Standards for evidence and evidence for standards: The case of school-based drug prevention

The Campbell Collaboration Crime and justice Group continues to focus on issues of evidence: what studies count in a systematic review and how many studies are needed to claim an intervention works. They are not alone. Since the mid-1990s, a number of similar efforts have sprung up to provide guidance to policy makers who wish to adopt programs to prevent violence or drug use. Many of these are particularly relevant to school-based drug prevention programs. This article describes seven efforts to produce guides to research-based programs, focusing on the standards adopted to determine what evidence counts and how much of it is necessary to determine that it worked. The author concludes with a discussion of some of the issues raised by this review.