Internet and Computer-based Cognitive Behavioral Therapy for Anxiety and Depression in Adolescents and Young Adults: A Systematic Review and Meta-analysis. (Preprint)

BACKGROUND Anxiety and depressive disorders are prevalent in adolescents and young adults. However, the majority of young people with mental health problems do not receive treatment. Computerized cognitive behavior therapy (cCBT) may provide an accessible alternative to face-to-face treatment, but the evidence base in young people remains limited compared to adults. OBJECTIVE The objective of this study was to provide an up-to-date comprehensive systematic review and meta-analysis of the effectiveness of cCBT in treating anxiety and depression in adolescents and young adults compared to active treatment controls and passive controls. We aimed to examine post-treatment and follow-up effects, and to explore moderators of treatment effects. METHODS We conducted systematic searches in six electronic databases: PubMed, EMBASE, PsycINFO, CINAHL, Web of Science, and Cochrane Central Register of Controlled Trials. We included randomized controlled trials comparing cCBT with any control group in adolescents or young adults (mean age between 12 and 25 years) with anxiety or depressive symptoms. Quality of included studies was assessed using the Cochrane risk-of-bias tool for randomized trials, version 2.0. Overall quality of the evidence for each outcome was assessed using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. Post-treatment means and standard deviations were compared between intervention and control groups, and pooled effect sizes (Hedges' g) were calculated. Random-effects meta-analyses were conducted using Comprehensive Meta-Analysis software. Subgroup analyses and meta-regression analyses were conducted to explore whether age, level of guidance, and adherence rate were associated with treatment outcome. RESULTS The database search resulted in 7670 papers, of which twenty-four studies met inclusion criteria. Most included studies (22/24) had a high risk of bias due to self-report measures and/or inappropriate handling of missing data. Compared to passive controls, cCBT yielded small to medium post-treatment pooled effect sizes on depressive symptoms (g=0.51, 95%CI 0.30-0.72, numbers-needed-to-treat [NNT]=3.55) and anxiety symptoms, (g=0.44, 95%CI 0.23-0.65, NNT=4.10). cCBT yielded similar effects as active treatment controls on anxiety symptoms (g=0.04, 95% CI -0.23-0.31). For depressive symptoms, the non-significant pooled effect size favored active treatment controls (g=-0.70, 95%CI -1.51-0.11), but heterogeneity was very high (I2 = 90.63%). No moderators of treatment effects were identified. At long-term follow-up, cCBT yielded a small pooled effect size on depressive symptoms compared to passive controls (g=0.27, 95%CI 0.09-0.45, NNT=6.58). No other significant follow-up effects were found; however, power was limited due to the small number of studies. CONCLUSIONS cCBT is beneficial for reducing anxiety and depressive symptoms at post-treatment in adolescents and young adults compared to passive controls. Compared to active treatment controls, cCBT yielded similar effects on anxiety symptoms. Regarding depressive symptoms, however, results remain unclear. More high-quality research in this population is needed, including active controls and long-term follow-up assessments. CLINICALTRIAL