Moving from evidence to action

Abstract

Decision making should always be based on the best evidence while also taking into account stakeholder values and resources. The traditional hierarchy of evidence puts at the uppermost level a large randomized trial or a meta-analysis of homogeneous randomized trials. This approach is atomically correct but fails to capture the complexity and comprehensiveness of evidence sources. Umbrella reviews, overviews of reviews, and meta-epidemiologic studies offer a novel tool to summarize and appraise clinical evidence at a level which is even more general than that of meta-analyses. Knowledge is an essential prerequisite of effective action, but if such exercises in evidence synthesis are to be truly meaningful, their impact on decision making must actually translate into specifi c actions. To enable this, while empowering all stakeholders, it is crucial to search appropriately for umbrella reviews, to correctly appraise them, and to correctly grade them in terms of pragmatic impact.