Diagnostic Test Accuracy Meta-analysis Research Articles

Recommendations for reporting of systematic reviews and meta-analyses of diagnostic test accuracy: a systematic review

BackgroundThis study is to perform a systematic review of existing guidance on quality of reporting and methodology for systematic reviews of diagnostic test accuracy (DTA) in order to compile a list of potential items that might be included in a reporting guideline for such reviews: Preferred Reporting Items for Systematic Reviews and Meta-Analyses of Diagnostic Test Accuracy (PRISMA-DTA).MethodsStudy protocol published on EQUATOR website. Articles in full text or abstract form that reported on any aspect of reporting systematic reviews of diagnostic test accuracy were eligible for inclusion. We used the Ovid platform to search Ovid MEDLINE®, Ovid MEDLINE® In-Process & Other Non-Indexed Citations and Embase Classic+Embase through May 5, 2016. The Cochrane Methodology Register in the Cochrane Library (Wiley version) was also searched. Title and abstract screening followed by full-text screening of all search results was performed independently by two investigators. Guideline organization websites, published guidance statements, and the Cochrane Handbook for Diagnostic Test Accuracy were also searched. Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) and Standards for Reporting Diagnostic Accuracy (STARD) were assessed independently by two investigators for relevant items.ResultsThe literature searched yielded 6967 results; 386 were included after title and abstract screening and 203 after full-text screening. After reviewing the existing literature and guidance documents, a preliminary list of 64 items was compiled into the following categories: title (three items); introduction (two items); methods (35 items); results (13 items); discussion (nine items), and disclosure (two items).ConclusionItems on the methods and reporting of DTA systematic reviews in the present systematic review will provide a basis for generating a PRISMA extension for DTA systematic reviews.

Diagnostic accuracy of molecular tumor profiling in determining the tissue of origin in adult patients with cancer of unknown primary: A meta-analysis.

e23092 Background: Appropriate cancer treatment requires determination of the primary site of origin. The standard of care for diagnosing Cancer of unknown primary (CUP) based on the 2016 NCCN Guidelines is a comprehensive clinical work-up including biopsy and immunohistochemistry (IHC). However, IHC was able to identify a primary tumor in only 25% of CUP. Molecular tumor profiling (MTP) validation studies demonstrated sensitivities of 74-89% and specificities of 95-99%. Only a few studies with small sample sizes using MTP to diagnose the primary in CUP have been performed yielding variable results. This study aims to evaluate the diagnostic accuracy of MTP in determining the tissue of origin in adult patients with CUP. Methods: Literature search included articles published in any language indexed in MEDLINE and Cochrane. A Google Scholar search and a review of all published articles’ references were performed. Unpublished studies and abstracts from conference proceedings were also reviewed. Studies involving adult patients with CUP who underwent both MTP and clinical evaluation with IHC were identified. Articles were included if they had primary data sufficient to calculate both sensitivity and specificity. Methodological qualities of the included studies were evaluated using the QUADAS-2 tool. Data was analyzed using Review Manager 5.3 and MetaDiSc 1.4. Results: Seven studies with 549 patients were analyzed. MTP was found to have a pooled sensitivity of 89% (95% CI 0.85-0.92)and pooled specificity of 74% (95% CI 0.67-0.80)with pooled positive and negative likelihood ratios of 2.97 (95% CI 1.17-7.63) and 0.20 (95% CI 0.07-0.51), respectively. Area under the curve was measured to be 0.9107. Conclusions: This meta-analysis suggests that MTP could be useful in determining the tissue of origin in adult patients with CUP. With an area under the curve of 0.9107, it is an excellent diagnostic test. The results showed considerable heterogeneity as expected in meta-analyses of diagnostic test accuracy. In this case, it may be due to variability among the MTP assays used which may reflect different cutoffs.

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

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.

Diagnostic accuracy of molecular tumor profiling in determining the tissue of origin in adult patients with cancer of unknown primary: A meta-analysis.

