Public health interventions to improve the mental health and mental health literacy of young people in resource-limited settings: a systematic review.

Background: Young people aged 15-29 experience a substantial mental health burden, with major depressive disorder (MDD) and schizophrenia accounting for as much as half of this burden. Young people living in low- or middle-income countries (LMICs) face challenges to improving their mental health. A substantial treatment gap exists, driven by resource constraints and workforce shortages. Addressing mental health and mental health literacy through public health interventions has the potential to reduce the burden of mental disorders in this population, while meeting the needs of resource-limited settings. Understanding how best to design public health interventions to address both mental health and mental health literacy is key to effectively using resources and maximising benefits. Methods: Electronic database searches (MEDLINE, Embase, CENTRAL, PsycINFO) were supplemented with non-English database searches (Global Index Medicus, African Journals Online), searches of conference proceedings and other grey literature sources. Eligible studies were conducted in resource-limited settings and reported characteristics of public health interventions. ≥80% of the study population was required to be aged 15-29 years, with MDD and/or schizophrenia. Results: 5,339 records were identified in database searches; 30 studies (26 on MDD and 4 on schizophrenia) were included. Most studies (25 of 30) presented a behaviour therapy intervention, often based on an existing framework (e.g., CBT, behaviour activation). 10 studies incorporated digital health in their programme design, including electronic/computerised versions of behaviour therapy interventions and messaging services to allow participants to contact facilitators for support. Intervention outcomes were assessed using pre-existing validated tools such as Beck Depression Inventory-II (BDI-II) and the 12-item Discrimination and Stigma scale (DISC-12), often adapted to the local context. Mental health literacy outcomes included social support, self-efficacy and cognitive re-appraisal. 25 studies reported statistically significant improvements in mental health outcomes following intervention, compared to baseline and/or usual care. Outcomes were generally assessed over short follow-up durations of ≤6 months. Conclusion: These findings demonstrate the potential for public health interventions, enabled by digital health, to improve mental health literacy and outcomes in LMICs. Other considerations for programme design included adaptation of pre-existing intervention frameworks and use of validated tools to evaluate outcomes. Systematic review registration: https://www.crd.york.ac.uk/PROSPERO/view/CRD42024579598.