Is behavioural activation an effective treatment for depression in children and adolescents? An updated systematic review and meta-analysis.

Behavioural Activation (BA)-a brief therapy based on the scheduling of enjoyable, purposeful and rewarding activities-is an effective and cost-effective treatment for depression in adults that shows promise for children and adolescents. We provide an update on a previous systematic review of evidence on BA-delivered in-person, telephone, or online-for depression and comorbid anxiety in children and adolescents. We conducted systematic literature searches in 6 databases up to February 2024. We included all study designs evaluating BA with participants up to 18 years old with diagnosable depression, as established by a validated screening tool or diagnostic manual. We used the Moncrieff Scale and the Cochrane Risk of Bias tool to assess study quality. We summarised the findings of all study types with a narrative synthesis and of randomised controlled trials (RCTs) with a meta-analysis. Overall, 24 studies (6 RCTs, 18 pre-post evaluations, n = 2,758) met our inclusion criteria. A meta-analysis of 4 RCTs (n = 156) showed that BA has a small effect of 0.24 (Hedge's adjusted g) in reducing depression symptoms compared to a waiting-list control, usual care and other therapies. Online and telephone-facilitated BA was shown to be feasible in 3 studies and effective in 1. Outcomes on comorbid anxiety were mixed. No economic evaluations met our inclusion criteria. BA shows sufficient promise as an intervention for reducing depression symptoms in children and adolescents to justify the need for further RCTs, providing that five conditions are met: studies are powered to detect a minimal clinically important difference; BA materials are fit-for-purpose to produce clinically meaningful change; follow-ups are longer than 6 months; primary outcomes are child-reported; and intervention costs, resource use and adverse events are reported.