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ObjectiveWe adapted the Quality Assessment of Diagnostic Accuracy Studies 2 (QUADAS-2) tool for studies of cervical cancer screening and management and used the adapted tool to evaluate the quality of studies included in a systematic review supporting the 2019 Risk-Based Management Consensus Guidelines.MethodsWe evaluated the quality of all studies included in our systematic review for postcolposcopy (n = 5) and posttreatment (n = 23) surveillance using QUADAS-2 criteria. Subsequently, we adapted signaling questions to indications of cervical cancer screening and management. An iterative process was carried out to evaluate interrater agreement between 2 study authors (M.A.C. and N.W.). Discrepant ratings were discussed, and criteria were adapted accordingly. We also evaluated the influence of study quality on risk estimates and between study variation using stratified subgroup meta-analyses.ResultsTwelve signaling questions for bias assessment that were adapted to or newly developed for cervical cancer screening and management are described here. Interrater agreement on bias assessment increased from 70% to 83% during the adaptation process. Detailed assessment of bias and applicability showed that all studies on postcolposcopy management and 90% of studies on posttreatment management had high risk of bias in at least 1 domain. Most commonly, high risk of bias was observed for the patient selection domain, indicating the heterogeneity of study designs and clinical practice in reported studies.ConclusionsThe adapted QUADAS-2 will have broad application for researchers, evidence evaluators, and journals who are interested in designing, conducting, evaluating, and publishing studies for cervical cancer screening and management.

In this review, we focused on the applicability of artificial intelligence (AI) for opportunistic abdominal aortic aneurysm (AAA) detection in computed tomography (CT). We used the academic search system PubMed as the primary source for the literature search and Google Scholar as a supplementary source of evidence. We searched through 2 February 2022. All studies on automated AAA detection or segmentation in noncontrast abdominal CT were included. For bias assessment, we developed and used an adapted version of the QUADAS-2 checklist. We included eight studies with 355 cases, of which 273 (77%) contained AAA. The highest risk of bias and level of applicability concerns were observed for the "patient selection" domain, due to the 100% pathology rate in the majority (75%) of the studies. The mean sensitivity value was 95% (95% CI 100–87%), the mean specificity value was 96.6% (95% CI 100–75.7%), and the mean accuracy value was 95.2% (95% CI 100–54.5%). Half of the included studies performed diagnostic accuracy estimation, with only one study having data on all diagnostic accuracy metrics. Therefore, we conducted a narrative synthesis. Our findings indicate high study heterogeneity, requiring further research with balanced noncontrast CT datasets and adherence to reporting standards in order to validate the high sensitivity value obtained. [ABSTRACT FROM AUTHOR]

Study Design: Systematic review.Objective: To determine the validity of the Hoffmann sign for the detection of degenerative cervical myelopathy (DCM) for patients presenting with cervical complaints.Summary Of Background Data: While physical examination maneuvers are often used to diagnose DCM, no previous review has synthesized diagnostic accuracy data.Methods: Medline, Embase, and HealthStar were searched for articles from January 1, 1947 to March 1, 2017 using the following terms: Spinal Cord Diseases, Spinal Cord Compression, Cervical Vertebrae, Signs and Symptoms, Physical Examination, Epidemiologic studies, Epidemiologic Research Design, Predictive Value of Tests, and Myelopathy. The Quality Assessment of Diagnostic Accuracy Studies (QUADAS) checklist was applied to determine the level of evidence. Articles included were published in English or French language, rated as QUADAS level 3 or higher with a minimum 10 patients presenting with cervical complaints having undergone the Hoffman sign. Excluded studies recruited patients with a nondegenerative type of cervical myelopathy, and/or no evaluation with magnetic resonance imaging.Results: A total of 589 articles were selected for review. Following the application of inclusion and exclusion criteria, 45 articles were analyzed using the QUADAS checklist. Only of three articles were of QUADAS quality 3 or higher. Analysis of combined data from 2/3 studies indicated that the Hoffman sign has a positive likelihood ratio of 2.2 (95% CI 1.5-3.3) and a negative likelihood ratio of 0.63 (95% CI 0.5-0.8).Conclusion: A positive Hoffman alone is unlikely to lead to more than a small change in estimated probability of DCM as compared with the gold standard test (magnetic resonance imaging). Variability in results across individual studies may result from differences in study design. There are insufficient data to support use of the Hoffman sign alone to confirm or refute a diagnosis of DCM.Level Of Evidence: 1. [ABSTRACT FROM AUTHOR]