20 Background: Appropriate cancer treatment requires determination of the primary site of origin. The standard of care for diagnosing Cancer of unknown primary (CUP) based on the 2016 NCCN Guidelines is a comprehensive clinical work-up including biopsy and immunohistochemistry (IHC). However, IHC was able to identify a primary tumor in only 25% of CUP. Molecular tumor profiling (MTP) validation studies demonstrated sensitivities of 74-89% and specificities of 95-99%. Only a few studies with small sample sizes using MTP to diagnose the primary in CUP have been performed yielding variable results. This study aims to evaluate the diagnostic accuracy of MTP in determining the tissue of origin in adult patients with CUP. Methods: Literature search included articles published in any language indexed in MEDLINE and Cochrane. A Google Scholar search and a review of all published articles’ references were performed. Unpublished studies and abstracts from conference proceedings were also reviewed. Studies involving adult patients with CUP who underwent both MTP and clinical evaluation with IHC were identified. Articles were included if they had primary data sufficient to calculate both sensitivity and specificity. Methodological qualities of the included studies were evaluated using the QUADAS-2 tool. Data was analyzed using Review Manager 5.3 and MetaDiSc 1.4. Results: Seven studies with 549 patients were analyzed. MTP was found to have a pooled sensitivity of 89% (95% CI 0.85-0.92)and pooled specificity of 74% (95% CI 0.67-0.80)with pooled positive and negative likelihood ratios of 2.97 (95% CI 1.17-7.63) and 0.20 (95% CI 0.07-0.51), respectively. Area under the curve was measured to be 0.9107. Conclusions: This meta-analysis suggests that MTP could be useful in determining the tissue of origin in adult patients with CUP. With an area under the curve of 0.9107, it is an excellent diagnostic test. The results showed considerable heterogeneity as expected in meta-analyses of diagnostic test accuracy. In this case, it may be due to variability among the MTP assays used which may reflect different cutoffs.

A Meta-Analysis of Diagnostic Test Accuracy (DTA) of the Endoscopic Ultrasound (EUS) and Magnetic Resonance Cholangiopancreatography (MRCP) in Detecting Choledocholithiasis

Introduction: Published reports provide a wide range of sensitivity and specificity for EUS and MRCP in the diagnosis of the choledocholithiasis. However, a proper meta-analysis of DTA is lacking. Here, we aimed at determining and comparing the diagnostic accuracy of EUS and MRCP in detecting choledocholithiasis using appropriate methodology recommended by the Cochrane group. Methods: A comprehensive electronic literature search up to March 2016 was done by two reviewers for prospective cohort studies comparing EUS and MRCP to the gold standard in detecting choledocholithiasis. The gold standard was considered endoscopic retrograde cholangiopancreatography (ERCP), intra-operative cholangiography (IOC) or clinical follow up >3 months for negative cases. There was no restriction in terms of language, location or quality sof the studies. Abstracts, unpublished data, studies with insufficient data and pediatric studies were excluded. Quality of the included studies was measured using QUADAS-2 tool. Data analysis was done using DerSimonian Laird method (random effects model) on intention-to-treat data. Mantel-Haenszel or the DerSimonian Laird methods to estimate the overall diagnostic Odds Ratio (DOR) and hence to determine the best-fitting receiver operating characteristics (ROC) curve. Symmetrical ROC (sROC) was developed and area under curve (AUC) was calculated. Results: A total of five out of fourteen studies were included. Three studies were from Europe, one from Japan and one from the US. All studies had low risk of bias. The pooled sensitivity, specificity, DOR and AUC for EUS were 96.6(91.4-99.1)%, 89.7(83.3-94.3)%, 0.9771, 162.5(54.0-489.3), and 0.977 (SE:0.011,Q:0.932), respectively. The pooled sensitivity, specificity, DOR and AUC for MRCP were 87.1(79.6-92.6)%, 92.5(86.9-96.2)%, 79.0(23.8-262.2) and 0.95.2 (SE:0.027; Q:0.89), respectively. The difference between the AUC of diagnostic accuracy of EUS and MRCP was 0.0248 (SE:0.015) arithmetically in favor of EUS but it was not significantly different (p:0.10, two-tailed). Conclusion: Both EUS and MRCP provide very good diagnostic accuracy in detecting choledocholithiasis with slight arithmetical superiority with EUS. Individual participant data and meta-regression analyses may identify the characters that may benefit from one modality or the other.Figure 1Figure 2

A simple and robust method for multivariate meta-analysis of diagnostic test accuracy.

