Effect of Adding Milk to a Micronutrient-Fortified High-Energy Biscuit School Feeding Programme in Yemen: A Cluster-Randomized Controlled Trial.

Background: Two billion children globally are estimated to live in conflict-affected areas. School feeding programs (SFPs) are a widely implemented safety net that supports children during and after conflict.

Objectives: We evaluated the effectiveness of providing milk alongside a high-energy biscuit (HEB) SFP in Yemen on children's and caregivers' outcomes.

Methods: We implemented a 2-arm longitudinal cluster-randomized controlled trial from December 2023 to May 2024. Forty-two schools in Al Mukha district were randomly assigned (1:1) to control, where children received HEBs (2 packets [100 g] daily), or milk, where children received HEBs plus a 120 mL carton of ultra-high temperature milk. Children aged 6-18 y were randomly selected for enrolment. The primary outcomes were children's dietary diversity and milk consumption. Secondary outcomes were children's cognition, learning, attendance, nutritional status, and health. Tertiary outcomes were child and caregiver mental health and household food security. We conducted intent-to-treat analysis using linear mixed-effects models accounting for clustering.

Results: One thousand two hundred ninety-nine children were enrolled. After 5 mo, the intervention increased milk consumption but had no effect on dietary diversity. Children's cognition [mean difference (MD): 1.00 (95% CI: 0.40, 1.61)], literacy [MD: 1.14 (95% CI: 0.36, 1.92)], and numeracy [MD: 1.06 (95% CI: 0.46, 1.67)] scores improved. Cough symptoms declined: MD: -0.12 (95% CI: -0.2, -0.03). There were no changes in school attendance or nutritional status. The intervention reduced conduct problems in children [MD: -0.52 (95% CI: -0.97, -0.08)], severe anxiety in caregivers [MD: -0.03 (95% CI: -0.06, -0.001)], and household severe food insecurity [MD: -0.09 (95% CI: - 0.17, -0.001)].

Conclusions: Adding a daily milk drink to an HEB SFP in Yemen resulted in numerous benefits for children and their families. Hybrid models to incrementally improve meal quality are feasible, acceptable, and lead to meaningful impacts. More research is needed on medium- and long-term benefits.

Registration: The trial was registered with ISRCTN (ISRCTN12225603).