Commercial point-of-care (POC) diagnostic tests for Group A Streptococcus , Streptococcus pneumoniae , and influenza virus have large potential diagnostic and financial impact. Many published reports on test performance, often funded by diagnostics companies, are prone to bias. The Standards for Reporting of Diagnostic Accuracy (STARD 2015) are a protocol to encourage accurate, transparent reporting. The Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) tool evaluates risk of bias and transportability of results. We used these tools to evaluate diagnostic test accuracy studies of POC studies for three respiratory pathogens. For the 96 studies analysed, compliance was <25% for 14/34 STARD 2015 standards, and 3/7 QUADAS-2 domains showed a high risk of bias. All reports lacked reporting of at least one criterion. These biases should be considered in the interpretation of study results. [ABSTRACT FROM AUTHOR]

Objective: to evaluate the quality of diagnostic accuracy studies related to Physiotherapy with the STARD statement and QUADAS-2 tool. Material and method: a research was performed with Pubmed/MEDLINE data base following guidelines by the authors Haynes and Leeflang, and using specific terms of diagnostic accuracy (sensitivity, specificity, diagnostic, predictive value, likelihood, ROC, Physical Therapy) without using filters and its specificity was improved by adding terms used in this kind of study. Finally quality of works was evaluated with the Quality Assessment Tool for Diagnostic Accuracy Studies (QUADAS-2; 2010) and also with the STARD initiative (Standards for Reporting of Diagnostic Accuracy). Results and discussion: a total of 282 articles were located and 257 of them were excluded. The final sample consisted of 25 works. The majority of examined articles, erroneously follow the recommendations proposed in QUADAS-2. In general, observing obtained data, it appears that STARD have been better applied to QUADAS-2. However the lack of a proper methodological application in the results section is evidenced. Conclusions: the items in the STARD guide are used correctly in most of the sections but not in methodology and results exposition items. The analysis with QUADAS-2 tool shows that there is a high risk of bias in most of the articles. [ABSTRACT FROM AUTHOR]

While oral appliances (OA) have demonstrated good efficacy in patients ranging from mild to severe levels of obstructive sleep apnea (OSA), this form of treatment is not completely effective in all patients. As a successful treatment response is not dependent solely on apnea hypopnea index severity, the prediction of OA treatment efficacy is of key importance for efficient disease management. This systematic review aims to investigate the accuracy of a variety of clinical and experimental tests for predicting OA treatment outcomes in OSA. A systematic literature review was conducted and the quality of the selected studies was assessed using the quality assessment of diagnostic accuracy studies (QUADAS-2) tool. Some 17 studies involving various prediction methods were included in this review. The predictive accuracy varied depending on the definitions of treatment success used as well as the type of index test. The studies with the best predictive accuracy and lowest risk of bias and concerns of applicability used a multisensor catheter. While a remotely controlled mandibular positioner study showed high accuracy, there was a high risk of bias. The available information on the validity of predictive index tests is very useful in clinical practice and allows for greater disease management efficiency. [ABSTRACT FROM AUTHOR]

Objectives With rapidly increasing numbers of publications, assessments of study quality, reporting quality, and classification of studies according to their level of evidence or developmental stage have become key issues in weighing the relevance of new information reported. Diagnostic marker studies are often criticized for yielding highly discrepant and even controversial results. Much of this discrepancy has been attributed to differences in study quality. So far, numerous tools for measuring study quality have been developed, but few of them have been used for systematic reviews and meta-analysis. This is owing to the fact that most tools are complicated and time consuming, suffer from poor reproducibility, and do not permit quantitative scoring. Methods The International Bladder Cancer Network (IBCN) has adopted this problem and has systematically identified the more commonly used tools developed since 2000. Results In this review, those tools addressing study quality (Quality Assessment of Studies of Diagnostic Accuracy and Newcastle-Ottawa Scale), reporting quality (Standards for Reporting of Diagnostic Accuracy), and developmental stage (IBCN phases) of studies on diagnostic markers in bladder cancer are introduced and critically analyzed. Based upon this, the IBCN has launched an initiative to assess and validate existing tools with emphasis on diagnostic bladder cancer studies. Conclusions The development of simple and reproducible tools for quality assessment of diagnostic marker studies permitting quantitative scoring is suggested. [ABSTRACT FROM AUTHOR]

