Meta-analysis protocol registration: sed quis custodiet ipsos custodes? (but who will guard the guardians?).

摘要

A tidal wave of guidelines is flooding the epidemiologic world. Many have in common the requirement that research protocols should be registered when still in an embryonic phase. Having hit the world of clinical trials, this wave of requirements has reached observational studies, and, most recently, meta-analyses. The PRISMA (Preferred Reporting Items Systematic Reviews and Meta-Analysis) guidelines demand the prior registration of the protocol of any systematic review and meta-analysis, requiring that this protocol should be made accessible before any hands-on work is done.1 Such registration is claimed to be similar in rationale to the registration of clinical trials. It will "reduce the risk of an excessive number of reviews addressing the same question" and allow tracking of any subgroup analysis that has been carried out without prespecification in the protocol.