Systematic Review of Organizational Strategies to Promote the Sustainability and Scale-Up of Mental Health Interventions to Advance Youth Psychological Wellbeing.

This systematic review synthesizes empirical research on organizational strategies that support the sustainability and scale-up of community-based interventions designed to promote youth psychological well-being. While research has established the effectiveness of youth mental health interventions in community contexts, less is understood about the processes that ensure their long-term sustainability and scale-up. A search across seven databases yielded 27 eligible empirical studies (2003-2025) including peer-reviewed and grey literature. The Synthesis without Meta-analysis (SWiM) and the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) standards provided a framework for conducting and documenting the review. Evaluations of methodological quality were carried out using Strengthening the Reporting of Observational Studies in Epidemiology (STROBE), Consolidated Standards of Reporting Trials (CONSORT), and the Critical Appraisal Skills Programme (CASP). Two dominant strategies for intervention retention and effectiveness were identified: training and technical assistance (12 studies, 44%) and capacity building with implementation support (12 studies, 44%). The main barriers to sustainability and scale-up were reported as staffing as well as other resource limitations (financial, human, and technical), while facilitators included strong communication and leadership, sufficient funding and partnerships, and access to training and technology. Eleven studies (41%) sustained interventions beyond the initial funding period, with key factors including intervention fidelity, agency incentives, organizational support, therapist retention, and stakeholder engagement. The findings highlight the potential benefits of embedding sustainability and scale-up strategies in the pre-implementation phase, anticipating foreseeable barriers, and considering intervention fidelity, workforce stability, and organizational readiness as important precursors to sustainability and scale-up.