Objectives: To provide an overview of reporting and methodological quality in diagnostic test accuracy (DTA) studies in the musculoskeletal field and evaluate the use of the QUality Assessment of Diagnostic Accuracy Studies (QUADAS) checklist. Study Design and Setting: A literature review identified all systematic reviews that evaluated the accuracy of clinical tests to diagnose musculoskeletal conditions and used the QUADAS checklist. Two authors screened all identified reviews and extracted data on the target condition, index tests, reference standard, included studies, and QUADAS items. A descriptive analysis of the QUADAS checklist was performed, along with Rasch analysis to examine the construct validity and internal reliability. Results: A total of 19 systematic reviews were included, which provided data on individual items of the QUADAS checklist for 392 DTA studies. In the musculoskeletal field, uninterpretable or intermediate test results are commonly not reported, with 175 (45%) studies scoring ''no'' to this item. The proportion of studies fulfilling certain items varied from 22% (item 11) to 91% (item 3). The interrater reliability of the QUADAS checklist was good and Rasch analysis showed excellent construct validity and internal consistency. Conclusion: This overview identified areas where the reporting and performance of diagnostic studies within the musculoskeletal field can be improved. [ABSTRACT FROM AUTHOR]

Background Drawing conclusions from systematic reviews of test accuracy studies without considering the methodological quality (risk of bias) of included studies may lead to unwarranted optimism about the value of the test(s) under study. We sought to identify to what extent the results of quality assessment of included studies are incorporated in the conclusions of diagnostic accuracy reviews. Methods We searched MEDLINE and EMBASE for test accuracy reviews published between May and September 2012. We examined the abstracts and main texts of these reviews to see whether and how the results of quality assessment were linked to the accuracy estimates when drawing conclusions. Results We included 65 reviews of which 53 contained a meta-analysis. Sixty articles (92%) had formally assessed the methodological quality of included studies, most often using the original QUADAS tool (n = 44, 68%). Quality assessment was mentioned in 28 abstracts (43%); with a majority (n = 21) mentioning it in the methods section. In only 5 abstracts (8%) were results of quality assessment incorporated in the conclusions. Thirteen reviews (20%) presented results of quality assessment in the main text only, without further discussion. Forty-seven reviews (72%) discussed results of quality assessment; the most frequent form was as limitations in assessing quality (n = 28). Only 6 reviews (9%) further linked the results of quality assessment to their conclusions, 3 of which did not conduct a meta-analysis due to limitations in the quality of included studies. In the reviews with a meta-analysis, 19 (36%) incorporated quality in the analysis. Eight reported significant effects of quality on the pooled estimates; in none of them these effects were factored in the conclusions. Conclusion While almost all recent diagnostic accuracy reviews evaluate the quality of included studies, very few consider results of quality assessment when drawing conclusions. The practice of reporting systematic reviews of test accuracy should improve if readers not only want to be informed about the limitations in the available evidence, but also on the associated implications for the performance of the evaluated tests. [ABSTRACT FROM AUTHOR]

Assessing the quality of included studies is a vital step in undertaking a systematic review. The recently revised Quality Assessment of Diagnostic Accuracy Studies (QUADAS) tool (QUADAS-2), which is the only validated quality assessment tool for diagnostic accuracy studies, does not include specific criteria for assessing comparative studies. As part of an assessment that included comparative diagnostic accuracy studies, we used a modified version of QUADAS-2 to assess study quality. We modified QUADAS-2 by duplicating questions relating to the index test, to assess the relevant potential sources of bias for both the index test and comparator test. We also added review-specific questions. We have presented our modified version of QUADAS-2 and outlined some key issues for consideration when assessing the quality of comparative diagnostic accuracy studies, to help guide other systematic reviewers conducting comparative diagnostic reviews. Until QUADAS is updated to incorporate assessment of comparative studies, QUADAS-2 can be used, although modification and careful thought is required. It is important to reflect upon whether aspects of study design and methodology favour one of the tests over another. © 2013 Crown copyright. [ABSTRACT FROM AUTHOR]

