Data collection and response rates
household‐level
Baseline data collection took place from November 2014 to February 2015, when most project activities were still in the planning or early implementation stages. Endline data collection took place from January to April 2019, about 1 year after the end of the project. Within the selected PSUs and SSUs, enumerators from the data collector SurveyMETER conducted a listing of households and drew a simple random sample of households with children in the relevant age range from this listing. If a household had more than one child 0–35 months old, one of the eligible children was randomly selected as the index child for sampling and survey purposes. If a sampled respondent was not successfully interviewed after three attempts, SurveyMETER randomly selected a replacement respondent with a child in the same age range as the sample respondent to meet the sample size targets.In sampled households, SurveyMETER enumerators interviewed the household head (or another household member who was knowledgeable about the household, if the household head was not available) and the sampled child's caregiver. Survey participants were told that they were being interviewed for a study of maternal and child health in their village, without mentioning the randomized controlled trial. The household head survey included questions about the background characteristics of household members, dwelling, assets, receipt of social benefits, and water and sanitation conditions. The caregiver survey included questions about maternal and child health outcomes such as health care utilization during and after pregnancy, breastfeeding and complementary feeding, and knowledge of caregiving practices. Instrument items were drawn from previous surveys whenever possible, such as the Indonesia Family Life Survey (IFLS), UNICEF Multiple Indicator Cluster Surveys (MICS) and indicators recommended by the World Health Organization WHO (Each field team included a supervisor, three household enumerators, and two anthropometrists, plus one enumerator for the health provider surveys described below. SurveyMETER provided 12 days of training to the enumerators (185) and anthropometrists (75). Anthropometrists had to pass a standardization test assessing the precision and accuracy of their techniques before being accepted into the data collection team. The anthropometrists conducted length and weight measurements for the sampled children using Seca brand scales and measuring boards. Per WHO protocol, children under 2 years old were measured for length lying down and children over 2 years old were measured standing. All measurements were conducted by two anthropometrists, and if the measurements were substantially different (more than 0.7 cm for length and more than 100 g for weight [De Onis et al., The household head and caregiver surveys were typically administered during the same visit as the anthropometric measurements, face‐to‐face in the respondent's home. These questionnaires were administered using Computer‐Assisted Personal Interview software, using laptops to enter data during the interview. The supervisor checked the entered data on a daily basis for completeness and consistency. In addition, the supervisor listened to recordings of the interviews to identify any problems with the interview process. The overall endline response rate was about 90% for household heads and caregivers and was almost identical in the treatment and control groups.In addition to household‐level surveys, SurveyMETER administered surveys to 2405 health service providers in the study areas, which included (1) village‐level health post volunteers and midwives and (2) subdistrict health centre‐level midwife coordinators, nutritionists, and sanitarians. These surveys focused primarily on capturing indicators of project exposure and implementation, such as participation in training and health care practices. SurveyMETER attempted to interview all of these types of providers located in the study areas and achieved a response rate of close to 100%.