test). The modified Mallampati test had the highest sensitivity for diagnosing difficult tracheal intubation compared to the other tests (P < 0.001). For difficult face mask ventilation, we could only estimate summary sensitivity (0.17, 95% CI 0.06 to 0.39) and specificity (0.90, 95% CI 0.81 to 0.95) for the modified Mallampati test. Bedside airway examination tests, for assessing the physical status of the airway in adults with no apparent anatomical airway abnormalities, are designed as screening tests. Screening tests are expected to have high sensitivities. We found that all investigated index tests had relatively low sensitivities with high variability. In contrast, specificities were consistently and markedly higher than sensitivities across all tests. The standard bedside airway examination tests should be interpreted with caution, as they do not appear to be good screening tests. Among the tests we examined, the upper lip bite test showed the most favourable diagnostic test accuracy properties. Given the paucity of available data, future research is needed to develop tests with high sensitivities to make them useful, and to consider their use for screening difficult face mask ventilation and failed intubation. The 27 studies in 'Studies awaiting classification' may alter the conclusions of the review, once we have assessed them.

Validation of the Drug Abuse Screening Test (DAST-10): A study on illicit drug use among Chinese pregnant women.

PubMed

Lam, Lap Po; Leung, Wing Cheong; Ip, Patrick; Chow, Chun Bong; Chan, Mei Fung; Ng, Judy Wai Ying; Sing, Chu; Lam, Ying Hoo; Mak, Wing Lai Tony; Chow, Kam Ming; Chin, Robert Kien Howe

2015-06-19

We assessed the Chinese version of the Drug Abuse Screening Test (DAST-10) for identifying illicit drug use during pregnancy among Chinese population. Chinese pregnant women attending their first antenatal visit or their first unbooked visit to the maternity ward were recruited during a 4-month study period in 2011. The participants completed self-administered questionnaires on demographic information, a single question on illicit drug use during pregnancy and the DAST-10. Urine samples screened positive by the urine Point-of-Care Test were confirmed by gas chromatography-mass spectrometry. DAST-10 performance was compared with three different gold standards: urinalysis, self-reported drug use, and evidence of drug use by urinalysis or self-report. 1214 Chinese pregnant women participated in the study and 1085 complete DAST-10 forms were collected. Women who had used illicit drugs had significantly different DAST-10 scores than those who had not. The sensitivity of DAST-10 for identify illicit drug use in pregnant women ranged from 79.2% to 33.3% and specificity ranged from 67.7% to 99.7% using cut-off scores from ≥ 1 to ≥ 3. The ~ 80% sensitivity of DAST-10 using a cut-off score of ≥ 1 should be sufficient for screening of illicit drug use in Chinese pregnant women, but validation tests for drug use are needed.

Automated chest-radiography as a triage for Xpert testing in resource-constrained settings: a prospective study of diagnostic accuracy and costs

NASA Astrophysics Data System (ADS)

Philipsen, R. H. H. M.; Sánchez, C. I.; Maduskar, P.; Melendez, J.; Peters-Bax, L.; Peter, J. G.; Dawson, R.; Theron, G.; Dheda, K.; van Ginneken, B.

2015-07-01

Molecular tests hold great potential for tuberculosis (TB) diagnosis, but are costly, time consuming, and HIV-infected patients are often sputum scarce. Therefore, alternative approaches are needed. We evaluated automated digital chest radiography (ACR) as a rapid and cheap pre-screen test prior to Xpert MTB/RIF (Xpert). 388 suspected TB subjects underwent chest radiography, Xpert and sputum culture testing. Radiographs were analysed by computer software (CAD4TB) and specialist readers, and abnormality scores were allocated. A triage algorithm was simulated in which subjects with a score above a threshold underwent Xpert. We computed sensitivity, specificity, cost per screened subject (CSS), cost per notified TB case (CNTBC) and throughput for different diagnostic thresholds. 18.3% of subjects had culture positive TB. For Xpert alone, sensitivity was 78.9%, specificity 98.1%, CSS $13.09 and CNTBC $90.70. In a pre-screening setting where 40% of subjects would undergo Xpert, CSS decreased to $6.72 and CNTBC to $54.34, with eight TB cases missed and throughput increased from 45 to 113 patients/day. Specialists, on average, read 57% of radiographs as abnormal, reducing CSS ($8.95) and CNTBC ($64.84). ACR pre-screening could substantially reduce costs, and increase daily throughput with few TB cases missed. These data inform public health policy in resource-constrained settings.

Diagnostic accuracy of rapid urine dipstick test to predict urinary tract infection among pregnant women in Felege Hiwot Referral Hospital, Bahir Dar, North West Ethiopia.

PubMed

Demilie, Tazebew; Beyene, Getenet; Melaku, Selabat; Tsegaye, Wondewosen

2014-07-29

Untreated bacteriuria during pregnancy has been shown to be associated with low birth-weight and premature delivery. Therefore, routine screening for bacteriuria is advocated. The decision about how to screen pregnant women for bacteriuria has always been a balance between the cost of screening versus the sensitivity and specificity. This study was designed to evaluate the diagnostic accuracy of the rapid dipstick test to predict urinary tract infection in pregnancy against the gold standard urine culture. A total of 367 mid stream urine samples were collected, inoculated on MacConkey, Manitol salt agar (MSA) and blood agar and incubated aerobically at 37°C for overnight. Specimens were classified as "positive" for urinary tract infection (UTI) if the growth of the pathogen(s) was at a count ≥ 10(5) colony-forming units per milliliter (cfu/mL) of urine and classified as "negative" with growth of <10(5) cfu/mL. Urine samples were tested for the presence of nitrite and leukocyte esterase using dipstick rapid test in accordance to the manufacturer's instructions. From the total study participants, 37 pregnant women were symptomatic and the remaining 330 pregnant women were asymptomatic. The sensitivity and specificity of dipstick tests of leukocyte esterase was 50% and 89.1% for pregnant women with asymptomatic UTI(ABU) and 71.4% and 86.7% for symptomatic UTI respectively and for nitrite 35.7% and 98.0% for ABU and 57.1% and 96.7% symptomatic UTI. This study revealed that the use of dipstick leukocyte esterase and nitrite for screening UTI particularly asymptomatic bacteriuria was associated with many false positive and negative results when it was compared against the gold standard culture method. The low sensitivity and positive predictive value of urine dipstick test proved that culture should be used for the diagnosis of UTI.

Mobile HIV screening in Cape Town, South Africa: clinical impact, cost and cost-effectiveness.

PubMed

Bassett, Ingrid V; Govindasamy, Darshini; Erlwanger, Alison S; Hyle, Emily P; Kranzer, Katharina; van Schaik, Nienke; Noubary, Farzad; Paltiel, A David; Wood, Robin; Walensky, Rochelle P; Losina, Elena; Bekker, Linda-Gail; Freedberg, Kenneth A

2014-01-01

Mobile HIV screening may facilitate early HIV diagnosis. Our objective was to examine the cost-effectiveness of adding a mobile screening unit to current medical facility-based HIV testing in Cape Town, South Africa. We used the Cost Effectiveness of Preventing AIDS Complications International (CEPAC-I) computer simulation model to evaluate two HIV screening strategies in Cape Town: 1) medical facility-based testing (the current standard of care) and 2) addition of a mobile HIV-testing unit intervention in the same community. Baseline input parameters were derived from a Cape Town-based mobile unit that tested 18,870 individuals over 2 years: prevalence of previously undiagnosed HIV (6.6%), mean CD4 count at diagnosis (males 423/µL, females 516/µL), CD4 count-dependent linkage to care rates (males 31%-58%, females 49%-58%), mobile unit intervention cost (includes acquisition, operation and HIV test costs, $29.30 per negative result and $31.30 per positive result). We conducted extensive sensitivity analyses to evaluate input uncertainty. Model outcomes included site of HIV diagnosis, life expectancy, medical costs, and the incremental cost-effectiveness ratio (ICER) of the intervention compared to medical facility-based testing. We considered the intervention to be "very cost-effective" when the ICER was less than South Africa's annual per capita Gross Domestic Product (GDP) ($8,200 in 2012). We projected that, with medical facility-based testing, the discounted (undiscounted) HIV-infected population life expectancy was 132.2 (197.7) months; this increased to 140.7 (211.7) months with the addition of the mobile unit. The ICER for the mobile unit was $2,400/year of life saved (YLS). Results were most sensitive to the previously undiagnosed HIV prevalence, linkage to care rates, and frequency of HIV testing at medical facilities. The addition of mobile HIV screening to current testing programs can improve survival and be very cost-effective in South Africa and other resource-limited settings, and should be a priority.

Performance Assessment of Internal Quality Control (IQC) Products in Blood Transfusion Compatibility Testing in China

PubMed Central

Li, Jing-Jing; Gao, Qi; Liu, Zhi-Dong; Kang, Qiong-Hua; Hou, Yi-Jun; Zhang, Luo-Chuan; Hu, Xiao-Mei; Li, Jie; Zhang, Juan

2015-01-01

Internal quality control (IQC) is a critical component of laboratory quality management, and IQC products can determine the reliability of testing results. In China, given the fact that most blood transfusion compatibility laboratories do not employ IQC products or do so minimally, there is a lack of uniform and standardized IQC methods. To explore the reliability of IQC products and methods, we studied 697 results from IQC samples in our laboratory from 2012 to 2014. The results showed that the sensitivity and specificity of the IQCs in anti-B testing were 100% and 99.7%, respectively. The sensitivity and specificity of the IQCs in forward blood typing, anti-A testing, irregular antibody screening, and cross-matching were all 100%. The reliability analysis indicated that 97% of anti-B testing results were at a 99% confidence level, and 99.9% of forward blood typing, anti-A testing, irregular antibody screening, and cross-matching results were at a 99% confidence level. Therefore, our IQC products and methods are highly sensitive, specific, and reliable. Our study paves the way for the establishment of a uniform and standardized IQC method for pre-transfusion compatibility testing in China and other parts of the world. PMID:26488582

Impact of confidence number on accuracy of the SureSight Vision Screener.

PubMed

2010-02-01

To assess the relation between the confidence number provided by the Welch Allyn SureSight Vision Screener and screening accuracy, and to determine whether repeated testing to achieve a higher confidence number improves screening accuracy in pre-school children. Lay and nurse screeners screened 1452 children enrolled in the Vision in Preschoolers (VIP) Phase II Study. All children also underwent a comprehensive eye examination. By using statistical comparison of proportions, we examined sensitivity and specificity for detecting any ocular condition targeted for detection in the VIP study and conditions grouped by severity and by type (amblyopia, strabismus, significant refractive error, and unexplained decreased visual acuity) among children who had confidence numbers < or =4 (retest necessary), 5 (retest if possible), > or =6 (acceptable). Among the 687 (47.3%) children who had repeated testing by either lay or nurse screeners because of a low confidence number (<6) for one or both eyes in the initial testing, the same analyses were also conducted to compare results between the initial reading and repeated test reading with the highest confidence number in the same child. These analyses were based on the failure criteria associated with 90% specificity for detecting any VIP condition in VIP Phase II. A lower confidence number category were associated with higher sensitivity (0.71, 0.65, and 0.59 for < or =4, 5, and > or =6, respectively, p = 0.04) but no statistical difference in specificity (0.85, 0.85, and 0.91, p = 0.07) of detecting any VIP-targeted condition. Children with any VIP-targeted condition were as likely to be detected using the initial confidence number reading as using the higher confidence number reading from repeated testing. A higher confidence number obtained during screening with the SureSight Vision Screener is not associated with better screening accuracy. Repeated testing to reach the manufacturer's recommended minimum value is not helpful in pre-school vision screening.

Detection of Cryptosporidium oocysts in fresh and frozen cattle faeces: comparison of three methods.

PubMed

Brook, E J; Christley, R M; French, N P; Hart, C A

2008-01-01

The aim of this study was to compare the performance of three commonly used screening tests for Cryptosporidium oocysts in fresh and frozen cattle faeces. Twenty-nine freshly voided faecal samples were collected from calves from three farms in the northwest of England. Three diagnostic tests for Cryptosporidium were carried out on each sample both before and after freezing - the modified Ziehl-Neelsen (MZN) and auramine phenol (APh) stains and a commercial enzyme immunoassay (EIA) kit, the ProSpecT Cryptosporidium Microplate assay (Remel, Lenexa, KS). Twelve samples were deemed positive by the reference standard (polymerase chain reaction, PCR). There were some discrepancies between the results of the screening tests and the levels of agreement were quantified. The sensitivity and specificity of each method was determined, with PCR as the gold standard. Sensitivity and specificity of the MZN stain was optimized when samples with fewer than two oocyst-like bodies were classified as negative. All three screening methods used were effective in detecting Cryptosporidium infection in both fresh and frozen calf faeces. This study has highlighted the value of determining characteristics of tests used for diagnosis and epidemiological studies.

Validity of a modified Parkinson's disease screening questionnaire in India: effects of literacy of participants and medical training of screeners and implications for screening efforts in developing countries.

PubMed

Sarangmath, Nagaraja; Rattihalli, Rohini; Ragothaman, Mona; Gopalkrishna, Gururaj; Doddaballapur, Subbakrishna; Louis, Elan D; Muthane, Uday B

2005-12-01

The prevalence of Parkinson's disease (PD) is low among Indians, except in the Parsis. Data for Indians come from studies using different screening tools and criteria to detect PD. An epidemiological study in India, which has nearly a billion people, more than 18 spoken languages, and varying levels of literacy, requires development and validation of a screening tool for PD. The objectives of this study are to (1) validate a modified version of a widely used screening questionnaire for PD to suit the needs of the Indian population; (2) compare the use of a nonmedical assistant (NMA) with the use of a medical person during screening; and (3) compare the effect of literacy of participants on the validity of the screening tool. The validity of the questionnaire was tested on 125 participants from a home for the elderly. NMAs of similar background and medical personnel administered the modified screening questionnaire. A movement disorder neurologist blind to the responses on the questionnaire, examined participants independently and diagnosed if participants had PD. The questionnaire was validated in the movement disorders clinic, on known PD patients and their family members without PD. In the movement disorders clinic, sensitivity and specificity of the questionnaire were 100% and 89%, respectively. Fifty-seven participants were included for analysis. The questionnaire had a higher sensitivity when NMAs (75%) rather than the medical personnel (61%) administered it, and its specificity was higher with the medical personnel (61%) than with NMAs (55% and 25%). The questionnaire had a higher specificity in literates than illiterates, whereas sensitivity varied considerably. The modified questionnaire translated in a local Indian language had reasonable sensitivity and can be used to screen individuals for PD in epidemiological studies in India. This questionnaire can be administered by NMAs to screen PD and this strategy would reduce manpower costs. Literacy may influence epidemiological estimates when screening PD.

Evaluation of RealStar Reverse Transcription–Polymerase Chain Reaction Kits for Filovirus Detection in the Laboratory and Field

PubMed Central

Rieger, Toni; Kerber, Romy; El Halas, Hussein; Pallasch, Elisa; Duraffour, Sophie; Günther, Stephan; Ölschläger, Stephan

2016-01-01

Background. Diagnosis of Ebola virus (EBOV) disease (EVD) requires laboratory testing. Methods. The RealStar Filovirus Screen reverse transcription–polymerase chain reaction (RT-PCR) kit and the derived RealStar Zaire Ebolavirus RT-PCR kit were validated using in vitro transcripts, supernatant of infected cell cultures, and clinical specimens from patients with EVD. Results. The Filovirus Screen kit detected EBOV, Sudan virus, Taï Forest virus, Bundibugyo virus, Reston virus, and Marburg virus and differentiated between the genera Ebolavirus and Marburgvirus. The amount of filovirus RNA that could be detected with a probability of 95% ranged from 11 to 67 RNA copies/reaction on a LightCycler 480 II. The Zaire Ebolavirus kit is based on the Filovirus Screen kit but was optimized for detection of EBOV. It has an improved signal-to-noise ratio at low EBOV RNA concentrations and is somewhat more sensitive than the Filovirus kit. Both kits show significantly lower analytical sensitivity on a SmartCycler II. Clinical evaluation revealed that the SmartCycler II, compared with other real-time PCR platforms, decreases the clinical sensitivity of the Filovirus Screen kit to diagnose EVD at an early stage. Conclusions. The Filovirus Screen kit detects all human-pathogenic filoviruses with good analytical sensitivity if performed on an appropriate real-time PCR platform. High analytical sensitivity is important for early diagnosis of EVD. PMID:27549586

UTILITY OF A SINGLE LATE-NIGHT PLASMA CORTISOL AND ACTH FOR THE DIAGNOSIS OF CUSHING SYNDROME.

PubMed

Jarial, Kush Dev Singh; Bhansali, Anil; Mukherjee, Kanchan K; Pal, Rimesh; Sharma, Akhilesh; Vashishtha, Rakesh K; Sukumar, Suja P; Sachdeva, Naresh; Walia, Rama

2018-02-01

To evaluate the diagnostic efficacy of various screening tests for the diagnosis of Cushing syndrome (CS). Thirty-five patients with CS and 16 patients of pseudo-CS were enrolled. Assessment of 24-h urinary free cortisol (UFC), late-night salivary cortisol (LNSC), overnight dexamethasone suppression test (ONDST), late-night plasma cortisol (LNPC), and adrenocorticotropic hormone (ACTH) on outpatient basis, and during sleep as well as in awake state after 48 hours of hospital admission. We found that 24-h UFC performed the best among the screening tests with sensitivity, specificity and areas under the curve (AUCs) of 96.0%, 99%, and 0.988, respectively, at a cut-off of 144.6 μg/24 h. A cut-off of 10.5 nmol/L for LNSC had sensitivity 85.7%, specificity 88.2%, and an AUC of 0.897. A cut-off of 412.4 nmol/L for LNPC on outpatient basis had sensitivity 88.2%, specificity 91.2%, and an AUC of 0.957. Cut-offs of 215 and 243.3 nmol/L for LNPC during sleep and awake states after acclimatization had sensitivity, specificity, and an AUC of 94.1%, 88.2%, and 0.958, respectively. An ONDST cut-off of 94.6 nmol/L provided sensitivity, specificity, and an AUC of 96.0%, 99.03% and 0.995, respectively. A cut-off of 30.3 pg/mL for late-night ACTH on outpatient basis had sensitivity 67.6%, specificity 99.9%, and an AUC 0.796.A cut-off of 22.6 pg/mL for ACTH during sleep state after acclimatization had sensitivity, specificity, and an AUC of 73.5%, 99.2%, and 0.827, respectively. UFC is the best screening test for CS. Furthermore, single measurements of LNPC and ACTH help to establish the diagnosis and ACTH dependency of CS in the majority of patients with CS. ACTH = adrenocorticotropic hormone AUC = area under the curve CRH = corticotropin-releasing hormone CS = Cushing syndrome ECLIA = electrochemiluminescence immuno-assay LDDST = low-dose dexamethasone suppression test LNPC = late-night plasma cortisol LNSC = late-night salivary cortisol ONDST = overnight dexamethasone suppression test RIA = radio-immuno assay UFC = urinary free cortisol.

Comparison of four methods to assess colostral IgG concentration in dairy cows.

PubMed

Chigerwe, Munashe; Tyler, Jeff W; Middleton, John R; Spain, James N; Dill, Jeffrey S; Steevens, Barry J

2008-09-01

To determine sensitivity and specificity of 4 methods to assess colostral IgG concentration in dairy cows and determine the optimal cutpoint for each method. Cross-sectional study. 160 Holstein dairy cows. 171 composite colostrum samples collected within 2 hours after parturition were used in the study. Test methods used to estimate colostral IgG concentration consisted of weight of the first milking, 2 hydrometers, and an electronic refractometer. Results of the test methods were compared with colostral IgG concentration determined by means of radial immunodiffusion. For each method, sensitivity and specificity for detecting colostral IgG concentration < 50 g/L were calculated across a range of potential cutpoints, and the optimal cutpoint for each test was selected to maximize sensitivity and specificity. At the optimal cutpoint for each method, sensitivity for weight of the first milking (0.42) was significantly lower than sensitivity for each of the other 3 methods (hydrometer 1, 0.75; hydrometer 2, 0.76; refractometer, 0.75), but no significant differences were identified among the other 3 methods with regard to sensitivity. Specificities at the optimal cutpoint were similar for all 4 methods. Results suggested that use of either hydrometer or the electronic refractometer was an acceptable method of screening colostrum for low IgG concentration; however, the manufacturer-defined scale for both hydrometers overestimated colostral IgG concentration. Use of weight of the first milking as a screening test to identify bovine colostrum with inadequate IgG concentration could not be justified because of the low sensitivity.

Physical Examination Has a Low Yield in Screening for Carpal Tunnel Syndrome

PubMed Central

Dale, Ann Marie; Descatha, Alexis; Coomes, Justin; Franzblau, Alfred; Evanoff, Bradley

2013-01-01

Background Physical examination is often used to screen workers for carpal tunnel syndrome (CTS). In a population of newly-hired workers, we evaluated the yield of such screening. Methods Our study population included 1108 newly-hired workers in diverse industries. Baseline data included a symptom questionnaire, physical exam, and bilateral nerve conduction testing of the median and ulnar nerves; individual results were not shared with the employer. We tested three outcomes: symptoms of CTS, abnormal median nerve conduction, and a case definition of CTS that required both symptoms and median neuropathy. Results Of the exam measures used, only Semmes-Weinstein sensory testing had a sensitivity value above 31%. Positive predictive values were low, and likelihood ratios were all under 5.0 for positive testing and over 0.2 for negative testing. Conclusion Physical examination maneuvers have a low yield for the diagnosis of CTS in workplace surveillance programs and in post-offer, pre-placement screening programs. PMID:21154516

Testing for cognitive function in animals in a regulatory context.

PubMed

Bushnell, Philip J

2015-01-01

Superior cognitive functions have allowed the human species to proliferate in a world of incredible biological diversity. Threats to these essential capacities cannot be ignored, and a strategy is needed to evaluate the hazard posed by exposure to chemical and other agents. Because people exposed to chemicals often complain about confusion and forgetfulness, it is commonly thought that cognitive functions should be sensitive indicators of adverse consequences of chemical exposure. For these reasons, complex tests of cognitive function have been developed and deployed in experimental animal laboratories for decades. However, the results of these tests are rarely used as points of departure for chemical risk assessments. Due to their high cost in time, animals, and equipment, the efficacy and utility of these tests need to be evaluated in relation to cheaper and faster whole-animal screening methods. This review examines evidence for the assertions that cognitive functions represent uniquely sensitive indicators of chemical exposure, and that animal models of these functions are necessary to detect and quantify the neurotoxicity of chemicals. Studies conducted since the early 1980s to compare these approaches to assess the neurotoxicity of chemicals are reviewed for both adult and perinatal exposures in experimental rodents. Forty-one studies of 35 chemicals were found that directly compared acute effects using complex tests (i.e., tests that require training animals) with acute effects using screening tests (i.e., tests that do not require training animals) in adult rodents. Complex tests detected effects of three substances (bitertanol, iso-amyl nitrite, and Pfiesteria toxin) that had no effect on screening tests; for an additional five chemicals (carbaryl, deltamethrin, methyl mercury, tetraethyl tin, and Isopar-C), complex tests identified effects at lower doses than did screening tests. Fewer comparable cases were found for developmental exposures: screening and complex tests were found to be equivalent for trimethyltin, n-propylthiouracil (PTU), and elemental mercury. Analysis of two studies yielded an inconclusive case for lead. Evidence for the insufficiency of screening tests was found for PCBs and inhaled ethanol, though it is not clear that the measured effects of these chemicals reflected cognitive deficits per se. Whether these benefits are worth the additional time and expense of conducting complex tests is a matter for discussion in the research and risk management communities. Published by Elsevier Inc.

Comparative Evaluation of Preliminary Screening Methods for Colorectal Cancer in a Mass Program.

PubMed

Ye, Ding; Huang, Qiuchi; Li, Qilong; Jiang, Xiyi; Mamat, Mayila; Tang, Mengling; Wang, Jianbing; Chen, Kun

2017-09-01

The fecal immunochemical test (FIT) has been widely used in preliminary screening for colorectal cancer (CRC). The high-risk factor questionnaire (HRFQ) and quantitative risk-assessment method (QRAM) are recommended for estimating the risk of CRC qualitatively and quantitatively in China. We aimed to prospectively compare the diagnostic values of CRC preliminary screening methods to identify which method is preferable as a screening strategy. Individuals aged 40-74 years old were enrolled in a mass CRC screening program from January 1, 2007 to December 31, 2014, in Jiashan County, Zhejiang Province, China. FIT of two stool specimens at 1-week intervals was performed by laboratory personnel and face-to-face interviews were conducted by trained investigators. Screening data in the program were linked to a CRC surveillance and registry system, and CRC cases reported in the system were regarded as true patients. A total of 96,043 subjects were included. The sensitivity and specificity of FIT for detecting CRC cases were 75.49% (95% CI 69.84-80.39) and 90.36% (95% CI 90.17-90.54), respectively. QRAM was more sensitive (p < 0.001) and less specific (p < 0.001) than HRFQ. The sensitivity and specificity of FIT along with HRFQ were 86.56% (95% CI 81.81-90.22) and 81.37% (95% CI 81.12-81.62), and those of FIT along with QRAM were 88.93% (95% CI 84.47-92.23) and 73.95% (95% CI 73.67-74.23). Our findings suggest that CRC preliminary screening with FIT and QRAM in parallel has high sensitivity and satisfactory specificity, and is a useful strategy in mass screening programs.

Prospective evaluation of 64 serum autoantibodies as biomarkers for early detection of colorectal cancer in a true screening setting.

PubMed

Chen, Hongda; Werner, Simone; Butt, Julia; Zörnig, Inka; Knebel, Phillip; Michel, Angelika; Eichmüller, Stefan B; Jäger, Dirk; Waterboer, Tim; Pawlita, Michael; Brenner, Hermann

2016-03-29

Novel blood-based screening tests are strongly desirable for early detection of colorectal cancer (CRC). We aimed to identify and evaluate autoantibodies against tumor-associated antigens as biomarkers for early detection of CRC. 380 clinically identified CRC patients and samples of participants with selected findings from a cohort of screening colonoscopy participants in 2005-2013 (N=6826) were included in this analysis. Sixty-four serum autoantibody markers were measured by multiplex bead-based serological assays. A two-step approach with selection of biomarkers in a training set, and validation of findings in a validation set, the latter exclusively including participants from the screening setting, was applied. Anti-MAGEA4 exhibited the highest sensitivity for detecting early stage CRC and advanced adenoma. Multi-marker combinations substantially increased sensitivity at the price of a moderate loss of specificity. Anti-TP53, anti-IMPDH2, anti-MDM2 and anti-MAGEA4 were consistently included in the best-performing 4-, 5-, and 6-marker combinations. This four-marker panel yielded a sensitivity of 26% (95% CI, 13-45%) for early stage CRC at a specificity of 90% (95% CI, 83-94%) in the validation set. Notably, it also detected 20% (95% CI, 13-29%) of advanced adenomas. Taken together, the identified biomarkers could contribute to the development of a useful multi-marker blood-based test for CRC early detection.

[Psychometric properties and diagnostic value of 'lexical screening for aphasias'].

PubMed

Pena-Chavez, R; Martinez-Jimenez, L; Lopez-Espinoza, M

2014-09-16

INTRODUCTION. Language assessment in persons with brain injury makes it possible to know whether they require language rehabilitation or not. Given the importance of a precise evaluation, assessment instruments must be valid and reliable, so as to avoid mistaken and subjective diagnoses. AIM. To validate 'lexical screening for aphasias' in a sample of 58 Chilean individuals. SUBJECTS AND METHODS. A screening-type language test, lasting 20 minutes and based on the lexical processing model devised by Patterson and Shewell (1987), was constructed. The sample was made up of two groups containing 29 aphasic subjects and 29 control subjects from different health centres in the regions of Biobio and Maule, Chile. Their ages ranged between 24 and 79 years and had between 0 and 17 years' schooling. Tests were carried out to determine discriminating validity, concurrent validity with the aphasia disorder assessment battery, reliability, sensitivity and specificity. RESULTS. The statistical analysis showed a high discriminating validity (p < 0.001), an acceptable mean concurrent validity with aphasia disorder assessment battery (rs = 0.65), high mean reliability (alpha = 0.87), moderate mean sensitivity (69%) and high mean specificity (86%). CONCLUSION. 'Lexical screening for aphasias' is valid and reliable for assessing language in persons with aphasias; it is sensitive for detecting aphasic subjects and is specific for precluding language disorders in persons with normal language abilities.

Using micropower impulse radar technology to screen for pneumothorax: an international bi-institutional study.

PubMed

van der Wilden, Gwendolyn M; Van der Wilden, Gwen; Albers, Christoph E; Albers, Christof; Haefeli, Pascal C; Haefeli, Peter; Zimmermann, Heinz; Zimmerman, Heinz; Exadaktylos, Aristomenis; Exadaktylos, Aris; Levy, Phillip; Birkhan, Oscar; Birkham, Oscar; Michaildou, Maria; Michailidou, Maria; Sideris, Antonios; Velmahos, George C; Velmahos, George; Alam, Hasan B; Alam, Hasan; King, David R; King, David; Fagenholz, Peter J; Fagenholz, Peter; Yeh, D Dante; Yeh, Dante; de Moya, Marc A

2012-12-01

Pneumothoraces (PTXs) are a common entity in thoracic trauma. Micropower impulse radar (MIR) has been able to detect PTXs in surgical patients. However, this technology has not been tested previously on trauma patients. The purpose of this study was to determine the sensitivity and specificity of MIR to detect clinically significant PTXs. We hypothesized that MIR technology can effectively screen trauma patients for clinically significant PTXs. This was a prospective observational study in Level I trauma centers in Boston, Massachusetts, and Bern, Switzerland. All trauma patients undergoing a chest computed tomographic (CT) scan were eligible for the study. Consent was obtained, and readings were performed within 30 minutes before or after the CT scan. The patients had eight lung fields tested (four on each side). The qualitative and quantitative MIR results were blinded and stored on the device. We then compared the results of the MIR to the CT scan and the need for chest tube drainage. We defined PTXs as clinically significant if they required a chest tube. Seventy-five patients were enrolled, with a mean age of 46 ± 16 years. Eighty-four percent were male. The screening test took approximately 1 minute. All but two patients had blunt chest trauma. Six true-positives, 6 false-positives, 63 true-negatives, and 0 false-negatives resulted in an overall sensitivity of 100%. MIR is an easy to use handheld technology that effectively screened patients for clinically significant PTXs, with a sensitivity and negative predictive value of 100%. MIR may be used for rapid, repeatable, and ongoing surveillance of trauma patients. Diagnostic study, level III.

