Meta-Analysis in Criminal Justice and Criminology: What It is, When It's Useful, and What to Watch Out for

Meta-analyses are becoming more common in the criminal justice and criminological literature. While much of the published work related to the technique is focused on the more technical aspects of the statistical methods that have been developed for meta-analysis, less common are broader-and perhaps more critical-discussions concerning various issues associated with the method. Accordingly, this article presents an overview of meta-analysis in the context of what have become three of the more important issues within the meta-analysis literature in recent years: (1) the conditions under which meta-analyses are, and are not, most useful, (2) the dilemma of whether or not to include unpublished work in the sample of studies to be analyzed, and (3) the choice of bivariate versus multivariate effect size estimates to be synthesized. The objective is to take these issues out of what has arguably been debates about technical orthodoxy and instead to place them into a broader research context within criminal justice and criminology.