Implementing school-based nutrition interventions in low- and middle-income countries: a scoping review of implementation strategies, frameworks, and outcomes.

School-based nutrition interventions are widely used to improve nutrition among children and adolescents in low- and middle-income countries. This scoping review examined implementation strategies, theories, models, frameworks, and implementation outcomes reported for school-based nutrition interventions in these settings. We included English-language primary studies conducted in school settings in low- and middle-income countries if they reported implementation strategies, implementation outcomes, theories, models or frameworks, barriers, facilitators, adaptation, sustainability, scale-up, or implementation processes. PubMed and Scopus were searched, and reference lists of included studies and relevant reviews were screened. Records were screened independently by two reviewers, and data were synthesized descriptively and thematically. The search identified 1,985 records, and eight studies met the inclusion criteria. The studies were conducted in Nepal, Ghana, Pakistan, Tanzania, and India. Implementation strategies included teacher-led delivery, training, stakeholder and community engagement, external partnership support, and integration into school systems. Reported barriers included limited funding, inadequate infrastructure, staff workload, weak coordination, limited monitoring, and dependence on external or parent contributions. Separately, implementation reporting was incomplete, particularly for reach, fidelity, and sustainability. Because the search was restricted to two databases and English-language publications, some relevant evidence may have been missed. Future studies should report implementation processes and outcomes more clearly to support adaptation, scale-up, and long-term delivery.