Identifying DNA Methylation Biomarkers for Non-Endoscopic Detection of Barrett’s Esophagus

PubMed Central

Moinova, Helen R.; LaFramboise, Thomas; Lutterbaugh, James D.; Chandar, Apoorva Krishna; Dumot, John; Faulx, Ashley; Brock, Wendy; De la Cruz Cabrera, Omar; Guda, Kishore; Barnholtz-Sloan, Jill S.; Iyer, Prasad G.; Canto, Marcia I.; Wang, Jean S.; Shaheen, Nicholas J.; Thota, Prashanti N.; Willis, Joseph E.; Chak, Amitabh; Markowitz, Sanford D.

2018-01-01

We report a biomarker-based non-endoscopic method for detecting Barrett’s esophagus (BE), based on detecting methylated DNAs retrieved via a swallowable balloon-based esophageal sampling device. BE is the precursor of, and a major recognized risk factor for, developing esophageal adenocarcinoma (EAC). Endoscopy, the current standard for BE detection, is not cost-effective for population screening. We performed genome-wide screening to ascertain regions targeted for recurrent aberrant cytosine methylation in BE, identifying high-frequency methylation within the CCNA1 locus. We tested CCNA1 DNA methylation as a BE biomarker in cytology brushings of the distal esophagus from 173 individuals with or without BE. CCNA1 DNA methylation demonstrated an area under the curve (AUC)=0.95 for discriminating BE-related metaplasia and neoplasia cases versus normal individuals, performing identically to methylation of VIM DNA, an established BE biomarker. When combined, the resulting two biomarker panel was 95% sensitive and 91% specific. These results were replicated in an independent validation cohort of 149 individuals, who were assayed using the same cutoff values for test positivity established in the training population. To progress toward non-endoscopic esophageal screening, we engineered a well-tolerated, swallowable, encapsulated balloon device able to selectively sample the distal esophagus within 5 minutes. In balloon samples from 86 individuals, tests of CCNA1 plus VIM DNA methylation detected BE metaplasia with 90.3% sensitivity and 91.7% specificity. Combining the balloon sampling device with molecular assays of CCNA1 plus VIM DNA methylation enables an efficient, well-tolerated, sensitive, and specific method of screening at-risk populations for BE. PMID:29343623

Strategies to Identify the Lynch Syndrome Among Patients With Colorectal Cancer

PubMed Central

Ladabaum, Uri; Wang, Grace; Terdiman, Jonathan; Blanco, Amie; Kuppermann, Miriam; Boland, C. Richard; Ford, James; Elkin, Elena; Phillips, Kathryn A.

2013-01-01

Background Testing has been advocated for all persons with newly diagnosed colorectal cancer to identify families with the Lynch syndrome, an autosomal dominant cancer-predisposition syndrome that is a paradigm for personalized medicine. Objective To estimate the effectiveness and cost-effectiveness of strategies to identify the Lynch syndrome, with attention to sex, age at screening, and differential effects for probands and relatives. Design Markov model that incorporated risk for colorectal, endometrial, and ovarian cancers. Data Sources Published literature. Target Population All persons with newly diagnosed colorectal cancer and their relatives. Time Horizon Lifetime. Perspective Third-party payer. Intervention Strategies based on clinical criteria, prediction algorithms, tumor testing, or up-front germline mutation testing, followed by tailored screening and risk-reducing surgery. Outcome Measures Life-years, cancer cases and deaths, costs, and incremental cost-effectiveness ratios. Results of Base-Case Analysis The benefit of all strategies accrued primarily to relatives with a mutation associated with the Lynch syndrome, particularly women, whose life expectancy could increase by approximately 4 years with hysterectomy and salpingo-oophorectomy and adherence to colorectal cancer screening recommendations. At current rates of germline testing, screening, and prophylactic surgery, the strategies reduced deaths from colorectal cancer by 7% to 42% and deaths from endometrial and ovarian cancer by 1% to 6%. Among tumor-testing strategies, immunohistochemistry followed by BRAF mutation testing was preferred, with an incremental cost-effectiveness ratio of $36 200 per life-year gained. Results of Sensitivity Analysis The number of relatives tested per proband was a critical determinant of both effectiveness and cost-effectiveness, with testing of 3 to 4 relatives required for most strategies to meet a threshold of $50 000 per life-year gained. Immunohistochemistry followed by BRAF mutation testing was preferred in 59% of iterations in probabilistic sensitivity analysis at a threshold of $100 000 per life-year gained. Screening for the Lynch syndrome with immunohistochemistry followed by BRAF mutation testing only up to age 70 years cost $44 000 per incremental life-year gained compared with screening only up to age 60 years, and screening without an upper age limit cost $88 700 per incremental life-year gained compared with screening only up to age 70 years. Limitation Other types of cancer, uncertain family pedigrees, and genetic variants of unknown significance were not considered. Conclusion Widespread colorectal tumor testing to identify families with the Lynch syndrome could yield substantial benefits at acceptable costs, particularly for women with a mutation associated with the Lynch syndrome who begin regular screening and have risk-reducing surgery. The cost-effectiveness of such testing depends on the participation rate among relatives at risk for the Lynch syndrome. Primary Funding Source National Institutes of Health. PMID:21768580

Some performance effects of age and low blood alcohol levels on a computerized neuropsychological test.

DOT National Transportation Integrated Search

1995-02-01

COGSCREEN is a computerized test battery developed for the Federal Aviation Administration as an airman neuropsychological screening instrument for cognitive functioning. This study explored a multifaceted application of the sensitivity of the batter...

Rapid assessment of Schistosoma mansoni: the validity, applicability and cost-effectiveness of the Lot Quality Assurance Sampling method in Uganda

PubMed Central

Brooker, Simon; Kabatereine, Narcis B.; Myatt, Mark; Stothard, J. Russell; Fenwick, Alan

2007-01-01

Summary Rapid and accurate identification of communities at highest risk of morbidity from schistosomiasis is key for sustainable control. Although school questionnaires can effectively and inexpensively identify communities with a high prevalence of Schistosoma haematobium, parasitological screening remains the preferred option for S. mansoni. To help reduce screening costs, we investigated the validity of Lot Quality Assurance Sampling (LQAS) in classifying schools according categories of S. mansoni prevalence in Uganda, and explored its applicability and cost-effectiveness. First, we evaluated several sampling plans using computer simulation and then field tested one sampling plan in 34 schools in Uganda. Finally, cost-effectiveness of different screening and control strategies (including mass treatment without prior screening) was determined, and sensitivity analysis undertaken to assess the effect of infection levels and treatment costs. In identifying schools with prevalence ≥50%, computer simulations showed that LQAS had high levels of sensitivity and specificity (>90%) at sample sizes <20. The method also provides an ability to classify communities into three prevalence categories. Field testing showed that LQAS where 15 children were sampled had excellent diagnostic performance (sensitivity: 100%, specificity: 96.4%, positive predictive value: 85.7% and negative predictive value: 92.3%). Screening using LQAS was more cost-effective than mass treating all schools (US$ 218 vs. US$ 482 / high prevalence school treated). Threshold analysis indicated that parasitological screening and mass treatment would become equivalent for settings where prevalence exceeds 50% in 75% of schools and for treatment costs of US$ 0.19 per schoolchild. We conclude that, in Uganda, LQAS provides a rapid, valid, and cost-effective method for guiding decision makers in allocating finite resources for the control of schistosomiasis. PMID:15960703

Rapid assessment of Schistosoma mansoni: the validity, applicability and cost-effectiveness of the Lot Quality Assurance Sampling method in Uganda.

PubMed

Brooker, Simon; Kabatereine, Narcis B; Myatt, Mark; Russell Stothard, J; Fenwick, Alan

2005-07-01

Rapid and accurate identification of communities at highest risk of morbidity from schistosomiasis is key for sustainable control. Although school questionnaires can effectively and inexpensively identify communities with a high prevalence of Schistosoma haematobium, parasitological screening remains the preferred option for S. mansoni. To help reduce screening costs, we investigated the validity of Lot Quality Assurance Sampling (LQAS) in classifying schools according to categories of S. mansoni prevalence in Uganda, and explored its applicability and cost-effectiveness. First, we evaluated several sampling plans using computer simulation and then field tested one sampling plan in 34 schools in Uganda. Finally, cost-effectiveness of different screening and control strategies (including mass treatment without prior screening) was determined, and sensitivity analysis undertaken to assess the effect of infection levels and treatment costs. In identifying schools with prevalences > or =50%, computer simulations showed that LQAS had high levels of sensitivity and specificity (>90%) at sample sizes <20. The method also provides an ability to classify communities into three prevalence categories. Field testing showed that LQAS where 15 children were sampled had excellent diagnostic performance (sensitivity: 100%, specificity: 96.4%, positive predictive value: 85.7% and negative predictive value: 92.3%). Screening using LQAS was more cost-effective than mass treating all schools (US$218 vs. US$482/high prevalence school treated). Threshold analysis indicated that parasitological screening and mass treatment would become equivalent for settings where prevalence > or =50% in 75% of schools and for treatment costs of US$0.19 per schoolchild. We conclude that, in Uganda, LQAS provides a rapid, valid and cost-effective method for guiding decision makers in allocating finite resources for the control of schistosomiasis.

ASSESSMENT OF DE-71, A COMMERCIAL POLYBROMINATED DIPHENYL ETHER (PBDE) MIXTURE, IN THE EDSP MALE AND FEMALE PUBERTAL PROTOCOLS

EPA Science Inventory

DE-71, a commercial mixture, was used to test the sensitivity of the female and male pubertal protocol to detect thyroid active chemicals. These protocols are being evaluated for the U.S. EPA's Endocrine Disruptor Screening Program as part of a Tier I Screening Battery. To exa...

Hearing loss in the developing world: evaluating the iPhone mobile device as a screening tool.

PubMed

Peer, S; Fagan, J J

2015-01-01

Developing countries have the world's highest prevalence of hearing loss, and hearing screening programmes are scarce. Mobile devices such as smartphones have potential for audiometric testing. To evaluate the uHear app using an Apple iPhone as a possible hearing screening tool in the developing world, and to determine accuracy of certain hearing thresholds that could prove useful in early detection of hearing loss for high-risk populations in resource-poor communities. This was a quasi-experimental study design. Participants recruited from the Otolaryngology Clinic, Groote Schuur Hospital, Cape Town, South Africa, completed a uHear test in three settings--waiting room (WR), quiet roon (QR) and soundproof room (SR). Thresholds were compared with formal audiograms. Twenty-five patients were tested (50 ears). The uHear test detected moderate or worse hearing loss (pure-tone average (PTA) > 40 dB accurately with a sensitivity of 100% in all three environments. Specificity was 88% (SR), 73% (QR) and 68% (WR). Its was highly accurate in detecting high-frequency hearing loss (2 000, 4 000, 6 000 Hz) in the QR and SR with 'good' and 'very good' kappa values, showing statistical significance (p < 0.05). It was moderately accurate in low-frequency hearing loss (250, 500, 1 000 Hz) in the SR, and poor in the QR and WR. Using the iPhone, uHear is a feasible screening test to rule out significant hearing loss (PTA > 40 dB). It is highly sensitive for detecting threshold changes at high frequencies, making it reasonably well suited to detect presbycusis and ototoxic hearing loss from HIV, tuberculosis therapy and chemotherapy. Portability and ease of use make it appropriate to use in developing world communities that lack screening programmes.

NON-INVASIVE MONITORING OF FOETAL ANAEMIA IN KELL SENSITIZED PREGNANCY.

PubMed

Memon, Zaibunnisa; Sheikh, Sana Sadiq

2015-01-01

We report a case of Kell sensitized pregnancy with good neonatal outcome. Anti-K antibodies were detected in maternal serum in early pregnancy as a part of routine antibody screening test. The middle cerebral artery doppler monitoring and serial titers were carried out to screen for foetal anaemia. Despite of rising antibody titers, serial middle cerebral artery doppler was normal and did not showed foetal anaemia. The pregnancy was carried out till term and patient delivered at 37 weeks of pregnancy with no evidence of foetal anaemia. This case underlines the need of general screening on rare antibodies in all pregnant women and that non-invasive monitoring of foetal anaemia can be done with anti-k titers and middle cerebral artery Doppler.

Effectiveness of the "Timed Up and Go" (TUG) and the Chair test as screening tools for geriatric fall risk assessment in the ED.

PubMed

Chow, Richard B; Lee, Andre; Kane, Bryan G; Jacoby, Jeanne L; Barraco, Robert D; Dusza, Stephen W; Meyers, Matthew C; Greenberg, Marna Rayl

2018-06-07

We sought to evaluate the effectiveness of the "Timed Up and Go" (TUG) and the Chair test as screening tools in the Emergency Department (ED), stratified by sex. This prospective cohort study was conducted at a Level 1 Trauma center. After consent, subjects performed the TUG and the Chair test. Subjects were contacted for phone follow-up and asked to self-report interim falling. Data from 192 subjects were analyzed. At baseline, 71.4% (n = 137) screened positive for increased falls risk based on the TUG evaluation, and 77.1% (n = 148) scored below average on the Chair test. There were no differences by patient sex. By the six-month evaluation 51 (26.6%) study participants reported at least one fall. Females reported a non-significant higher prevalence of falls compared to males (29.7% versus 22.2%, p = 0.24). TUG test had a sensitivity of 70.6% (95% CI: 56.2%-82.5%), a specificity of 28.4% (95% CI: 21.1%-36.6%), a positive predictive (PP) value 26.3% (95% CI: 19.1%-34.5%) and a negative predictive (NP) value of 72.7% (95% CI: 59.0%-83.9%). Similar results were observed with the Chair test. It had a sensitivity of 78.4% (95% CI: 64.7%-88.7%), a specificity of 23.4% (95% CI: 16.7%-31.3%), a PP value 27.0% (95% CI: 20.1%-34.9%) and a NP value of 75.0% (95% CI: 59.7%-86.8%). No significant differences were observed between sexes. There were no sex specific significant differences in TUG or Chair test screening performance. Neither test performed well as a screening tool for future falls in the elderly in the ED setting. Copyright © 2018 Elsevier Inc. All rights reserved.

The sensitivity and specificity of Lassa virus IgM by ELISA as screening tool at early phase of Lassa fever infection

PubMed Central

Ibekwe, Titus S.; Nwegbu, Maxwell M.; Asogun, Daniel; Adomeh, Donatus I.; Okokhere, Peter O.

2012-01-01

Background: Early diagnosis, prompt treatment, and disease containment are vital measures in the management of Lassa fever (LF), a lethal and contagious arenaviral hemorrhagic disease prevalent in West Africa. Lassa Virus (LAV)-specific Reverse Transcriptase Polymerase Chain Reaction (RT-PCR) test, the gold standard for diagnosis, is unavailable in most centers. Serologic detection of LAV IgM is a more accessible tool and this work was to investigate its adequacy as an early marker for LF. Patients and Methods: A prospective case–control study conducted July 2007-March 2011 in a tertiary referral health center in Nigeria. Blood samples for test and control were evaluated for Lassa specific antigens and IgM using RT-PCR (primers S36+ and LVS 339) and indirect ELISA (Lassa Nucleo-protein (NP)-Antigen) respectively. RT-PCR outcome was used as standard to test for the sensitivity and specificity of IgM. Results: Of the 37 confirmed cases of LF infection by RT-PCR, 21 (57%) were IgM positive. Amongst the 35 confirmed negative cases (control group), eight were IgM positive. The diagnostic sensitivity and specificity of the IgM assay were 57% and 77% respectively. The negative and positive predictive values of the IgM serological assay were 63% and 72%, respectively, while the efficiency of the test was 67%. Conclusion: The specificity and sensitivity of IgM as a screening tool for early detection of LF appear weak and, hence, the need for a reliable LF “rapid screening kit” since RT-PCR is unavailable in most centers. In the interim, “high clinical index of suspicion,” irrespective of IgM status, requires urgent referral to confirmatory centers. PMID:23661877

The sensitivity and specificity of Lassa virus IgM by ELISA as screening tool at early phase of Lassa fever infection.

PubMed

Ibekwe, Titus S; Nwegbu, Maxwell M; Asogun, Daniel; Adomeh, Donatus I; Okokhere, Peter O

2012-10-01

Early diagnosis, prompt treatment, and disease containment are vital measures in the management of Lassa fever (LF), a lethal and contagious arenaviral hemorrhagic disease prevalent in West Africa. Lassa Virus (LAV)-specific Reverse Transcriptase Polymerase Chain Reaction (RT-PCR) test, the gold standard for diagnosis, is unavailable in most centers. Serologic detection of LAV IgM is a more accessible tool and this work was to investigate its adequacy as an early marker for LF. A prospective case-control study conducted July 2007-March 2011 in a tertiary referral health center in Nigeria. Blood samples for test and control were evaluated for Lassa specific antigens and IgM using RT-PCR (primers S36+ and LVS 339) and indirect ELISA (Lassa Nucleo-protein (NP)-Antigen) respectively. RT-PCR outcome was used as standard to test for the sensitivity and specificity of IgM. Of the 37 confirmed cases of LF infection by RT-PCR, 21 (57%) were IgM positive. Amongst the 35 confirmed negative cases (control group), eight were IgM positive. The diagnostic sensitivity and specificity of the IgM assay were 57% and 77% respectively. The negative and positive predictive values of the IgM serological assay were 63% and 72%, respectively, while the efficiency of the test was 67%. The specificity and sensitivity of IgM as a screening tool for early detection of LF appear weak and, hence, the need for a reliable LF "rapid screening kit" since RT-PCR is unavailable in most centers. In the interim, "high clinical index of suspicion," irrespective of IgM status, requires urgent referral to confirmatory centers.

Parkinson's and Alzheimer's diseases in Costa Rica: a feasibility study toward a national screening program

PubMed Central

Wesseling, Catharina; Román, Norbel; Quirós, Indiana; Páez, Laura; García, Vilma; María Mora, Ana; Juncos, Jorge L.; Steenland, Kyle N.

2013-01-01

Background The integration of mental and neurologic services in healthcare is a global priority. The universal Social Security of Costa Rica aspires to develop national screening of neurodegenerative disorders among the elderly, as part of the non-communicable disease agenda. Objective This study assessed the feasibility of routine screening for Parkinson's disease (PD) and Alzheimer's disease (AD) within the public healthcare system of Costa Rica. Design The population (aged ≥65) in the catchment areas of two primary healthcare clinics was targeted for motor and cognitive screening during routine annual health check-ups. The screening followed a tiered three-step approach, with increasing specificity. Step 1 involved a two-symptom questionnaire (tremor-at-rest; balance) and a spiral drawing test for motor assessment, as well as a three-word recall and animal category fluency test for cognitive assessment. Step 2 (for those failing Step 1) was a 10-item version of the Unified Parkinson Disease Rating Scale and the Mini-Mental State Examination. Step 3 (for those failing Step 2) was a comprehensive neurologic exam with definitive diagnosis of PD, AD, mild cognitive impairment (MCI), other disorders, or subjects who were healthy. Screening parameters and disease prevalence were calculated. Results Of the 401 screened subjects (80% of target population), 370 (92%), 163 (45%), and 81 (56%) failed in Step 1, Step 2, and Step 3, respectively. Thirty-three, 20, and 35 patients were diagnosed with PD, AD, and MCI, respectively (7 were PD with MCI/AD); 90% were new cases. Step 1 sensitivities of motor and cognitive assessments regarding Step 2 were both 93%, and Step 2 sensitivities regarding definitive diagnosis 100 and 96%, respectively. Specificities for Step 1 motor and cognitive tests were low (23% and 29%, respectively) and for Step 2 tests acceptable (76%, 94%). Based on international data, PD prevalence was 3.7 times higher than expected; AD prevalence was as expected. Conclusion Proposed protocol adjustments will increase test specificity and reduce administration time. A routine screening program is feasible within the public healthcare system of Costa Rica. PMID:24378195

Parkinson's and Alzheimer's diseases in Costa Rica: a feasibility study toward a national screening program.

PubMed

Wesseling, Catharina; Román, Norbel; Quirós, Indiana; Páez, Laura; García, Vilma; Mora, Ana María; Juncos, Jorge L; Steenland, Kyle N

2013-12-27

The integration of mental and neurologic services in healthcare is a global priority. The universal Social Security of Costa Rica aspires to develop national screening of neurodegenerative disorders among the elderly, as part of the non-communicable disease agenda. This study assessed the feasibility of routine screening for Parkinson's disease (PD) and Alzheimer's disease (AD) within the public healthcare system of Costa Rica. The population (aged ≥65) in the catchment areas of two primary healthcare clinics was targeted for motor and cognitive screening during routine annual health check-ups. The screening followed a tiered three-step approach, with increasing specificity. Step 1 involved a two-symptom questionnaire (tremor-at-rest; balance) and a spiral drawing test for motor assessment, as well as a three-word recall and animal category fluency test for cognitive assessment. Step 2 (for those failing Step 1) was a 10-item version of the Unified Parkinson Disease Rating Scale and the Mini-Mental State Examination. Step 3 (for those failing Step 2) was a comprehensive neurologic exam with definitive diagnosis of PD, AD, mild cognitive impairment (MCI), other disorders, or subjects who were healthy. Screening parameters and disease prevalence were calculated. Of the 401 screened subjects (80% of target population), 370 (92%), 163 (45%), and 81 (56%) failed in Step 1, Step 2, and Step 3, respectively. Thirty-three, 20, and 35 patients were diagnosed with PD, AD, and MCI, respectively (7 were PD with MCI/AD); 90% were new cases. Step 1 sensitivities of motor and cognitive assessments regarding Step 2 were both 93%, and Step 2 sensitivities regarding definitive diagnosis 100 and 96%, respectively. Specificities for Step 1 motor and cognitive tests were low (23% and 29%, respectively) and for Step 2 tests acceptable (76%, 94%). Based on international data, PD prevalence was 3.7 times higher than expected; AD prevalence was as expected. Proposed protocol adjustments will increase test specificity and reduce administration time. A routine screening program is feasible within the public healthcare system of Costa Rica.

Evaluation of the GADD45α-GFP GreenScreen HC assay for rapid and reliable in vitro early genotoxicity screening.

PubMed

Luzy, Anne-Pascale; Orsini, Nicolas; Linget, Jean-Michel; Bouvier, Guy

2013-11-01

Twenty-two of Galderma's proprietary compounds were tested in the GADD45α-GFP 'GreenScreen HC' assay (GS), the SOS-ChromoTest and the Mini-Ames to evaluate GSs performance for early genotoxicity screening purposes. Forty more characterized compounds were also tested, including antibiotics: metronidazole, clindamycin, tetracycline, lymecycline and neomycin; and catecholamines: resorcinol mequinol, hydroquinone, one aneugen carbendazim, one corticoid dexamethasone, one peroxisome proliferator-activated receptor rosiglitazone, one pesticide carbaryl and two further proprietary molecules with in vitro genotoxicity data. With proprietary molecules, this study concluded that the GS renders the SOS-ChromoTest obsolete for in vitro screening. The GS confirmed all results of the Mini-Ames test (100% concordance). Compared with the micronucleus test, the GS showed a concordance of 82%. With known compounds, the GS ranked the potency of positive results for catecholamines in accordance with other genotoxicity tests and showed very reproducible results. It confirmed positive results for carbendazim, for tetracycline antibiotics and for carbaryl. The GS produced negative results for metronidazole, a nitroreduction-specific bacterial mutagen, for dexamethasone (a non-genotoxic apoptosis inducer), for rosiglitazone (a GADD45γ promoter inducer) and for clindamycin and neomycin (inhibitors of macromolecular synthesis in bacteria). As such, the GS appears to be a reproducible, robust, specific and sensitive test for genotoxicity screening. Copyright © 2012 John Wiley & Sons, Ltd.

Evaluation of an Automated Reader and Color Interpretation-Based Immunoassays for Multiplexed Drug-of-Abuse Testing in Urine.

PubMed

Kim, Seon Young; Kim, Hyunjin; Park, Yeongchun; Lim, Jinsook; Kim, Jimyung; Koo, Sun Hoe; Kwon, Gye Cheol

2017-06-01

On-site drugs of abuse testing devices have undergone continuous improvement. We evaluated three devices with different designs: an automated reader, the Multi-Drug Screen Test Device with DxLINK (DxLINK; Innovacon, Alere, San Diego, USA) and two colorimetric immunoassays, the One Step Multi-Line Screen Panel with Integrated E-Z Split Key Cup II (E-Z Cup; Innovacon, Alere) and the One Step Multi-Drug Screen Panel card (Multi4 card; Alere, Abon Biopharm, Hangzhou, China). Eleven drugs [amphetamine, secobarbital, oxazepam, buprenorphine, benzoylecgonine, methylenedioxymethamphetamine (MDMA), 11-nor-9-carboxy-Δ9-tetrahydrocannabinol (THC), methamphetamine, methadone, morphine and nortriptyline] were tested using the DxLINK and E-Z Cup. Four drugs (benzoylecgonine, THC, methamphetamine and morphine) were tested using the Multi4 card using control materials (Detectabuse Stat-Skreen; Biochemical Diagnostics, Edgewood, NY, USA). The concentrations (-50%, -25%, +25%, +50% and 3× cut-off values) of the control materials were confirmed by mass spectrometry. Concordance rates were calculated around cut-offs. All devices showed high overall agreement rates of >90% with a few exceptions: the DxLINK exhibited lower sensitivity for benzoylecgonine, methadone and nortriptyline (60% and 30%, 92% and 40%, and 96% and 60% sensitivity at +50% and +25% cut-off levels, respectively). The E-Z Cup exhibited lower sensitivity for oxazepam and nortriptyline (97% and 50%, and 97% and 40% sensitivity at +50% and +25% cut-off levels, respectively). We additionally evaluated test-band color by visual inspection using a standard color-scale card. When detailed color criteria for determination of positivity were applied for the E-Z Cup, using slightly less stringent criteria, oxazepam, buprenorphine, MDMA and nortriptyline showed increases in sensitivity from 70-80% to 90-100%, all with a specificity above 98%. Overall, all devices exhibited satisfactory performance at ±50% cut-off levels for commonly used drugs, with the exception of lower sensitivity for cocaine testing for DxLINK. Careful evaluation of devices and elaborate calibration of visual interpretation for determining positivity may help improve the performance of these devices. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Multi-centre field evaluation of the performance of the Trinity Biotech Uni-Gold HIV 1/2 rapid test as a first-line screening assay for gay and bisexual men compared with 4th generation laboratory immunoassays.

PubMed

Keen, P; Conway, D P; Cunningham, P; McNulty, A; Couldwell, D L; Davies, S C; Smith, D E; Gray, J; Holt, M; O'Connor, C C; Read, P; Callander, D; Prestage, G; Guy, R

2017-01-01

The Trinity Biotech Uni-Gold HIV test (Uni-Gold) is often used as a supplementary rapid test in testing algorithms. To evaluate the operational performance of the Uni-Gold as a first-line screening test among gay and bisexual men (GBM) in a setting where 4th generation HIV laboratory assays are routinely used. We compared the performance of Uni-Gold with conventional HIV serology conducted in parallel among GBM attending 22 testing sites. Sensitivity was calculated separately for acute and established infection, defined using 4th generation screening Ag/Ab immunoassay (EIA) and Western blot results. Previous HIV testing history and results of supplementary 3rd generation HIV Ab EIA, and p24 antigen EIA were used to further characterise cases of acute infection. Of 10,793 specimens tested with Uni-Gold and conventional serology, 94 (0.90%, 95%CI:0.70-1.07) were confirmed as HIV-positive by conventional serology, and 37 (39.4%) were classified as acute infection. Uni-Gold sensitivity was 81.9% overall (77/94, 95%CI:72.6-89.1); 56.8% for acute infection (21/37, 95%CI:39.5-72.9) and 98.2% for established infection (56/57, 95%CI:90.6-100.0). Of 17 false non-reactive Uni-Gold results, 16 were acute infections, and of these seven were p24 antigen reactive but antibody negative. Uni-Gold specificity was 99.9% (10,692/10,699, 95%CI:99.9-100.0), PPV was 91.7% (95%CI:83.6-96.6) and NPV was 99.8% (95%CI:99.7-99.9), respectively. In this population, Uni-Gold had good specificity and sensitivity was high for established infections when compared to 4th generation laboratory assays, however sensitivity was lower in acute infections. Where rapid tests are used in populations with a high proportion of acute infections, additional testing strategies are needed to detect acute infections. Copyright © 2016 Elsevier B.V. All rights reserved.

Efficacy of functional movement screening for predicting injuries in coast guard cadets.

PubMed

Knapik, Joseph J; Cosio-Lima, Ludimila M; Reynolds, Katy L; Shumway, Richard S

2015-05-01

Functional movement screening (FMS) examines the ability of individuals to perform highly specific movements with the aim of identifying individuals who have functional limitations or asymmetries. It is assumed that individuals who can more effectively accomplish the required movements have a lower injury risk. This study determined the ability of FMS to predict injuries in the United States Coast Guard (USCG) cadets. Seven hundred seventy male and 275 female USCG freshman cadets were administered the 7 FMS tests before the physically intense 8-week Summer Warfare Annual Basic (SWAB) training. Physical training-related injuries were recorded during SWAB training. Cumulative injury incidence was calculated at various FMS cutpoint scores. The ability of the FMS total score to predict injuries was examined by calculating sensitivity and specificity. Determination of the FMS cutpoint that maximized specificity and sensitivity was determined from the Youden's index (sensitivity + specificity - 1). For men, FMS scores ≤ 12 were associated with higher injury risk than scores >12; for women, FMS scores ≤ 15 were associated with higher injury risk than scores >15. The Youden's Index indicated that the optimal FMS cutpoint was ≤ 11 for men (22% sensitivity, 87% specificity) and ≤ 14 for women (60% sensitivity, 61% specificity). Functional movement screening demonstrated moderate prognostic accuracy for determining injury risk among female Coast Guard cadets but relatively low accuracy among male cadets. Attempting to predict injury risk based on the FMS test seems to have some limited promise based on the present and past investigations.

Accuracy of human papillomavirus testing on self-collected versus clinician-collected samples: a meta-analysis.

