An international registry of systematic-review protocols

Support for prospective registration of protocols for systematic reviews has been gathering momentum.1-3 The PRISMA statement, a guideline for reporting systematic reviews and meta-analyses of studies that evaluate health-care interventions, advocates registration.1,2 Well-conducted systematic reviews are accepted as the best-quality evidence to inform policy and practice, and the dramatic upward trend in the number of systematic reviews published annually (figure) is set to continue.3 However, there is currently no single facility for identifying this type of research in advance of the appearance of the results of the review. In both the prevention and revelation of potential bias, registration should improve quality and increase confidence that policy or practice informed by the findings of systematic reviews are indeed drawing on best-quality evidence.