Protocol for integrated solutions for healthy birth, growth and development: a cluster-randomised controlled trial to evaluate the effectiveness of a mixed nutrition intervention package in reducing child undernutrition in Lao People's Democratic Republic.

Introduction: While Lao People's Democratic Republic has seen economic gains in recent years, one-third of children aged 5 years and under are stunted. There is a need for evidence around clinically effective and cost-effective integrated nutrition-specific and nutrition-sensitive interventions in the local context.

Methods and analysis: We aim to conduct a cluster-randomised control trial to test the effectiveness of an integrated package of community-based nutrition-specific and nutrition-sensitive interventions compared with the standard government package of nutrition actions. The trial will be in six districts within the province of Vientiane. We will recruit pregnant women in their third trimester and follow the children born to them every 6 months until 18 months of age. A total of 256 villages (serviced by 34 health centres) will be randomised to a control arm or an intervention arm using a minimisation algorithm. The primary outcome is the prevalence of stunting among children aged 6, 12 and 18 months. The secondary outcomes include prevalence of low birth weight and wasting among children aged 6, 12 and 18 months. Analyses for the primary and secondary outcomes will be conducted at the mother-infant dyad level and adjusted for the cluster randomisation. The difference in prevalence of low birth weight, wasting and stunting between control and intervention groups will be assessed using Pearson's χ² tests and 95% CIs for the group difference, adjusted for clustering.

Ethics and dissemination: The trial protocol was approved by the Alfred Human Research Ethic Committee (Ref: 227/16) and the Lao National Ethics Committee for Health Research (Ref: 81). The trial was registered with the Australian New Zealand Clinical Trials Registry on 28 April 2020 (ACTRN12620000520932). The results will be disseminated at different levels: study participants; the local community; other Lao stakeholders including policymakers; and an international audience.

Trial registration number: Australia New Zealand Clinical Trials Registry: ACTRN12620000520932.