| This meta-analytic review explored the effect of group-based psychotherapy in the school environment on the psychological functioning and treatment outcomes of children and adolescents. Meta-analytic techniques were used to determine how group-based treatment outcomes compare to the outcomes of control and/or alternative treatment conditions, how group therapy treatment groups compare at pre-treatment and post-treatment assessments of outcome, and which therapist, client, treatment, and methodological variables are associated with the overall efficacy of group therapy with children and adolescents in the school environment. The study included 98 articles from 1997 to 2012 which were coded for descriptive variables, and 87 of these studies reported data that was used to calculation effect sizes and perform subsequent analyses. A medium to large winsorized overall within group treatment effect size (M= 0.67, SD = 0.65) was found in the present review, suggesting that school-based group therapy is effective in meeting the mental health needs of children and adolescents. A medium winsorized overall between group effect size comparing group treatment conditions to control conditions (M= 0.51, SD= 0.59) was also found, and a small effect size (M= 0.32, SD = 0.46) was found for studies comparing group treatment conditions to alternative treatment conditions. Additionally, the variables of treatment modality, study quality, and treatment group homogeneity were found to be significantly related to treatment efficacy. Further implications and limitations of the results of this meta-analysis are discussed, as they relate to the training and practice of school psychologists and related educational professionals. |
