Longitudinal substudy
death
We conducted a longitudinal substudy among a randomly selected subset of households enrolled in the sanitation and control arms of the WASH Benefits study to leverage the design and infrastructure of the large-scale randomized controlled trial. Four households per cluster were randomly selected from each sanitation cluster and from one of two control clusters in the same block, maintaining the pair-matched design of the parent trial and resulting in a sample size of 720 households (360 per arm). Households were eligible for enrollment in the substudy if the index child was alive and available or if there was another child <24 months available in the household in the case of index child death.We visited households enrolled in the substudy approximately quarterly for a total of 8 visits between 1 and 3.5 years after intervention initiation by the parent trial. Therefore, the substudy period captured approximately one year (substudy visits 1–3) with intensive promotion activities among intervention recipients, one year (substudy visits 4–6) with less intensive promotion and six months (substudy visits 7–8) with no promotion. At each visit, field staff observed indicators of access to and use of latrines, potties and sani-scoops through spot check observations and also recorded self-reported latrine use, maintenance, sharing and pit emptying practices, and self-reported use of potties and sani-scoops/similar tools through structured questionnaires. Latrine use was separately reported for adults and child age groups with different expected defecation practices (<3 years, 3–8 years, 8–15 years).