Meta-analysis of diagnostic test accuracy often involves mixture of case-control and cohort studies. The existing bivariate random-effects models, which jointly model bivariate accuracy indices (e.g., sensitivity and specificity), do not differentiate cohort studies from case-control studies and thus do not utilize the prevalence information contained in the cohort studies. The recently proposed trivariate generalized linear mixed-effects models are only applicable to cohort studies, and more importantly, they assume a common correlation structure across studies and trivariate normality on disease prevalence, test sensitivity, and specificity after transformation by some pre-specified link functions. In practice, very few studies provide justifications of these assumptions, and sometimes these assumptions are violated. In this paper, we evaluate the performance of the commonly used random-effects model under violations of these assumptions and propose a simple and robust method to fully utilize the information contained in case-control and cohort studies. The proposed method avoids making the aforementioned assumptions and can provide valid joint inferences for any functions of overall summary measures of diagnostic accuracy. Through simulation studies, we find that the proposed method is more robust to model misspecifications than the existing methods. We apply the proposed method to a meta-analysis of diagnostic test accuracy for the detection of recurrent ovarian carcinoma. Copyright © 2016 John Wiley & Sons, Ltd.

Modelling multiple thresholds in meta-analysis of diagnostic test accuracy studies.

BackgroundIn meta-analyses of diagnostic test accuracy, routinely only one pair of sensitivity and specificity per study is used. However, for tests based on a biomarker or a questionnaire often more than one threshold and the corresponding values of true positives, true negatives, false positives and false negatives are known.MethodsWe present a new meta-analysis approach using this additional information. It is based on the idea of estimating the distribution functions of the underlying biomarker or questionnaire within the non-diseased and diseased individuals. Assuming a normal or logistic distribution, we estimate the distribution parameters in both groups applying a linear mixed effects model to the transformed data. The model accounts for across-study heterogeneity and dependence of sensitivity and specificity. In addition, a simulation study is presented.ResultsWe obtain a summary receiver operating characteristic (SROC) curve as well as the pooled sensitivity and specificity at every specific threshold. Furthermore, the determination of an optimal threshold across studies is possible through maximization of the Youden index. We demonstrate our approach using two meta-analyses of B type natriuretic peptide in heart failure and procalcitonin as a marker for sepsis.ConclusionsOur approach uses all the available information and results in an estimation not only of the performance of the biomarker but also of the threshold at which the optimal performance can be expected.Electronic supplementary materialThe online version of this article (doi:10.1186/s12874-016-0196-1) contains supplementary material, which is available to authorized users.

The Moses–Littenberg meta-analytical method generates systematic differences in test accuracy compared to hierarchical meta-analytical models

ObjectiveTo compare meta-analyses of diagnostic test accuracy using the Moses–Littenberg summary receiver operating characteristic (SROC) approach with those of the hierarchical SROC (HSROC) model. Study Design and SettingTwenty-six data sets from existing test accuracy systematic reviews were reanalyzed with the Moses–Littenberg model, using equal weighting (“E-ML”) and weighting by the inverse variance of the log DOR (“W-ML”), and with the HSROC model. The diagnostic odds ratios (DORs) were estimated and covariates added to both models to estimate relative DORs (RDORs) between subgroups. Models were compared by calculating the ratio of DORs, the ratio of RDORs, and P-values for detecting asymmetry and effects of covariates on DOR. ResultsCompared to the HSROC model, the Moses–Littenberg model DOR estimates were a median of 22% (“E-ML”) and 47% (“W-ML”) lower at Q*, and 7% and 42% lower at the central point in the data. Instances of the ML models giving estimates higher than the HSROC model also occurred. Investigations of heterogeneity also differed; the Moses–Littenberg models on average estimating smaller differences in RDOR. ConclusionsMoses–Littenberg meta-analyses can generate lower estimates of test accuracy, and smaller differences in accuracy, compared to mathematically superior hierarchical models. This has implications for the usefulness of meta-analyses using this approach. We recommend meta-analysis of diagnostic test accuracy studies to be conducted using available hierarchical model–based approaches.

A general framework for the use of logistic regression models in meta-analysis.

Where individual participant data are available for every randomised trial in a meta-analysis of dichotomous event outcomes, "one-stage" random-effects logistic regression models have been proposed as a way to analyse these data. Such models can also be used even when individual participant data are not available and we have only summary contingency table data. One benefit of this one-stage regression model over conventional meta-analysis methods is that it maximises the correct binomial likelihood for the data and so does not require the common assumption that effect estimates are normally distributed. A second benefit of using this model is that it may be applied, with only minor modification, in a range of meta-analytic scenarios, including meta-regression, network meta-analyses and meta-analyses of diagnostic test accuracy. This single model can potentially replace the variety of often complex methods used in these areas. This paper considers, with a range of meta-analysis examples, how random-effects logistic regression models may be used in a number of different types of meta-analyses. This one-stage approach is compared with widely used meta-analysis methods including Bayesian network meta-analysis and the bivariate and hierarchical summary receiver operating characteristic (ROC) models for meta-analyses of diagnostic test accuracy.