PubMed

Arbyn, Marc; Verdoodt, Freija; Snijders, Peter J F; Verhoef, Viola M J; Suonio, Eero; Dillner, Lena; Minozzi, Silvia; Bellisario, Cristina; Banzi, Rita; Zhao, Fang-Hui; Hillemanns, Peter; Anttila, Ahti

2014-02-01

Screening for human papillomavirus (HPV) infection is more effective in reducing the incidence of cervical cancer than screening using Pap smears. Moreover, HPV testing can be done on a vaginal sample self-taken by a woman, which offers an opportunity to improve screening coverage. However, the clinical accuracy of HPV testing on self-samples is not well-known. We assessed whether HPV testing on self-collected samples is equivalent to HPV testing on samples collected by clinicians. We identified relevant studies through a search of PubMed, Embase, and CENTRAL. Studies were eligible for inclusion if they fulfilled all of the following selection criteria: a cervical cell sample was self-collected by a woman followed by a sample taken by a clinician; a high-risk HPV test was done on the self-sample (index test) and HPV-testing or cytological interpretation was done on the specimen collected by the clinician (comparator tests); and the presence or absence of cervical intraepithelial neoplasia grade 2 (CIN2) or worse was verified by colposcopy and biopsy in all enrolled women or in women with one or more positive tests. The absolute accuracy for finding CIN2 or worse, or CIN grade 3 (CIN3) or worse of the index and comparator tests as well as the relative accuracy of the index versus the comparator tests were pooled using bivariate normal models and random effect models. We included data from 36 studies, which altogether enrolled 154 556 women. The absolute accuracy varied by clinical setting. In the context of screening, HPV testing on self-samples detected, on average, 76% (95% CI 69-82) of CIN2 or worse and 84% (72-92) of CIN3 or worse. The pooled absolute specificity to exclude CIN2 or worse was 86% (83-89) and 87% (84-90) to exclude CIN3 or worse. The variation of the relative accuracy of HPV testing on self-samples compared with tests on clinician-taken samples was low across settings, enabling pooling of the relative accuracy over all studies. The pooled sensitivity of HPV testing on self-samples was lower than HPV testing on a clinician-taken sample (ratio 0·88 [95% CI 0·85-0·91] for CIN2 or worse and 0·89 [0·83-0·96] for CIN3 or worse). Also specificity was lower in self-samples versus clinician-taken samples (ratio 0·96 [0·95-0·97] for CIN2 or worse and 0·96 [0·93-0·99] for CIN3 or worse). HPV testing with signal-based assays on self-samples was less sensitive and specific than testing on clinician-based samples. By contrast, some PCR-based HPV tests generally showed similar sensitivity on both self-samples and clinician-based samples. In screening programmes using signal-based assays, sampling by a clinician should be recommended. However, HPV testing on a self-sample can be suggested as an additional strategy to reach women not participating in the regular screening programme. Some PCR-based HPV tests could be considered for routine screening after careful piloting assessing feasibility, logistics, population compliance, and costs. The 7th Framework Programme of the European Commission, the Belgian Foundation against Cancer, the International Agency for Research on Cancer, and the German Guideline Program in Oncology. Copyright © 2014 Elsevier Ltd. All rights reserved.

Reverse Fluorescence Enhancement and Colorimetric Bimodal Signal Readout Immunochromatography Test Strip for Ultrasensitive Large-Scale Screening and Postoperative Monitoring.

PubMed

Yao, Yingyi; Guo, Weisheng; Zhang, Jian; Wu, Yudong; Fu, Weihua; Liu, Tingting; Wu, Xiaoli; Wang, Hanjie; Gong, Xiaoqun; Liang, Xing-Jie; Chang, Jin

2016-09-07

Ultrasensitive and quantitative fast screening of cancer biomarkers by immunochromatography test strip (ICTS) is still challenging in clinic. The gold nanoparticles (NPs) based ICTS with colorimetric readout enables a quick spectrum screening but suffers from nonquantitative performance; although ICTS with fluorescence readout (FICTS) allows quantitative detection, its sensitivity still deserves more efforts and attentions. In this work, by taking advantages of colorimetric ICTS and FICTS, we described a reverse fluorescence enhancement ICTS (rFICTS) with bimodal signal readout for ultrasensitive and quantitative fast screening of carcinoembryonic antigen (CEA). In the presence of target, gold NPs aggregation in T line induced colorimetric readout, allowing on-the-spot spectrum screening in 10 min by naked eye. Meanwhile, the reverse fluorescence enhancement signal enabled more accurately quantitative detection with better sensitivity (5.89 pg/mL for CEA), which is more than 2 orders of magnitude lower than that of the conventional FICTS. The accuracy and stability of the rFICTS were investigated with more than 100 clinical serum samples for large-scale screening. Furthermore, this rFICTS also realized postoperative monitoring by detecting CEA in a patient with colon cancer and comparing with CT imaging diagnosis. These results indicated this rFICTS is particularly suitable for point-of-care (POC) diagnostics in both resource-rich and resource-limited settings.

Cost-effectiveness of orthoptic screening in kindergarten: a decision-analytic model.

PubMed

König, H H; Barry, J C; Leidl, R; Zrenner, E

2000-06-01

The purpose of this study was to analyze the cost-effectiveness of orthoptic screening for amblyopia in kindergarten. A decision-analytic model was used. In this model all kindergarten children in Germany aged 3 years were examined by an orthoptist. Children with positive screening results were referred to an ophthalmologist for diagnosis. The number of newly diagnosed cases of amblyopia, amblyogenic non-obvious strabismus and amblyogenic refractive errors was used as the measure of effectiveness. Direct costs were measured form a third-party payer perspective. Data for model parameters were obtained from the literature and from own measurements in kindergartens. A base analysis was performed using median parameter values. The influence of uncertain parameters was tested in sensitivity analyses. According to the base analysis, the cost of one orthoptic screening test was 7.87 euro. One ophthalmologic examination cost 36.40 euro. The total cost of the screening program in all kindergartens was 3.1 million euro. A total of 4,261 new cases would be detected. The cost-effectiveness ratio was 727 euro per case detected. Sensitivity analysis showed considerable influence of the prevalence rate of target conditions and of the specificity of the orthopic examination on the cost-effectiveness ratio. This analysis provides information which is useful for discussion about the implementation of orthoptic screening and for planning a field study.

SpermCheck: a simplified screening assay for immunological infertility.

PubMed

McClure, R D; Tom, R A; Watkins, M; Murthy, S

1989-10-01

SpermCheck (Bio-Rad Laboratories, Hercules, CA), a new screening test for regional surface antibodies on motile sperm, uses monodispersed latex microspheres of uniform size as a vehicle to link rabbit antihuman immunoglobulins (IgA, IgG, IgM) and provides both negative and positive control sera, as well as sufficient buffer for sperm preparation in ambient CO2 atmosphere. When compared with reference data available for the immunobead test (IBT), the direct protocol (semen) for SpermCheck yielded 94.4% sensitivity with 100% specificity; the indirect protocol (serum) provided a sensitivity of 100% with 94.7% specificity. The microspheres of SpermCheck maintain a nearly uniform concentration per volume, with none to negligible clumping. The greater difference between the optical densities of latex and cytoplasm allows use of a light microscope for the rapid assessment of the percent of regional binding rather than the phase-contrast microscope required for the IBT. SpermCheck eliminates many difficulties encountered with the IBT, making SpermCheck a convenient screening assay for use in the physician's office.

Screening for Binge Eating Disorders Using the Patient Health Questionnaire in a Community Sample

PubMed Central

Striegel-Moore, Ruth H.; Perrin, Nancy; DeBar, Lynn; Wilson, G. Terence; Rosselli, Francine; Kraemer, Helena C.

2009-01-01

Objective To examine the operating characteristics of the Patient Health Questionnaire eating disorder module (PHQ-ED) for identifying bulimia nervosa/binge eating disorder (BN/BED) or recurrent binge eating (RBE) in a community sample, and to compare true positive (TP) versus false positive (FP) cases on clinical validators. Method 259 screen positive individuals and a random sample of 89 screen negative cases completed a diagnostic interview. Sensitivity, specificity, and Positive Predictive Value (PPV) were calculated. TP and FP cases were compared using t-tests and Chi-Square tests. Results The PHQ-ED had high sensitivity (100%) and specificity (92%) for detecting BN/BED or RBE, but PPV was low (15% or 19%). TP and FP cases did not differ significantly on frequency of subjective bulimic episodes, objective overeating, restraint, on BMI, and on self-rated health. Conclusions The PHQ-ED is recommended for use in large populations only in conjunction with follow-up questions to rule out cases without objective bulimic episodes. PMID:19424976

Receipt of Glucose Testing and Performance of Two US Diabetes Screening Guidelines, 2007–2012

PubMed Central

Bullard, Kai McKeever; Ali, Mohammed K.; Imperatore, Giuseppina; Geiss, Linda S.; Saydah, Sharon H.; Albu, Jeanine B.; Cowie, Catherine C.; Sohler, Nancy; Albright, Ann; Gregg, Edward W.

2015-01-01

Background Screening guidelines are used to help identify prediabetes and diabetes before implementing evidence-based prevention and treatment interventions. We examined screening practices benchmarking against two US guidelines, and the capacity of each guideline to identify dysglycemia. Methods Using 2007–2012 National Health and Nutrition Examination Surveys, we analyzed nationally-representative, cross-sectional data from 5,813 fasting non-pregnant adults aged ≥20 years without self-reported diabetes. We examined proportions of adults eligible for diagnostic glucose testing and those who self-reported receiving testing in the past three years, as recommended by the American Diabetes Association (ADA) and the US Preventive Services Task Force (USPSTF-2008) guidelines. For each screening guideline, we also assessed sensitivity, specificity, and positive (PPV) and negative predictive values in identifying dysglycemia (defined as fasting plasma glucose ≥100 mg/dl or hemoglobin A1c ≥5.7%). Results In 2007–2012, 73.0% and 23.7% of US adults without diagnosed diabetes met ADA and USPSTF-2008 criteria for screening, respectively; and 91.5% had at least one major risk factor for diabetes. Of those ADA- or USPSTF-eligible adults, about 51% reported being tested within the past three years. Eligible individuals not tested were more likely to be lower educated, poorer, uninsured, or have no usual place of care compared to tested eligible adults. Among adults with ≥1 major risk factor, 45.7% reported being tested, and dysglycemia yields (i.e., PPV) ranged from 45.8% (high-risk ethnicity) to 72.6% (self-reported prediabetes). ADA criteria and having any risk factor were more sensitive than the USPSTF-2008 guideline (88.8–97.7% vs. 31.0%) but less specific (13.5–39.7% vs. 82.1%) in recommending glucose testing, resulting in lower PPVs (47.7–54.4% vs. 58.4%). Conclusion Diverging recommendations and variable performance of different guidelines may be impeding national diabetes prevention and treatment efforts. Efforts to align screening recommendations may result in earlier identification of adults at high risk for prediabetes and diabetes. PMID:25928306

Comparison of cytology, HPV DNA testing and HPV 16/18 genotyping alone or combined targeting to the more balanced methodology for cervical cancer screening.

PubMed

Chatzistamatiou, Kimon; Moysiadis, Theodoros; Moschaki, Viktoria; Panteleris, Nikolaos; Agorastos, Theodoros

2016-07-01

The objective of the present study was to identify the most effective cervical cancer screening algorithm incorporating different combinations of cytology, HPV testing and genotyping. Women 25-55years old recruited for the "HERMES" (HEllenic Real life Multicentric cErvical Screening) study were screened in terms of cytology and high-risk (hr) HPV testing with HPV 16/18 genotyping. Women positive for cytology or/and hrHPV were referred for colposcopy, biopsy and treatment. Ten screening algorithms based on different combinations of cytology, HPV testing and HPV 16/18 genotyping were investigated in terms of diagnostic accuracy. Three clusters of algorithms were formed according to the balance between effectiveness and harm caused by screening. The cluster showing the best balance included two algorithms based on co-testing and two based on HPV primary screening with HPV 16/18 genotyping. Among these, hrHPV testing with HPV 16/18 genotyping and reflex cytology (atypical squamous cells of undetermined significance - ASCUS threshold) presented the optimal combination of sensitivity (82.9%) and specificity relative to cytology alone (0.99) with 1.26 false positive rate relative to cytology alone. HPV testing with HPV 16/18 genotyping, referring HPV 16/18 positive women directly to colposcopy, and hrHPV (non 16/18) positive women to reflex cytology (ASCUS threshold), as a triage method to colposcopy, reflects the best equilibrium between screening effectiveness and harm. Algorithms, based on cytology as initial screening method, on co-testing or HPV primary without genotyping, and on HPV primary with genotyping but without cytology triage, are not supported according to the present analysis. Copyright © 2016 Elsevier Inc. All rights reserved.

The influence of film-screen color sensitivity and type of measurement device on kVp measurements.

PubMed

Lam, R W; Price, S C

1989-01-01

Three methods for evaluating radiographic kVp were studied: the Wisconsin Test Cassette, the Noninvasive Evaluator of Radiation Outputs (NERO), and the Dynalyzer. The Dynalyzer kVp readings were the highest and were followed by NERO and cassette readings in descending order. By film type, the cassette readings ranged from Kodak OG (green sensitive), TMG (green sensitive), XK (blue sensitive), and XRP (blue sensitive) in descending order. The results show that there is significant variation between the methods.

Cost-effectiveness of cervical cancer screening with primary human papillomavirus testing in Norway

PubMed Central

Burger, E A; Ortendahl, J D; Sy, S; Kristiansen, I S; Kim, J J

2012-01-01

Background: New screening technologies and vaccination against human papillomavirus (HPV), the necessary cause of cervical cancer, may impact optimal approaches to prevent cervical cancer. We evaluated the cost-effectiveness of alternative screening strategies to inform cervical cancer prevention guidelines in Norway. Methods: We leveraged the primary epidemiologic and economic data from Norway to contextualise a simulation model of HPV-induced cervical cancer. The current cytology-only screening was compared with strategies involving cytology at younger ages and primary HPV-based screening at older ages (31/34+ years), an option being actively deliberated by the Norwegian government. We varied the switch-age, screening interval, and triage strategies for women with HPV-positive results. Uncertainty was evaluated in sensitivity analysis. Results: Current cytology-only screening was less effective and more costly than strategies that involve switching to primary HPV testing in older ages. For unvaccinated women, switching at age 34 years to primary HPV testing every 4 years was optimal given the Norwegian cost-effectiveness threshold ($83 000 per year of life saved). For vaccinated women, a 6-year screening interval was cost-effective. When we considered a wider range of strategies, we found that an earlier switch to HPV testing (at age 31 years) may be preferred. Conclusions: Strategies involving a switch to HPV testing for primary screening in older women is expected to be cost-effective compared with current recommendations in Norway. PMID:22441643

New technologies in cervical cancer precursor detection.

PubMed

Soler, M E; Blumenthal, P D

2000-09-01

The current literature reflects three routes toward improving cervical cancer screening. The first is to improve the test qualities of cytology-based screening. The use of liquid-based cytology and computerized analysis of Papanicolaou tests are examples of attempts at this approach. Secondly, through various combinations of parallel or sequential tests, either the sensitivity or the specificity of a given test could be improved depending on the tests chosen and the order in which they were performed (eg, Papanicolaou test followed by human papillomavirus [HPV] or vice versa). Several excellent studies have been published this year on the use of HPV DNA testing as a primary screening modality and as an adjunct to the triage of mildly abnormal cytologic findings. The recent literature also reflects increasing interest in visual inspection of the cervix and self-collected samples for HPV testing as an equally effective and viable alternative to cytology in low-resource settings. A third possibility is to make use of advances in digital and spectroscopic techniques. In these cost-conscious times, a significant number of articles address the cost-effectiveness of these technologies and the real value of cervical cancer screening. This article reviews the current literature concerning both the advent of new cervical cancer screening technologies and the rediscovery of old ones.

Diagnostic accuracy of a two-item Drug Abuse Screening Test (DAST-2).

PubMed

Tiet, Quyen Q; Leyva, Yani E; Moos, Rudolf H; Smith, Brandy

2017-11-01

Drug use is prevalent and costly to society, but individuals with drug use disorders (DUDs) are under-diagnosed and under-treated, particularly in primary care (PC) settings. Drug screening instruments have been developed to identify patients with DUDs and facilitate treatment. The Drug Abuse Screening Test (DAST) is one of the most well-known drug screening instruments. However, similar to many such instruments, it is too long for routine use in busy PC settings. This study developed and validated a briefer and more practical DAST for busy PC settings. We recruited 1300 PC patients in two Department of Veterans Affairs (VA) clinics. Participants responded to a structured diagnostic interview. We randomly selected half of the sample to develop and the other half to validate the new instrument. We employed signal detection techniques to select the best DAST items to identify DUDs (based on the MINI) and negative consequences of drug use (measured by the Inventory of Drug Use Consequences). Performance indicators were calculated. The two-item DAST (DAST-2) was 97% sensitive and 91% specific for DUDs in the development sample and 95% sensitive and 89% specific in the validation sample. It was highly sensitive and specific for DUD and negative consequences of drug use in subgroups of patients, including gender, age, race/ethnicity, marital status, educational level, and posttraumatic stress disorder status. The DAST-2 is an appropriate drug screening instrument for routine use in PC settings in the VA and may be applicable in broader range of PC clinics. Published by Elsevier Ltd.

Screening for gonorrhoea using samples collected through the English National Chlamydia Screening Programme and risk of false positives: a national survey of Local Authorities

PubMed Central

Field, Nigel; Kennedy, Iain; Folkard, Kate; Duffell, Stephen; Town, Katy; Ison, Catherine A; Hughes, Gwenda

2014-01-01

Objectives To investigate use of dual tests for Chlamydia trachomatis and Neisseria gonorrhoeae on samples collected through the National Chlamydia Screening Programme (NCSP) in England. Design and setting During May–July 2013, we delivered an online survey to commissioners of sexual health services in the 152 upper-tier English Local Authorities (LAs) who were responsible for commissioning chlamydia screening in people aged 15–24 years. Main outcome measures (1) The proportion of English LAs using dual tests on samples collected by the NCSP; (2) The estimated number of gonorrhoea tests and false positives from samples collected by the NCSP, calculated using national surveillance data on the number of chlamydia tests performed, assuming the gonorrhoea prevalence to range between 0.1% and 1%, and test sensitivity and specificity of 99.5%. Results 64% (98/152) of LAs responded to this national survey; over half (53% (52/98)) reported currently using dual tests in community settings. There was no significant difference between LAs using and not using dual tests by chlamydia positivity, chlamydia diagnosis rate or population screening coverage. Although positive gonorrhoea results were confirmed with supplementary tests in 93% (38/41) of LAs, this occurred after patients were notified about the initial positive result in 63% (26/41). Approximately 450–4500 confirmed gonorrhoea diagnoses and 2300 false-positive screens might occur through use of dual tests on NCSP samples each year. Under reasonable assumptions, the positive predictive value of the screening test is 17–67%. Conclusions Over half of English LAs already commission dual tests for samples collected by the NCSP. Gonorrhoea screening has been introduced alongside chlamydia screening in many low prevalence settings without a national evidence review or change of policy. We question the public health benefit here, and suggest that robust testing algorithms and clinical management pathways, together with rigorous evaluation, be implemented wherever dual tests are deployed. PMID:25324326

Screening for Syphilis: Updated Evidence Report and Systematic Review for the US Preventive Services Task Force.

PubMed

Cantor, Amy G; Pappas, Miranda; Daeges, Monica; Nelson, Heidi D

2016-06-07

Screening for syphilis infection is currently recommended for high-risk individuals, including those with previous syphilis infection, an infected sexual partner, HIV infection, or more than 4 sex partners in the preceding year. To update a 2004 systematic review of studies of syphilis screening effectiveness, test accuracy, and screening harms in nonpregnant adults and adolescents. Cochrane Central Register of Controlled Trials and Cochrane Database of Systematic Reviews through October 2015 and Ovid MEDLINE (January 2004 to October 2015), with updated search through March 2016. English-language trials and observational studies of screening effectiveness, test accuracy, and screening harms in nonpregnant adults and adolescents. One investigator abstracted data, a second checked data for accuracy, and 2 investigators independently assessed study quality using predefined criteria. Transmission of disease, including HIV; complications of syphilis; diagnostic accuracy; and harms of screening. No evidence was identified regarding the effectiveness of screening on clinical outcomes or the effectiveness of risk assessment instruments; the harms of screening; or the effectiveness of screening in average-risk, nonpregnant adolescents or adults or high-risk individuals other than men who have sex with men (MSM) or men who are HIV positive. Four non-US studies indicated higher rates of syphilis detection with screening every 3 months vs 6 or 12 months for early syphilis in HIV-positive men or MSM. For example, there was an increased proportion of asymptomatic, higher-risk MSM in Australia (n = 6789 consultations) receiving a diagnosis of early syphilis when tested every 3 months vs annually (53% vs 16%, P = .001), but no difference among low-risk MSM. Treponemal and nontreponemal tests were accurate in asymptomatic individuals (sensitivity >85%, specificity >91%) in 3 studies but required confirmatory testing. Reverse sequence testing with an initial automated treponemal test yielded more false reactive test results than with rapid plasma reagin in 2 studies, one with a low-prevalence US population (0.6% vs 0.0%, P = .03) and another in a higher-prevalence Canadian population (0.26% vs 0.13%). Screening HIV-positive men or MSM for syphilis every 3 months is associated with improved syphilis detection. Treponemal or nontreponemal tests are accurate screening tests but require confirmation. Research is needed on the effect of screening on clinical outcomes; effective screening strategies, including reverse sequence screening, in various patient populations; and harms of screening.

Screening with HbA1c identifies only one in two individuals with diagnosis of prediabetes at oral glucose tolerance test: findings in a real-world Caucasian population.

PubMed

Chilelli, Nino Cristiano; Cosma, Chiara; Ragazzi, Eugenio; Burlina, Silvia; Zaninotto, Martina; Plebani, Mario; Lapolla, Annunziata

2014-10-01

Discordance between HbA1c and OGTT in screening pre-diabetes may occur because of lack of laboratory standardization, distinct underlying pathophysiological processes or different ethnicity. We evaluated HbA1c efficacy for screening OGTT-defined IFG and IGT conditions in a large Caucasian population using the newly revised IFCC protocol. A total of 501 consecutive subjects were screened for pre-diabetic conditions with OGTT with 75 g of glucose. Testing for HbA1c, lipid profile and fasting insulin levels was also performed. For detecting differences between continuous variables, ANOVA followed by Tukey's honestly significant difference (HSD) post hoc test was used. Logistic regression and ROC curve analysis were also performed for assessing HbA1c screening efficacy. ROC curve analysis showed that optimal HbA1c cut-off for detecting IFG was 5.6 % (sensitivity of 78 % and specificity of 63 %), while for IGT, the optimal cut-off was 5.9 % (sensitivity of 46 % and specificity of 84 %), with AUCs < 0.8. Screening with HbA1c identified 53.4 % of the 193 patients with IFG and/or IGT diagnosed at OGTT. As regards surrogate markers of insulin resistance, we observed a trend towards higher values of HOMA-IR and lower QUICKI values in subjects with IFG than in those with IGT. Patients with pre-diabetes at both tests had similar values of HOMA and QUICKI, compared with those with altered OGTT only. IFCC-aligned HbA1c assay proved scarcely effective in detecting IFG and/or IGT in a large Caucasian population, identifying only half of the patients with abnormal OGTT. Moreover, adding HbA1c screening to OGTT may be of little benefit in identifying subjects with a worse metabolic profile.

Feasibility and diagnostic accuracy of early mood screening to diagnose persisting clinical depression/anxiety disorder after stroke.

PubMed

Lees, Rosalind; Stott, David J; Quinn, Terence J; Broomfield, Niall M

2014-01-01

Depression/anxiety disorders are common after stroke and have a negative impact on outcomes. Guidelines recommend that all stroke survivors are screened for these problems. However, there is no consensus on timing or method of assessment. We investigated the feasibility and accuracy of a very early screening strategy and the diagnostic accuracy this has for depression/anxiety disorders at 1 month. Screening tools were Hospital Anxiety and Depression Scale (HADS) and Depression Intensity Scale Circles (DISCs); we also assessed cognition using the Montreal Cognitive Assessment (MoCA). Screening was offered to sequential stroke admissions. At 1 month we assessed for clinical depression/anxiety disorder using Mini-International Neuropsychiatric Interview (MINI) and retested screening tools. We described test accuracy of acute depression/anxiety screening for clinical diagnosis of depression/anxiety disorder at 1 month and described temporal change in screening test scores. We assessed feasibility by describing proportions that were able, agreed to and completed the screening tests. Over 4 months, 102/146 admissions were suitable for screening following initial medical assessment, 69 (68%) agreed to screening, of whom 33 (48%) required researcher assistance to complete the screening test battery. Median time to assessment was 2 days (IQR: 1-4). Early HADS suggested n = 9 (13%) with depression; DISCs n = 25 (37%). Median acute MoCA was 21/30. At 1 month, n = 61 (88%) provided data. Repeat scores showed improvement over time; HADS (anxiety) mean difference: 2.5 (95% CI: 1.2-3.7), HADS (depression) mean difference: 1.6 (95% CI: 0.3-2.9). MINI defined n = 12 (20%) with depression and n = 6 (10%) with anxiety disorder. Comparing baseline screening to 1-month clinical diagnosis, HADS sensitivity was 0.25 (95% CI: 0.09-0.53) and specificity 0.94 (95% CI: 0.84-0.98); DISCs sensitivity was 0.92 (95% CI: 0.65-0.99) and specificity 0.78 (95% CI: 0.64-0.87). Even amongst 'medically stable' stroke patients, depression/anxiety screening at the acute stage may not be feasible or accurate. Half of participants required assistance from the researcher to complete assessments. The poor predictive accuracy of HADS for depression/anxiety disorder at 1 month may be due in part to the high prevalence of cognitive impairment in our sample. Screening in the first few days after stroke does not appear useful for detecting clinically important and sustained depression/anxiety problems. © 2014 S. Karger AG, Basel.

A Dual Point-of-Care Test Shows Good Performance in Simultaneously Detecting Nontreponemal and Treponemal Antibodies in Patients With Syphilis: A Multisite Evaluation Study in China

PubMed Central

Yin, Yue-Ping; Chen, Xiang-Sheng; Wei, Wan-Hui; Gong, Kuang-Long; Cao, Wen-Ling; Yong, Gang; Feng, Liang; Huang, Shu-Jie; Wang, Dong-Mei; Han, Yan; Chen, Shao-Chun; Mabey, David; Peeling, Rosanna W.

2013-01-01

Background. Rapid point-of-care (POC) syphilis tests based on simultaneous detection of treponemal and nontreponemal antibodies (dual POC tests) offer the opportunity to increase coverage of syphilis screening and treatment. This study aimed to conduct a multisite performance evaluation of a dual POC syphilis test in China. Methods. Participants were recruited from patients at sexually transmitted infection clinics and high-risk groups in outreach settings in 6 sites in China. Three kinds of specimens (whole blood [WB], fingerprick blood [FB], and blood plasma [BP]) were used for evaluating sensitivity and specificity of the Dual Path Platform (DPP) Syphilis Screen and Confirm test using its treponemal and nontreponemal lines to compare Treponema pallidum particle agglutination (TPPA) assay and toluidine red unheated serum test (TRUST) as reference standards. Results. A total of 3134 specimens (WB 1323, FB 488, and BP 1323) from 1323 individuals were collected. The sensitivities as compared with TPPA were 96.7% for WB, 96.4% for FB, and 94.6% for BP, and the specificities were 99.3%, 99.1%, and 99.6%, respectively. The sensitivities as compared with TRUST were 87.2% for WB, 85.8% for FB, and 88.4% for BP, and the specificities were 94.4%, 96.1%, and 95.0%, respectively. For specimens with a TRUST titer of 1:4 or higher, the sensitivities were 100.0% for WB, 97.8% for FB, and 99.6% for BP. Conclusions. DPP test shows good sensitivity and specificity in detecting treponemal and nontreponemal antibodies in 3 kinds of specimens. It is hoped that this assay can be considered as an alternative in the diagnosis of syphilis, particularly in resource-limited areas. PMID:23132172

Immunochemical faecal occult blood test for colorectal cancer screening: a systematic review.

PubMed

Syful Azlie, M F; Hassan, M R; Junainah, S; Rugayah, B

2015-02-01

A systematic review on the effectiveness and costeffectiveness of Immunochemical faecal occult IFOBT for CRC screening was carried out. A total of 450 relevant titles were identified, 41 abstracts were screened and 18 articles were included in the results. There was fair level of retrievable evidence to suggest that the sensitivity and specificity of IFOBT varies with the cut-off point of haemoglobin, whereas the diagnostic accuracy performance was influenced by high temperature and haemoglobin stability. A screening programme using IFOBT can be effective for prevention of advanced CRC and reduced mortality. There was also evidence to suggest that IFOBT is cost-effective in comparison with no screening, whereby a two-day faecal collection method was found to be costeffective as a means of screening for CRC. Based on the review, quantitative IFOBT method can be used in Malaysia as a screening test for CRC. The use of fully automated IFOBT assay would be highly desirable.

[New intensifying screens in clinical radiology. II. Examinations in clinical practice].

PubMed

Freyschmidt, J; Saure, D; Hagemann, G

1976-09-01

A clinically applicable procedure for testing new intensifying rare earth screens, as well as the special Siemens' screen is described. The results are related to universal screens. The film-screen combination alpha 4XD (gadolinium oxysulphide with normal, green sensitive film) results in a reduction of radiation dose to half with detail comparable with universal screens. The Siemens' special screen has similar advantages. Screens with a higher intensification factor and reduction of the mAs to one sixth results in loss of detail. This does not necessarily reduce their clinical use if they are used for appropriate purposes. The results of this clinically orientated technique agreed well with physically objective methods using lead grids. The advantages of the new screens are discussed in terms of their practical application.

Study on the resistance mechanism via outer membrane protein OprD2 and metal β-lactamase expression in the cell wall of Pseudomonas aeruginosa.

