Effectiveness of specialised nutritious food, local diet promotion and social and behaviour change communication in preventing stunting among children in Afghanistan: a mixed-method study protocol

A mixed-method observational study design will be employed, combining a prospective longitudinal cohort study, process evaluation and pre-post cross-sectional surveys. The intervention package will be implemented in two districts through health posts and community-based platforms. Lipid-based nutrient supplements for children aged 6-24 months and wheat-soya blend for PBW will be distributed monthly, along with SBCC sessions. Statistical analysis will use descriptive analysis, time-to-event analysis, generalised linear mixed models and thematic analysis for qualitative process evaluation. Expected outcomes include improved dietary diversity, reduced prevalence of stunting, underweight and wasting and enhanced weight and linear growth. Process evaluation will assess programme implementation fidelity, acceptability and dose-response relationships.