Practitioner Review: effectiveness of indicated school-based interventions for adolescent depression and anxiety - a meta-analytic review

Background: Interest in delivering psychological interventions within schools to facilitate early intervention is increasing. However, most reviews have focused on universal or preventative programmes rather than interventions designed to decrease existing symptoms of depression or anxiety. This paper aims to provide a meta-analytic review of randomised controlled trials of indicated psychological interventions for young people aged 10-19 with elevated symptoms of depression and/or anxiety. Methods: Eight electronic databases were systematically searched from inception to April 2019 for eligible trials. Study quality was assessed using two scales designed to evaluate psychotherapy intervention trials. Random effects meta-analyses were conducted separately for trials that recruited participants based on symptoms of depression and based on symptoms of anxiety. Results: Data from 45 trials were analysed. Most interventions studied used cognitive and behavioural strategies. Few studies met methodological quality criteria, but effect size was not associated with study quality. Indicated school-based interventions had a small effect on reducing depression symptoms (SMD = 0.34, 95% CI -0.48, -0.21) and a medium effect on reducing anxiety symptoms (SMD=-0.49, 95% CI -0.79, -0.19) immediately post-intervention. Subgroup analyses indicated that interventions delivered by internal school staff did not have significant effects on symptoms. Reductions in depression were maintained at short-term (≤6 months) but not medium (>6 months ≤12) or long-term (>12 month) follow up. Reductions in anxiety symptoms were not maintained at any follow up. Conclusions: Indicated school-based interventions are effective at reducing symptoms of depression and anxiety in adolescents immediately post-intervention but there is little evidence that these reductions are maintained. Interventions delivered by school staff are not supported by the current evidence-base. Further high quality randomised controlled trials incorporating assessment of longer-term outcomes are needed to justify increased investment in school-based interventions for adolescent depression and anxiety