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

Abstract: Background: Positron emission tomography (PET) imaging using the radiotracer 18F-Fluorothymidine (FLT) has been proposed as an imaging biomarker of tumour proliferation. If FLT-PET can be established as such it will provide a non-invasive, quantitative measurement of tumour proliferation across the entire tumour. Results from validation studies have so far been conflicting with some studies confirming a good correlation between FLT uptake and Ki-67 score and others presenting negative results. Methods: Firstly we performed a systematic review of published studies between 1998 and 2011 that explored the correlation between FLT uptake and Ki-67 score and examined possible variations in the methods used. Studies were eligible if they: (a) included patients with cancer, (b) investigated the correlation between Ki-67 measured by immunohistochemistry and FLT uptake measured with PET scanning, and (c) were published as a full paper in a peer-reviewed scientific journal. Secondly a meta-analysis of the correlation coefficient values reported from each study was performed. Correlation coefficient (r) values were extracted from each study and 95% confidence intervals (CIs) were calculated after applying Fisher’s z transformation. For subgroup analysis, studies were classified by the index used to characterise Ki-67 expression (average or maximum expression), the nature of the sample (whole specimen or biopsy) and the cancer type. Findings: Twenty-seven studies were identified as eligible for the meta-analysis. In the studies we examined there were variations in aspects of the methods and reporting. The meta-analysis showed that given an appropriate study design the FLT/Ki-67 correlation is significant and independent of cancer type. Specifically subgroup analysis showed that FLT/Ki-67 correlation was high in studies measuring the Ki-67 average expression regardless of use of surgery or biopsy samples (r =0.70, 95% CI=0.43–0.86, p <0.001). Of the studies that measured Ki-67 maximum expression, only those that used the whole surgical specimen provided a significant r value (r =0.72, 95% CI=0.54–0.84, p <0.001). Studies that used biopsy samples for Ki-67 maximum measurements did not produce a significant r value (r =0.04, 95% CI=−0.18–0.26, p =0.71). In terms of the cancer type subgroup analysis there is sufficient data to support a strong FLT/Ki-67 correlation for brain, lung and breast cancer. No publication bias was detected. Interpretation: This systematic review and meta-analysis highlights the importance of the methods used in validation studies comparing FLT-PET imaging with the biomarker Ki-67. The correlation is significant and independent of cancer type provided a study design that uses Ki-67 average measurements, regardless of nature of sample, or whole surgical samples when measuring Ki-67 maximum expression. Sufficient data to support a strong correlation for brain, lung and breast cancer exist. However, larger, prospective studies with improved study design are warranted to validate these findings for the rest of the cancer types. [Copyright &y& Elsevier]

There has been an increase in the number of systematic reviews of diagnostic tests, which has resulted in the introduction of two checklists: statement for reporting of diagnostic accuracy (STARD) and quality assessment of diagnostic accuracy studies (QUADAS). To examine the validity and usefulness of QUADAS when applied to diagnostic accuracy studies using psychometric instruments and to examine the quality in reporting of these studies during practical application of the checklist. Two reviewers independently rated the quality of 54 studies using QUADAS. The proportion of agreement was used to assess overall agreement and individual agreement of QUADAS items between reviewers. The overall agreement between the two reviewers for all QUADAS items combined was 85.7%. The proportion of agreement between reviewers for each item ranged from just over 57–100% and was over 80% for 8 of the items. The poorest agreement was associated with the items for selection criteria, indeterminate results and withdrawals. None of the studies adequately reported all relevant information to enable all QUADAS item to be scored as ‘yes’. Overall QUADAS was relatively easy to use and appears to be an acceptable tool for appraising the quality of diagnostic accuracy studies using psychometric instruments. The application of QUADAS was hampered by the poor quality of reporting encountered. [ABSTRACT FROM AUTHOR]