PubMed

Cai, Shuangqi; Chen, Yiqiang; Song, Dezhi; Kong, Jinliang; Wu, Yanbin; Lu, Huasong

2016-11-01

The aim of the present study was to evaluate the imipenem-resistant mechanism via the outer membrane protein (OMP) OprD2 and metal β-lactamase expression in the cell wall of Pseudomonas aeruginosa . The Pseudomonas aeruginosa was clinically separated and validated by VITEK-2 full-automatic bacteria analyzer. Drug resistance, sensitive antibiotics and minimum inhibitory concentration (MIC) were tested using the drug sensitivity analysis system. The phenotype positive strains of MBL genes were screened using the Kirby-Bauer diffusion method by adding metal ion-chelating agent EDTA on the imipenem susceptibility paper. IMP-1, VIM-1 and SPM metaloenzyme genes were tested by polymerase chain reaction (PCR)-telomeric repeat amplification protocol (TRAP). The OMP OprD2 genes were tested by PCR-TRAP, and the protein expression was tested using western blot analysis. The location of OMP OprD2 was confirmed using the sodium salicylate inhibition test. The results showed that 80 portions (40%) of MBL-positive strains were screened out of 200 specimens. Imipenem-resistant Pseudomonas aeruginosa (IRPA) and MIC values were significantly higher than quality control bacteria and control bacteria (P<0.05). A total of 35 cases with IMP-1 positive, 20 with VIM-1 positive, 16 with SPM positive, 5 with 2 positive genes and 4 with 3 positive genes were screened among MBL positive strains. A total of 150 portions (75%) of OprD2 deficiencies were screened from 200 specimens. The standard strains and sensitive strains showed OprD2 protein bands at 45 kDa while no OprD2 protein bands appeared in OprD2 deficiency strains. It was in accordance with gene detection. In conclusion, OMP OprD2 deficiency and MBL phenotype positivity may be important mechanisms of IRPA.

Cost-effectiveness of HPV-based cervical cancer screening in the public health system in Nicaragua.

PubMed

Campos, Nicole G; Mvundura, Mercy; Jeronimo, Jose; Holme, Francesca; Vodicka, Elisabeth; Kim, Jane J

2017-06-15

To evaluate the cost-effectiveness of human papillomavirus (HPV) DNA testing (versus Papanicolaou (Pap)-based screening) for cervical cancer screening in Nicaragua. A previously developed Monte Carlo simulation model of the natural history of HPV infection and cervical cancer was calibrated to epidemiological data from Nicaragua. Cost data inputs were derived using a micro-costing approach in Carazo, Chontales and Chinandega departments; test performance data were from a demonstration project in Masaya department. Nicaragua's public health sector facilities. Women aged 30-59 years. Screening strategies included (1) Pap testing every 3 years, with referral to colposcopy for women with an atypical squamous cells of undetermined significance or worse result ('Pap'); (2) HPV testing every 5 years, with referral to cryotherapy for HPV-positive eligible women (HPV cryotherapy or 'HPV-Cryo'); (3) HPV testing every 5 years, with referral to triage with visual inspection with acetic acid (VIA) for HPV-positive women ('HPV-VIA'); and (4) HPV testing every 5 years, with referral to Pap testing for HPV-positive women ('HPV-Pap'). Reduction in lifetime risk of cancer and incremental cost-effectiveness ratios (ICER; 2015 US$ per year of life saved (YLS)). HPV-based screening strategies were more effective than Pap testing. HPV-Cryo was the least costly and most effective strategy, reducing lifetime cancer risk by 29.5% and outperforming HPV-VIA, HPV-Pap and Pap only, which reduced cancer risk by 19.4%, 12.2% and 10.8%, respectively. With an ICER of US$320/YLS, HPV-Cryo every 5 years would be very cost-effective using a threshold based on Nicaragua's per capita gross domestic product of US$2090. Findings were robust across sensitivity analyses on test performance, coverage, compliance and cost parameters. HPV testing is very cost-effective compared with Pap testing in Nicaragua, due to higher test sensitivity and the relatively lower number of visits required. Increasing compliance with recommended follow-up will further improve the health benefits and value for public health dollars. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Cost-effectiveness of HPV-based cervical cancer screening in the public health system in Nicaragua

PubMed Central

Mvundura, Mercy; Jeronimo, Jose; Holme, Francesca; Vodicka, Elisabeth; Kim, Jane J

2017-01-01

Objectives To evaluate the cost-effectiveness of human papillomavirus (HPV) DNA testing (versus Papanicolaou (Pap)-based screening) for cervical cancer screening in Nicaragua. Design A previously developed Monte Carlo simulation model of the natural history of HPV infection and cervical cancer was calibrated to epidemiological data from Nicaragua. Cost data inputs were derived using a micro-costing approach in Carazo, Chontales and Chinandega departments; test performance data were from a demonstration project in Masaya department. Setting Nicaragua’s public health sector facilities. Participants Women aged 30–59 years. Interventions Screening strategies included (1) Pap testing every 3 years, with referral to colposcopy for women with an atypical squamous cells of undetermined significance or worse result (‘Pap’); (2) HPV testing every 5 years, with referral to cryotherapy for HPV-positive eligible women (HPV cryotherapy or ‘HPV-Cryo’); (3) HPV testing every 5 years, with referral to triage with visual inspection with acetic acid (VIA) for HPV-positive women (‘HPV-VIA’); and (4) HPV testing every 5 years, with referral to Pap testing for HPV-positive women (‘HPV-Pap’). Outcome measures Reduction in lifetime risk of cancer and incremental cost-effectiveness ratios (ICER; 2015 US$ per year of life saved (YLS)). Results HPV-based screening strategies were more effective than Pap testing. HPV-Cryo was the least costly and most effective strategy, reducing lifetime cancer risk by 29.5% and outperforming HPV-VIA, HPV-Pap and Pap only, which reduced cancer risk by 19.4%, 12.2% and 10.8%, respectively. With an ICER of US$320/YLS, HPV-Cryo every 5 years would be very cost-effective using a threshold based on Nicaragua’s per capita gross domestic product of US$2090. Findings were robust across sensitivity analyses on test performance, coverage, compliance and cost parameters. Conclusions HPV testing is very cost-effective compared with Pap testing in Nicaragua, due to higher test sensitivity and the relatively lower number of visits required. Increasing compliance with recommended follow-up will further improve the health benefits and value for public health dollars. PMID:28619772

The Combined Utility of a Brief Functional Measure and Performance-Based Screening Test for Case Finding of Cognitive Impairment in Primary Healthcare.

PubMed

Chan, Qun Lin; Shaik, Muhammad Amin; Xu, Jing; Xu, Xin; Chen, Christopher Li-Hsian; Dong, YanHong

2016-04-01

Use of a total risk score (TRS) based on vascular and sociodemographic risk factors has been recommended to identify patients at risk of cognitive impairment. Moreover, combining screening tests has been reported to improve positive predictive values (PPV) for case finding of cognitive impairment. We investigated the utility of the conjunctive combination of the informant-based AD8 and the performance-based National Institute of Neurological Disorders and Stroke-Canadian Stroke Network (NINDS-CSN) 5-minute protocol for the detection of cognitive impairment, defined by a clinical dementia rating (CDR) score ≥0.5, in patients at risk of cognitive impairment (TRS ≥3). Participants were recruited from 2 primary healthcare centers in Singapore and received the AD8, Montreal Cognitive Assessment, Mini-Mental State Examination, CDR, and a formal neuropsychological test battery. The scores for NINDS-CSN 5-minute protocol were extracted from the Montreal Cognitive Assessment items. Area under the receiver operating characteristics curve analyses were conducted to determine the discriminant indices of the screening instruments, the conjunctive combination (ie, screened positive on both tests), and the compensatory combination (ie, screened positive in either of or both tests). A total of 309 participants were recruited of whom 78.7% (n = 243) had CDR = 0 and 21.3% (n = 66) had CDR ≥0.5. The conjunctive combination of AD8 and NINDS-CSN 5-minute protocol achieved excellent PPV and acceptable sensitivity (PPV 91.7%, sensitivity 73.3%). The conjunctive combination of the AD8 and NINDS-CSN 5-minute protocol is brief and accurate, and hence, suitable for case finding of cognitive impairment (CDR ≥0.5) in patients screened positive on the TRS in primary healthcare centers. Copyright © 2016. Published by Elsevier Inc.

PAX1 Methylation Hallmarks Promising Accuracy for Cervical Cancer Screening in Asians: Results from a Meta-Analysis.

PubMed

Kong, Ling-Ying; Du, Wei; Wang, Li; Yang, Zhi; Zhang, Hong-Sheng

2015-01-01

DNA methylation has been proposed as a potential biomarker for cervical cancer detection. This study aimed to evaluate the diagnostic role of paired boxed gene 1 (PAX1) methylation for cervical cancer screening in Asians. Eligible studies were retrieved by searching the electronic databases, and the quality of the enrolled studies was assessed via the quality assessment for studies of diagnostic accuracy (QUADAS) tool. The bivariate meta-analysis model was employed to generate the summary receiver operator characteristic (SROC) curve using Stata 12.0 software. Cochran's Q test and I2 statistics were applied to assess heterogeneity among studies. Publication bias was evaluated by the Deeks' funnel plot asymmetry test. A total of 9 articles containing 15 individual studies were included. The SROC analysis showed that single PAX1 methylation allowed for the discrimination between cancer/high-grade squamous intraepithelial lesion (HSIL) patients and normal individuals with a sensitivity (95% confidence interval) of 0.80 (0.70 - 0.87) and specificity of 0.89 (0.86 - 0.92), corresponding to an area under curve (AUC) of 0.92. Notably, our subgroup analysis suggested that combing parallel testing of PAX1 methylation and HPV DNA (AUC, sensitivity, and specificity of 0.90, 0.82, and 0.84, respectively) seemed to harbor higher accuracy than single HPV DNA testing (AUC, sensitivity, and specificity of 0.81, 0.86, and 0.67, respectively). PAX1 methylation hallmarks a potential diagnostic value for cervical cancer screening in Asians, and parallel testing of PAX1 methylation and HPV in cervical scrapings confers an improved accuracy than single HPV DNA testing.

Clinical flow cytometric screening of SAP and XIAP expression accurately identifies patients with SH2D1A and XIAP/BIRC4 mutations.

PubMed

Gifford, Carrie E; Weingartner, Elizabeth; Villanueva, Joyce; Johnson, Judith; Zhang, Kejian; Filipovich, Alexandra H; Bleesing, Jack J; Marsh, Rebecca A

2014-07-01

X-linked lymphoproliferative disease is caused by mutations in two genes, SH2D1A and XIAP/BIRC4. Flow cytometric methods have been developed to detect the gene products, SAP and XIAP. However, there is no literature describing the accuracy of flow cytometric screening performed in a clinical lab setting. We reviewed the clinical flow cytometric testing results for 656 SAP and 586 XIAP samples tested during a 3-year period. Genetic testing was clinically performed as directed by the managing physician in 137 SAP (21%) and 115 XIAP (20%) samples. We included these samples for analyses of flow cytometric test accuracy. SH2D1A mutations were detected in 15/137 samples. SAP expression was low in 13/15 (sensitivity 87%, CI 61-97%). Of the 122 samples with normal sequencing, SAP was normal in 109 (specificity 89%, CI 82-94%). The positive predictive values (PPVs) and the negative predictive values (NPVs) were 50% and 98%, respectively. XIAP/BIRC4 mutations were detected in 19/115 samples. XIAP expression was low in 18/19 (sensitivity 95%, CI 73-100%). Of the 96 samples with normal sequencing, 59 had normal XIAP expression (specificity 61%, CI 51-71%). The PPVs and NPVs were 33% and 98%, respectively. Receiver-operating characteristic analysis was able to improve the specificity to 75%. Clinical flow cytometric screening tests for SAP and XIAP deficiencies offer good sensitivity and specificity for detecting genetic mutations, and are characterized by high NPVs. We recommend these tests for patients suspected of having X-linked lymphoproliferative disease type 1 (XLP1) or XLP2. © 2014 Clinical Cytometry Society.

Comparison of Three Biochemical Tests for Rapid Detection of Extended-Spectrum-β-Lactamase-Producing Enterobacteriaceae.

PubMed

Poirel, Laurent; Fernández, Javier; Nordmann, Patrice

2016-02-01

Enterobacterial isolates producing clavulanic-inhibited extended-spectrum β-lactamases (ESBLs) are increasingly spreading in the community and are often responsible for nosocomial infections. Rapid biochemical tests have been developed recently for their detection. Three tests, namely, the Rapid ESBL NDP test, the β-Lacta test, and the Rapid ESBL Screen, have been evaluated with a collection of 108 well-characterized strains, including wild-type strains, strains producing ESBLs, overexpressed cephalosporinases, and carbapenemases. The ESBL NDP test and the Rapid ESBL Screen (a copy of the ESBL NDP test) are aimed at detecting ESBL producers, while the β-Lacta test is aimed at detecting not only ESBL producers but also cephalosporinase and carbapenemase producers. The sensitivity and specificity for detecting ESBL producers (n = 60) were 95% and 100% for the Rapid ESBL NDP test, 80% and 87% (after 30 min) and 92% and 83% (after 2 h) for the Rapid ESBL Screen, and 88% and 71% for the β-Lacta test, respectively. Varied and time-consuming detection (up to 2 h) of ESBLs by the Rapid ESBL Screen and concomitant and varied detection of producers of AmpC and several types of carbapenemases correspond to significant shortcomings of using the Rapid Screen ESBL and β-Lacta tests, respectively. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

[Human papillomavirus testing in cervical cancer screening at a public health service of Santiago, Chile].

PubMed

Terrazas, Solana; Ibáñez, Carolina; Lagos, Marcela; Poggi, Helena; Brañes, Jorge; Barriga, María Isabel; Cartagena, Jaime; Núñez, Felipe; González, Francisca; Cook, Paz; Van De Wyngard, Vanessa; Ferreccio, Catterina

2015-01-01

Molecular techniques for human papillomavirus (HPV) detection have a good performance as screening tests and could be included in cervical cancer early detection programs. We conducted a population-based trial comparing HPV detection and Papanicolaou as primary screening tests, in a public health service in Santiago, Chile. To describe the experience of implementing this new molecular test and present the main results of the study. Women aged 25 to 64 enrolled in three public health centers were invited to participate. In all women, samples were collected for Papanicolaou and HPV DNA testing, and naked-eye visual inspection of the cervix with acetic acid was performed. Women with any positive screening test were referred to the local area hospital for diagnostic confirmation with colposcopy and biopsy of suspicious lesions. Screening results were obtained for 8265 women, of whom 931 (11.3%) were positive to any test. The prevalence of cervical intraepithelial neoplasia grade 2 or worse (CIN2+) was 1.1%; nine women had invasive cervical cancer. Sensitivities for the detection of CIN2+ were 22.1% (95% confidence interval (CI) 16.4-29.2) for Papanicolaou and 92.7% (95% CI 84.4-96.8) for HPV testing; specificities were 98.9% (95% CI 98.7-99.0) and 92.0% (95% CI 91.4-92.6) respectively. This experience showed that the implementation of a molecular test for cervical cancer screening is not a major challenge in Chile: it was well accepted by both the health team and the participants, and it may improve the effectiveness of the screening program.

HPV Testing from Dried Urine Spots as a Tool for Cervical Cancer Screening in Low-Income Countries.

PubMed

Frati, Elena Rosanna; Martinelli, Marianna; Fasoli, Ester; Colzani, Daniela; Bianchi, Silvia; Binda, Sandro; Olivani, Pierfranco; Tanzi, Elisabetta

2015-01-01

Nowadays, several screening strategies are available to prevent cervical cancer, but inadequate resources, sociocultural barriers, and sampling issues impede their success in low-income countries. To overcome these issues, this study aimed to evaluate the performance of human papillomavirus (HPV) testing from dried urine spots (DUS). Eighty-eight urine samples (including 56 HPV DNA positive specimens) were spotted on filter paper, dried, and stored in paper-bags. HPV DNA was detected from the DUS after 1 week and 4 weeks of storage using a polymerase chain reaction (PCR) assay. The sensitivity, specificity, and concordance of the DUS-based HPV test were evaluated by comparing the results with those of HPV testing on fresh urine samples as the gold standard. The sensitivity of the test was 98.21% (95% CI: 90.56-99.68) for DUS stored for 1 week and 96.42% (95% CI: 87.88-99.01) for DUS stored for 4 weeks. The specificity was 100% (95% CI: 89.28-100) at both time points. The concordance between DUS and fresh urine HPV testing was "almost perfect" using the κ statistic. These preliminary data suggest that a DUS-based assay could bypass sociocultural barriers and sampling issues and therefore could be a suitable, effective tool for epidemiological surveillance and screening programs, especially in low-income countries.

HPV Testing from Dried Urine Spots as a Tool for Cervical Cancer Screening in Low-Income Countries

PubMed Central

Olivani, Pierfranco

2015-01-01

Nowadays, several screening strategies are available to prevent cervical cancer, but inadequate resources, sociocultural barriers, and sampling issues impede their success in low-income countries. To overcome these issues, this study aimed to evaluate the performance of human papillomavirus (HPV) testing from dried urine spots (DUS). Eighty-eight urine samples (including 56 HPV DNA positive specimens) were spotted on filter paper, dried, and stored in paper-bags. HPV DNA was detected from the DUS after 1 week and 4 weeks of storage using a polymerase chain reaction (PCR) assay. The sensitivity, specificity, and concordance of the DUS-based HPV test were evaluated by comparing the results with those of HPV testing on fresh urine samples as the gold standard. The sensitivity of the test was 98.21% (95% CI: 90.56–99.68) for DUS stored for 1 week and 96.42% (95% CI: 87.88–99.01) for DUS stored for 4 weeks. The specificity was 100% (95% CI: 89.28–100) at both time points. The concordance between DUS and fresh urine HPV testing was “almost perfect” using the κ statistic. These preliminary data suggest that a DUS-based assay could bypass sociocultural barriers and sampling issues and therefore could be a suitable, effective tool for epidemiological surveillance and screening programs, especially in low-income countries. PMID:26180790

Contrast-enhanced spectral mammography (CESM) versus MRI in the high-risk screening setting: patient preferences and attitudes.

PubMed

Phillips, Jordana; Miller, Matthew M; Mehta, Tejas S; Fein-Zachary, Valerie; Nathanson, Audrey; Hori, Wendy; Monahan-Earley, Rita; Slanetz, Priscilla J

Our study evaluates patient preferences toward screening CESM versus MRI. As part of a prospective study, high-risk patients had breast MRI and CESM. Patients completed an anonymous survey to evaluate preferences regarding the two modalities. 88% of participants completed the survey. 79% preferred CESM over MRI if the exams had equal sensitivity. 89% would be comfortable receiving contrast as part of an annual screening test. High-risk populations may accept CESM as a screening exam and may prefer it over screening MRI if ongoing trials demonstrate screening CESM to be clinically non-inferior MRI. Copyright © 2016 Elsevier Inc. All rights reserved.

Sensitivity of nested-PCR for plasmodium detection in pooled whole blood samples and its usefulness to blood donor screening in endemic areas.

PubMed

de Freitas, Daniel Roberto Coradi; Gomes, Luciano Teixeira; Fontes, Cor Jesus F; Tauil, Pedro Luiz; Pang, Lorrin W; Duarte, Elisabeth Carmen

2014-04-01

Transfusion-transmitted malaria is a severe disease with high fatality rate. Most Brazilian blood banks in the Amazon region perform malaria screening using microscopic examination (thick smears). Since low parasite concentrations are expected in asymptomatic blood donors a high sensitivity test should be used for donor screening. This study determined the sensitivity of a nested-PCR for plasmodium detection in pooled samples. We performed a one-stage criterion validation study with 21 positive samples pooled with samples from ten negative volunteer until three different concentrations were reached (0.33; 0.25; 0.20 parasites/μL - p/μL). Nested PCR was performed as described by Snounou et al. (1993). Sensitivities (and confidence intervals) were determined by stratum of final parasite concentration on the pooled samples. All samples with parasitemia values of 0.33 and 0.25 p/μL had 100% sensitivity (95%CI=86.3-100). One negative result was obtained from a sample with 0.20 p/μL sensitivity=95.2% (95%CI=76.2-99.9). Compared to parasitemia detectable under ideal conditions of thick smear, this nested-PCR in pooled sample was able to detect 40 times more parasites per microliter. Nested-PCR in pooled samples should be considered as a high sensitive alternative to thick smear for donor screening in blood banks at endemic regions. Local authorities need to assess cost:benefit advantages of this method compared to alternatives. Copyright © 2014 Elsevier Ltd. All rights reserved.

Evaluation of the GARD assay in a blind Cosmetics Europe study.

PubMed

Johansson, Henrik; Gradin, Robin; Forreryd, Andy; Agemark, Maria; Zeller, Kathrin; Johansson, Angelica; Larne, Olivia; van Vliet, Erwin; Borrebaeck, Carl; Lindstedt, Malin

2017-01-01

Chemical hypersensitivity is an immunological response towards foreign substances, commonly referred to as sensitizers, which gives rise primarily to the clinical symptoms known as allergic contact dermatitis. For the purpose of mitigating risks associated with consumer products, chemicals are screened for sensitizing effects. Historically, such predictive screenings have been performed using animal models. However, due to industrial and regulatory demand, animal models for the purpose of sensitization assessment are being replaced by non-animal testing methods, a global trend that is spreading across industries and market segments. To meet this demand, the Genomic Allergen Rapid Detection (GARD) assay was developed. GARD is a novel, cell-based assay that utilizes the innate recognition of xenobiotic substances by dendritic cells, as measured by a multivariate readout of genomic biomarkers. Following cellular stimulation, chemicals are classified as sensitizers or non-sensitizers based on induced transcriptional profiles. Recently, a number of non-animal methods were comparatively evaluated by Cosmetics Europe, using a coherent and blinded test panel of reference chemicals with human and local lymph node assay data, comprising a wide range of sensitizers and non-sensitizers. The outcome of the GARD assay is presented in this paper. It was demonstrated that GARD is a highly functional assay with a predictive performance of 83% in this Cosmetics Europe dataset. The average accumulated predictive accuracy of GARD across independent datasets was 86% for skin sensitization hazard.

QSAR models of human data can enrich or replace LLNA testing for human skin sensitization

PubMed Central

Alves, Vinicius M.; Capuzzi, Stephen J.; Muratov, Eugene; Braga, Rodolpho C.; Thornton, Thomas; Fourches, Denis; Strickland, Judy; Kleinstreuer, Nicole; Andrade, Carolina H.; Tropsha, Alexander

2016-01-01

Skin sensitization is a major environmental and occupational health hazard. Although many chemicals have been evaluated in humans, there have been no efforts to model these data to date. We have compiled, curated, analyzed, and compared the available human and LLNA data. Using these data, we have developed reliable computational models and applied them for virtual screening of chemical libraries to identify putative skin sensitizers. The overall concordance between murine LLNA and human skin sensitization responses for a set of 135 unique chemicals was low (R = 28-43%), although several chemical classes had high concordance. We have succeeded to develop predictive QSAR models of all available human data with the external correct classification rate of 71%. A consensus model integrating concordant QSAR predictions and LLNA results afforded a higher CCR of 82% but at the expense of the reduced external dataset coverage (52%). We used the developed QSAR models for virtual screening of CosIng database and identified 1061 putative skin sensitizers; for seventeen of these compounds, we found published evidence of their skin sensitization effects. Models reported herein provide more accurate alternative to LLNA testing for human skin sensitization assessment across diverse chemical data. In addition, they can also be used to guide the structural optimization of toxic compounds to reduce their skin sensitization potential. PMID:28630595

Accuracy of self-reports of fecal occult blood tests and test results among individuals in the carpentry trade.

PubMed

Lipkus, Isaac M; Samsa, Gregory P; Dement, John; Skinner, Celette Sugg; Green, La Sonya G; Pompeii, Lisa; Ransohoff, David F

2003-11-01

Inaccuracy in self-reports of colorectal cancer (CRC) screening procedures (e.g., over- or underreporting) may interfere with individuals adhering to appropriate screening intervals, and can blur the true effects of physician recommendations to screen and the effects of interventions designed to promote screening. We assessed accuracy of self-report of having a fecal occult blood test (FOBT) within a 1-year window based on receipt of FOBT kits among individuals aged 50 and older in the carpentry trade (N = 658) who were off-schedule for having had a FOBT. Indices of evaluating accuracy of self-reports (concordance, specificity, false-positive and false-negative rates) were calculated relative to receipt of a mailed FOBT. Among those who mailed a completed FOBT, we assessed accuracy of reporting the test result. Participants underestimated having performed a FOBT (false-negative rate of 44%). Accuracy was unrelated to perceptions of getting or worrying about CRC or family history. Self-reports of having a negative FOBT result more consistently matched the laboratory result (specificity 98%) than having a positive test result (sensitivity 63%). Contrary to other findings, participants under- rather than over reported FOBT screening. Results suggest greater efforts are needed to enhance accurate recall of FOBT screening.

The use of the Micral-Test strip to identify the presence of microalbuminuria in people with insulin dependent diabetes mellitus (IDDM) participating in the EUCLID study.

PubMed

Webb, D J; Newman, D J; Chaturvedi, N; Fuller, J H

1996-03-01

In IDDM, microalbuminuria (urinary albumin excretion rate (AER) of 20-200 micrograms/min) is a predictor of persistent proteinuria and diabetic nephropathy. Early intervention may prevent or reduce the rate of progression of renal complications. The Micral-Test strip can be used to establish a semi-quantitative estimate of AER. We assessed the field performance of the Micral-Test strip in detecting microalbuminuria in the EUCLID study, an European wide, 18 centre study of 530 IDDM participants, aged 20 to 59 years. People with macroalbuminuria were excluded. On entry, all participants had albumin concentrations from two overnight urine collections measured by a central laboratory, and the corresponding Micral-Test performed on the two collections locally. a cut off of > or = mg/l albumin from the first Micral-Test, to detect a centrally measured albumin concentration > or = 20 mg/l, yielded 29 (5.8%) false negative results and 58 (11.6%) false positive results (sensitivity 70%, specificity 87%). The mean AER, from two collections, was compared with the corresponding 'pooled' Micral-Test results (mean of the two readings). Receiver Operating Characteristic (ROC) curves were used to assess if there was a suitable 'pooled' Micral-Test result for screening microalbuminuria. A 'pooled' Micral-Test result (> or = 15 mg/l) was used to detect mean AER > or = 20 micrograms/min (sensitivity 78%, specificity 77%). This 'pooled cut-off' had already been used for screening on to the study and led to an over-estimate (154 vs. 77) of the true number of microalbuminuric participants on the study. In conclusion, our findings suggest that the Micral-Test strip is not an effective screening tool for microalbuminuria, using the 'pooled' result from two measurements did not improve the sensitivity of the test.

Colorectal Cancer: Cost-effectiveness of Colonoscopy versus CT Colonography Screening with Participation Rates and Costs.

PubMed

van der Meulen, Miriam P; Lansdorp-Vogelaar, Iris; Goede, S Lucas; Kuipers, Ernst J; Dekker, Evelien; Stoker, Jaap; van Ballegooijen, Marjolein

2018-06-01

Purpose To compare the cost-effectiveness of computed tomographic (CT) colonography and colonoscopy screening by using data on unit costs and participation rates from a randomized controlled screening trial in a dedicated screening setting. Materials and Methods Observed participation rates and screening costs from the Colonoscopy or Colonography for Screening, or COCOS, trial were used in a microsimulation model to estimate costs and quality-adjusted life-years (QALYs) gained with colonoscopy and CT colonography screening. For both tests, the authors determined optimal age range and screening interval combinations assuming a 100% participation rate. Assuming observed participation for these combinations, the cost-effectiveness of both tests was compared. Extracolonic findings were not included because long-term follow-up data are lacking. Results The participation rates for colonoscopy and CT colonography were 21.5% (1276 of 5924 invitees) and 33.6% (982 of 2920 invitees), respectively. Colonoscopy was more cost-effective in the screening strategies with one or two lifetime screenings, whereas CT colonography was more cost-effective in strategies with more lifetime screenings. CT colonography was the preferred test for willingness-to-pay-thresholds of €3200 per QALY gained and higher, which is lower than the Dutch willingness-to-pay threshold of €20 000. With equal participation, colonoscopy was the preferred test independent of willingness-to-pay thresholds. The findings were robust for most of the sensitivity analyses, except with regard to relative screening costs and subsequent participation. Conclusion Because of the higher participation rates, CT colonography screening for colorectal cancer is more cost-effective than colonoscopy screening. The implementation of CT colonography screening requires previous satisfactory resolution to the question as to how best to deal with extracolonic findings. © RSNA, 2018 Online supplemental material is available for this article.

Hearing Screening of High-Risk Newborns with Brainstem Auditory Evoked Potentials: A Follow-Up Study.

ERIC Educational Resources Information Center

Shannon, Dorothy A.; And Others

1984-01-01

The brainstem auditory evoked potential (BAEP) was evaluated as a hearing screening test in 168 high-risk newborns. The BAEP was found to be a sensitive procedure for the early identification of hearing-impaired newborns. However, the yield of significant hearing abnormalities was less than predicted in other studies using BAEP. (Author/CL)

Accuracy and Feasibility of an Android-Based Digital Assessment Tool for Post Stroke Visual Disorders-The StrokeVision App.

PubMed

Quinn, Terence J; Livingstone, Iain; Weir, Alexander; Shaw, Robert; Breckenridge, Andrew; McAlpine, Christine; Tarbert, Claire M

2018-01-01

Visual impairment affects up to 70% of stroke survivors. We designed an app (StrokeVision) to facilitate screening for common post stroke visual issues (acuity, visual fields, and visual inattention). We sought to describe the test time, feasibility, acceptability, and accuracy of our app-based digital visual assessments against (a) current methods used for bedside screening and (b) gold standard measures. Patients were prospectively recruited from acute stroke settings. Index tests were app-based assessments of fields and inattention performed by a trained researcher. We compared against usual clinical screening practice of visual fields to confrontation, including inattention assessment (simultaneous stimuli). We also compared app to gold standard assessments of formal kinetic perimetry (Goldman or Octopus Visual Field Assessment); and pencil and paper-based tests of inattention (Albert's, Star Cancelation, and Line Bisection). Results of inattention and field tests were adjudicated by a specialist Neuro-ophthalmologist. All assessors were masked to each other's results. Participants and assessors graded acceptability using a bespoke scale that ranged from 0 (completely unacceptable) to 10 (perfect acceptability). Of 48 stroke survivors recruited, the complete battery of index and reference tests for fields was successfully completed in 45. Similar acceptability scores were observed for app-based [assessor median score 10 (IQR: 9-10); patient 9 (IQR: 8-10)] and traditional bedside testing [assessor 10 (IQR: 9-10); patient 10 (IQR: 9-10)]. Median test time was longer for app-based testing [combined time to completion of all digital tests 420 s (IQR: 390-588)] when compared with conventional bedside testing [70 s, (IQR: 40-70)], but shorter than gold standard testing [1,260 s, (IQR: 1005-1,620)]. Compared with gold standard assessments, usual screening practice demonstrated 79% sensitivity and 82% specificity for detection of a stroke-related field defect. This compares with 79% sensitivity and 88% specificity for StrokeVision digital assessment. StrokeVision shows promise as a screening tool for visual complications in the acute phase of stroke. The app is at least as good as usual screening and offers other functionality that may make it attractive for use in acute stroke. https://ClinicalTrials.gov/ct2/show/NCT02539381.

