Evaluating the effectiveness of child and adolescent group treatment: a meta-analytic review.

Utilizing 56 outcome studies published between 1974 and 1997, this meta-analysis specifically examines the effect of group treatment with children and adolescents (ages 4-18). Various types of group treatment were assessed, including preventative programs, psychotherapy, counseling, guidance, and training groups. Results indicate that group treatment was significantly more effective for children than wait-list and placebo control groups (effect size = .61). That is, the average child or adolescent treated by group treatment is better off than 73% of those in control groups. This meta-analysis strengthens and supports conclusions in the current literature and challenges others regarding the treatment of children and adolescents by group treatment. For instance, allegiance of the experimenter, setting of the therapy, socioeconomic status of the patient, and publication year of the study were variables that were significantly related to improvement, whereas diagnosis, content and source of the outcome measure were unrelated to improvement.