ABSTRACT
BACKGROUND AND AIMS: Treatment completion is associated with improved alcohol and other drug (AOD) treatment outcomes. Unfortunately, treatment disengagement is common, particularly among young people. We reviewed and synthesised research on AOD treatment completion and/or early disengagement among young people. METHODS: We conducted a systematic review and meta-analysis of studies reporting on completion rates and/or early disengagement from psychosocial AOD treatment among adolescents and young adults. An overall estimated treatment completion rate was calculated using inverse-variance random effects meta-analysis, and random-effects meta-regression was used to identify between-study level moderators of completion rate. We completed a narrative review summarising literature on early treatment disengagement and within-study level correlates of treatment completion. Study quality was assessed using the EPHPP. RESULTS: Of the 6158 studies screened, we retained 410 for full text review and included 98 studies in the review. Treatment completion rates were reported in 88 studies, and early disengagement rates were reported in 13. The estimated overall treatment completion rate was 59 % (95 % CI=57-61 %), with experimental studies reporting higher rates of completion than observational studies. There was limited evidence for demographic or substance-related correlates of treatment completion. Contingency management was associated with increased completion rates, as was family-based intervention. CONCLUSIONS: Disengagement from AOD treatment among youth populations is common and contributes to poor treatment outcomes. Existing research has yielded little consensus on the factors associated with treatment completion. The use of contingency management strategies and involving family/social supports in treatment were identified as potential avenues for promoting ongoing treatment engagement.