Development of a computer-based automated pure tone hearing screening device: a preliminary clinical trial.

PubMed

Gan, Kok Beng; Azeez, Dhifaf; Umat, Cila; Ali, Mohd Alauddin Mohd; Wahab, Noor Alaudin Abdul; Mukari, Siti Zamratol Mai-Sarah

2012-10-01

Hearing screening is important for the early detection of hearing loss. The requirements of specialized equipment, skilled personnel, and quiet environments for valid screening results limit its application in schools and health clinics. This study aimed to develop an automated hearing screening kit (auto-kit) with the capability of realtime noise level monitoring to ensure that the screening is performed in an environment that conforms to the standard. The auto-kit consists of a laptop, a 24-bit resolution sound card, headphones, a microphone, and a graphical user interface, which is calibrated according to the American National Standards Institute S3.6-2004 standard. The auto-kit can present four test tones (500, 1000, 2000, and 4000 Hz) at 25 or 40 dB HL screening cut-off level. The clinical results at 40 dB HL screening cut-off level showed that the auto-kit has a sensitivity of 92.5% and a specificity of 75.0%. Because the 500 Hz test tone is not included in the standard hearing screening procedure, it can be excluded from the auto-kit test procedure. The exclusion of 500 Hz test tone improved the specificity of the auto-kit from 75.0% to 92.3%, which suggests that the auto-kit could be a valid hearing screening device. In conclusion, the auto-kit may be a valuable hearing screening tool, especially in countries where resources are limited.

Sensitivity and specificity of the subcutaneous implantable cardioverter defibrillator pre-implant screening tool.

PubMed

Zeb, Mehmood; Curzen, Nick; Allavatam, Venugopal; Wilson, David; Yue, Arthur; Roberts, Paul; Morgan, John

2015-09-15

The sensitivity and specificity of the subcutaneous implantable cardioverter defibrillator (S-ICD) pre-implant screening tool required clinical evaluation. Bipolar vectors were derived from electrodes positioned at locations similar to those employed for S-ICD sensing and pre-implant screening electrodes, and recordings collected through 80-electrode PRIME®-ECGs, in six different postures, from 40 subjects (10 healthy controls, and 30 patients with complex congenital heart disease (CCHD); 10 with Tetralogy of Fallot (TOF), 10 with single ventricle physiology (SVP), and 10 with transposition of great arteries (TGA)). The resulting vectors were analysed using the S-ICD pre-implant screening tool (Boston Scientific) and processed through the sensing algorithm of S-ICD (Boston Scientific). The data were then evaluated using 2 × 2 contingency tables. Fisher exact and McNemar tests were used for a comparison of the different categories of CCHD, and p < 0.05 vs. controls considered to be statistically significant. 57% of patients were male, mean age of 36.3 years. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of the S-ICD screening tool were 95%, 79%, 59% and 98%, respectively, for controls, and 84%, 79%, 76% and 86%, respectively, in patients with CCHD (p = 0.0001). The S-ICD screening tool was comparatively more sensitive in normal controls but less specific in both CCHD patients and controls; a possible explanation for the reported high incidence of inappropriate S-ICD shocks. Thus, we propose a pre-implant screening device using the S-ICD sensing algorithm to minimise false exclusion and selection, and hence minimise potentially inappropriate shocks. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Effect of facility background gases on internal erosion of the 30-cm Hg ion thruster

NASA Technical Reports Server (NTRS)

Rawlin, V. K.; Mantenieks, M. A.

1978-01-01

Sputtering erosion of the upstream side of the molybdenum screen grid by discharge chamber ions in mercury bombardment thrusters was considered. Data which revealed that the screen grid erosion was very sensitive to the partial pressure of certain background gases in the space simulation vacuum facility were presented along with results of tests conducted to evaluate this effect. It is shown from estimates of the screen grid erosion in space that adequate lifetime for proposed missions exists.

Noninvasive Prenatal Screening for Genetic Diseases Using Massively Parallel Sequencing of Maternal Plasma DNA

PubMed Central

Chitty, Lyn S.; Lo, Y. M. Dennis

2015-01-01

The identification of cell-free fetal DNA (cffDNA) in maternal plasma in 1997 heralded the most significant change in obstetric care for decades, with the advent of safer screening and diagnosis based on analysis of maternal blood. Here, we describe how the technological advances offered by next-generation sequencing have allowed for the development of a highly sensitive screening test for aneuploidies as well as definitive prenatal molecular diagnosis for some monogenic disorders. PMID:26187875

False-negative syphilis treponemal enzyme immunoassay results in an HIV-infected case-patient.

PubMed

Katz, Alan R; Komeya, Alan Y; Tomas, Juval E

2017-06-01

We present a case report of a false-negative syphilis treponemal enzyme immunoassay test result in an HIV-infected male. While treponemal tests are widely considered to be more sensitive and specific than non-treponemal tests, our findings point to potential challenges using the reverse sequence syphilis screening algorithm.

Epistasis and the sensitivity of phenotypic screens for beta thalassaemia.

PubMed

Penman, Bridget S; Gupta, Sunetra; Weatherall, David J

2015-04-01

Genetic disorders of haemoglobin, particularly the sickle cell diseases and the alpha and beta thalassaemias, are the commonest inherited disorders worldwide. The majority of affected births occur in low-income and lower-middle income countries. Screening programmes are a vital tool to counter these haemoglobinopathies by: (i) identifying individual carriers and allowing them to make informed reproductive choices, and (ii) generating population level gene-frequency estimates, to help ensure the optimal allocation of public health resources. For both of these functions it is vital that the screen performed is suitably sensitive. One popular first-stage screening option to detect carriers of beta thalassaemia in low-income countries is the One Tube Osmotic Fragility Test (OTOFT). Here we introduce a population genetic framework within which to quantify the likely sensitivity and specificity of the OTOFT in different epidemiological contexts. We demonstrate that interactions between the carrier states for beta thalassaemia and alpha thalassaemia, glucose-6-phosphate dehydrogenase deficiency and Southeast Asian Ovalocytosis have the potential to reduce the sensitivity of OTOFTs for beta thalassaemia heterozygosity to below 70%. Our results therefore caution against the widespread application of OTOFTs in regions where these erythrocyte variants co-occur. © 2014 The Authors. British Journal of Haematology published by John Wiley & Sons Ltd.

Screening test for neutralizing antibodies against yellow fever virus, based on a flavivirus pseudotype.

PubMed

Mercier-Delarue, Séverine; Durier, Christine; Colin de Verdière, Nathalie; Poveda, Jean-Dominique; Meiffrédy, Vincent; Fernandez Garcia, Maria Dolores; Lastère, Stéphane; Césaire, Raymond; Manuggera, Jean-Claude; Molina, Jean-Michel; Amara, Ali; Simon, François

2017-01-01

Given the possibility of yellow fever virus reintroduction in epidemiologically receptive geographic areas, the risk of vaccine supply disruption is a serious issue. New strategies to reduce the doses of injected vaccines should be evaluated very carefully in terms of immunogenicity. The plaque reduction test for the determination of neutralizing antibodies (PRNT) is particularly time-consuming and requires the use of a confinement laboratory. We have developed a new test based on the use of a non-infectious pseudovirus (WN/YF17D). The presence of a reporter gene allows sensitive determination of neutralizing antibodies by flow cytometry. This WN/YF17D test was as sensitive as PRNT for the follow-up of yellow fever vaccinees. Both tests lacked specificity with sera from patients hospitalized for acute Dengue virus infection. Conversely, both assays were strictly negative in adults never exposed to flavivirus infection or vaccination, and in patients sampled some time after acute Dengue infection. This WN/YF17D test will be particularly useful for large epidemiological studies and for screening for neutralizing antibodies against yellow fever virus.

Performance of the CareStart Glucose-6-Phosphate Dehydrogenase (G6PD) Rapid Diagnostic Test in Gressier, Haiti

PubMed Central

von Fricken, Michael E.; Weppelmann, Thomas A.; Eaton, Will T.; Masse, Roseline; Beau de Rochars, Madsen V. E.; Okech, Bernard A.

2014-01-01

Administering primaquine (PQ) to treat malaria patients with glucose-6-phosphate dehydrogenase (G6PD) deficiency can pose a serious risk of drug-induced hemolysis (DIH). New easy to use point-of-care rapid diagnostic tests are being developed as an alternative to labor-intensive spectrophotometric methods, but they require field testing before they can be used at scale. This study screened 456 participants in Gressier, Haiti using the Access Bio CareStart qualitative G6PD rapid detection test compared with the laboratory-based Trinity Biotech quantitative spectrophotometric assay. Findings suggest that the CareStart test was 90% sensitive for detecting individuals with severe deficiency and 84.8% sensitive for detecting individuals with moderate and severe deficiency compared with the Trinity Biotech assay. A high negative predictive value of 98.2% indicates excellent performance in determining those patients able to take PQ safely. The CareStart G6PD test holds much value for screening malaria patients to determine eligibility for PQ therapy. PMID:24778197

Performance of the CareStart glucose-6-phosphate dehydrogenase (G6PD) rapid diagnostic test in Gressier, Haiti.

PubMed

von Fricken, Michael E; Weppelmann, Thomas A; Eaton, Will T; Masse, Roseline; Beau de Rochars, Madsen V E; Okech, Bernard A

2014-07-01

Administering primaquine (PQ) to treat malaria patients with glucose-6-phosphate dehydrogenase (G6PD) deficiency can pose a serious risk of drug-induced hemolysis (DIH). New easy to use point-of-care rapid diagnostic tests are being developed as an alternative to labor-intensive spectrophotometric methods, but they require field testing before they can be used at scale. This study screened 456 participants in Gressier, Haiti using the Access Bio CareStart qualitative G6PD rapid detection test compared with the laboratory-based Trinity Biotech quantitative spectrophotometric assay. Findings suggest that the CareStart test was 90% sensitive for detecting individuals with severe deficiency and 84.8% sensitive for detecting individuals with moderate and severe deficiency compared with the Trinity Biotech assay. A high negative predictive value of 98.2% indicates excellent performance in determining those patients able to take PQ safely. The CareStart G6PD test holds much value for screening malaria patients to determine eligibility for PQ therapy. © The American Society of Tropical Medicine and Hygiene.

Are medication restrictions before FOBT necessary?

PubMed Central

Konrad, Gerald; Katz, Alan

2012-01-01

Abstract Objective To determine whether medication interventions enhance the sensitivity and specificity of guaiac-based fecal occult blood testing (FOBT) when screening for colorectal cancer (CRC). Data sources We searched PubMed-MEDLINE, CINAHL, and the Cochrane databases using the MeSH headings occult blood, feces/analysis, and guaiac/analysis, linking them to variations of anticoagulants, heparin, warfarin, iron, aspirin, nonsteroidal anti-inflammatory drugs (NSAIDs), clopidogrel, cyclooxygenase-2 inhibitors, and ascorbic acid (vitamin C). Study selections were limited to English studies involving humans. Study selection All resulting titles and abstracts were reviewed for studies that included manipulation of medications associated with guaiac-based FOBT. If the study’s relevance was unclear from the abstract, the full article was reviewed. The search resulted in 31 pertinent studies. Synthesis No studies addressed the effects of medication interventions on the sensitivity or specificity of FOBT screening. Randomized controlled trials, however, showed no increase in the rate of positive results among those taking NSAIDs. The literature is mixed regarding the effect of NSAIDs on the positive predictive value of a positive FOBT result, although no change in positive predictive value has been shown for warfarin. Iron will not affect FOBT results in vivo. Ascorbic acid might inhibit positive FOBT results both in vitro and in vivo, but it has not been studied in screening populations. Conclusion Studies evaluating the effects of medication intervention on FOBT screening for CRC are limited by their lower quality and because they do not address sensitivity and specificity. Available evidence, however, does not suggest a benefit from withholding NSAIDs, anticoagulant medications, or iron during the screening period. These recommendations should be abandoned in order to maximize adherence to screening. Positive FOBT results obtained among patients taking these medications deserve full evaluation for CRC. Until further studies clarify the effect of ascorbic acid on FOBT screening, withholding this medication before testing seems prudent. PMID:22972722

Screening for chlamydial infection.

PubMed

Nelson, H D; Helfand, M

2001-04-01

To examine data on the effectiveness of screening for chlamydial infection by a physician or other health care professional. Specifically, we examine the evidence that early treatment of chlamydial infection improves health outcomes, as well as evidence of the effectiveness of screening strategies in nonpregnant women, pregnant women, and men, and the accuracy of tests used for screening. This review updates the literature since the last recommendation of the U.S. Preventive Services Task Force published in 1996. We searched the topic of chlamydia in the MEDLINE, HealthSTAR, and Cochrane Library databases from January 1994 to July 2000, supplemented by reference lists of relevant articles and from experts in the field. Articles published prior to 1994 and research abstracts were cited if particularly important to the key questions or to the interpretation of included articles. A single reader reviewed all English abstracts. Articles were selected for full review if they were about Chlamydia trachomatis genitourinary infections in nonpregnant women, pregnant women, or men and were relevant to key questions in the analytic framework. Investigators read the full-text version of the retrieved articles and applied additional eligibility criteria. For all topics, we excluded articles if they did not provide sufficient information to determine the methods for selecting subjects and for analyzing data. We systematically reviewed three types of studies about screening in nonpregnant women that relate to three key questions: (1) studies about the effectiveness of screening programs in reducing prevalence rates of infection, (2) studies about risk factors for chlamydial infection in women, and (3) studies about chlamydial screening tests in women. Our search found too few studies on pregnant women to systematically review, although pertinent studies are described. We systematically reviewed two types of studies about screening in men: (1) studies about prevalence rates and risk factors for chlamydial infection in men and (2) studies about chlamydial screening tests in men. Nonpregnant women. The results of a randomized controlled trial conducted in a large health maintenance organization indicate that screening women selected by a set of risk factors reduces the incidence of pelvic inflammatory disease (PID) over a 1-year period. Changes in population prevalence rates have not been well documented because few studies have employed a representative population sample. Age continues to be the best predictor of chlamydial infection in women, with most studies evaluating cut-offs at age younger than 25 years. Other risk factors may be useful predictors, but these are likely to be population specific. To determine the accuracy of screening tests for women, we retrieved and critically reviewed 34 articles on test performance. Results indicate that endocervical swab specimens and first-void urine specimens have similar performance when using DNA amplification tests and have better sensitivity than endocervical culture. Recurrent chlamydial infections in women have been associated with increased risks for PID and ectopic pregnancies. Pregnant women. The Second Task Force recommendations for screening pregnant women were based on two major studies demonstrating improved pregnancy outcomes following treatment of chlamydial infection. We identified no recent studies on this topic in our literature search. Very few studies describe risk factors for chlamydial infection in pregnant women. Nonculture testing techniques appear to perform well in pregnant women, although studies are limited. Men. No studies described the effectiveness of screening or early treatment for men in reducing transmission to women or in preventing acute infections or complications in men. Studies of prevalence rates and risk factors for chlamydial infection in men are limited. Age lower than 25 years is the strongest known risk factor cited so far. Results of urethral swab specimens compared to first-void urine specimens were similar for DNA amplification tests. DNA amplification techniques are more sensitive than culture. Screening women for Chlamydia trachomatis reduces the incidence of PID, and it is associated with reductions in prevalence of infection in uncontrolled studies. No studies were found to determine whether screening asymptomatic men would reduce transmission or prevent acute infections or complications. Age is the strongest risk factor for men and women. A variety of tests can detect chlamydial infection with acceptable sensitivity and specificity, including new DNA amplification tests that use either endocervical swabs in women, urethral swabs in men, or first-void urine specimens from men and women.

The validity of self-reported cancer screening history and the role of social disadvantage in Ontario, Canada.

PubMed

Lofters, Aisha; Vahabi, Mandana; Glazier, Richard H

2015-01-29

Self-report may not be an accurate method of determining cervical, breast and colorectal cancer screening rates due to recall, acquiescence and social desirability biases, particularly for certain sociodemographic groups. Therefore, the aims of this study were to determine the validity of self-report of cancer screening in Ontario, Canada, both for people in the general population and for socially disadvantaged groups based on immigrant status, ethnicity, education, income, language ability, self-rated health, employment status, age category (for cervical cancer screening), and gender (for fecal occult blood testing). We linked multiple data sources for this study, including the Canadian Community Health Survey and provincial-level health databases. Using administrative data as our gold standard, we calculated validity measures for self-report (i.e. sensitivity, specificity, positive and negative likelihood ratios, positive and negative predictive values), calculated report-to-record ratios, and conducted a multivariable regression analysis to determine which characteristics were independently associated with over-reporting of screening. Specificity was less than 70% overall and for all subgroups for cervical and breast cancer screening, and sensitivity was lower than 80% overall and for all subgroups for fecal occult blood testing FOBT. Report-to-record ratios were persistently significantly greater than 1 across all cancer screening types, highest for the FOBT group: 1.246 [1.189-1.306]. Regression analyses showed no consistent patterns, but sociodemographic characteristics were associated with over-reporting for each screening type. We have found that in Ontario, as in other jurisdictions, there is a pervasive tendency for people to over-report their cancer screening histories. Sociodemographic status also appears to influence over-reporting. Public health practitioners and policymakers need to be aware of the limitations of self-report and adjust their methods and interpretations accordingly.

Screening for chronic kidney disease in Canadian indigenous peoples is cost-effective.

PubMed

Ferguson, Thomas W; Tangri, Navdeep; Tan, Zhi; James, Matthew T; Lavallee, Barry D A; Chartrand, Caroline D; McLeod, Lorraine L; Dart, Allison B; Rigatto, Claudio; Komenda, Paul V J

2017-07-01

Canadian indigenous (First Nations) have rates of kidney failure that are 2- to 4-fold higher than the non-indigenous general Canadian population. As such, a strategy of targeted screening and treatment for CKD may be cost-effective in this population. Our objective was to assess the cost utility of screening and subsequent treatment for CKD in rural Canadian indigenous adults by both estimated glomerular filtration rate and the urine albumin-to-creatinine ratio. A decision analytic Markov model was constructed comparing the screening and treatment strategy to usual care. Primary outcomes were presented as incremental cost-effectiveness ratios (ICERs) presented as a cost per quality-adjusted life-year (QALY). Screening for CKD was associated with an ICER of $23,700/QALY in comparison to usual care. Restricting the model to screening in communities accessed only by air travel (CKD prevalence 34.4%), this ratio fell to $7,790/QALY. In road accessible communities (CKD prevalence 17.6%) the ICER was $52,480/QALY. The model was robust to changes in influential variables when tested in univariate sensitivity analyses. Probabilistic sensitivity analysis found 72% of simulations to be cost-effective at a $50,000/QALY threshold and 93% of simulations to be cost-effective at a $100,000/QALY threshold. Thus, targeted screening and treatment for CKD using point-of-care testing equipment in rural Canadian indigenous populations is cost-effective, particularly in remote air access-only communities with the highest risk of CKD and kidney failure. Evaluation of targeted screening initiatives with cluster randomized controlled trials and integration of screening into routine clinical visits in communities with the highest risk is recommended. Copyright © 2017 International Society of Nephrology. Published by Elsevier Inc. All rights reserved.

An improvement of LLNA:DA to assess the skin sensitization potential of chemicals.

PubMed

Zhang, Hongwei; Shi, Ying; Wang, Chao; Zhao, Kangfeng; Zhang, Shaoping; Wei, Lan; Dong, Li; Gu, Wen; Xu, Yongjun; Ruan, Hongjie; Zhi, Hong; Yang, Xiaoyan

2017-01-01

We developed a modified local lymph node assay based on ATP (LLNA:DA), termed the Two-Stage LLNA:DA, to further reduce the animal numbers in the identification of sensitizers. In the Two-Stage LLNA:DA procedure, 13 chemicals ranging from non-sensitizers to extreme sensitizers were selected. The first stage used reduced LLNA:DA (rLLNA:DA) to screen out sensitive chemicals. The second stage used LLNA:DA based on OECD 442 (A) to classify those potential sensitizers screened out in the first stage. In the first stage, the SIs of the methyl methacrylate, salicylic acid, methyl salicylate, ethyl salicylate, isopropanol and propanediol were below 1.8 and need not to be tested in the second step. Others continued to be tested by LLNA:DA. In the second stage, sodium lauryl sulphate and xylene were classified as weak sensitizers. a-hexyl cinnamic aldehyde and eugenol were moderate sensitizers. Benzalkonium chloride and glyoxal were strong sensitizers, and phthalic anhydride was an extreme sensitizer. The 9/9, 11/12, 10/11, and 8/13 (positive or negative only) categories of the Two-Stage LLNA:DA were consistent with those from the other methods (LLNA, LLNA:DA, GPMT/BT and HMT/HPTA), suggesting that Two-Stage LLNA:DA have a high coincidence rate with reported data. In conclusion, The Two-Stage LLNA:DA is in line with the "3R" rules, and can be a modification of LLNA:DA but needs more study.

The Cross-Cultural Dementia Screening (CCD): A new neuropsychological screening instrument for dementia in elderly immigrants.

PubMed

Goudsmit, Miriam; Uysal-Bozkir, Özgül; Parlevliet, Juliette L; van Campen, Jos P C M; de Rooij, Sophia E; Schmand, Ben

2017-03-01

Currently, approximately 3.9% of the European population are non-EU citizens, and a large part of these people are from "non-Western" societies, such as Turkey and Morocco. For various reasons, the incidence of dementia in this group is expected to increase. However, cognitive testing is challenging due to language barriers and low education and/or illiteracy. The newly developed Cross-Cultural Dementia Screening (CCD) can be administered without an interpreter. It contains three subtests that assess memory, mental speed, and executive function. We hypothesized the CCD to be a culture-fair test that could discriminate between demented patients and cognitively healthy controls. To test this hypothesis, 54 patients who had probable dementia were recruited via memory clinics. Controls (N = 1625) were recruited via their general practitioners. All patients and controls were aged 55 years and older and of six different self-defined ethnicities (Dutch, Turkish, Moroccan-Arabic, Moroccan-Berber, Surinamese-Creole, and Surinamese-Hindustani). Exclusion criteria included current or previous conditions that affect cognitive functioning. There were performance differences between the ethnic groups, but these disappeared after correcting for age and education differences between the groups, which supports our central hypothesis that the CCD is a culture-fair test. Receiver-operating characteristic (ROC) and logistic regression analyses showed that the CCD has high predictive validity for dementia (sensitivity: 85%; specificity: 89%). The CCD is a sensitive and culture-fair neuropsychological instrument for dementia screening in low-educated immigrant populations.

Health economic evaluation of plasma oxysterol screening in the diagnosis of Niemann-Pick Type C disease among intellectually disabled using discrete event simulation.

PubMed

van Karnebeek, Clara D M; Mohammadi, Tima; Tsao, Nicole; Sinclair, Graham; Sirrs, Sandra; Stockler, Sylvia; Marra, Carlo

2015-02-01

Recently a less invasive method of screening and diagnosing Niemann-Pick C (NP-C) disease has emerged. This approach involves the use of a metabolic screening test (oxysterol assay) instead of the current practice of clinical assessment of patients suspected of NP-C (review of medical history, family history and clinical examination for the signs and symptoms). Our objective is to compare costs and outcomes of plasma oxysterol screening versus current practice in diagnosis of NP-C disease among intellectually disabled (ID) patients using decision-analytic methods. A discrete event simulation model was conducted to follow ID patients through the diagnosis and treatment of NP-C, forecast the costs and effectiveness for a cohort of ID patients and compare the outcomes and costs in two different arms of the model: plasma oxysterol screening and routine diagnosis procedure (anno 2013) over 5 years of follow up. Data from published sources and clinical trials were used in simulation model. Unit costs and quality-adjusted life-years (QALYs) were discounted at a 3% annual rate in the base case analysis. Deterministic and probabilistic sensitivity analyses were conducted. The outcomes of the base case model showed that using plasma oxysterol screening for diagnosis of NP-C disease among ID patients is a dominant strategy. It would result in lower total cost and would slightly improve patients' quality of life. The average amount of cost saving was $3642 CAD and the incremental QALYs per each individual ID patient in oxysterol screening arm versus current practice of diagnosis NP-C was 0.0022 QALYs. Results of sensitivity analysis demonstrated robustness of the outcomes over the wide range of changes in model inputs. Whilst acknowledging the limitations of this study, we conclude that screening ID children and adolescents with oxysterol tests compared to current practice for the diagnosis of NP-C is a dominant strategy with clinical and economic benefits. The less costly, more sensitive and specific oxysterol test has potential to save costs to the healthcare system while improving patients' quality of life and may be considered as a routine tool in the NP-C diagnosis armamentarium for ID. Further research is needed to elucidate its effectiveness in patients presenting characteristics other than ID in childhood and adolescence. Copyright © 2014 Elsevier Inc. All rights reserved.

Gastric adenocarcinoma screening and prevention in the era of new biomarker and endoscopic technologies: a cost-effectiveness analysis.

PubMed

Yeh, Jennifer M; Hur, Chin; Ward, Zachary; Schrag, Deborah; Goldie, Sue J

2016-04-01

To estimate the cost-effectiveness of noncardia gastric adenocarcinoma (NCGA) screening strategies based on new biomarker and endoscopic technologies. Using an intestinal-type NCGA microsimulation model, we evaluated the following one-time screening strategies for US men: (1) serum pepsinogen to detect gastric atrophy (with endoscopic follow-up of positive screen results), (2) endoscopic screening to detect dysplasia and asymptomatic cancer (with endoscopic mucosal resection (EMR) treatment for detected lesions) and (3) Helicobacter pylori screening and treatment. Screening performance, treatment effectiveness, cancer and cost data were based on published literature and databases. Subgroups included current, former and never smokers. Outcomes included lifetime cancer risk and incremental cost-effectiveness ratios (ICERs), expressed as cost per quality-adjusted-life-year (QALY) gained. Screening the general population at age 50 years reduced the lifetime intestinal-type NCGA risk (0.24%) by 26.4% with serum pepsinogen screening, 21.2% with endoscopy and EMR and 0.2% with H. pylori screening/treatment. Targeting current smokers reduced the lifetime risk (0.35%) by 30.8%, 25.5%, and 0.1%, respectively. For all subgroups, serum pepsinogen screening was more effective and more cost-effective than all other strategies, although its ICER varied from $76,000/QALY (current smokers) to $105,400/QALY (general population). Results were sensitive to H. pylori prevalence, screen age and serum pepsinogen test sensitivity. Probabilistic sensitivity analysis found that at a $100,000/QALY willingness-to-pay threshold, the probability that serum pepsinogen screening was preferred was 0.97 for current smokers. Although not warranted for the general population, targeting high-risk smokers for serum pepsinogen screening may be a cost-effective strategy to reduce intestinal-type NCGA mortality. 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/

Classification and virtual screening of androgen receptor antagonists.

PubMed

Li, Jiazhong; Gramatica, Paola

2010-05-24

Computational tools, such as quantitative structure-activity relationship (QSAR), are highly useful as screening support for prioritization of substances of very high concern (SVHC). From the practical point of view, QSAR models should be effective to pick out more active rather than inactive compounds, expressed as sensitivity in classification works. This research investigates the classification of a big data set of endocrine-disrupting chemicals (EDCs)-androgen receptor (AR) antagonists, mainly aiming to improve the external sensitivity and to screen for potential AR binders. The kNN, lazy IB1, and ADTree methods and the consensus approach were used to build different models, which improve the sensitivity on external chemicals from 57.1% (literature) to 76.4%. Additionally, the models' predictive abilities were further validated on a blind collected data set (sensitivity: 85.7%). Then the proposed classifiers were used: (i) to distinguish a set of AR binders into antagonists and agonists; (ii) to screen a combined estrogen receptor binder database to find out possible chemicals that can bind to both AR and ER; and (iii) to virtually screen our in-house environmental chemical database. The in silico screening results suggest: (i) that some compounds can affect the normal endocrine system through a complex mechanism binding both to ER and AR; (ii) new EDCs, which are nonER binders, but can in silico bind to AR, are recognized; and (iii) about 20% of compounds in a big data set of environmental chemicals are predicted as new AR antagonists. The priority should be given to them to experimentally test the binding activities with AR.

Sensitivity and specificity of a two-question screening tool for depression in a specialist palliative care unit.

PubMed

Payne, Ann; Barry, Sandra; Creedon, Brian; Stone, Carol; Sweeney, Catherine; O' Brien, Tony; O' Sullivan, Kathleen

2007-04-01

The primary objective in this study is to determine the sensitivity and specificity of a two-item screening interview for depression versus the formal psychiatric interview, in the setting of a specialist palliative in-patient unit so that we may identify those individuals suffering from depressive disorder and therefore optimise their management in this often-complex population. A prospective sample of consecutive admissions (n = 167) consented to partake in the study, and the screening interview was asked separately to the formal psychiatric interview. The two-item questionnaire, achieved a sensitivity of 90.7% (95% CI 76.9-97.0) but a lower specificity of 67.7% (95% CI 58.7-75.7). The false positive rate was 32.3% (95% CI 24.3-41.3), but the false negative rate was found to be a low 9.3% (95% CI 3.0-23.1). A subgroup analysis of individuals with a past experience of depressive illness, (n = 95), revealed that a significant number screened positive for depression by the screening test, 55.2% (16/29) compared to those with no background history of depression, 33.3% (22/66) (P = 0.045). The high sensitivity and low false negative rate of the two-question screening tool will aid health professionals in identifying depression in the in-patient specialist palliative care unit. Individuals, who admit to a previous experience of depressive illness, are more likely to respond positively to the two-item questionnaire than those who report no prior history of depressive illness (P = 0.045).

