Capture-mark-recapture to estimate the number of missed articles for systematic reviews in surgery

BACKGROUND: Systematic reviews are an important knowledge synthesis tool, but with new literature available each day, reviewers must balance identifying all relevant literature against timely synthesis. METHODS: This study tested capture-mark-recapture (CMR), an ecology-based technique, to estimate the total number of articles in the literature identified in a systematic review of adult trauma care quality indicators. RESULTS: The systematic review included 40 articles identified from online searches and citation references. The CMR model suggested that 3 (95% confidence interval [CI]: 0 to 6) articles were missed and the database search provided 93% (one-sided 95% CI: ≥83%) of known articles for inclusion in the systematic review. The search order used for identifying the articles was optimal among the 24 that could have been used. CONCLUSIONS: The CMR technique can be used in systematic reviews in surgery to estimate the closeness to capturing the total body of literature for a specific topic.