Comprehensive overview of methods and reporting of meta-analyses of test accuracy

Article type
Authors
Dahabreh IJ1, Chung M1, Kitsios GD1, Terasawa T2, Raman G1, Tatsioni A3, Tobar A4, Lau J1, Trikalinos TA5, Schmid CH6
1Center for Clinical Evidence Synthesis, Institute for Clinical Research and Health Policy Studies, Tufts Medical Center, Boston, MA
2Department of Internal Medicine, Fujita Health University Nanakuri Sanatorium, Fujita Health University School of Medicine, Tsu, Mie, Japan
3Department of Internal Medicine, University of Ioannina School of Medicine, Ioannina, Greece
4Division of Gastroenterology & Hepatology, Department of Medicine, University of Colorado, Aurora, CO
5Center for Evidence-based Medicine, Program in Public Health, Brown University, Providence, RI
6Biostatistics Research Center, Institute for Clinical Research and Health Policy Studies, Tufts Medical Center, Boston, MA
Abstract
Background: Meta-analyses of test accuracy are increasingly performed and methods are continually evolving.

Objectives: To survey the methods and reporting practices in meta-analyses of test accuracy.

Methods: We searched MEDLINE (1966–2009), reference lists and relevant reviews for meta-analyses of test accuracy for diagnostic or predictive medical tests. Nine reviewers extracted information on clinical topics, literature review methods, quality assessment and statistical analyses performed.

Results: We reviewed 760 meta-analyses of test accuracy, published 1987–2009. Eligible reviews averaged 18 primary studies and typically examined one index test against one reference standard. Most common clinical areas were cardiovascular disease (21%) and oncology (25%); most common test categories were imaging (44%) and biomarker tests (28%). 62% used at least two electronic databases to identify eligible studies; the number has increased over time. Assessment of verification bias, spectrum bias, blinding, prospective study design, and consecutive patient recruitment also became significantly more common over time (P < 0.001, comparing reviews published through 2004 vs. 2005 onwards). Improvements coincided with increasing use of quality-item checklists to guide assessment of methodological quality. Sensitivity (77%), specificity (74%) and odds ratios (34%) were the most commonly used metrics. Heterogeneity tests were used in 58% of meta-analyses and subgroup or regression analyses were used in 57%. Random effects models were employed in 57% of meta-analyses and increasingly over time (38% through 2004 vs. 72% 2004-onwards; P < 0.001). Use of bivariate models of sensitivity and specificity also increased in recent years (21% of reviews published in 2008–2009 vs. 5% in earlier years; P < 0.001).

Conclusions: Methods employed in meta-analyses of test accuracy have improved with the introduction of quality assessment checklists and the development of more sophisticated statistical methods. However, multivariate methods for meta-analysis and reporting of study design characteristics are still lacking in a substantial number of diagnostic test meta-analyses.