Detecting asymptomatic Trichomonas vaginalis in females using the BD ProbeTec™ Trichomonas vaginalis Qx nucleic acid amplification test.

PubMed

Lord, Emily; Newnham, Tana; Dorrell, Lucy; Jesuthasan, Gerald; Clarke, Lorraine; Jeffery, Katie; Sherrard, Jackie

2017-03-01

Trichomonas vaginalis (TV) rates in women are increasing and many are asymptomatic. Nucleic acid amplification tests (NAATs) are becoming the 'gold standard' for diagnosis. We aimed to establish our asymptomatic TV rates by testing all women attending Oxfordshire's Sexual Health service, regardless of symptoms, using the BD ProbeTec™ TV Q x NAATs (BDQ x ). During BDQ x 's verification process, the sensitivity and specificity were calculated using results of 220 endocervical samples from symptomatic women, compared with culture. BDQ x was subsequently implemented and prospectively evaluated over 6 months in female attendees. Wet mount microscopy was also performed in symptomatics. Demographic and clinical characteristics of those diagnosed were analysed. From 220 samples tested by BDQ x and culture: 5 were positive on both and one solely using BDQ x , giving a sensitivity and specificity of 100% and 99.53%, respectively. In the prospective cohort, of 5775 BDQ x tests, 33 (0.57%) were positive. 11/33 (33%) patients were asymptomatic. All patients diagnosed had risk factors: age >25 years (85%), residence in a deprived area (79%) and black ethnicity (21%). Despite BDQ x being highly sensitive and specific, with our low TV prevalence universal screening may not be justified. Targeted screening using local demographic data merits further investigation.

Performance of the OraQuick HCV rapid antibody test for screening exposed patients in a hepatitis C outbreak investigation.

PubMed

Gao, Fengxiang; Talbot, Elizabeth A; Loring, Carol H; Power, Jill J; Dionne-Odom, Jodie; Alroy-Preis, Sharon; Jackson, Patricia; Bean, Christine L

2014-07-01

During a nosocomial hepatitis C outbreak, emergency public clinics employed the OraQuick HCV rapid antibody test on site, and all results were verified by a standard enzyme immunoassay (EIA). Of 1,157 persons, 1,149 (99.3%) exhibited concordant results between the two tests (16 positive, 1,133 negative). The sensitivity, specificity, positive predictive value, and negative predictive value were 94.1%, 99.5%, 72.7%, and 99.9%, respectively. OraQuick performed well as a screening test during an outbreak investigation and could be integrated into future hepatitis C virus (HCV) outbreak testing algorithms. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

Red square test for visual field screening. A sensitive and simple bedside test.

PubMed

Mandahl, A

1994-12-01

A reliable bedside test for screening of visual field defects is a valuable tool in the examination of patients with a putative disease affecting the sensory visual pathways. Conventional methods such as Donders' confrontation method, counting fingers in the visual field periphery, of two-hand confrontation are not sufficiently sensitive to detect minor but nevertheless serious visual field defects. More sensitive methods requiring only simple tools are also described. In this study, a test card with four red squares surrounding a fixation target, a black dot, with a total test area of about 11 x 12.5 degrees at a distance of 30 cm, was designed for testing experience of red colour saturation in four quadrants, red square test. The Goldmann visual field was used as reference. 125 consecutive patients with pituitary adenoma (159 eyes), craniopharyngeoma (9 eyes), meningeoma (21 eyes), vascular hemisphere lesion (40 eyes), hemisphere tumour (10 eyes) and hemisphere abscess (2 eyes) were examined. The Goldmann visual field and red square test were pathological in pituitary adenomas in 35%, in craniopharyngeomas in 44%, in meningeomas in 52% and in hemisphere tumours or abscess in 100% of the eyes. Among these, no false-normal or false-pathological tests were found. However, in vascular hemisphere disease the corresponding figures were Goldmann visual field 90% and red square test 85%. The 5% difference (4 eyes) was due to Goldmann visual field defects strictly peripheral to the central 15 degrees. These defects were easily diagnosed with two-hand confrontation and

Sensitivity of F-106B Leading-Edge-Vortex Images to Flight and Vapor-Screen Parameters

NASA Technical Reports Server (NTRS)

Lamar, John E.; Johnson, Thomas D., Jr.

1988-01-01

A flight test was undertaken at NASA Langley Research Center with vapor-screen and image-enhancement techniques to obtain qualitative and quantitative information about near-field vortex flows above the wings of fighter aircraft. In particular, the effects of Reynolds and Mach numbers on the vortex system over an angle-of-attack range were sought. The relevance of these flows stems from their present and future use at many points in the flight envelope, especially during transonic maneuvers. The aircraft used in this flight program was the F-106B because it was available and had sufficient wing sweep (60 deg) to generate a significant leading-edge vortex system. The sensitivity of the visual results to vapor screen hardware and to onset flow changes is discussed.

[Parameter sensitivity of simulating net primary productivity of Larix olgensis forest based on BIOME-BGC model].

PubMed

He, Li-hong; Wang, Hai-yan; Lei, Xiang-dong

2016-02-01

Model based on vegetation ecophysiological process contains many parameters, and reasonable parameter values will greatly improve simulation ability. Sensitivity analysis, as an important method to screen out the sensitive parameters, can comprehensively analyze how model parameters affect the simulation results. In this paper, we conducted parameter sensitivity analysis of BIOME-BGC model with a case study of simulating net primary productivity (NPP) of Larix olgensis forest in Wangqing, Jilin Province. First, with the contrastive analysis between field measurement data and the simulation results, we tested the BIOME-BGC model' s capability of simulating the NPP of L. olgensis forest. Then, Morris and EFAST sensitivity methods were used to screen the sensitive parameters that had strong influence on NPP. On this basis, we also quantitatively estimated the sensitivity of the screened parameters, and calculated the global, the first-order and the second-order sensitivity indices. The results showed that the BIOME-BGC model could well simulate the NPP of L. olgensis forest in the sample plot. The Morris sensitivity method provided a reliable parameter sensitivity analysis result under the condition of a relatively small sample size. The EFAST sensitivity method could quantitatively measure the impact of simulation result of a single parameter as well as the interaction between the parameters in BIOME-BGC model. The influential sensitive parameters for L. olgensis forest NPP were new stem carbon to new leaf carbon allocation and leaf carbon to nitrogen ratio, the effect of their interaction was significantly greater than the other parameter' teraction effect.

Economic implications of three strategies for the control of taeniasis.

PubMed

Alexander, Anu; John, K R; Jayaraman, T; Oommen, Anna; Venkata Raghava, M; Dorny, Pierre; Rajshekhar, Vedantam

2011-11-01

To evaluate the cost-effectiveness of three strategies for the control of taeniasis in a community, in terms of cost per case treated. A study was conducted in South India to determine the prevalence of taeniasis by screening stool samples from 653 randomly chosen subjects, for coproantigens. The costs incurred in the project were used to estimate the cost per case screened and treated. A one-way sensitivity analysis was carried out for varying rates of taeniasis, different screening strategies and mass therapy. Further sensitivity analysis was carried out with different manpower and test costs. The rate of taeniasis as detected by ELISA for coproantigen was 3 per 1000 (2 of 653 samples). Our study showed that mass therapy without screening for taeniasis would be the most economical strategy in terms of cost per case treated if field workers are employed exclusively for either mass therapy or screening. For each strategy, costs per case treated are higher at low prevalence of taeniasis, with a sharp rise below 15%. In places that are endemic for taeniasis and neurocysticercosis, mass therapy or screening for taeniasis should be considered. Screening by stool microscopy is not cost-effective in terms of cost per case of taeniasis treated owing to its low sensitivity. Although the cost per case of taeniasis treated is high at low prevalence of taeniasis for all options, incorporating mass therapy into existing mass drug distribution programmes might prove to be the most cost-effective control strategy. © 2011 Blackwell Publishing Ltd.

Cost-effectiveness of computed tomography colonography in colorectal cancer screening: a systematic review.

PubMed

Hanly, Paul; Skally, Mairead; Fenlon, Helen; Sharp, Linda

2012-10-01

The European Code Against Cancer recommends individuals aged ≥ 50 should participate in colorectal cancer screening. CT-colonography (CTC) is one of several screening tests available. We systematically reviewed evidence on, and identified key factors influencing, cost-effectiveness of CTC screening. PubMed, Medline, and the Cochrane library were searched for cost-effectiveness or cost-utility analyses of CTC-based screening, published in English, January 1999 to July 2010. Data was abstracted on setting, model type and horizon, screening scenario(s), comparator(s), participants, uptake, CTC performance and cost, effectiveness, ICERs, and whether extra-colonic findings and medical complications were considered. Sixteen studies were identified from the United States (n = 11), Canada (n = 2), and France, Italy, and the United Kingdom (1 each). Markov state-transition (n = 14) or microsimulation (n = 2) models were used. Eleven considered direct medical costs only; five included indirect costs. Fourteen compared CTC with no screening; fourteen compared CTC with colonoscopy-based screening; fewer compared CTC with sigmoidoscopy (8) or fecal tests (4). Outcomes assessed were life-years gained/saved (13), QALYs (2), or both (1). Three considered extra-colonic findings; seven considered complications. CTC appeared cost-effective versus no screening and, in general, flexible sigmoidoscopy and fecal occult blood testing. Results were mixed comparing CTC to colonoscopy. Parameters most influencing cost-effectiveness included: CTC costs, screening uptake, threshold for polyp referral, and extra-colonic findings. Evidence on cost-effectiveness of CTC screening is heterogeneous, due largely to between-study differences in comparators and parameter values. Future studies should: compare CTC with currently favored tests, especially fecal immunochemical tests; consider extra-colonic findings; and conduct comprehensive sensitivity analyses.

Evaluation of the HISCL Anti-Treponema pallidum Assay as a Screening Test for Syphilis

PubMed Central

An, Jingna; Chen, Qixia; Liu, Qianqian; Rao, Chenli; Li, Dongdong; Wang, Tingting

2015-01-01

The resurgence of syphilis in recent years has become a serious threat to public health worldwide, and the serological detection of specific antibodies against Treponema pallidum remains the most reliable method for laboratory diagnosis of syphilis. This study examined the performance of the recently launched HISCL anti-Treponema pallidum (anti-TP) assay as a screening test for syphilis in a high-volume laboratory. The HISCL anti-TP assay was tested in 300 preselected syphilis-positive samples, 704 fresh syphilis-negative samples, 48 preselected potentially interfering samples, and 30 “borderline” samples and was compared head to head with the commercially available Lumipulse G TP-N. In this study, the HISCL anti-TP assay was in perfect agreement with the applied testing algorithms with an overall agreement of 100%, comparable to that of Lumipulse G TP-N (99.63%). The sensitivity and specificity of the HISCL anti-TP assay were 100% (95% confidence interval [CI], 98.42% to 100%) and 100% (95% CI, 99.37% to 100%), respectively. Considering the excellent ease of use and automation, high throughput, and its favorable sensitivity and specificity, the HISCL anti-TP assay may represent a new choice for syphilis screening in high-volume laboratories. PMID:25972403

Evaluation of the HISCL Anti-Treponema pallidum Assay as a Screening Test for Syphilis.

PubMed

An, Jingna; Chen, Qixia; Liu, Qianqian; Rao, Chenli; Li, Dongdong; Wang, Tingting; Tao, Chuanmin; Wang, Lanlan

2015-07-01

The resurgence of syphilis in recent years has become a serious threat to public health worldwide, and the serological detection of specific antibodies against Treponema pallidum remains the most reliable method for laboratory diagnosis of syphilis. This study examined the performance of the recently launched HISCL anti-Treponema pallidum (anti-TP) assay as a screening test for syphilis in a high-volume laboratory. The HISCL anti-TP assay was tested in 300 preselected syphilis-positive samples, 704 fresh syphilis-negative samples, 48 preselected potentially interfering samples, and 30 "borderline" samples and was compared head to head with the commercially available Lumipulse G TP-N. In this study, the HISCL anti-TP assay was in perfect agreement with the applied testing algorithms with an overall agreement of 100%, comparable to that of Lumipulse G TP-N (99.63%). The sensitivity and specificity of the HISCL anti-TP assay were 100% (95% confidence interval [CI], 98.42% to 100%) and 100% (95% CI, 99.37% to 100%), respectively. Considering the excellent ease of use and automation, high throughput, and its favorable sensitivity and specificity, the HISCL anti-TP assay may represent a new choice for syphilis screening in high-volume laboratories. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

Ethical issues in genetic counselling with special reference to haemoglobinopathies.

PubMed

Muthuswamy, Vasantha

2011-10-01

Genetic counselling is provided in places where genetic tests are carried out. The process involves pre-test counselling as well as post-test counselling to enable the individuals to face the situation and take appropriate decisions with the right frame of mind. Major ethical principles which govern the attitudes and actions of counsellors include: respect for patient autonomy, non-maleficence, beneficence, or taking action to help benefit others and prevent harm, both physical and mental, and justice, which requires that services be distributed fairly to those in need. Other moral issues include veracity, the duty to disclose information or to be truthful, and respect for patient confidentiality. Nondirective counselling, a hallmark of this profession, is in accordance with the principle of individual autonomy. High prevalence of haemoglobinopathies with availability of good and sensitive carrier detection tests and prenatal diagnostic techniques makes these good candidates for population screening of carriers along with genetic counselling for primary prevention of the disease. Screening of the extended family members of the affected child, high risk communities and general population screening including antenatal women are the main target groups for planning a Haemoglobinopathy control programme. A critical mass of trained genetic counsellors who have understanding of the ethical issues and its appropriate handling with the required sensitivity is needed in India.

Comparison of clinical and analytical performance of the Abbott Realtime High Risk HPV test to the performance of hybrid capture 2 in population-based cervical cancer screening.

PubMed

Poljak, Mario; Ostrbenk, Anja; Seme, Katja; Ucakar, Veronika; Hillemanns, Peter; Bokal, Eda Vrtacnik; Jancar, Nina; Klavs, Irena

2011-05-01

The clinical performance of the Abbott RealTime High Risk HPV (human papillomavirus) test (RealTime) and that of the Hybrid Capture 2 HPV DNA test (hc2) were prospectively compared in the population-based cervical cancer screening setting. In women >30 years old (n = 3,129), the clinical sensitivity of RealTime for detection of cervical intraepithelial neoplasia of grade 2 (CIN2) or worse (38 cases) and its clinical specificity for lesions of less than CIN2 (3,091 controls) were 100% and 93.3%, respectively, and those of hc2 were 97.4% and 91.8%, respectively. A noninferiority score test showed that the clinical specificity (P < 0.0001) and clinical sensitivity (P = 0.011) of RealTime were noninferior to those of hc2 at the recommended thresholds of 98% and 90%. In the total study population (women 20 to 64 years old; n = 4,432; 57 cases, 4,375 controls), the clinical sensitivity and specificity of RealTime were 98.2% and 89.5%, and those of hc2 were 94.7% and 87.7%, respectively. The analytical sensitivity and analytical specificity of RealTime in detecting targeted HPV types evaluated with the largest sample collection to date (4,479 samples) were 94.8% and 99.8%, and those of hc2 were 93.4% and 97.8%, respectively. Excellent analytical agreement between the two assays was obtained (kappa value, 0.84), while the analytical accuracy of RealTime was significantly higher than that of hc2. RealTime demonstrated high intralaboratory reproducibility and interlaboratory agreement with 500 samples retested 61 to 226 days after initial testing in two different laboratories. RealTime can be considered to be a reliable and robust HPV assay clinically comparable to hc2 for the detection of CIN2+ lesions in a population-based cervical cancer screening setting.

PAX1 and SOX1 methylation as an initial screening method for cervical cancer: a meta-analysis of individual studies in Asians

PubMed Central

Cui, Zhaolei; Xiao, Zhenzhou; Hu, Minhua; Jiang, Chuanhui; Lin, Yingying; Chen, Yansong

2016-01-01

Background Epigenetic alterations of gene or DNA methylation have been highlighted as promising biomarkers for early cervical cancer screening. Herein, we evaluated the diagnostic performance of paired boxed gene 1 (PAX1) and sex determining region Y-box 1 (SOX1) methylation for cervical cancer detection. Methods Eligible studies were retrieved by searching the electronic databases. Study quality was assessed according to the Quality Assessment of Diagnostic Accuracy Studies (QUADAS) checklist. The bivariate meta-analysis model was employed to plot the summary receiver operator characteristic (SROC) curve using Stata 12.0 software. Results The pooled sensitivity of PAX1 methylation was estimated to be 0.73 [95% confidence interval (CI): 0.70–0.75] in differentiating patients with HSIL (high-grade squamous intraepithelial lesion) or CIN3+ (cervical intraepithelial neoplasia type III/worse) or cervical cancer from normal individuals, corresponding to a specificity of 0.87 (95% CI: 0.85–0.89) and area under the curve (AUC) of 0.91. The SOX1 methylation test yielded an AUC of 0.82, under which, the pooled sensitivity was 0.71 (95% CI: 0.67–0.74) and specificity was 0.64 (95% CI: 0.61–0.67). Notably, the stratified analysis suggested that combing parallel testing of PAX1 methylation and human papillomavirus (HPV) DNA (AUC, sensitivity, and specificity of 0.89, 0.75, and 0.81, respectively) achieved higher accuracy than single HPV DNA testing (AUC, sensitivity, and specificity of 0.77, 0.81, and 0.70, respectively). Conclusions PAX1 or SOX1 methylation has a prospect to be an auxiliary biomarker for cervical cancer screening, and parallel testing of PAX1 methylation and HPV DNA in cervical swabs confers an improved diagnostic accuracy than single HPV DNA testing. PMID:27826568

Assessment of methicillin resistant Staphylococcus Aureus detection methods: analytical comparative study.

PubMed

Ibrahim, Omer Mohammed Ali; Bilal, Naser Eldin; Osman, Omran Fadl; Magzoub, Magzoub Abbas

2017-01-01

The heterogeneous expression of methicillin resistance in Staphylococcus aureus (MRSA) affects the efficiency of tests available to detect it. The objective of this study was to assess four phenotypic tests used to detect MRSA. This is an analytical comparative study conducted among sudanese patients during period from May 2012 to July 2014, Staphylococcus aureus strains were isolated and identified by conventional methods, and then confirmed by PCR detection of coagulase gene. PCR detection of mecA gene was used as a gold standard to assess oxacillin resistance screen agar base (ORSAB), oxacillin disc, cefoxitin disc (at different temperatures and incubation periods) and MRSA-latex agglutination test. S.aureus ATCC 25923 was used as control. Sensitivity and specificity were calculated. MRSA- latex agglutination was the most accurate test; it showed 100% of both sensitivity and specificity, followed by cefoxitin disc with sensitivity of 98.48% and specificity of 100%. However, both of oxacillin disc and oxacillin resistance screen agar base showed less accurate results, and were affected by incubation periods. Oxacillin disc after 24 h incubation both at 30°C and 35°C showed sensitivity and specificity values of 87.88% and 96.23%, respectively. However, after 48h incubation the test at 30°C showed sensitivity and specificity values of 89.39%, and 94.34%, respectively. At 35°C (48h) it showed values of 89.39%, 92.45% respectively. Specificity of ORSAB was more than oxacillin disc at 35°C after 24h incubation 98.11% and 96.23%, respectively. MRSA- latex agglutination and cefoxitin disc diffusion tests are recommended for routine detection of MRSA.

Diagnostic utility of a one-item question to screen for depressive disorders: results from the KORA F3 study.

PubMed

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.

Diagnostic utility of a one-item question to screen for depressive disorders: results from the KORA F3 study

PubMed Central

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

The Effectiveness of Teleglaucoma versus In-Patient Examination for Glaucoma Screening: A Systematic Review and Meta-Analysis

PubMed Central

Thomas, Sera-Melisa; Jeyaraman, Maya; Hodge, William G.; Hutnik, Cindy; Costella, John; Malvankar-Mehta, Monali S.

2014-01-01

Background Glaucoma is the leading cause of irreversible visual impairment in the world affecting 60.5 million people worldwide in 2010, which is expected to increase to approximately 79.6 million by 2020. Therefore, glaucoma screening is important to detect, diagnose, and treat patients at the earlier stages to prevent disease progression and vision loss. Teleglaucoma uses stereoscopic digital imaging to take ocular images, which are transmitted electronically to an ocular specialist. The purpose is to synthesize literature to evaluate teleglaucoma, its diagnostic accuracy, healthcare system benefits, and cost-effectiveness. Methods A systematic search was conducted to help locate published and unpublished studies. Studies which evaluate teleglaucoma as a screening device for glaucoma were included. A meta-analysis was conducted to provide estimates of diagnostic accuracy, diagnostic odds ratio, and the relative percentage of glaucoma cases detected. The improvements to healthcare service quality and cost data were assessed. Results Of 11237 studies reviewed, 45 were included. Our results indicated that, teleglaucoma is more specific and less sensitive than in-person examination. The pooled estimates of sensitivity was 0.832 [95% CI 0.770, 0.881] and specificity was 0.790 [95% CI 0.668, 0.876]. The relative odds of a positive screen test in glaucoma cases are 18.7 times more likely than a negative screen test in a non-glaucoma cases. Additionally, the mean cost for every case of glaucoma detected was $1098.67 US and of teleglaucoma per patient screened was $922.77 US. Conclusion Teleglaucoma can accurately discriminate between screen test results with greater odds for positive cases. It detects more cases of glaucoma than in-person examination. Both patients and the healthcare systems benefit from early detection, reduction in wait and travel times, increased specialist referral rates, and cost savings. Teleglaucoma is an effective screening tool for glaucoma specifically for remote and under-services communities. PMID:25479593

The effectiveness of teleglaucoma versus in-patient examination for glaucoma screening: a systematic review and meta-analysis.

PubMed

Thomas, Sera-Melisa; Jeyaraman, Maya M; Jeyaraman, Maya; Hodge, William G; Hutnik, Cindy; Costella, John; Malvankar-Mehta, Monali S

2014-01-01

Glaucoma is the leading cause of irreversible visual impairment in the world affecting 60.5 million people worldwide in 2010, which is expected to increase to approximately 79.6 million by 2020. Therefore, glaucoma screening is important to detect, diagnose, and treat patients at the earlier stages to prevent disease progression and vision loss. Teleglaucoma uses stereoscopic digital imaging to take ocular images, which are transmitted electronically to an ocular specialist. The purpose is to synthesize literature to evaluate teleglaucoma, its diagnostic accuracy, healthcare system benefits, and cost-effectiveness. A systematic search was conducted to help locate published and unpublished studies. Studies which evaluate teleglaucoma as a screening device for glaucoma were included. A meta-analysis was conducted to provide estimates of diagnostic accuracy, diagnostic odds ratio, and the relative percentage of glaucoma cases detected. The improvements to healthcare service quality and cost data were assessed. Of 11237 studies reviewed, 45 were included. Our results indicated that, teleglaucoma is more specific and less sensitive than in-person examination. The pooled estimates of sensitivity was 0.832 [95% CI 0.770, 0.881] and specificity was 0.790 [95% CI 0.668, 0.876]. The relative odds of a positive screen test in glaucoma cases are 18.7 times more likely than a negative screen test in a non-glaucoma cases. Additionally, the mean cost for every case of glaucoma detected was $1098.67 US and of teleglaucoma per patient screened was $922.77 US. Teleglaucoma can accurately discriminate between screen test results with greater odds for positive cases. It detects more cases of glaucoma than in-person examination. Both patients and the healthcare systems benefit from early detection, reduction in wait and travel times, increased specialist referral rates, and cost savings. Teleglaucoma is an effective screening tool for glaucoma specifically for remote and under-services communities.

Evaluation of ID-PaGIA syphilis antibody test.

PubMed

Naaber, Paul; Makoid, Ene; Aus, Anneli; Loivukene, Krista; Poder, Airi

2009-01-01

Laboratory diagnosis of syphilis is usually accomplished by serology. There are currently a large number of different commercial treponemal tests available that vary in format, sensitivity and specificity. To evaluate the ID-PaGIA Syphilis Antibody Test as an alternative to other specific treponemal tests for primary screening or confirmation of diagnosis. Serum samples from healthy adults (n = 100) were used for detection of specificity of ID-PaGIA. To evaluate sensitivity of ID-PaGIA serum samples (n = 101) from patients with confirmed or suspected syphilis were tested for syphilis antibodies with FTA-Abs IgM, ID-PaGIA, ELISA IgM and TPHA tests. No false-positive results were found with ID-PaGIA. Sensitivity of various treponemal tests was the following: FTA-Abs IgM: 95.5%, ID-PaGIA and ELISA IgM: 94%, and TPHA 75%. The positive and negative predictive values of ID-PaGIA were 100 and 89.5%, respectively. Compared with other treponemal tests ID-PaGIA has excellent sensitivity and specificity.

Assessment of the diagnostic sensitivity and specificity of an indirect ELISA kit for the diagnosis of Brucella ovis infection in rams.

PubMed

Praud, Anne; Champion, Jean-Luc; Corde, Yannick; Drapeau, Antoine; Meyer, Laurence; Garin-Bastuji, Bruno

2012-07-09

Brucella ovis causes an infectious disease responsible for infertility and subsequent economic losses in sheep production. The standard serological test to detect B. ovis infection in rams is the complement fixation test (CFT), which has imperfect sensitivity and specificity in addition to technical drawbacks. Other available tests include the indirect enzyme-linked immunosorbent assays (I-ELISA) but no I-ELISA kit has been fully evaluated.The study aimed to compare an I-ELISA kit and the standard CFT. Our study was carried out on serum samples from 4599 rams from the South of France where the disease is enzootic. A Bayesian approach was used to estimate tests characteristics (diagnostic sensitivity, Se and diagnostic specificity, Sp). The tests were then studied together in order to optimise testing strategies to detect B. ovis. After optimising the cut-off values in order to avoid doubtful results without deteriorating the concordance between the results of the two tests, the I-ELISA appeared to be slightly more sensitive than CFT (Se I-ELISA=0.917 [0.822; 0.992], 95% Credibility Interval (CrI) compared to Se CFT=0.860 [0.740; 0.967], 95% CrI). However, CFT was slightly more specific than I-ELISA (Sp CFT=0.988 [0.947; 1.0], 95% CrI) compared to Sp I-ELISA =0.952 [0.901; 1.0], 95% CrI).The tests were then associated with two different interpretation schemes. The series association increased the specificity of screening and could be used for pre-movement testing in rams from uninfected flocks. The parallel association increased sequence sensitivity, thus appearing more suitable for eradicating the disease in infected flocks. The high sensitivity and acceptable specificity of this I-ELISA kit support its potential interest to avoid the limitations of CFT. The two tests could also be used together or combined with other diagnostic methods such as semen culture to improve the testing strategy. The choice of test sequence and interpretation criteria depends on the epidemiological context, screening objectives and the financial and practical constraints.

Evaluation of fecal culture and fecal RT-PCR to detect Mycobacterium avium ssp. paratuberculosis fecal shedding in dairy goats and dairy sheep using latent class Bayesian modeling.

PubMed

Bauman, Cathy A; Jones-Bitton, Andria; Jansen, Jocelyn; Kelton, David; Menzies, Paula

2016-09-20

The study's objective was to evaluate the ability of fecal culture (FCUL) and fecal PCR (FPCR) to identify dairy goat and dairy sheep shedding Mycobacterium avium ssp. paratuberculosis. A cross-sectional study of the small ruminant populations was performed in Ontario, Canada between October 2010 and August 2011. Twenty-nine dairy goat herds and 21 dairy sheep flocks were visited, and 20 lactating females > two years of age were randomly selected from each farm resulting in 580 goats and 397 sheep participating in the study. Feces were collected per rectum and cultured using the BD BACTEC™ MGIT™ 960 system using a standard (49 days) and an extended (240 days) incubation time, and underwent RT-PCR based on the hsp-X gene (Tetracore®). Statistical analysis was performed using a 2-test latent class Bayesian hierarchical model for each species fitted in WinBUGS. Extending the fecal culture incubation time statistically improved FCUL sensitivity from 23.1 % (95 % PI: 15.9-34.1) to 42.7 % (95 % PI: 33.0-54.5) in dairy goats and from 5.8 % (95 % PI: 2.3-12.4) to 19.0 % (95 % PI: 11.9-28.9) in dairy sheep. FPCR demonstrated statistically higher sensitivity than FCUL (49 day incubation) with a sensitivity of 31.9 % (95 % PI: 22.4-43.1) in goats and 42.6 % (95 % PI: 28.8-63.3) in sheep. Fecal culture demonstrates such low sensitivity at the standard incubation time it cannot be recommended as a screening test to detect shedding of MAP in either goats or sheep. Extending the incubation time resulted in improved sensitivity; however, it is still disappointingly low for screening purposes. Fecal PCR should be the screening test of choice in both species; however, it is important to recognize that control programs should not be based on testing alone when they demonstrate such low sensitivity.

Parental questionnaire as a screening instrument for motor function at age five.

PubMed

Nordbye-Nielsen, Kirsten; Kesmodel, Ulrik Schiøler

2014-12-01

No standardised method is used to determine motor function in children in general practice in Denmark. Our aim was to evaluate the correlation between a parental questionnaire assessing motor function at the age of five years and the clinical test Movement Assessment Battery for Children (M-ABC), and to assess whether one or more questions could be used to screen for motor problems at the age of five years. This study was based on a parental questionnaire containing ten questions. The M-ABC was used as the gold standard. n = 755 children. The Mann-Whitney rank sum test, Pearson's χ(2)-test, logistic regression analyses and sensitivity and specificity were used to assess the correlation between the questionnaire and the M-ABC test. The best screening tool was six questions in combination: sensitivity 39.8%, specificity 87.1%. Asking if a health professional ever expressed concern about the childs motor development had a sensitivity of 17.0% and a specificity of 93.9%. A parental questionnaire used as a screening instrument to identify children with motor problems has a reasonable specificity, but a low sensitivity. The six questions can be used to identify children who do not have motor function difficulties with a relatively high certainty, and it can fairly well identify children with motor function problems. This study was primarily supported by the Centers for Disease Control and Prevention (CDC), Atlanta, Georgia, USA. Additional support was obtained from The Danish Health and Medicines Authority, the Lundbeck Foundation, Ludvig & Daara Elsass Foundation, the Augustinus Foundation, and Aase & Ejnar Danielsens Foundation. The Danish National Research Foundation has established the Danish Epidemiology Science Centre that initiated and created the Danish National Birth Cohort. The cohort is furthermore a result of a major grant from this Foundation. Additional support for the Danish National Birth Cohort is obtained from the Pharmacy Foundation, the Egmont Foundation, the March of Dimes Birth Defects Foundation, the Augustinus Foundation and the Health Foundation. Approved by the Danish National Birth Cohort (DNBC) Board of Directors, the DNBC Steering Committee, the Regional Ethics Committee, the Danish Data Protection Agency and the CDC Institutional Review Board.

