Evaluating effects of residential treatment for juvenile offenders by statistical metaanalysis: A review

Statistical metaanalyses on the effects of residential treatment for juvenile offenders were reviewed to examine the mean effect sizes and reductions of recidivism reported for this group. Five metaanalyses (three on North American and two on European studies) were selected and synthesized in a second-order narrative review. All metaanalyses reported positive mean effect sizes, with d statistics varying from 0.09 to 0.31, and an average reduction of recidivism by about 9%. The review showed that the "nothing works" hypothesis, concerning treatment effects for juvenile offenders, could be replaced by moderate optimism. However, metaanalysts need to be aware of the contextual embeddedness of treatment programs and the heterogeneity of studies included. Future research syntheses should focus on European contexts and multiple measures to evaluate long-term effects. (C) 2003 Elsevier Ltd. All rights reserved