Abstract: Objectives: To adapt the Quality Assessment of Diagnostic Accuracy Assessment (QUADAS) to the particular methodological challenges posed by research on ‘-omics’-based diagnostic tests. Design and methods: We generated new guidelines by appraising the suitability of each criterion from QUADAS to ‘-omics’-based diagnostic research, and by adding new items that addressed specific sources of error. In addition, we defined four phases in the evaluation of a diagnostic test. Results: Twelve of the 14 criteria from QUADAS were retained in the new tool. The items relating to selection criteria and the description of the test were reformulated, and the criteria about external validation and the availability of clinical data were applied only in studies in the last research phase. Four new items were incorporated to QUADOMICS related to pre-analytical conditions and methods to avoid overfitting. Conclusions: QUADOMICS is an adaptation of QUADAS to the special nature of ‘-omics’-based diagnostic research. The tool adds new items that assess quality issues specific to this research, and may enhance the application of ‘-omics’-based discoveries to clinical \and public health practice. [Copyright &y& Elsevier]

Background Atopic dermatitis (AD) has a wide spectrum of dermatological manifestations and despite various validated sets of diagnostic criteria that have been developed over the past decades, there is disagreement about its definition. Nevertheless, clinical studies require valid diagnostic criteria for reliable and reproducible results. Objective To summarize the evidence concerning the validity of diagnostic criteria for AD. Methods All data sources were identified through searches on Medline, Embase and Cochrane databases. The Quality Assessment of Diagnostic Accuracy tool (QUADAS) was used. Results are presented in a receiver operating characteristic (ROC) plot. Results Out of the 20 articles that met the criteria, 27 validation studies were identified. In two studies concerning Hanifin and Rajka diagnostic criteria sensitivity and specificity ranged from 87·9% to 96·0% and from 77·6% to 93·8%, respectively. Nineteen validation studies of the U.K. diagnostic criteria showed sensitivity and specificity ranging from 10% to 100% and 89·3% to 99·1%, respectively. Three validation studies concerning the Schultz-Larsen criteria showed sensitivity from 88% to 94·4% and specificity from 77·6% to 95·9%. In one article concerning the criteria of Diepgen, the sensitivity ranged from 83·0% to 87·7% and the specificity from 83·9% to 87·0%. One article studied the Kang and Tian criteria and reported 95·5% sensitivity and 100% specificity. One article validating the International Study of Asthma and Allergies in Childhood (ISAAC) criteria showed a positive and negative predictive value of 48·8% and 91·1%, respectively. Conclusion With this systematic review of the existing sets of diagnostic criteria for AD a varying number of validation studies with varying methodological quality was found. The U.K. diagnostic criteria are the most extensively validated. However, improvement of methodological design for validation studies and uniformity in well-validated and applicable diagnostic criteria are needed to improve future intervention studies and to compare study results. [ABSTRACT FROM AUTHOR]

Abstract: Objective: To determine the accuracy of clinical features in diagnosing vertebral fracture in low back pain patients and assess the psychometric properties of the Quality Assessment of Studies of Diagnostic Accuracy Included in Systematic Reviews (QUADAS) scale. Study Design and Setting: A diagnostic systematic review was performed on all available records in MEDLINE, CINAHL, and EMBASE. Studies were considered eligible if they investigated clinical features associated with vertebral fracture in a cohort of low back pain patients. All eligible studies were assessed for methodological quality using the QUADAS scale, and two authors extracted true-positive, true-negative, false-positive, and false-negative data for each clinical feature. Results: Twelve studies were identified by the review, investigating 51 clinical features. Five clinical features were useful to raise or lower the probability of vertebral fracture: age >50 years (likelihood ratio [LR]+=2.2, LR−=0.34), female gender (LR+=2.3, LR−=0.67), major trauma (LR+=12.8, LR−=0.37), pain and tenderness (LR+=6.7, LR−=0.44), and a distracting painful injury (LR+=1.7, LR−=0.78). The QUADAS had low internal consistency, and only three items had high inter-rater reliability. There was inadequate reporting of many methodological quality items. Conclusion: Five clinical features were identified that can be used to screen for vertebral fracture. The psychometric properties of the QUADAS scale raise concerns about its use to rate the quality of low back pain diagnosis studies. [Copyright &y& Elsevier]

