The effectiveness of third wave cognitive behavioural therapies for children and adolescents: A systematic review and meta‐analysis

Objectives Third wave cognitive behavioural therapies are increasingly used with children and adolescents. This meta‐analysis aimed to determine the effectiveness of four third‐wave interventions (acceptance and commitment therapy, compassion focused therapy, mindfulness‐based cognitive therapy, and metacognitive therapy) for youth. Methods Four electronic databases were used to identify randomized controlled trials, which tested effects related to health, well‐being and functioning. Sensitivity analyses considering study quality were conducted and moderators were explored. Results The results based on 50 RCTs meeting inclusion criteria indicated emotional symptoms/internalizing problems (g = −.68, 95% CI −.98 to −.37, k = 43, N = 3265), behavioural difficulties/externalizing problems (g = −.62, 95% CI −1.01 to −.22, k = 23, N = 1659), interference from difficulties (g = −.46, 95% CI −.87 to −.05, k = 21, N = 1786), third wave processes (g = .39, 95% CI .17 to .62, k = 22, N = 1900), wellbeing/flourishing (g = .76, 95% CI .35 to 1.17, k = 21, N = 1303) and physical health/pain (g = .72, 95% CI .01 to 1.44, k = 9, N = 1171) yielded significant effects. Effect for quality of life (g = .62, 95% CI −.08 to 1.31, k = 12, N = 1271) was non‐significant. When analysing only those studies rated moderate‐high quality, third wave interventions yielded significant superiority effects compared to controls for emotional symptoms/internalizing problems (g = −.55, 95% CI −.82 to −.27, k = 28, N = 2110), interference from difficulties (g = −.48, 95% CI −.90 to −.05, k = 21, N = 1605), third wave processes (g = .27, 95% CI .11 to .43, k = 18, N = 1692), well‐being/flourishing (g = .50, 95% CI .18 to .81, k = 16, N = 1063), and quality of life (g = .32, 95% CI .04 to .60, k = 10, N = 1212). Behavioural difficulties/externalizing problems (g = −.38, 95% CI −.86 to .10, k = 15, N = 1351) and physical health/pain (g = .52, 95% CI −.14 to 1.17, k = 8, N = 1139) ceased to be significant. Widespread heterogeneity raised concerns about generalizability and follow‐up data was relatively sparse. Conclusions This meta‐analysis finds promising results for use of third wave CBT with youth, though the review has limitations.