Abstract
INTRODUCTION: Adolescents in many low- and middle-income countries are frequently exposed to adversities such as armed conflicts and economic hardship. These stressors occur during a critical developmental period marked by profound physical, social, and psychological changes, increasing vulnerability to mental disorders. To address this mental health-care need, the World Health Organization (WHO) and the United Nations Children's Fund (UNICEF) developed Early Adolescent Skills for Emotions (EASE), a 10-session group intervention for adolescents and their caregivers. This systematic review summarizes current evidence regarding the effectiveness and implementation of EASE. METHODS: We searched five electronic databases up to July 26, 2025, for trials evaluating the effects of EASE on adolescents' mental distress and caregivers' parenting behaviors. Random-effects multilevel meta-analyses were conducted using standardized mean differences (SMDs) at post-intervention and 3-month follow-up, complemented by a qualitative synthesis of implementation outcomes. Preregistration ID: CRD42023488490. RESULTS: No evidence was found for superiority of EASE over a 1-session psychoeducation control on overall mental distress or caregiver outcomes. However, for the primary outcome, internalizing symptoms, there was strong evidence of a very small to small favorable effect at post-intervention, SMD = -0.17, 95% CI: [-0.31, -0.04], which was maintained at follow-up. Implementation studies indicated that EASE is acceptable, feasible, and delivered with good fidelity; yet low caregiver engagement and contextual challenges hindered implementation. CONCLUSION: Observed effects were smaller than those reported for a comparable WHO intervention for adults, highlighting substantial scope for optimization. Additional high-quality trials are warranted to improve the effectiveness of EASE and maximize its potential public health impact.