Abstract
BACKGROUND: Depressive disorders are common in adolescence and are associated with a wide range of negative long-term outcomes. Highly controlled randomized controlled trials (RCT) provide considerable evidence for the efficacy of cognitive-behavioral therapy (CBT) as a treatment for depression, but studies examining the effectiveness of CBT in clinical settings are very rare . METHODS: In the present observational study, the changes achieved through routine CBT in adolescents with depressive disorders treated in a clinical setting in terms of a university outpatient clinic were analyzed, and compared to a historical control group of adolescents with depressive disorders who had received treatment as usual. At the start and end of treatment (pre- and post-assessment), parent and self-ratings of the German versions of the Youth Self-Report (YSR), the Child Behavior Checklist (CBCL) and rating scales for depressive symptoms (FBB-DES, SBB-DES) were assessed. A total of 331 adolescents aged 11-18 years with complete data were assessed for the main analysis. RESULTS: The analysis yielded small to large pre-post effect sizes (Cohen's d) for the total sample (d = 0.33 to d = 0.82) and large effect sizes for adolescents who were rated in the clinical range on each (sub) scale at the start of treatment (d = 0.85 to d = 1.30). When comparing patients in the clinical range with historical controls, medium to large net effect sizes (d = 0.53 to d = 2.09) emerged for the total scores in self- and parent rating. However, a substantial proportion of the sample remained in the clinical range at the end of treatment. CONCLUSIONS: These findings suggest that CBT is effective for adolescents with depressive disorders when administered under routine care conditions, but the results must be interpreted with caution due to the lack of a direct control condition. TRIAL REGISTRATION: DRKS, DRKS00021518 . Registered 27 April 2020 - Retrospectively registered, http://drks.de.