How can school-based programmes improve physical and mental health outcomes in low-and-middle-income countries? An umbrella review and logic model

School-based programmes offer a promising approach for improving physical and mental health trajectories in low-and-middle-countries (LMICs). This umbrella review and logic model explores how and in which contexts these programmes are effective. A systematic search of electronic databases identified 20 systematic reviews (5 meta-analyses) on school based (SB) physical (n = 13; primary studies = 214) and mental (n = 7; primary studies = 120) health programmes across a range of low, lower-middle, and upper-middle income countries. Programmes included universal (all students), selective (e.g., high-risk students), and indicated (e.g., students with symptoms) approaches. Evidence was stronger for proximal (e.g., nutritional knowledge), and intermediate (e.g., dietary behaviour) outcomes than for distal (e.g., obesity reduction) outcomes, and there were some variations in outcome by geographical region. Evidence for combined physical and mental health programmes was scant, with limited overlap between the two types of programmes (i.e. some shared components and outcomes). Moderators of programme effectiveness included recipient (e.g., gender, age) and programme (e.g., longer duration, multi-component) characteristics, and inner (e.g., school resources, support for teachers) and outer (e.g., partnerships with Non-Governmental Organisations) settings. Cultural adaptations and implementation quality were highlighted as important (yet rarely fully reported) factors in ensuring programme sustainability and scaling-up. There is some supportive evidence for SB programmes in LMICs, though evidence for effectiveness varies by temporality of outcome and geographical location. This highlights the importance of considering implementation barriers across outcome trajectories and ensuring sufficient attention is given to cultural adaptations. Dual programmes combining balanced physical and mental health modules might offer promise for addressing the growing burden of non-communicable diseases in LMICs.