Performance characteristics of a brief Family History Questionnaire to screen for Lynch syndrome in women with newly diagnosed endometrial cancer.

PubMed

Eiriksson, Lua; Aronson, Melyssa; Clarke, Blaise; Mojtahedi, Golnessa; Massey, Christine; Oza, Amit M; Gallinger, Steven; Pollett, Aaron; Mackay, Helen; Bernardini, Marcus Q; Ferguson, Sarah E

2015-02-01

The brief Family History Questionnaire (bFHQ) was developed to identify endometrial cancer patients whose family histories suggest Lynch syndrome (LS). We compared the bFHQ, extended Family History Questionnaire (eFHQ) and dictated medical records (DMRs) to determine which family history screening strategy is superior in identifying LS in unselected women with newly diagnosed endometrial cancer that have undergone universal germline testing. Prospective cohort study recruited women with newly diagnosed endometrial cancer to evaluate screening strategies to identify LS. Participants completed bFHQ and eFHQ, had tumor assessed with immunohistochemistry (IHC) for mismatch repair proteins (MMR) and micro-satellite instability testing and underwent universal germline testing for LS. The sensitivity, specificity, positive and negative predictive values (PPV, NPV) were compared between the family history screening strategies as well as IHC. 118 of 182 eligible patients (65%) consented; 87 patients (74%) were evaluable with both family history and germline mutation status. Median age was 61years (range 26-91). All 7 patients with confirmed LS were correctly identified by bFHQ, compared to 5 and 4 by eFHQ and DMR, respectively. The sensitivity, specificity, PPV and NPV values of bFHQ were 100%, 76.5%, 25.9% and 100%, respectively, performing similar to IHC testing. While eFHQ was more specific than bFHQ (86.7% vs. 76.5%, P=0.007), 2 cases of LS were missed. The patient-administered bFHQ effectively identified women with confirmed LS and is a good screening tool to triage women with endometrial cancer for further genetic assessment. Copyright © 2014 Elsevier Inc. All rights reserved.

Diagnostic accuracy of high-risk HPV DNA genotyping for primary cervical cancer screening and triage of HPV-positive women, compared to cytology: preliminary results of the PIPAVIR study.

PubMed

Chatzistamatiou, Kimon; Moysiadis, Theodoros; Angelis, Eleftherios; Kaufmann, Andreas; Skenderi, Alkmini; Jansen-Duerr, Pidder; Lekka, Irini; Kilintzis, Vasilis; Angelidou, Stamatia; Katsiki, Evangelia; Hagemann, Ingke; Tsertanidou, Athena; Koch, Isabel; Boecher, Oliver; Soutschek, Erwin; Maglaveras, Nikolaos; Agorastos, Theodoros

2017-05-01

The purpose of the presented PIPAVIR (persistent infections with human papillomaviruses; http://www.pipavir.com ) subanalysis is to assess the performance of high-risk (hr) HPV-DNA genotyping as a method of primary cervical cancer screening and triage of HPV positive women to colposcopy compared to liquid-based cytology (LBC) in an urban female population. Women, aged 30-60, provided cervicovaginal samples at the Family-Planning Centre, Hippokratio Hospital of Thessaloniki, Greece, and the Department of Gynecology and Obstetrics in Mare Klinikum, Kiel, Germany. Cytology and HPV genotyping was performed using LBC and HPV Multiplex Genotyping (MPG), respectively. Women positive for cytology [atypical squamous cells of undetermined significance (ASC-US) or worse] or hrHPV were referred for colposcopy. Among 1723/1762 women included in the final analysis, hrHPV and HPV16/18 prevalence was 17.7 and 9.6%, respectively. Cytology was ASCUS or worse in 7.6%. Cervical Intraepithelial Neoplasia grade 2 or worse (CIN2+) was detected in 28 women (1.6%). Sensitivity of cytology (ASCUS or worse) and HPV DNA testing for the detection of CIN2+ was 50.0 and 100%, and specificity was 94.49 and 85.49%, respectively. The screening approach according to which only women positive for HPV16/18 and for hrHPV(non16/18) with ASCUS or worse were referred to colposcopy presented 78.57% sensitivity and 13.17% positive predictive value (PPV). HPV testing represents a more sensitive methodology for primary cervical cancer screening compared to cytology. For triage of HPV positive women to colposcopy, partial HPV genotyping offers better sensitivity than cytology, at the cost of higher number of colposcopies.

Prospective evaluation of 64 serum autoantibodies as biomarkers for early detection of colorectal cancer in a true screening setting

PubMed Central

Chen, Hongda; Werner, Simone; Butt, Julia; Zörnig, Inka; Knebel, Phillip; Michel, Angelika; Eichmüller, Stefan B.; Jäger, Dirk; Waterboer, Tim; Pawlita, Michael; Brenner, Hermann

2016-01-01

Novel blood-based screening tests are strongly desirable for early detection of colorectal cancer (CRC). We aimed to identify and evaluate autoantibodies against tumor-associated antigens as biomarkers for early detection of CRC. 380 clinically identified CRC patients and samples of participants with selected findings from a cohort of screening colonoscopy participants in 2005–2013 (N=6826) were included in this analysis. Sixty-four serum autoantibody markers were measured by multiplex bead-based serological assays. A two-step approach with selection of biomarkers in a training set, and validation of findings in a validation set, the latter exclusively including participants from the screening setting, was applied. Anti-MAGEA4 exhibited the highest sensitivity for detecting early stage CRC and advanced adenoma. Multi-marker combinations substantially increased sensitivity at the price of a moderate loss of specificity. Anti-TP53, anti-IMPDH2, anti-MDM2 and anti-MAGEA4 were consistently included in the best-performing 4-, 5-, and 6-marker combinations. This four-marker panel yielded a sensitivity of 26% (95% CI, 13–45%) for early stage CRC at a specificity of 90% (95% CI, 83–94%) in the validation set. Notably, it also detected 20% (95% CI, 13–29%) of advanced adenomas. Taken together, the identified biomarkers could contribute to the development of a useful multi-marker blood-based test for CRC early detection. PMID:26909861

Rapid detection of multidrug resistant Gram-negative bacilli by Cica-Beta-Test strips.

PubMed

Lavigne, J-P; Pfeiffer, C; Vidal, L; Sotto, A

2011-02-01

This study aimed to evaluate the sensitivity and specificity of a new system (Cica-Beta-Test, Kanto Chemical, Japan) for rapid detection of AmpC-derepressed, extended-spectrum β-lactamases (ESβL) and metallo-β-lactamases (MβL). Two hundred Multi-Drug Resistant (MDR)-Gram-negative bacilli were studied: 170 Enterobacteriaceae and 30 Gram-negative non-fermentative bacteria. One hundred and eighteen strains produced an ESβL, seven MβL and 75 derepressed cephalosporinases. One drop of substrate was dispensed onto the filter pad of the Cica-Beta-Test strip. The bacterial colonies were spread on the filter pad of strip. The reading was performed after 2 to 15 min: turning chromogenic indicated the positive test. Three tests were used: Cica-Beta I for detection of MDR bacteria; Cica-Beta MβL for detection of MβL-producing bacteria and Cica-Beta CVA, which distinguish ESβL and AmpC-derepressed producers. Results were compared with molecular assays. Cica-Beta-Test I has detected 194 MDR (sensitivity 97%), Cica-Beta-Test MβL has shown the presence of six MβL tested (sensitivity 85.7%). Five strains were non-MβL false positive (specificity 97.3%). Cica-Beta-Test CVA allowed the differentiation of ESβL-producing strains (109/115) and AmpC-derepressed strains (56/67) (sensitivity 94.8%, specificity 83.8%). Because of their epidemic nature, the MDR strains are screened and require strict hygienic measures patients. The simultaneous use of three strips can quickly determine the presence of MDR including ESβL and MβL. Rapid screening of MDR avoids transmission and limits the use of broad-spectrum antibiotics. Copyright © 2010 Elsevier Masson SAS. All rights reserved.

Criteria To Screen for Chronic Sinonasal Disease

PubMed Central

Dixon, Anne E.; Sugar, Elizabeth A.; Zinreich, S. James; Slavin, Raymond G.; Corren, Jonathan; Naclerio, Robert M.; Ishii, Masaru; Cohen, Rubin I.; Brown, Ellen D.; Wise, Robert A.; Irvin, Charles G.

2009-01-01

Background: Sinusitis and rhinitis are associated with uncontrolled asthma. There are no simple, validated tools to screen for these diseases. The objective of this study was to assess instruments to assist in the diagnosis of chronic sinonasal disease. Methods: Participants without acute sinonasal symptoms underwent an extensive evaluation. The results were submitted to an expert panel that used the Delphi method to achieve consensus. Using the consensus diagnosis of the panel, we determined the sensitivity and specificity of test procedures to diagnose chronic sinonasal disease. We determined the reproducibility of the most sensitive and specific instrument in a separate cohort. Results: Fifty-nine participants were evaluated, and the expert panel reached consensus for all (42 participants with chronic sinonasal disease, 17 participants without chronic sinonasal disease). A six-item questionnaire based on the frequency of nasal symptoms was the most sensitive tool used to diagnose sinonasal disease (minimum specificity, 0.90). Reproducibility testing in a separate cohort of 63 participants (41 chronic sinonasal disease with asthma, 22 chronic sinonasal disease without asthma) showed a concordance correlation coefficient of 0.91 (95% CI, 0.85 to 0.94) when this questionnaire was limited to five items (ie, excluding a question on smell). This five-item questionnaire had a sensitivity of 0.90 (95% CI, 0.77 to 0.97), a specificity of 0.94 (95% CI, 0.71 to 1.00), and an area under the receiver operating characteristic curve of 0.97 (95% CI, 0.93 to 1.0). Sinus CT scans and nasal endoscopy lacked sensitivity for use in the diagnosis of chronic sinonasal disease. Conclusions: We have developed a sensitive, specific, and reproducible instrument to screen for chronic sinonasal disease. Validation studies of this five-item questionnaire are needed, including in patients with asthma. PMID:19581356

Screening for colon cancer: A test for occult blood.

PubMed

Khakimov, N; Khasanova, G; Ershova, K; Gibadullina, L; Vetkina, T; Lobisheva, G; Chumakova, A

2015-01-01

The relevance of the problem of colorectal cancer (CRC) is evident because of extremely high morbidity and mortality rates, associated with this disease. CRC is mostly diagnosed only at very advanced stages. The reduction of mortality can be achieved by the popularization of screening-methods for early identification of CRC and adenomatous polyps of the colon, which are proved to be precancerous condition. Fecal occult blood test is a well-known method of screening for CRC. The advantages of this method when compared, for example, with colonoscopy are its simplicity and cost-effectiveness.Two techniques are usually used for detection of occult blood in the stool: Hemoccult (Guaiac) test and immunochemical test for hemoglobin. There is no consensus among researchers regarding the validity of these tests for the diagnosis of colorectal cancer. For example, J.S. Mandel (1996) notes 60% sensitivity of Guaiac-test for the detection of the early forms of colorectal cancer, while O.I. Kit (2014) suggets that it is not higher than 30%. There are also various opinions about specificity of these two tests. To review the literature on the validity of the fecal occult blood tests for the diagnosis of CRC. We looked for articles (electronic versions) available for free in the full-text versions, published from June 1, 1990 to December 31, 2014 in Russian or English. The following databases were used for search: E-LIBRARY; Cochrane; MEDLINE; EMBASE; Google search. Only original research papers were analyzed. Literature reviews or systematic reviews were not taken for analyses. 1) use of Guaiac and/or immunochemical fecal occult blood test as screening-tests for the detection of colorectal cancer and/or colon polyps (1 cm or more in diameter) in people older than 45 years; 2) comparing of results with the results of colonoscopy (colonoscopy is counted by majority of the authors as a "gold standard" for the diagnosis of CRC and adenomatous polyps). Initial keyword search returned 803 000 results, of which 449 sources were selected. After reading the abstracts, 29 articles that met inclusion criteria were kept. 10 other articles were excluded after that because they did not contain enough data for extraction or did not contain a control group. At the final step 19 articles were used for meta-analysis.Forest plot and Rock curve, which were developed with inclusion of the data from all studies, showed heterogeneity of the data. Additional analyzes were performed in subgroups with different diagnoses and various tests.The sensitivity of the Guaiac test for the diagnosis of colorectal cancer varied from 0.13 to 1.00, and specificity - from 0.69 to 0.99. The sensitivity of the immunochemical test for the diagnosis of CRC ranged from 0.42 to 0.94 with specificity ranging from 0.40 to 1.00.The sensitivity of the Guaiac test for the diagnosis of the colon polyps was between 0.05 and 0.69, and its specificity - from 0.67 to 0.98. The sensitivity of the immunochemical test for the diagnosis of polyps was from 0.24 to 0.75, and its specificity - from 0.40 to 0.97.Bivariate analysis of the validity of Guaiac test and immunochemical method for the diagnosis of colorectal cancer showed better results for the immunochemical test compared to Guaiac test. The tests showed very similar results when used for the diagnosis of polyposis. Bivariate analysis, comparing the validity of tests for the diagnosis of colorectal cancer versus polyposis demonstrated better results for CRC.Multivariate analysis of the validity of the Guaiac and immunochemical tests for the diagnosis of colorectal cancer and polyps also showed better results for detection of colorectal cancer compared with the polyps for both tests. At the same time the highest validity for the diagnosis of CRC was demonstrated for immunochemical analysis. 1. The sensitivity of the Guaiac test for occult blood in stool is lower than its specificity.2. Broad dispersion of the validity characteristics of the fecal occult blood tests was observed.3. The validity of tests for occult blood was higher when they were used for detection of colorectal cancer than of colon polyposis.4. The highest validity rate has been demonstrated for the immunochemical test when it was used for colon cancer screening.

Neuropad for the detection of cardiovascular autonomic neuropathy in patients with type 2 diabetes.

PubMed

Mendivil, Carlos O; Kattah, William; Orduz, Arturo; Tique, Claudia; Cárdenas, José L; Patiño, Jorge E

2016-01-01

Cardiovascular autonomic neuropathy (CAN) is a prevalent and neglected chronic complication of diabetes, with a large impact on morbidity and mortality. Part of the reason why it is not detected and treated opportunely is because of the complexity of the tests required for its diagnosis. We evaluated the Neuropad®, a test based on sudomotor function, as a screening tool for CAN in adult patients with type 2 diabetes in Bogotá, Colombia. This was a cross-sectional evaluation of Neuropad® for the detection of CAN. Patients were 20-75years of age and did not suffer from any other type of neuropathy. CAN was diagnosed using the Ewing battery of tests for R-R variability during deep breathing, Valsalva and lying-to-standing maneuvers. Additionally, distal symmetric polyneuropathy (DSP) was diagnosed using a sign-based scale (Michigan Neuropathy Disability Score - NDS) and a symptom-based score (Total Symptom Score - TSS). The primary outcome was the sensitivity and specificity of the Neuropad® for the diagnosis of CAN, and secondary outcomes were the sensitivity and specificity of Neuropad® for DSP. We studied 154 patients (74 men and 80 women). Prevalence of CAN was extremely high (68.0% of study participants), but also DSP was prevalent, particularly according to the signs-based definition (45%). The sensitivity of the Neuropad® for any degree of CAN was 70.1%, being slightly higher for the deep breathing and Valsalva tests than for lying-to-standing. The specificity of the Neuropad® for any type of CAN was only 37.0%, as expected for a screening exam. The negative predictive value was higher for the deep breathing and Valsalva tests (69.4 and 81.6%, respectively). Neuropad showed also a good sensitivity and negative predictive value for DSP. The sensitivity and specificity of Neuropad were better among men, and among patients with diabetes duration above the group median. The Neuropad is a simple and inexpensive device that demonstrated an adequate performance as a screening tool for cardiovascular autonomic neuropathy in Latin American patients with DM2. Copyright © 2016 Elsevier Inc. All rights reserved.

[Effectiveness of FTA Elute® indicating cartridge in combination with hybrid capture 2 for cervical cancer screening].

PubMed

Chen, Feng; Zhang, Xi; Wang, Shaoming; Hu, Shangying; Chen, Wen; Zhao, Fanghui; He, Wei; Zhang, Yuqing; Qiao, Youlin

2015-02-01

To evaluate the effectiveness of FTA Elute® Cartridge (GE healthcare, Kent, UK) in combination with hybrid capture 2 (HC2) testing for cervical cancer screening. From May to June 2012, 412 women aged 25 to 65 years in Jiangxi Tonggu were enrolled in the study. We used pathological outcome as the gold standard, and the accuracy of the FTA card in combination with HC2 testing was investigated from both physician- and self-sampling, respectively. Physician sampling using the FTA card in combination with HC2 testing showed a comparable sensitivity (12/13) with the liquid based medium, but a higher specificity 69.5% (266/383) vs (77.8%, 298/383) (P < 0.001).When self sampling method was used, the sensitivity and specificity of using the FTA card in combination with HC2 testing with liquid based medium was 10/13 vs 8/13(P = 0.625) and (62.3%, 238/382) vs (75.7%, 289/382) (P < 0.001). The agreement of detection results for HC2 between FTA and liquid-based sampling medium was 86.1% (340/395) and 79.5% (314/395). For physician-collected samples used for HC2 testing to detect CIN2+, the accuracy of the FTA card was superior to that of the liquid-based medium (area under the receiver operating characteristic curve (AUC) = 0.898, 95%CI:0.838-0.958). FTA Elute® cartridge in combination with HC2 testing is a promising method of specimen transport for cervical cancer screening programs with a good precision.With further optimization, it could become an effective method for cervical cancer screening in various economic levels of areas.

Evaluation of a New and Rapid Serologic Test for Detecting Brucellosis: Brucella Coombs Gel Test.

PubMed

Hanci, Hayrunisa; Igan, Hakan; Uyanik, Muhammet Hamidullah

2017-01-01

Many serological tests have been used for the diagnosis of human brucellosis. A new serological method is identified as Brucella Coombs gel test based on the principle of centrifugation gel system similar to the gel system used in blood group determination. In this system, if Brucella antibodies were present in the serum, antigen and antibody would remain as a pink complex on the gel. Otherwise, the pink Brucella antigens would precipitate at the bottom of the gel card system. In this study, we aimed to compare the Brucella Coombs gel test, a new, rapid screen and titration method for detection of non-agglutinating IgG with the Brucella Coombs test. For this study, a total of 88 serum samples were obtained from 45 healthy persons and 43 individuals who had clinical signs and symptoms of brucellosis. For each specimen, Rose Bengal test, standard agglutination test, Coombs test and Brucella Coombs gel test were carried out. Sensitivity and specificity of Brucella Coombs gel test were found as 100.0 and 82.2%, respectively. Brucella Coombs gel test can be used as a screening test with high sensitivity. By the help of pink Brucella antigen precipitation, the tests' evaluation is simple and objective. In addition, determination of Brucella antibody by rapid titration offers another important advantage.

Systematic Review of the Performance of Noninvasive Tests in Diagnosing Bladder Outlet Obstruction in Men with Lower Urinary Tract Symptoms.

PubMed

Malde, Sachin; Nambiar, Arjun K; Umbach, Roland; Lam, Thomas B; Bach, Thorsten; Bachmann, Alexander; Drake, Marcus J; Gacci, Mauro; Gratzke, Christian; Madersbacher, Stephan; Mamoulakis, Charalampos; Tikkinen, Kari A O; Gravas, Stavros

2017-03-01

Several noninvasive tests have been developed for diagnosing bladder outlet obstruction (BOO) in men to avoid the burden and morbidity associated with invasive urodynamics. The diagnostic accuracy of these tests, however, remains uncertain. To systematically review available evidence regarding the diagnostic accuracy of noninvasive tests in diagnosing BOO in men with lower urinary tract symptoms (LUTS) using a pressure-flow study as the reference standard. The EMBASE, MEDLINE, Cochrane Database of Systematic Reviews, Cochrane Central, Google Scholar, and WHO International Clinical Trials Registry Platform Search Portal databases were searched up to May 18, 2016. All studies reporting diagnostic accuracy for noninvasive tests for BOO or detrusor underactivity in men with LUTS compared to pressure-flow studies were included. Two reviewers independently screened all articles, searched the reference lists of retrieved articles, and performed the data extraction. The quality of evidence and risk of bias were assessed using the QUADAS-2 tool. The search yielded 2774 potentially relevant reports. After screening titles and abstracts, 53 reports were retrieved for full-text screening, of which 42 (recruiting a total of 4444 patients) were eligible. Overall, the results were predominantly based on findings from nonrandomised experimental studies and, within the limits of such study designs, the quality of evidence was typically moderate across the literature. Differences in noninvasive test threshold values and variations in the urodynamic definition of BOO between studies limited the comparability of the data. Detrusor wall thickness (median sensitivity 82%, specificity 92%), near-infrared spectroscopy (median sensitivity 85%, specificity 87%), and the penile cuff test (median sensitivity 88%, specificity 75%) were all found to have high sensitivity and specificity in diagnosing BOO. Uroflowmetry with a maximum flow rate of <10ml/s was reported to have lower median sensitivity and specificity of 68% and 70%, respectively. Intravesical prostatic protrusion of >10mm was reported to have similar diagnostic accuracy, with median sensitivity of 68% and specificity of 75%. According to the literature, a number of noninvasive tests have high sensitivity and specificity in diagnosing BOO in men. However, although the majority of studies have a low overall risk of bias, the available evidence is limited by heterogeneity. While several tests have shown promising results regarding noninvasive assessment of BOO, invasive urodynamics remain the gold standard. Urodynamics is an accurate but potentially uncomfortable test for patients in diagnosing bladder problems such as obstruction. We performed a thorough and comprehensive review of the literature to determine if there were less uncomfortable but equally effective alternatives to urodynamics for diagnosing bladder problems. We found that some simple tests appear to be promising, although they are not as accurate. Further research is needed before these tests are routinely used in place of urodynamics. Copyright © 2016 European Association of Urology. Published by Elsevier B.V. All rights reserved.

Screening for alcohol use disorders and at-risk drinking in the general population: psychometric performance of three questionnaires.

PubMed

Rumpf, Hans-Jürgen; Hapke, Ulfert; Meyer, Christian; John, Ulrich

2002-01-01

Most screening questionnaires are developed in clinical settings and there are few data on their performance in the general population. This study provides data on the area under the receiver-operating characteristic (ROC) curve, sensitivity, specificity, and internal consistency of the Alcohol Use Disorders Identification Test (AUDIT), the consumption questions of the AUDIT (AUDIT-C) and the Lübeck Alcohol Dependence and Abuse Screening Test (LAST) among current drinkers (n = 3551) of a general population sample in northern Germany. Alcohol dependence and misuse according to DSM-IV and at-risk drinking served as gold standards to assess sensitivity and specificity and were assessed with the Munich-Composite Diagnostic Interview (M-CIDI). AUDIT and LAST showed insufficient sensitivity for at-risk drinking and alcohol misuse using standard cut-off scores, but satisfactory detection rates for alcohol dependence. The AUDIT-C showed low specificity in all criterion groups with standard cut-off. Adjusted cut-points are recommended. Among a subsample of individuals with previous general hospital admission in the last year, all questionnaires showed higher internal consistency suggesting lower reliability in non-clinical samples. In logistic regression analyses, having had a hospital admission increased the sensitivity in detecting any criterion group of the LAST, and the number of recent general practice visits increased the sensitivity of the AUDIT in detecting alcohol misuse. Women showed lower scores and larger areas under the ROC curves. It is concluded that setting specific instruments (e.g. primary care or general population) or adjusted cut-offs should be used.

Comparison of the MoCA and BEARNI tests for detection of cognitive impairment in in-patients with alcohol use disorders.

PubMed

Pelletier, Stéphanie; Alarcon, Régis; Ewert, Valérie; Forest, Margot; Nalpas, Bertrand; Perney, Pascal

2018-06-01

Screening of cognitive impairment is a major challenge in alcoholics seeking treatment, since cognitive dysfunction may impair the overall efficacy of rehabilitation programs and consequently increase relapse rate. We compared the performance of two screening tools: the MoCA (Montreal Cognitive Assessment), which is widely used in patients with neurological diseases and already used in patients with alcohol use disorder (AUD), and the BEARNI (Brief Evaluation of Alcohol-Related Neuropsychological Impairments), a recent test specifically developed for the alcoholic population. We compared the sensitivity and specificity of the MoCA and the BEARNI in a sample of AUD patients with and without cognitive impairment assessed by a battery of neuropsychological tests. Ninety patients were included. There were 67 men and 23 women aged 48.9 ± 9.6 years. According to the neuropsychological tests, 51.1% of patients had no cognitive impairment, while it was mild or moderate to severe in 31.1 and 17.8%, respectively. The BEARNI sensitivity was extremely high (1.0), since all patients with cognitive impairment were identified, but its specificity was very low (0.04). The MoCA had a lower sensitivity (0.79) than the BEARNI, but its specificity was significantly better (0.65). A detailed analysis of the BEARNI scores showed a discrepancy between the qualitative and quantitative interpretation of the test which could, at least in part, explain its low specificity. Both the MoCA and the BEARNI are screening tools which identified alcoholic patients with cognitive impairment. However, in routine use, the MoCA appeared to be more appropriate given the low specificity of the BEARNI. Copyright © 2018 Elsevier B.V. All rights reserved.

Discovery of Novel Cell Wall-Active Compounds Using PywaC, a Sensitive Reporter of Cell Wall Stress, in the Model Gram-Positive Bacterium Bacillus subtilis

PubMed Central

Czarny, T. L.; Perri, A. L.; French, S.

2014-01-01

The emergence of antibiotic resistance in recent years has radically reduced the clinical efficacy of many antibacterial treatments and now poses a significant threat to public health. One of the earliest studied well-validated targets for antimicrobial discovery is the bacterial cell wall. The essential nature of this pathway, its conservation among bacterial pathogens, and its absence in human biology have made cell wall synthesis an attractive pathway for new antibiotic drug discovery. Herein, we describe a highly sensitive screening methodology for identifying chemical agents that perturb cell wall synthesis, using the model of the Gram-positive bacterium Bacillus subtilis. We report on a cell-based pilot screen of 26,000 small molecules to look for cell wall-active chemicals in real time using an autonomous luminescence gene cluster driven by the promoter of ywaC, which encodes a guanosine tetra(penta)phosphate synthetase that is expressed under cell wall stress. The promoter-reporter system was generally much more sensitive than growth inhibition testing and responded almost exclusively to cell wall-active antibiotics. Follow-up testing of the compounds from the pilot screen with secondary assays to verify the mechanism of action led to the discovery of 9 novel cell wall-active compounds. PMID:24687489

Health benefits and cost-effectiveness of a hybrid screening strategy for colorectal cancer.

PubMed

Dinh, Tuan; Ladabaum, Uri; Alperin, Peter; Caldwell, Cindy; Smith, Robert; Levin, Theodore R

2013-09-01

Colorectal cancer (CRC) screening guidelines recommend screening schedules for each single type of test except for concurrent sigmoidoscopy and fecal occult blood test (FOBT). We investigated the cost-effectiveness of a hybrid screening strategy that was based on a fecal immunological test (FIT) and colonoscopy. We conducted a cost-effectiveness analysis by using the Archimedes Model to evaluate the effects of different CRC screening strategies on health outcomes and costs related to CRC in a population that represents members of Kaiser Permanente Northern California. The Archimedes Model is a large-scale simulation of human physiology, diseases, interventions, and health care systems. The CRC submodel in the Archimedes Model was derived from public databases, published epidemiologic studies, and clinical trials. A hybrid screening strategy led to substantial reductions in CRC incidence and mortality, gains in quality-adjusted life years (QALYs), and reductions in costs, comparable with those of the best single-test strategies. Screening by annual FIT of patients 50-65 years old and then a single colonoscopy when they were 66 years old (FIT/COLOx1) reduced CRC incidence by 72% and gained 110 QALYs for every 1000 people during a period of 30 years, compared with no screening. Compared with annual FIT, FIT/COLOx1 gained 1400 QALYs/100,000 persons at an incremental cost of $9700/QALY gained and required 55% fewer FITs. Compared with FIT/COLOx1, colonoscopy at 10-year intervals gained 500 QALYs/100,000 at an incremental cost of $35,100/QALY gained but required 37% more colonoscopies. Over the ranges of parameters examined, the cost-effectiveness of hybrid screening strategies was slightly more sensitive to the adherence rate with colonoscopy than the adherence rate with yearly FIT. Uncertainties associated with estimates of FIT performance within a program setting and sensitivities for flat and right-sided lesions are expected to have significant impacts on the cost-effectiveness results. In our simulation model, a strategy of annual or biennial FIT, beginning when patients are 50 years old, with a single colonoscopy when they are 66 years old, delivers clinical and economic outcomes similar to those of CRC screening by single-modality strategies, with a favorable impact on resources demand. Copyright © 2013 AGA Institute. Published by Elsevier Inc. All rights reserved.

Newborn screening for cystic fibrosis in Wisconsin: comparison of biochemical and molecular methods.

