Indicated preventive interventions for depression in children and adolescents: A meta-analysis and meta-regression.

Depression contributes about 2% to the global burden of disease. A first onset of depressive disorder or subsyndromal depressive symptoms is common in adolescence, indicating that early prevention is a priority. However, trials of preventive interventions for depression in youths show conflicting results. This systematic review and meta-analysis investigated the effectiveness of group-based cognitive behavioral therapy (GB-CBT) as a preventive intervention targeting subsyndromal depression in children and adolescents. In addition, the impact of different covariates (type of comparator and use of booster sessions) was assessed. Relevant articles were identified from previous systematic reviews, and supplemented with an electronic search spanning from 01/09/2014 to 28/02/2018. The retrieved articles were assessed for eligibility and risk of bias. Relevant data were extracted. Intervention effectiveness was pooled using a random-effects model and the impact of covariates assessed using meta-regression. 38 eligible articles (34 trials) were obtained. The analysis showed GB-CBT to significantly reduce the incidence (relative risk 0.43, 95% CI 0.21-0.87) and symptoms (Cohen's d -0.22, 95% CI -0.32 to -0.11) of depression at post-test compared to all controls. Comparisons with passive comparators suggested that the effect decayed over time. However, compared to active controls, a significant intervention effect was evident only after 12 month or more. Our results suggest that the preventive effect of GB-CBT wears off, but still lasts longer than the effect of active comparators. Only a few studies included booster sessions, precluding firm conclusions. Future studies should clarify to what extent maintenance strategies can prolong the preventive effect of GB-CBT.