Diagnostic Accuracy of PIK3CA Mutation Detection by Circulating Free DNA in Breast Cancer: A Meta-Analysis of Diagnostic Test Accuracy.

Mutation of p110 alpha-catalytic subunit of phosphatidylinositol 3-kinase (PIK3CA) has high predictive and prognostic values for breast cancer. Hence, there has been a marked interest in detecting and monitoring PIK3CA genotype with non-invasive technique, such as circulating free DNA (cfDNA). However, the diagnostic accuracy of PIK3CA genotyping by cfDNA is still a problem of controversy. Here, we conducted the first meta-analysis to evaluate overall diagnostic performance of cfDNA for PIK3CA mutation detection. Literature search was performed in Pubmed, Embase and Cochrane Central Register of Controlled Trials databases. Seven cohorts from five studies with 247 patients were included. The pooled sensitivity, specificity, positive and negative likelihood ratio, diagnostic odds ratio and area under summary receiver operating characteristic curve were calculated for accuracy evaluation. The pooled sensitivity and specificity were 0.86 (95% confidence interval [CI] 0.32–0.99) and 0.98 (95% CI 0.86–1.00), respectively; the pooled positive and negative likelihood ratio were 42.8 (95% CI 5.1–356.9) and 0.14 (95% CI 0.02–1.34), respectively; diagnostic odds ratio for evaluating the overall diagnostic performance was 300 (95% CI 8–11867); area under summary receiver operating characteristic curve reached 0.99 (95% CI 0.97–0.99). Subgroup analysis with metastatic breast cancer revealed remarkable improvement in diagnostic performance (sensitivity: 0.86–0.91; specificity: 0.98; diagnostic odds ratio: 300–428). This meta-analysis proved that detecting PIK3CA gene mutation by cfDNA has high diagnostic accuracy in breast cancer, especially for metastatic breast cancer. It may serve as a reliable non-invasive assay for detecting and monitoring PIK3CA mutation status in order to deliver personalized and precise treatment.

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

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

Thiopurine S-methyltransferase testing for averting drug toxicity: a meta-analysis of diagnostic test accuracy.

Thiopurine S-methyltransferase (TPMT) deficiency increases the risk of serious adverse events in persons receiving thiopurines. The objective was to synthesize reported sensitivity and specificity of TPMT phenotyping and genotyping using a latent class hierarchical summary receiver operating characteristic meta-analysis. In 27 studies, pooled sensitivity and specificity of phenotyping for deficient individuals was 75.9% (95% credible interval (CrI), 58.3-87.0%) and 98.9% (96.3-100%), respectively. For genotype tests evaluating TPMT*2 and TPMT*3, sensitivity and specificity was 90.4% (79.1-99.4%) and 100.0% (99.9-100%), respectively. For individuals with deficient or intermediate activity, phenotype sensitivity and specificity was 91.3% (86.4-95.5%) and 92.6% (86.5-96.6%), respectively. For genotype tests evaluating TPMT*2 and TPMT*3, sensitivity and specificity was 88.9% (81.6-97.5%) and 99.2% (98.4-99.9%), respectively. Genotyping has higher sensitivity as long as TPMT*2 and TPMT*3 are tested. Both approaches display high specificity. Latent class meta-analysis is a useful method for synthesizing diagnostic test performance data for clinical practice guidelines.The Pharmacogenomics Journal advance online publication, 24 May 2016; doi:10.1038/tpj.2016.37.

Diagnostic Accuracy of Transcranial Doppler for Brain Death Confirmation: Systematic Review and Meta-Analysis.

Transcranial Doppler is a useful ancillary test for brain death confirmation because it is safe, noninvasive, and done at the bedside. Transcranial Doppler confirms brain death by evaluating cerebral circulatory arrest. Case series studies have generally reported good correlations between transcranial Doppler confirmation of cerebral circulatory arrest and clinical confirmation of brain death. The purpose of this study is to evaluate the utility of transcranial Doppler as an ancillary test in brain death confirmation. We conducted a systematic review of the literature and a diagnostic test accuracy meta-analysis to compare the sensitivity and specificity of transcranial Doppler confirmation of cerebral circulatory arrest, by using clinical confirmation of brain death as the criterion standard. We identified 22 eligible studies (1671 patients total), dating from 1987 to 2014. Pooled sensitivity and specificity estimates from 12 study protocols that reported data for the calculation of both values were 0.90 (95% CI, 0.87-0.92) and 0.98 (95% CI, 0.96-0.99), respectively. Between-study differences in the diagnostic performance of transcranial Doppler were found for both sensitivity (I(2) = 76%; P < .001) and specificity (I(2) = 74.3%; P < .001). The threshold effect was not significant (Spearman r = -0.173; P = .612). The area under the curve with the corresponding standard error (SE) was 0.964 ± 0.018, while index Q test ± SE was estimated at 0.910 ± 0.028. The results of this meta-analysis suggest that transcranial Doppler is a highly accurate ancillary test for brain death confirmation. However, transcranial Doppler evaluates cerebral circulatory arrest rather than brain stem function, and this limitation needs to be taken into account when interpreting the results of this meta-analysis.

