A large-scale meta-analysis relating the hare measures of psychopathy to antisocial conduct.

The present meta-analysis integrated effect sizes from 95 non-overlapping studies (N=15,826) to summarize the relation between Hare Psychopathy Checklists and antisocial conduct. Whereas prior meta-analyses focused on specific subdomains of the literature, we used broad inclusion criteria, incorporating a diversity of samples, settings, methodologies, and outcomes in our analysis. Our broad perspective allowed us to identify general trends consistent across the entire literature and improved the power of our analyses. Results indicated that higher PCL Total, Factor 1 (F(1)), and Factor 2 (F(2)) scores were moderately associated with increased antisocial conduct. Study effect sizes were significantly moderated by the country in which the study was conducted, racial composition, gender composition, institutional setting, the type of information used to score psychopathy, and the independence of psychopathy and transgression assessments. However, multiple regression analyses indicated that the information used to assess psychopathy did not have a unique influence on effect sizes after accounting for the influence of other moderator variables. Furthermore, racial composition of the sample was related to the country in which the study was conducted, making it unclear whether one or both of these moderators influenced effect sizes. We provide potential explanations for the significant findings and discuss implications of the results for future research.