Clinical special tests are a mainstay of orthopaedic diagnosis. Within the context of the evidence-based practice paradigm, data on the diagnostic accuracy of these special tests are frequently used in the decision-making process when determining the diagnosis, prognosis, and selection of appropriate intervention strategies. However, the reported diagnostic utility of these tests is significantly affected by study methodology of diagnostic accuracy studies. Methodological shortcomings can influence the outcome of such studies, and this in turn will affect the clinician's interpretation of diagnostic findings. The methodological issues associated with studies investigating the diagnostic utility of clinical tests have mandated the development of the STARD (Standards for Reporting of Diagnostic Accuracy) and QUADAS (Quality Assessment of Diagnostic Accuracy Studies) criterion lists. The purpose of this paper is to outline the STARD and QUADAS criterion lists and to discuss how these methodological quality assessment tools can assist the clinician in ascertaining clinically useful information from a diagnostic accuracy study. [ABSTRACT FROM AUTHOR]

Objective: To determine whether methodological and reporting quality are associated with surrogate measures of publication impact in the field of dementia biomarker studies., Methods: We assessed dementia biomarker studies included in a previous systematic review in terms of methodological and reporting quality using the Quality Assessment of Diagnostic Accuracy Studies (QUADAS) and Standards for Reporting of Diagnostic Accuracy (STARD), respectively. We extracted additional study and journal-related data from each publication to account for factors shown to be associated with impact in previous research. We explored associations between potential determinants and measures of publication impact in univariable and stepwise multivariable linear regression analyses., Outcome Measures: We aimed to collect data on four measures of publication impact: two traditional measures-average number of citations per year and 5-year impact factor of the publishing journal and two alternative measures-the Altmetric Attention Score and counts of electronic downloads., Results: The systematic review included 142 studies. Due to limited data, Altmetric Attention Scores and electronic downloads were excluded from the analysis, leaving traditional metrics as the only analysed outcome measures. We found no relationship between QUADAS and traditional metrics. Citation rates were independently associated with 5-year journal impact factor (β=0.42; p<0.001), journal subject area (β=0.39; p<0.001), number of years since publication (β=-0.29; p<0.001) and STARD (β=0.13; p<0.05). Independent determinants of 5-year journal impact factor were citation rates (β=0.45; p<0.001), statement on conflict of interest (β=0.22; p<0.01) and baseline sample size (β=0.15; p<0.05)., Conclusions: Citation rates and 5-year journal impact factor appear to measure different dimensions of impact. Citation rates were weakly associated with completeness of reporting, while neither traditional metric was related to methodological rigour. Our results suggest that high publication usage and journal outlet is not a guarantee of quality and readers should critically appraise all papers regardless of presumed impact., Competing Interests: Competing interests: AHN-S, RM, TQ have all published methodological and reporting guidance around raising standards in dementia test accuracy research., (© Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.)

Background & Aims: US guidelines recommend surveillance of patients with Barrett’s esophagus (BE) to detect dysplasia. BE conventionally is monitored via white-light endoscopy (WLE) and a collection of random biopsy specimens. However, this approach does not definitively or consistently detect areas of dysplasia. Advanced imaging technologies can increase the detection of dysplasia and cancer. We investigated whether these imaging technologies can increase the diagnostic yield for the detection of neoplasia in patients with BE, compared with WLE and analysis of random biopsy specimens. Methods: We performed a systematic review, using Medline and Embase, to identify relevant peer-review studies. Fourteen studies were included in the final analysis, with a total of 843 patients. Our metameter (estimate) of interest was the paired–risk difference (RD), defined as the difference in yield of the detection of dysplasia or cancer using advanced imaging vs WLE. The estimated paired-RD and 95% confidence interval (CI) were obtained using random-effects models. Heterogeneity was assessed by means of the Q statistic and the I 2 statistic. An exploratory meta-regression was performed to look for associations between the metameter and potential confounders or modifiers. Results: Overall, advanced imaging techniques increased the diagnostic yield for detection of dysplasia or cancer by 34% (95% CI, 20%–56%; P < .0001). A subgroup analysis showed that virtual chromoendoscopy significantly increased the diagnostic yield (RD, 0.34; 95% CI, 0.14–0.56; P < .0001). The RD for chromoendoscopy was 0.35 (95% CI, 0.13–0.56; P = .0001). There was no significant difference between virtual chromoendoscopy and chromoendoscopy, based on Student t test analysis (P = .45). Conclusions: Based on a meta-analysis, advanced imaging techniques such as chromoendoscopy or virtual chromoendoscopy significantly increase the diagnostic yield for identification of dysplasia or cancer in patients with BE. [Copyright &y& Elsevier]

