Concentrated Cognitive-Behavior Therapy for Unmedicated Children and Adolescents With Obsessive-Compulsive Disorder in Routine Clinical Care: A Randomized Controlled Trial With a 6-Month Naturalistic Follow-up.

Cognitive-behavior therapy (CBT) is effective for obsessive-compulsive disorder (OCD). Because CBT requires significant time and resources, there is an increased interest in developing shorter formats of CBT for OCD (i.e., fewer sessions or in less time). We conducted a randomized single-blind controlled trial to investigate the effectiveness of concentrated CBT (co-CBT; 20 hours of therapist time across one month) compared to a waiting list (WL) in 30 unmedicated children and adolescents with OCD aged 7-17 in routine clinical care. Co-CBT was superior to the WL in reducing OCD symptom severity at posttreatment (primary endpoint; Cohen's d = 1.76) and these results were maintained through the end of a naturalistic 6-month follow-up. Participants initially randomized to the WL were offered co-CBT at the end of the trial and post-hoc analyses showed that they had similar improvements to those initially randomized to co-CBT. In post-hoc predictor analyses, participants aged 7-12, compared to those aged 13-17, and those with higher baseline OCD severity showed better posttreatment outcomes. Co-CBT is an effective intervention for unmedicated children and adolescents with OCD in routine clinical care. Studies including more robust control groups and larger samples are needed to replicate and expand these findings. Trial registration number: NCT04042038.