Field procedures and data handling
Data were collected by the research field teams using a structured questionnaire, translated into Somali, on mobile Android devices running Open Data Kit (ODK). Data collection at baseline (month 0), midline (after 3 months of intervention), and endline (after 9 months of intervention) was conducted by study enumerators, who were hired specifically for the data collection exercises. Data were collected at the monthly time points in between 0, 3, and 9 months by CHWs. Prior to starting data collection, we implemented 1-week training sessions for enumerators and supervisors at R1, R3, and R9 data collection rounds. During these training sessions, we piloted and revised questionnaires. The R1, R2, and R3 data collection was undertaken by 10 teams. Each team had an enumerator and 2 CHWs. The rest of data collection rounds were conducted by 10 teams of CHWs, with each team having 2 members. Teams in all rounds were supervised by 4 nutrition supervisors, under the overall supervision of a field study coordinator. During each round of data collection, if we could not reach a household after repeated attempts or any of its members were absent, we enquired about the reasons for this absence from family or neighbours.