Identification of application and interpretation errors that can occur in pairwise meta-analyses in systematic reviews of interventions: A systematic review

Objective To generate a bank of items describing application and interpretation errors that can arise in pairwise meta-analyses in systematic reviews of interventions. Study design and setting Medline, Embase and Scopus were searched to identify studies describing types of errors in meta-analyses. Descriptions of errors and supporting quotes were extracted by multiple authors. Errors were reviewed at team meetings to determine if they should be excluded, reworded, or combined with other errors, and were categorised into broad categories of errors and subcategories within. Results 50 articles met our inclusion criteria, leading to the identification of 139 errors. We identified 25 errors covering data extraction/manipulation, 74 covering statistical analyses, and 40 covering interpretation. Many of the statistical analysis errors related to the meta-analysis model (e.g. using a two-stage strategy to determine whether to select a fixed or random-effects model) and statistical heterogeneity (e.g. not undertaking an assessment for statistical heterogeneity). Conclusions We generated a comprehensive bank of possible errors that can arise in the application and interpretation of meta-analyses in systematic reviews of interventions. This item bank of errors provides the foundation for developing a checklist to help peer reviewers detect statistical errors.