Abstract: Background: Although recent diagnostic criteria for Alzheimer''s disease propose the use of biomarkers, validation of these biomarkers by diagnostic test accuracy studies is a necessary first step, followed by the synthesis of the evidence from these studies in systematic reviews and meta-analyses. The quality of the resulting evidence depends on the number and size of the primary studies, their quality, and the adequacy of their reporting. This systematic review assesses the weight and quality of the evidence available from primary diagnostic test accuracy studies. Methods: A MEDLINE search was performed in August 2011 to identify all potentially relevant publications relating to the biomarkers β-amyloid, tau, positron emission tomography (18F-fluorodeoxyglucose or ligands for amyloid), or magnetic resonance imaging (MRI). The reporting and methodology were assessed using the Standards for Reporting of Diagnostic Accuracy and Quality Assessment of Diagnostic Accuracy Studies assessment tools, respectively. Because clinical progression to dementia is the most commonly used reference standard, this review focuses on participants with objective cognitive impairment but no dementia at baseline. Results: Of the 19,104 published references identified by the search, 142 longitudinal studies relating to the biomarkers of interest were identified, which included subjects who had objective cognitive impairment but no dementia at baseline. The highest number of studies (n = 70) and of participants (n = 4722) related to structural MRI. MRI also yielded the highest number of studies with extractable data for meta-analysis (n = 32 [46% of all structural MRI studies]), followed by cerebrospinal fluid tau (n = 24 [73%]). There were few studies on positron emission tomography ligands for amyloid having suitable data for meta-analysis (n = 4). There was considerable variation across studies in reporting outcomes, methods of blinding and selection, means of accounting for indeterminate or missing values, the interval between the test and assessments, and the determination of test thresholds. Conclusions: The body of evidence for biomarkers is not large and is variable across the different types of biomarkers. Important information is missing from many study reports, highlighting the need for standardization of methodology and reporting to improve the rigor of biomarker validation. [Copyright &y& Elsevier]

Background: MicroRNAs (miRNAs) have been reported to be aberrantly expressed in patients with cancer. Many studies have shown that circulating miRNAs could play potential roles as diagnostic and prognostic biomarkers of cancers. The aim of this meta-analysis is to summarize the role of circulating miR-21 as a biomarker in patients with a variety of carcinomas., Material and Methods: Eligible studies were identified and assessed for quality through multiple search strategies. For diagnostic meta-analysis, the sensitivity, specificity, and other measures of miR-21 in the diagnosis of cancer were pooled using bivariate random-effects approach models. For prognostic meta-analysis, pooled hazard ratios (HRs) of circulating miR-21 for survival were calculated., Results: A total of 36 studies dealing with various carcinomas were included for the systemic review. Among them, 23 studies were finally enrolled in the global meta-analysis (17 studies for diagnosis and 6 studies for prognosis). For diagnostic meta-analysis, the overall pooled results for sensitivity, specificity, positive likelihood ratio (LRP), negative likelihood ratios (LRN) and diagnostic odds ratio (DOR) were 75.7% (95% CI: 67.1%-82.6%), 79.3% (95% CI: 74.2%-83.5%), 3.65 (95% CI: 2.83-4.70), 0.31 (95% CI: 0.22-0.43), and 11.88 (95% CI: 6.99-20.19), respectively. For prognostic meta-analysis, the pooled HR of higher miR-21 expression in circulation was 2.37 (95% CI: 1.83-3.06, P<0.001), which could significantly predict poorer survival in general carcinomas. Importantly, subgroup analysis suggested that higher expression of miR-21 correlated with worse overall survival (OS) significantly in carcinomas of digestion system (HR, 5.77 [95% CI: 2.65-12.52])., Conclusions: Our findings suggest that circulating miR-21 may not suitable to be a diagnostic biomarker, but it has a prognostic value in patients with cancer., (© 2013.)

