Iron‐Fortified Drinking Water in Anganwadi Centres in Rural India: A Randomized Controlled Trial

To reduce anaemia prevalence among children, we tested the introduction of cast iron ingots to prepare iron‐enriched drinking water in pre‐schools (Anganwadi centres) in Bihar, India. We implemented a randomized controlled trial among 820 Anganwadi centres with one control and two treatment arms, one arm receiving more comprehensive training and support than the other, between January and March 2020. As children's anaemia status could not be measured at follow‐up due to COVID‐19, we focused on intermediate steps and used observations of Anganwadi centres and a phone survey with Anganwadi workers to evaluate the intervention. Outcomes included the worker mentioning the newly introduced method without being prompted, the worker remembering detailed steps, and observed indications of the method's use in the centre. These outcomes capture key steps required to be fulfilled for the intervention to reduce anaemia: awareness of the method, knowledge of how to use it, and usage. While a large share of Anganwadi workers remembered the method and could explain its steps, indication of its usage was generally rare but more common in the intensive treatment arm. Successful implementation of the iron supplementation method in the daily routine of Anganwadi centres would require substantial improvements in their functionality.