Objectives

To conduct a meta-analytic review of selective and indicated mentoring interventions for effects for youth at risk on delinquency and key associated outcomes (aggression, drug use, academic functioning). We also undertook the first systematic evaluation of intervention implementation features and organization and tested for effects of theorized key processes of mentor program effects.

Methods

Campbell Collaboration review inclusion criteria and procedures were used to search and evaluate the literature. Criteria included a sample defined as at risk for delinquency due to individual behavior such as aggression or conduct problems or environmental characteristics such as residence in a high-crime community. Studies were required to be random assignment or strong quasi-experimental design. Of 163 identified studies published from 1970–2011, 46 met criteria for inclusion.

Results

Mean effects sizes were significant and positive for each outcome category (ranging from d = 0.11 for academic achievement to d = 0.29 for aggression). Heterogeneity in effect sizes was noted for all four outcomes. Stronger effects resulted when mentor motivation was professional development but not by other implementation features. Significant improvements in effects were found when advocacy and emotional support mentoring processes were emphasized.

Conclusions

This popular approach has significant impact on delinquency and associated outcomes for youth at risk for delinquency. While evidencing some features may relate to effects, the body of literature is remarkably lacking in details about specific program features and procedures. This persistent state of limited reporting seriously impedes understanding about how mentoring is beneficial and ability to maximize its utility.