Objectives: Bladder tumor fibronectin (BTF) has been related as a promising biomarker for the early diagnosis of bladder tumor. The meta-analysis was used to establish the diagnostic value of bladder tumor fibronectin in diagnosing bladder tumor., Methods: Relevant literatures evaluating the value of BTF in the diagnosis of bladder tumor were searched in PubMed, Embase, China National Knowledge Infrastructure (CNKI), Technology of Chongqing (VIP), and Wan Fang Data. Summary estimates were used to evaluate the value of BTF in the diagnosis of bladder tumor by using the Meta-DiSc and STATA 11.0 statistical software., Results: The meta-analysis included 5 studies (649 patients, 291 controls). The summary estimates revealed that the pooled sensitivity was 81% (95% confidence interval [CI]: 74%-85.1%) and specificity was 80% (95%CI 74%-84%). In addition, the area under the summary ROC curve (AUC) was 0.86 (95%CI 0.82-0.89)., Conclusion: BTF is a potential marker for the diagnosis of bladder tumor, and more prospective studies are needed in the future., (Copyright © 2013 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.)

Background: Differential diagnosis of pancreatic solid masses with EUS-guided FNA (EUS-FNA) is still challenging in about 15% of cases. Mutation of the K-ras gene is present in over 75% of pancreatic adenocarcinomas (PADC)., Objective: To assess the accuracy of K-ras gene mutation analysis for diagnosing PADC., Design: We systematically searched the electronic databases for relevant studies published. Data from selected studies underwent meta-analysis by use of a bivariate model providing a pooled value for sensitivity, specificity, diagnostic odds ratio, and summary receiver operating characteristic curve., Setting: Meta-analysis of 8 prospective studies., Patients: Total of 931 patients undergoing EUS-FNA for diagnosis of pancreatic solid masses., Intervention: K-ras mutation analysis., Main Outcome Measurements: Diagnostic accuracy of K-ras mutation analysis and of combined diagnostic strategy by using EUS-FNA and K-ras mutation analysis in the diagnosis of PADC., Results: The pooled sensitivity of EUS-FNA for the differential diagnosis of PADC was 80.6%, and the specificity was 97%. Estimated sensitivity and specificity were 76.8% and 93.3% for K-ras gene analysis, respectively, and 88.7% and 92% for combined EUS-FNA plus K-ras mutation analysis. Overall, K-ras mutation testing applied to cases that were inconclusive by EUS-FNA reduced the false-negative rate by 55.6%, with a false-positive rate of 10.7%. Not repeating EUS-FNA in cases in which mutation testing of the K-ras gene is inconclusive would reduce the repeat-biopsy rate from 12.5% to 6.8%., Limitations: Small number of studies and between-study heterogeneity., Conclusion: K-ras mutation analysis can be useful in the diagnostic work-up of pancreatic masses, in particular when tissue obtained by EUS-FNA is insufficient, and the diagnosis inconclusive., (Copyright © 2013 American Society for Gastrointestinal Endoscopy. Published by Mosby, Inc. All rights reserved.)

Paramount to efficient and effective care is the determination of an accurate diagnosis that leads to the proper referral and/or intervention. In an effort to improve the clinical utility of diagnostic accuracy calculations, researchers have promoted the use of the mnemonics SpPIn (if specificity is high, a positive test rules in pathology) and SnNOut (if sensitivity is high, a negative test rules out pathology). Using examples from diagnostic accuracy studies and a review of pertinent literature, this clinimetrics corner outlines additional considerations for clinicians when consuming research in this area. The paper has three foci. First, sensitivity, specificity, and other estimates of the diagnostic accuracy of dichotomous physical examination tests should be viewed as estimates with confidence when those estimates are expressed as confidence intervals. Second, appropriate power must be considered when evaluating each study. Last, the quality of a diagnostic accuracy study can affect the generalizibility of the results to practice environments.