Empirical evaluation suggests Copas selection model preferable to trim-and-fill method for selection bias in meta-analysis

Meta-analysis yields a biased result if published studies represent a biased selection of the evidence. Copas proposed a selection model to assess the sensitivity of meta-analysis conclusions to possible selection bias. An alternative proposal is the trim-and-fill method. This article reports an empirical comparison of the two methods.We took 157 meta-analyses with binary outcomes, analyzed each one using both methods, then performed an...