Using a Cross-Study Design to Assess the Efficacy of Motivational Enhancement Therapy–Cognitive Behavioral Therapy 5 (MET/CBT5) in Treating Adolescents with Cannabis-Related Disorders

Abstract

To evaluate how adolescents with marijuana problems who received a research-based treatment (five sessions of motivational enhancement therapy plus cognitive behavioral therapy [MET/CBT5]) in an experimental setting would have fared had they received exemplary community-based outpatient treatment. Twelve-month outcomes representing six domains (substance use problems, substance use frequency, emotional problems, illegal activities, recovery, and institutionalization) were assessed for youth who received MET/CBT5 in the Cannabis Youth Treatment study and youth who received outpatient treatment from one of three community-based programs selected for evidence of efficacy. Groups were matched on pretreatment characteristics using a propensity score weighting strategy. Youth who received MET/CBT5 exhibited greater reductions in substance use frequency, substance use problems, and illegal behaviors 12 months after treatment entry than had they entered the community based outpatient programs. Results showed no evidence that youth who received MET/CBT5 would have fared better with respect to emotional problems, the likelihood of being institutionalized, or achieving a "recovery" status at 12 months had they received community-based treatments. The community-based treatments used in this study have not been assessed relative to "treatment as usual" but were selected as "exemplary" models of adolescent treatment. There is no evidence in this study that these exemplary programs yielded superior 12-month outcomes for the treatment of adolescents with marijuana problems; youth receiving MET/CBT5 experienced greater reductions in substance use and illegal activities. Thus, MET/CBT5 may be a promising treatment for community-based providers to adopt to treat these clients.