A general framework for comparative Bayesian meta-analysis of diagnostic studies.

BackgroundSelecting the most effective diagnostic method is essential for patient management and public health interventions. This requires evidence of the relative performance of alternative tests or diagnostic algorithms. Consequently, there is a need for diagnostic test accuracy meta-analyses allowing the comparison of the accuracy of two or more competing tests. The meta-analyses are however complicated by the paucity of studies that directly compare the performance of diagnostic tests. A second complication is that the diagnostic accuracy of the tests is usually determined through the comparison of the index test results with those of a reference standard. These reference standards are presumed to be perfect, i.e. allowing the classification of diseased and non-diseased subjects without error. In practice, this assumption is however rarely valid and most reference standards show false positive or false negative results. When an imperfect reference standard is used, the estimated accuracy of the tests of interest may be biased, as well as the comparisons between these tests.MethodsWe propose a model that allows for the comparison of the accuracy of two diagnostic tests using direct (head-to-head) comparisons as well as indirect comparisons through a third test. In addition, the model allows and corrects for imperfect reference tests. The model is inspired by mixed-treatment comparison meta-analyses that have been developed for the meta-analysis of randomized controlled trials. As the model is estimated using Bayesian methods, it can incorporate prior knowledge on the diagnostic accuracy of the reference tests used.ResultsWe show the bias that can result from using inappropriate methods in the meta-analysis of diagnostic tests and how our method provides more correct estimates of the difference in diagnostic accuracy between two tests. As an illustration, we apply this model to a dataset on visceral leishmaniasis diagnostic tests, comparing the accuracy of the RK39 dipstick with that of the direct agglutination test.ConclusionsOur proposed meta-analytic model can improve the comparison of the diagnostic accuracy of competing tests in a systematic review. This is however only true if the studies and especially information on the reference tests used are sufficiently detailed. More specifically, the type and exact procedures used as reference tests are needed, including any cut-offs used and the number of subjects excluded from full reference test assessment. If this information is lacking, it may be better to limit the meta-analysis to direct comparisons.Electronic supplementary materialThe online version of this article (doi:10.1186/s12874-015-0061-7) contains supplementary material, which is available to authorized users.

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

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...

Performance of methods for meta-analysis of diagnostic test accuracy with few studies or sparse data.

Hierarchical models such as the bivariate and hierarchical summary receiver operating characteristic (HSROC) models are recommended for meta-analysis of test accuracy studies. These models are challenging to fit when there are few studies and/or sparse data (for example zero cells in contingency tables due to studies reporting 100% sensitivity or specificity); the models may not converge, or give unreliable parameter estimates. Using simulation, we investigated the performance of seven hierarchical models incorporating increasing simplifications in scenarios designed to replicate realistic situations for meta-analysis of test accuracy studies. Performance of the models was assessed in terms of estimability (percentage of meta-analyses that successfully converged and percentage where the between study correlation was estimable), bias, mean square error and coverage of the 95% confidence intervals. Our results indicate that simpler hierarchical models are valid in situations with few studies or sparse data. For synthesis of sensitivity and specificity, univariate random effects logistic regression models are appropriate when a bivariate model cannot be fitted. Alternatively, an HSROC model that assumes a symmetric SROC curve (by excluding the shape parameter) can be used if the HSROC model is the chosen meta-analytic approach. In the absence of heterogeneity, fixed effect equivalent of the models can be applied.

Narrow-band imaging bronchoscopy in the detection of premalignant airway lesions: a meta-analysis of diagnostic test accuracy.

