Long-term effects of prevention and treatment on youth antisocial behavior: A meta-analysis.

Youth antisocial behavior exacts a tremendous toll on society and often persists into adulthood. Although researchers have identified a number of psychosocial interventions that prevent or reduce youth antisocial behavior in the short term, evidence of long-term intervention benefits has only recently become available. In addition, research on such interventions spans two substantial but largely separate bodies of literature: prevention and therapy. The present study used meta-analysis to integrate research on the long-term effects of preventive and therapeutic interventions for youth antisocial behavior and examined potential moderators of these effects. Results from 66 intervention trials (i.e., 34 prevention, 32 therapy) indicated that a broad range of youth psychosocial interventions demonstrated modest effects on antisocial behavior (mean d=0.31, 95% confidence interval=0.23-0.39) for at least one year beyond the end of interventions relative to control conditions. Among other findings, moderator analyses revealed that inclusion of a peer group intervention component was associated with reduced intervention effects for samples consisting predominantly of boys or older youths. The results of this study have important implications for service providers, administrators, and policymakers involved in the implementation of preventive and therapeutic interventions targeting youth antisocial behavior.