RESUMO
INTRODUCTION: Recently, acceptance- and commitment therapy (ACT) gained increasing interest. Studies show good efficacy in the treatment of patients presenting with several psychologic and somatic complaints. The present systematic review and meta-analysis addresses effectiveness of ACT-based interventions to reduce stress in children, adolescents, and young adults compared to control conditions. METHODS: The meta-analysis was pre-registered at PROSPERO (CRD42019117440). Randomized controlled trials (RCTs) and quasi-randomized controlled trials (qRCT) in German or English language comparing the effects of ACT-based interventions to control conditions (e.g., treatment as usual, waitlist control) on stress-related outcome measures in youth were considered for inclusion. The target population was subjects 0-18 years of age. The databases PubMed, PsychInfo, Cochrane Database, CINAHL, and Web of Science were searched systematically up to July 2023. A random effect meta-analysis and a risk of bias assessment according to the procedure outlined in the Cochrane Handbook of Systematic Reviews were conducted. RESULTS: The search resulted in 187 studies, of which eight studies with 976 participants were finally subjected to meta-analysis. Studies implemented ACT both in school-based group settings and in single settings and both as a universal and indicated prevention. Analyses yielded a significant main effect (Hedges' g = -0.20; 95% confidence interval [-0.36; -0.05]), indicating that interventions based on ACT resulted in greater reduction of stress compared to control conditions. CONCLUSION: ACT appears effective at reducing stress in youth. Further research is needed due to methodological shortcomings of existing studies. Small sample sizes, heterogenous studies, methodological shortcomings, and evidence of publication bias limit the conclusions that can be drawn from this meta-analysis.