Both autofluorescence imaging bronchoscopy and narrow-band imaging have shown promise in the detection of premalignant airway lesions, each by utilizing different bandwidths of lights for better characterization of the mucosal and submucosal vascular grid. Since previously published meta-analyses have shown poor specificity of autofluorescence imaging bronchoscopy, we specifically studied the diagnostic accuracy of narrow-band imaging alone and in combination with autofluorescence imaging bronchoscopy in the detection of premalignant airway lesions. After an extensive search of eligible studies from PubMed and Medline, extracted data were pooled with weighted averages. Symmetrical summary-receiver operating characteristic curves were constructed to summarize the results quantitatively. Study heterogeneity was assessed by the I(2) index. Analysis of data from eight studies on narrow-band imaging showed a pooled sensitivity of 0.80 [95% confidence interval (CI): 0.77-0.83] and a pooled specificity of 0.84 (95% CI: 0.81-0.86). Summary-receiver operating characteristic curves from the data on narrow-band imaging calculated an area-under-the-curve of 0.908 (standard error 0.01). The diagnostic odds ratio of narrow-band imaging was 31.49 (95% CI: 12.17-81.45). Data from studies where narrow-band imaging and autofluorescence imaging bronchoscopy were used together showed a pooled sensitivity, specificity, area-under-the-curve and diagnostic odds ratios of 0.86 (95% CI: 0.82-0.89), 0.75 (95% CI: 0.71-0.79), 0.964 (standard error 0.05) and 27.96 (95% CI: 3.04-257.21), respectively. Our findings indicate that in the evaluation of premalignant airway lesions, narrow-band imaging has a higher sensitivity, specificity and diagnostic odds ratios compared with autofluorescence imaging bronchoscopy. However, combining autofluorescence imaging bronchoscopy and narrow-band imaging does not significantly improve test performance characteristics.

Small-study effects and time trends in diagnostic test accuracy meta-analyses: a meta-epidemiological study.

BackgroundSmall-study effects and time trends have been identified in meta-analyses of randomized trials. We evaluated whether these effects are also present in meta-analyses of diagnostic test accuracy studies.MethodsA systematic search identified test accuracy meta-analyses published between May and September 2012. In each meta-analysis, the strength of the associations between estimated accuracy of the test (diagnostic odds ratio (DOR), sensitivity, and specificity) and sample size and between accuracy estimates and time since first publication were evaluated using meta-regression models. The regression coefficients over all meta-analyses were summarized using random effects meta-analysis.ResultsForty-six meta-analyses and their corresponding primary studies (N = 859) were included. There was a non-significant relative change in the DOR of 1.01 per 100 additional participants (95% CI 1.00 to 1.03; P = 0.07). In the subgroup of imaging studies, there was a relative increase in sensitivity of 1.13 per 100 additional diseased subjects (95% CI 1.05 to 1.22; P = 0.002). The relative change in DOR with time since first publication was 0.94 per 5 years (95% CI 0.80 to 1.10; P = 0.42). Sensitivity was lower in studies published later (relative change 0.89, 95% CI 0.80 to 0.99; P = 0.04).ConclusionsSmall-study effects and time trends do not seem to be as pronounced in meta-analyses of test accuracy studies as they are in meta-analyses of randomized trials. Small-study effects seem to be reversed in imaging, where larger studies tend to report higher sensitivity.Electronic supplementary materialThe online version of this article (doi:10.1186/s13643-015-0049-8) contains supplementary material, which is available to authorized users.

OP-184 The Role of Optical Coherence Tomography in Prediction of Coronary Ischemia Assessed by Fractional Flow Reserve: Meta-analysis of Diagnostic Test Accuracy

A and 0.364 accordingly). Pre-exercise, peak-exercise and postexercise BNP and troponin I values were similar across the groups (p>0.05 for all comparisons). Serum copeptin values for preexercise and peak-exercise were similar among all groups (p1⁄40.883 and 0.089). Postexercise copeptin value of the normal and equivocal groups were similar (p1⁄40.661 z1⁄4-0.438) while that of the ischemia group was significantly higher than both normal group (p<0.001 z1⁄4-4.612) and equivocal group (p<0.001 z1⁄4-4.440). Conclusions: Serum copeptin was found to be increasing significantly in case of ischemia on MPS. It may be used in differentitaion of equivocal results from false positive results. B S -OP-183

Diagnostic accuracy of single baseline measurement of Elecsys Troponin T high-sensitive assay for diagnosis of acute myocardial infarction in emergency department: systematic review and meta-analysis

Objective To obtain summary estimates of the accuracy of a single baseline measurement of the Elecsys Troponin T high-sensitive assay (Roche Diagnostics) for the diagnosis of acute myocardial infarction in...