title: An empirical comparison of methods for meta-analysis of diagnostic accuracy showed hierarchical models are necessary.
abstract: OBJECTIVE
  Meta-analysis of studies of the accuracy of diagnostic tests currently uses a variety of methods. Statistically rigorous hierarchical models require expertise and sophisticated software. We assessed whether any of the simpler methods can in practice give adequately accurate and reliable results.
  
  
  METHODS
  We reviewed six methods for meta-analysis of diagnostic accuracy: four simple commonly used methods (simple pooling, separate random-effects meta-analyses of sensitivity and specificity, separate meta-analyses of positive and negative likelihood ratios, and the Littenberg-Moses summary receiver operating characteristic [ROC] curve) and two more statistically rigorous approaches using hierarchical models (bivariate random-effects meta-analysis and hierarchical summary ROC curve analysis). We applied the methods to data from a sample of eight systematic reviews chosen to illustrate a variety of patterns of results.
  
  
  RESULTS
  In each meta-analysis, there was substantial heterogeneity between the results of different studies. Simple pooling of results gave misleading summary estimates of sensitivity and specificity in some meta-analyses, and the Littenberg-Moses method produced summary ROC curves that diverged from those produced by more rigorous methods in some situations.
  
  
  CONCLUSIONS
  The closely related hierarchical summary ROC curve or bivariate models should be used as the standard method for meta-analysis of diagnostic accuracy.
authors.affiliation: MRC Health Services Research Collaboration, Department of Social Medicine, University of Bristol, Bristol, UK. roger.harbord@bristol.ac.uk
authors.forename: Roger M
authors.initials: RM
authors.lastname: Harbord
authors.forename: Penny
authors.initials: P
authors.lastname: Whiting
authors.forename: Jonathan A C
authors.initials: JA
authors.lastname: Sterne
authors.forename: Matthias
authors.initials: M
authors.lastname: Egger
authors.forename: Jonathan J
authors.initials: JJ
authors.lastname: Deeks
authors.forename: Aijing
authors.initials: A
authors.lastname: Shang
authors.forename: Lucas M
authors.initials: LM
authors.lastname: Bachmann
mesh_terms: D003627:Data Interpretation, Statistical; D003955:Diagnostic Tests, Routine / Q000592:standards*; D006801:Humans; D015201:Meta-Analysis as Topic; D015233:Models, Statistical; D012372:ROC Curve; D012196:Review Literature as Topic