PubMed

Gregg, R G; Simantel, A; Farrell, P M; Koscik, R; Kosorok, M R; Laxova, A; Laessig, R; Hoffman, G; Hassemer, D; Mischler, E H; Splaingard, M

1997-06-01

To evaluate neonatal screening for cystic fibrosis (CF), including study of the screening procedures and characteristics of false-positive infants, over the past 10 years in Wisconsin. An important objective evolving from the original design has been to compare use of a single-tier immunoreactive trypsinogen (IRT) screening method with that of a two-tier method using IRT and analyses of samples for the most common cystic fibrosis transmembrane regulator (CFTR) (DeltaF508) mutation. We also examined the benefit of including up to 10 additional CFTR mutations in the screening protocol. From 1985 to 1994, using either the IRT or IRT/DNA protocol, 220 862 and 104 308 neonates, respectively, were screened for CF. For the IRT protocol, neonates with an IRT >/=180 ng/mL were considered positive, and the standard sweat chloride test was administered to determine CF status. For the IRT/DNA protocol, samples from the original dried-blood specimen on the Guthrie card of neonates with an IRT >/=110 ng/mL were tested for the presence of the DeltaF508 CFTR allele, and if the DNA test revealed one or two DeltaF508 alleles, a sweat test was obtained. Both screening procedures had very high specificity. The sensitivity tended to be higher with the IRT/DNA protocol, but the differences were not statistically significant. The positive predictive value of the IRT/DNA screening protocol was 15.2% compared with 6.4% if the same samples had been screened by the IRT method. Assessment of the false-positive IRT/DNA population revealed that the two-tier method eliminates the disproportionate number of infants with low Apgar scores and also the high prevalence of African-Americans identified previously in our study of newborns with high IRT levels. We found that 55% of DNA-positive CF infants were homozygous for DeltaF508 and 40% had one DeltaF508 allele. Adding analyses for 10 more CFTR mutations has only a small effect on the sensitivity but is likely to add significantly to the cost of screening. Advantages of the IRT/DNA protocol over IRT analysis include improved positive predictive value, reduction of false-positive infants, and more rapid diagnosis with elimination of recall specimens.

Comparison of diagnostic techniques for the detection of Cryptosporidium oocysts in animal samples

PubMed Central

Mirhashemi, Marzieh Ezzaty; Zintl, Annetta; Grant, Tim; Lucy, Frances E.; Mulcahy, Grace; De Waal, Theo

2015-01-01

While a large number of laboratory methods for the detection of Cryptosporidium oocysts in faecal samples are now available, their efficacy for identifying asymptomatic cases of cryptosporidiosis is poorly understood. This study was carried out to determine a reliable screening test for epidemiological studies in livestock. In addition, three molecular tests were compared to identify Cryptosporidium species responsible for the infection in cattle, sheep and horses. A variety of diagnostic tests including microscopic (Kinyoun's staining), immunological (Direct Fluorescence Antibody tests or DFAT), enzyme-linked immunosorbent assay (ELISA), and molecular methods (nested PCR) were compared to assess their ability to detect Cryptosporidium in cattle, horse and sheep faecal samples. The results indicate that the sensitivity and specificity of each test is highly dependent on the input samples; while Kinyoun's and DFAT proved to be reliable screening tools for cattle samples, DFAT and PCR analysis (targeted at the 18S rRNA gene fragment) were more sensitive for screening sheep and horse samples. Finally different PCR primer sets targeted at the same region resulted in the preferential amplification of certain Cryptosporidium species when multiple species were present in the sample. Therefore, for identification of Cryptosporidium spp. in the event of asymptomatic cryptosporidiosis, the combination of different 18S rRNA nested PCR primer sets is recommended for further epidemiological applications and also tracking the sources of infection. PMID:25662435

International variation in the prevalence of preclinical colorectal cancer: Implications for predictive values of noninvasive screening tests and potential target populations for screening

PubMed Central

Stock, Christian; Brenner, Hermann

2017-01-01

Screening for colorectal cancer (CRC) is implemented in an increasing number of countries. We aimed to assess international variation in the prevalence of preclinical CRC and the resulting variation in positive and negative predictive values (PPVs, NPVs) of existing and potential CRC screening tests in various countries. Using age‐ and sex‐specific CRC incidence data and transition rates from preclinical to clinical CRC we estimated overall and age‐ and sex‐specific prevalence of preclinical CRC in the target population aged 50–74 years in different parts of the world. These prevalence estimates were used to derive PPVs and NPVs for existing and potential noninvasive screening tests with varying levels of sensitivity and specificity. Within all regions and countries, prevalence strongly increases with age and is higher in men than in women. In addition, major variation was seen between regions and countries, with overall prevalence varying between 1 and 0.1%. As a result, PPVs are expected to strongly vary between ∼10% for men in high incidence countries, such as Australia and Germany, and 1% for women in low incidence countries, whereas NPVs are expected to be consistently well above 99%. Variation in CRC prevalence profoundly affects expected PPVs of screening tests, and PPVs should be carefully considered when decisions on screening tests and strategies are made for specific populations and health care systems. Here, we provide estimates of preclinical CRC and expected PPVs and NPVs of noninvasive screening tests, which may enhance the empirical basis for planning of population‐based CRC screening strategies. PMID:28670788

The Abbreviated Mental Test 4 for cognitive screening of older adults presenting to the Emergency Department.

PubMed

Dyer, Adam H; Briggs, Robert; Nabeel, Shamis; O'Neill, Desmond; Kennelly, Sean P

2017-12-01

A commonly cited reason for the infrequent detection of cognitive impairment in the Emergency Department (ED) is the lack of an appropriate screening tool. The Abbreviated Mental Test 4 (AMT4) is a brief instrument recommended for cognitive screening of older adults in the ED. However, its exact utility in the detection of altered mental status in the ED is yet to be fully determined. The present study evaluated the ability of the AMT4 to identify impaired mental status in the ED, defined as positive scores on either the Confusion Assessment Method-ICU for delirium, the standardized Mini Mental State Examination as a general cognitive screener or the Eight-item Interview to Differentiate Aging and Dementia for dementia. Of 196 adults at least 70 years of age (mean: 78.5±5.9), the AMT4 had a sensitivity of 0.53 (0.42-0.63) and a specificity of 0.96 (0.89-0.99) for impaired mental status in the ED. The AMT4 was positive in almost all patients (92%; 24/26) screening positive for delirium, but less than half (47.8%; 22/46) of those screening positive for probable dementia, and less than a quarter (22.2%; 6/27) of those screening positive for probable cognitive impairment. The present study found that the limited sensitivity of the AMT4 in identifying the majority of cognitively impaired persons restricts its use in isolation as a general cognitive screener in the ED.

Rapid screening for the detection of HLA-B57 and HLA-B58 in prevention of drug hypersensitivity.

PubMed

Kostenko, L; Kjer-Nielsen, L; Nicholson, I; Hudson, F; Lucas, A; Foley, B; Chen, K; Lynch, K; Nguyen, J; Wu, A H B; Tait, B D; Holdsworth, R; Mallal, S; Rossjohn, J; Bharadwaj, M; McCluskey, J

2011-07-01

HLA-B57 and HLA-B58 are major histocompatibility class (MHC)-I allotypes that are potentially predictive of important clinical immune phenotypes. HLA-B*5701 is strongly associated with hypersensitivity to the HIV drug abacavir, liver toxicity from the antibiotic flucloxacillin and is a marker for slow progression of HIV AIDS. HLA-B*5801 is associated with hypersensitivity to allopurinol used to treat hyperuricaemia and recurrent gout. Here we describe a monoclonal antibody (mAb) specific for HLA-B57 and HLA-B58 that provides an inexpensive and sensitive screen for these MHC-I allotypes. The usefulness of HLA-B57 screening for prediction of abacavir hypersensitivity was shown in three independent laboratories, including confirmation of the mAb sensitivity and specificity in a cohort of patients enrolled in the PREDICT-1 trial. Our data show that patients who test negative by mAb screening comprise 90%-95% of all individuals in most human populations and require no further human leukocyte antigen (HLA) typing. Patients who test positive by mAb screening should proceed to high-resolution typing to ascertain the presence of HLA-B*5701 or HLA-B*5801. Hence, mAb screening provides a low-cost alternative to high-resolution typing of all patients and lends itself to point-of-care diagnostics and rapid ascertainment of low-risk patients who can begin immediate therapy with abacavir, flucloxacillin or allopurinol. © 2011 John Wiley & Sons A/S.

Computationally inexpensive identification of noninformative model parameters by sequential screening

NASA Astrophysics Data System (ADS)

Cuntz, Matthias; Mai, Juliane; Zink, Matthias; Thober, Stephan; Kumar, Rohini; Schäfer, David; Schrön, Martin; Craven, John; Rakovec, Oldrich; Spieler, Diana; Prykhodko, Vladyslav; Dalmasso, Giovanni; Musuuza, Jude; Langenberg, Ben; Attinger, Sabine; Samaniego, Luis

2015-08-01

Environmental models tend to require increasing computational time and resources as physical process descriptions are improved or new descriptions are incorporated. Many-query applications such as sensitivity analysis or model calibration usually require a large number of model evaluations leading to high computational demand. This often limits the feasibility of rigorous analyses. Here we present a fully automated sequential screening method that selects only informative parameters for a given model output. The method requires a number of model evaluations that is approximately 10 times the number of model parameters. It was tested using the mesoscale hydrologic model mHM in three hydrologically unique European river catchments. It identified around 20 informative parameters out of 52, with different informative parameters in each catchment. The screening method was evaluated with subsequent analyses using all 52 as well as only the informative parameters. Subsequent Sobol's global sensitivity analysis led to almost identical results yet required 40% fewer model evaluations after screening. mHM was calibrated with all and with only informative parameters in the three catchments. Model performances for daily discharge were equally high in both cases with Nash-Sutcliffe efficiencies above 0.82. Calibration using only the informative parameters needed just one third of the number of model evaluations. The universality of the sequential screening method was demonstrated using several general test functions from the literature. We therefore recommend the use of the computationally inexpensive sequential screening method prior to rigorous analyses on complex environmental models.

Computationally inexpensive identification of noninformative model parameters by sequential screening

NASA Astrophysics Data System (ADS)

Mai, Juliane; Cuntz, Matthias; Zink, Matthias; Thober, Stephan; Kumar, Rohini; Schäfer, David; Schrön, Martin; Craven, John; Rakovec, Oldrich; Spieler, Diana; Prykhodko, Vladyslav; Dalmasso, Giovanni; Musuuza, Jude; Langenberg, Ben; Attinger, Sabine; Samaniego, Luis

2016-04-01

Environmental models tend to require increasing computational time and resources as physical process descriptions are improved or new descriptions are incorporated. Many-query applications such as sensitivity analysis or model calibration usually require a large number of model evaluations leading to high computational demand. This often limits the feasibility of rigorous analyses. Here we present a fully automated sequential screening method that selects only informative parameters for a given model output. The method requires a number of model evaluations that is approximately 10 times the number of model parameters. It was tested using the mesoscale hydrologic model mHM in three hydrologically unique European river catchments. It identified around 20 informative parameters out of 52, with different informative parameters in each catchment. The screening method was evaluated with subsequent analyses using all 52 as well as only the informative parameters. Subsequent Sobol's global sensitivity analysis led to almost identical results yet required 40% fewer model evaluations after screening. mHM was calibrated with all and with only informative parameters in the three catchments. Model performances for daily discharge were equally high in both cases with Nash-Sutcliffe efficiencies above 0.82. Calibration using only the informative parameters needed just one third of the number of model evaluations. The universality of the sequential screening method was demonstrated using several general test functions from the literature. We therefore recommend the use of the computationally inexpensive sequential screening method prior to rigorous analyses on complex environmental models.

Performance of six diagnostic tests to screen for Chagas disease in blood banks andprevalence of Trypanosoma cruzi infection among donors with inconclusive serologyscreening based on the analysis of epidemiological variables.

PubMed

Pereira, Gilberto de Araujo; Louzada-Neto, Francisco; Barbosa, Valdirene de Fátima; Ferreira-Silva, Márcia Maria; de Moraes-Souza, Helio

2012-01-01

The frequent occurrence of inconclusive serology in blood banks and the absence of a gold standard test for Chagas'disease led us to examine the efficacy of the blood culture test and five commercial tests (ELISA, IIF, HAI, c-ELISA, rec-ELISA) used in screening blood donors for Chagas disease, as well as to investigate the prevalence of Trypanosoma cruzi infection among donors with inconclusive serology screening in respect to some epidemiological variables. To obtain estimates of interest we considered a Bayesian latent class model with inclusion of covariates from the logit link. A better performance was observed with some categories of epidemiological variables. In addition, all pairs of tests (excluding the blood culture test) presented as good alternatives for both screening (sensitivity > 99.96% in parallel testing) and for confirmation (specificity > 99.93% in serial testing) of Chagas disease. The prevalence of 13.30% observed in the stratum of donors with inconclusive serology, means that probably most of these are non-reactive serology. In addition, depending on the level of specific epidemiological variables, the absence of infection can be predicted with a probability of 100% in this group from the pairs of tests using parallel testing. The epidemiological variables can lead to improved test results and thus assist in the clarification of inconclusive serology screening results. Moreover, all combinations of pairs using the five commercial tests are good alternatives to confirm results.

The Clinical and Economic Benefits of Co-Testing Versus Primary HPV Testing for Cervical Cancer Screening: A Modeling Analysis.

PubMed

Felix, Juan C; Lacey, Michael J; Miller, Jeffrey D; Lenhart, Gregory M; Spitzer, Mark; Kulkarni, Rucha

2016-06-01

Consensus United States cervical cancer screening guidelines recommend use of combination Pap plus human papillomavirus (HPV) testing for women aged 30 to 65 years. An HPV test was approved by the Food and Drug Administration in 2014 for primary cervical cancer screening in women age 25 years and older. Here, we present the results of clinical-economic comparisons of Pap plus HPV mRNA testing including genotyping for HPV 16/18 (co-testing) versus DNA-based primary HPV testing with HPV 16/18 genotyping and reflex cytology (HPV primary) for cervical cancer screening. A health state transition (Markov) model with 1-year cycling was developed using epidemiologic, clinical, and economic data from healthcare databases and published literature. A hypothetical cohort of one million women receiving triennial cervical cancer screening was simulated from ages 30 to 70 years. Screening strategies compared HPV primary to co-testing. Outcomes included total and incremental differences in costs, invasive cervical cancer (ICC) cases, ICC deaths, number of colposcopies, and quality-adjusted life years for cost-effectiveness calculations. Comprehensive sensitivity analyses were performed. In a simulation cohort of one million 30-year-old women modeled up to age 70 years, the model predicted that screening with HPV primary testing instead of co-testing could lead to as many as 2,141 more ICC cases and 2,041 more ICC deaths. In the simulation, co-testing demonstrated a greater number of lifetime quality-adjusted life years (22,334) and yielded $39.0 million in savings compared with HPV primary, thereby conferring greater effectiveness at lower cost. Model results demonstrate that co-testing has the potential to provide improved clinical and economic outcomes when compared with HPV primary. While actual cost and outcome data are evaluated, these findings are relevant to U.S. healthcare payers and women's health policy advocates seeking cost-effective cervical cancer screening technologies.

Screening for sexually transmitted infection pathogens in semen samples

PubMed Central

Peeling, RW; Embree, J

2005-01-01

The transmission of sexually transmitted infection (STI) pathogens from an infected donor to the recipient of a semen donation in assisted conception may result not only in acute infection but also in long-term reproductive complications or adverse outcomes of pregnancy, including infection of the offspring. Screening for bacterial STI pathogens, Chlamydia trachomatis and Neisseria gonorrhoeae is strongly recommended because these pathogens can cause serious reproductive complications in the recipients of semen donations and infection in their offspring. Screening for these pathogens should be performed using the most sensitive methods, such as nucleic acid amplified tests. False-negative results due to inhibitory substances in the semen sample should be monitored using amplification controls. Where specimen transport is not a problem and culture facilities are available, N gonorrhoeae can also be detected by culture. Laboratories performing screening should subscribe to proficiency programs and have strict quality controls. Although Trichomonas vaginalis, group B streptococcus and genital mycoplasmas have been associated with adverse outcomes of pregnancy, the frequent finding of these organisms in healthy individuals brings into question the validity of mandatory inclusion of these organisms in the screening panel. Although viral STI pathogens and Treponema pallidum - the causative agent of syphilis - may be detected in semen, their presence may be more sensitively detected through antibody testing of the donor. Screening donors for HIV, hepatitis B and syphilis by serology is uniformly recommended in all of the guidelines, but the value of screening either donors or semen samples for cytomegalovirus, herpes simplex viruses and human papilloma viruses is less clear. PMID:18159531

The reliability and validity of the Alcohol Use Disorders Identification Test (AUDIT) in a German general practice population sample.

PubMed

Dybek, Inga; Bischof, Gallus; Grothues, Janina; Reinhardt, Susa; Meyer, Christian; Hapke, Ulfert; John, Ulrich; Broocks, Andreas; Hohagen, Fritz; Rumpf, Hans-Jürgen

2006-05-01

Our goal was to analyze the retest reliability and validity of the Alcohol Use Disorders Identification Test (AUDIT) in a primary-care setting and recommend a cut-off value for the different alcohol-related diagnoses. Participants recruited from general practices (GPs) in two northern German cities received the AUDIT, which was embedded in a health-risk questionnaire. In total, 10,803 screenings were conducted. The retest reliability was tested on a subsample of 99 patients, with an intertest interval of 30 days. Sensitivity and specificity at a number of different cut-off values were estimated for the sample of alcohol consumers (n=8237). For this study, 1109 screen-positive patients received a diagnostic interview. Individuals who scored less than five points in the AUDIT and also tested negative in a second alcohol-related screen were defined as "negative" (n=6003). This definition was supported by diagnostic interviews of 99 screen-negative patients from which no false negatives could be detected. As the gold standard for detection of an alcohol-use disorder (AUD), we used the Munich-Composite International Diagnostic Interview (MCIDI), which is based on Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, criteria. On the item level, the reliability, measured by the intraclass correlation coefficient (ICC), ranged between .39 (Item 9) and .98 (Item 10). For the total score, the ICC was .95. For cut-off values of eight points and five points, 87.5% and 88.9%, respectively, of the AUDIT-positives, and 98.9% and 95.1%, respectively, of the AUDIT-negatives were identically identified at retest, with kappa = .86 and kappa = .81. At the cut-off value of five points, we determined good combinations of sensitivity and specificity for the following diagnoses: alcohol dependence (sensitivity and specificity of .97 and .88, respectively), AUD (.97 and .92), and AUD and/or at-risk consumption (.97 and .91). Embedded in a health-risk questionnaire in primary-care settings, the AUDIT is a reliable and valid screening instrument to identify at-risk drinkers and patients with an AUD. Our findings strongly suggest a lowering of the recommended cut-off value of eight points.

Breast Cancer Screening in a Low Income Managed Care Population

DTIC Science & Technology

1998-10-01

is the only screening test to be demonstrated by prospective clinical trial to decrease cancer mortality (11-13). Its efficiency and relative safety...increase in the utilization of mammography in conjunction with clinical breast exam, the technology continues to be underutilized, especially among certain...Using familiar sites for special program activities e.g. churches, clinic sites; Developing culturally-sensitive information at the appropriate literacy

Neuronal models for evaluation of proliferation in vitro using high content screening.

PubMed

Mundy, William R; Radio, Nicholas M; Freudenrich, Theresa M

2010-04-11

In vitro test methods can provide a rapid approach for the screening of large numbers of chemicals for their potential to produce toxicity (hazard identification). In order to identify potential developmental neurotoxicants, a battery of in vitro tests for neurodevelopmental processes such as cell proliferation, differentiation, growth, and synaptogenesis has been proposed. The development of in vitro approaches for toxicity testing will require choosing a model system that is appropriate to the endpoint of concern. This study compared several cell lines as models for neuronal proliferation. The sensitivities of neuronal cell lines derived from three species (PC12, rat; N1E-115, mouse; SH-SY5Y, human) to chemicals known to affect cell proliferation were assessed using a high content screening system. After optimizing conditions for cell growth in 96-well plates, proliferation was measured as the incorporation of 5-bromo-2'-deoxyuridine (BrdU) into replicating DNA during S phase. BrdU-labeled cells were detected by immunocytochemistry and cell counts were obtained using automated image acquisition and analysis. The three cell lines showed approximately 30-40% of the population in S phase after a 4h pulse of BrdU. Exposure to the DNA polymerase inhibitor aphidicolin for 20 h prior to the 4h pulse of BrdU significantly decreased proliferation in all three cell lines. The sensitivities of the cell lines were compared by exposure to eight chemicals known to affect proliferation (positive controls) and determination of the concentration inhibiting proliferation by 50% of control (I(50)). PC12 cells were the most sensitive to chemicals; 6 out of 8 chemicals (aphidicolin, cadmium, cytosine arabinoside, dexamethasone, 5-fluorouracil, and methylmercury) inhibited proliferation at the concentrations tested. SH-SY5Y cells were somewhat less sensitive to chemical effects, with five out of eight chemicals inhibiting proliferation; dexamethasone had no effect, and cadmium inhibited proliferation only at concentrations that decreased cell viability. Data from the N1E-115 cell line was extremely variable between experiments, and only 4 out of 8 chemicals resulted in inhibition of proliferation. Chemicals that had not been previously shown to alter proliferation (negative controls) did not affect proliferation or cell viability in any cell line. The results show that high content screening can be used to rapidly assess chemical effects on proliferation. Three neuronal cell lines exhibited differential sensitivity to the effect of chemicals on this endpoint, with PC12 cells being the most sensitive to inhibition of proliferation. Published by Elsevier Ireland Ltd.

Stereo tests as a screening tool for strabismus: which is the best choice?

PubMed Central

Ancona, Chiara; Stoppani, Monica; Odazio, Veronica; La Spina, Carlo; Corradetti, Giulia; Bandello, Francesco

2014-01-01

Purpose To compare four stereo tests (Lang I, Lang II, Titmus, and TNO) and assess their effectiveness. The main focus of this study is to identify the most useful stereo test as a challenging tool in the screening of strabismus. Patients and methods A total of 143 Caucasian subjects, 74 males (52%) and 69 females (48%), aged between 4 years and 78 years (mean age 19.09±15.12 years) were examined at our Strabismus Service (Scientific Institute San Raffaele Hospital, Milan, Italy) and included in this observational cross-sectional study. Subjects recruited in this study were either affected by strabismus, including microstrabismic patients, or healthy volunteers. Subjects affected by ophthalmological diseases, other than strabismus, were excluded. All patients underwent both ophthalmological and orthoptic examination, including stereo tests, Hirschberg Corneal Light Reflex Test, Worth Four-Dot Test, the 4 Prism Diopter Base-Out Test, Cover Testing, Bruckner Test, visual acuity, automated refraction under 1% tropicamide cycloplegia and thereafter, posterior pole evaluation. Results All data were processed using the IBM SPSS Statistics, Version 2.0, to perform all statistical calculations. The main finding of this study is that Lang I stereo test achieved the highest sensitivity (89.8%) and specificity (95.2%) in detecting strabismus, including microstrabismus as well, compared to all the other stereoacuity tests. Furthermore, Lang I is the stereo test with the highest positive predictive value and negative predictive value, both greater than 90%. Conclusion The stereo test with the highest sensitivity, specificity, positive predictive value, and negative predictive value is Lang I. These results suggest its applicability as a screening test for strabismus in people older than 4 years. PMID:25419114

Performance of the EUCAST Disk Diffusion Method, the CLSI Agar Screen Method, and the Vitek 2 Automated Antimicrobial Susceptibility Testing System for Detection of Clinical Isolates of Enterococci with Low- and Medium-Level VanB-Type Vancomycin Resistance: a Multicenter Study

PubMed Central

Giske, Christian G.; Haldorsen, Bjørg; Matuschek, Erika; Schønning, Kristian; Leegaard, Truls M.; Kahlmeter, Gunnar

2014-01-01

Different antimicrobial susceptibility testing methods to detect low-level vancomycin resistance in enterococci were evaluated in a Scandinavian multicenter study (n = 28). A phenotypically and genotypically well-characterized diverse collection of Enterococcus faecalis (n = 12) and Enterococcus faecium (n = 18) strains with and without nonsusceptibility to vancomycin was examined blindly in Danish (n = 5), Norwegian (n = 13), and Swedish (n = 10) laboratories using the EUCAST disk diffusion method (n = 28) and the CLSI agar screen (n = 18) or the Vitek 2 system (bioMérieux) (n = 5). The EUCAST disk diffusion method (very major error [VME] rate, 7.0%; sensitivity, 0.93; major error [ME] rate, 2.4%; specificity, 0.98) and CLSI agar screen (VME rate, 6.6%; sensitivity, 0.93; ME rate, 5.6%; specificity, 0.94) performed significantly better (P = 0.02) than the Vitek 2 system (VME rate, 13%; sensitivity, 0.87; ME rate, 0%; specificity, 1). The performance of the EUCAST disk diffusion method was challenged by differences in vancomycin inhibition zone sizes as well as the experience of the personnel in interpreting fuzzy zone edges as an indication of vancomycin resistance. Laboratories using Oxoid agar (P < 0.0001) or Merck Mueller-Hinton (MH) agar (P = 0.027) for the disk diffusion assay performed significantly better than did laboratories using BBL MH II medium. Laboratories using Difco brain heart infusion (BHI) agar for the CLSI agar screen performed significantly better (P = 0.017) than did those using Oxoid BHI agar. In conclusion, both the EUCAST disk diffusion and CLSI agar screening methods performed acceptably (sensitivity, 0.93; specificity, 0.94 to 0.98) in the detection of VanB-type vancomycin-resistant enterococci with low-level resistance. Importantly, use of the CLSI agar screen requires careful monitoring of the vancomycin concentration in the plates. Moreover, disk diffusion methodology requires that personnel be trained in interpreting zone edges. PMID:24599985

Is Erythrocyte Protoporphyrin a Better Single Screening Test for Iron Deficiency Compared to Hemoglobin or Mean Cell Volume in Children and Women?

PubMed

Mei, Zuguo; Flores-Ayala, Rafael C; Grummer-Strawn, Laurence M; Brittenham, Gary M

2017-05-31

Hemoglobin (Hb), mean cell volume (MCV), and erythrocyte protoporphyrin (EP) are commonly used to screen for iron deficiency (ID), but systematic evaluation of the sensitivity and specificity of these tests is limited. The objective of this study is to determine the sensitivity and specificity of Hb, MCV, and EP measurements in screening for ID in preschool children, non-pregnant women 15-49 years of age, and pregnant women. Data from the National Health and Nutrition Examination Surveys (NHANES) (NHANES 2003-2006: n = 861, children three to five years of age; n = 3112, non-pregnant women 15 to 49 years of age. NHANES 1999-2006: n = 1150, pregnant women) were examined for this purpose. Children or women with blood lead ≥10 µg/dL or C-reactive protein (CRP) >5.0 mg/L were excluded. ID was defined as total body iron stores <0 mg/kg body weight, calculated from the ratio of soluble transferrin receptor (sTfR) to serum ferritin (SF). The receiver operating characteristic (ROC) curve was used to characterize the sensitivity and specificity of Hb, MCV, and EP measurements in screening for ID. In detecting ID in children three to five years of age, EP (Area under the Curve (AUC) 0.80) was superior to Hb (AUC 0.62) ( p < 0.01) but not statistically different from MCV (AUC 0.73). In women, EP and Hb were comparable (non-pregnant AUC 0.86 and 0.84, respectively; pregnant 0.77 and 0.74, respectively), and both were better than MCV (non-pregnant AUC 0.80; pregnant 0.70) ( p < 0.01). We concluded that the sensitivity and specificity of EP in screening for ID were consistently superior to or at least as effective as those of Hb and MCV in each population examined. For children three to five years of age, EP screening for ID was significantly better than Hb and similar to MCV. For both non-pregnant and pregnant women, the performance of EP and Hb were comparable; both were significantly superior to MCV.

Validity of a novel computerized screening test system for mild cognitive impairment.

PubMed

Park, Jin-Hyuck; Jung, Minye; Kim, Jongbae; Park, Hae Yean; Kim, Jung-Ran; Park, Ji-Hyuk

2018-06-20

ABSTRACTBackground:The mobile screening test system for screening mild cognitive impairment (mSTS-MCI) was developed for clinical use. However, the clinical usefulness of mSTS-MCI to detect elderly with MCI from those who are cognitively healthy has yet to be validated. Moreover, the comparability between this system and traditional screening tests for MCI has not been evaluated. The purpose of this study was to examine the validity and reliability of the mSTS-MCI and confirm the cut-off scores to detect MCI. The data were collected from 107 healthy elderly people and 74 elderly people with MCI. Concurrent validity was examined using the Korean version of Montreal Cognitive Assessment (MoCA-K) as a gold standard test, and test-retest reliability was investigated using 30 of the study participants at four-week intervals. The sensitivity, specificity, positive predictive value, and negative predictive value (NPV) were confirmed through Receiver Operating Characteristic (ROC) analysis, and the cut-off scores for elderly people with MCI were identified. Concurrent validity showed statistically significant correlations between the mSTS-MCI and MoCA-K and test-rests reliability indicated high correlation. As a result of screening predictability, the mSTS-MCI had a higher NPV than the MoCA-K. The mSTS-MCI was identified as a system with a high degree of validity and reliability. In addition, the mSTS-MCI showed high screening predictability, indicating it can be used in the clinical field as a screening test system for mild cognitive impairment.

Performance of red-green color deficient subjects on the Holmes-Wright lantern (Type A) in photopic viewing.

PubMed

Birch, J

1999-09-01

The Holmes-Wright lantern (Type A) is an approved occupational color vision test for airline pilots in the European Economic Community and for specific occupations in the British Armed Forces. The colors shown are red, green and white signal lights. The Holmes-Wright lantern is a sensitive screening test for red-green color deficiency in photopic viewing and the pass/fail level is similar to that of the Farnsworth Lantern (Falant) if the same scoring method is applied. There were 138 color deficient subjects identified with the Ishihara plates and diagnosed with the Nagel anomaloscope, completed a color vision test battery which included three runs of the nine color pairs of the Holmes-Wright lantern at high brightness in normal room illumination. Screening sensitivity on a single error was found to be 97% compared with the Ishihara plates. Using the Falant scoring method, 20 subjects passed. These were 1 deuteranope, 2 protanomalous trichromats and 17 deuteranomalous trichromats (22% of 88 anomalous trichromats). The mean error score was greater for protans than for deutans but the mean number of qualitative error categories was smaller. Green/white confusions were the most frequent errors. It was not possible to predict who would pass the lantern test from other test results but all subjects with a Nagel anomaloscope matching range > 15 scale units who failed the Farnsworth D15 test or were grading as moderate/severe with the American Optical Company (Hardy, Rand and Rittler) plates failed. The Holmes-Wright lantern is a sensitive screening test for red-green color deficiency. Although a similar percentage of anomalous trichromats fail the Holmes-Wright lantern as fail the Falant, if the same scoring method is used, the superior correlation between the Holmes-Wright result and other color vision tests designed to grade the severity of color deficiency suggests that the two lantern results are not equivalent.