Evaluating Brief Behavioural Activation for depression in adolescents with acquired brain injury using a single-case experimental design.

Background: Adolescents who have had an acquired brain injury (ABI) commonly experience depression. Brief Behavioural Activation (Brief BA) is a successful, values-based intervention for managing depression in neurotypical adolescents. This study investigated the effectiveness of Brief BA, using a single-case experimental design, with adolescents experiencing depression following ABI. Methods: Five adolescents, one male and four female, aged 14-17 years and with ABI, completed a 6-week course of Brief BA. The primary outcome measures were mean daily activity scores out of 10 for 'achievement', 'closeness' and 'enjoyment' (mean achievement, closeness and enjoyment scores; MACES). MACES were collected daily for 9 weeks, comprising at least 2 weeks at baseline and at least 6 weeks during the intervention. Secondary outcome measures of depression, quality of life (QoL), and participation were collected once at baseline, immediately post-treatment, and at a 4-week follow-up. Results: Two participants showed a significant increase in enjoyment scores and one participant showed a significant increase in closeness scores. No other significant differences were noted for MACES. All participants reported significant reliable improvement in depression scores at their follow-up sessions, with three showing clinically significant improvement. Three participants reported reliable improvement in QoL. All parents reported reliable improvement in participants' depression and QoL scores. No significant changes were noted for participation scores. Conclusion: The significant changes in closeness and enjoyment scores following intervention suggest Brief BA may encourage positive behavioural change for adolescents with depression following ABI. Discussions explore the potential role of insight through linking valued activities with mood and positive reinforcement, leading to an improvement on depression and QoL outcomes. Charities and services providing low-intensity interventions might want to consider trialling Brief BA for this population. Future research suggestions, such as investigating Brief BA for depression linked with more diverse neurological conditions, are discussed.