treatment group is defined as the 100 sectors that implemented the demand-side incentives and the control group is defined as the 98 sectors that did not (see Figure 1).

A baseline survey was fielded from February to May 2010 to measure outcomes prior to the launch of the program and to establish internal validity of the experimental design. For a household level survey, twelve households with a woman aged 15-49 with a recent pregnancy or birth were selected from the catchment area of each of the 198 health centers. First, three cells (groups of villages) were randomly selected and four villages within each cell were randomly selected.<sup>7</sup> In each village, a field supervisor consulted the village leader and/or community health workers in order to identify the household with the most recent birth in each village. This resulted in a sample of 2,376 households.

A follow-up survey took place from November 2013 to June 2014.<sup>8</sup> The survey teams returned to the same villages sampled for the baseline and identified the households with the most recent birth or pregnancy following the same procedure as in the baseline survey.<sup>9</sup> Interviews were completed with 2,343 households. A rate of above 98.5% of successful interviews was achieved in all study arms. The follow-up survey also collected data on the 198 health centers whose catchment areas include the selected villages.

The primary outcomes for this analysis were constructed using data from interviews with the women who were pregnant shortly before the survey. A detailed questionnaire was administered to gather information on the care given to these women throughout their most recent pregnancy, delivery and post-partum. The analysis therefore relies on self-reported measures of service utilization.

The follow-up survey was fielded about nine months after the last funds for procurement of gifts were disbursed to the health centers. The survey was designed to not only evaluate the demand-side scheme but to collect data on the overall CPBF program. The termination of transfers to the health centers was unexpected and was not announced. As we will report below, almost all health centers in the treatment group reported they were still providing gifts as a policy although facing stock outs. Ideally, the data would have been collected while the program was still fully implemented.

To assess how the delayed data collection might affect the impact estimates and how the impact might have changed since implementation started, we complement the analysis conducted with the CPBF impact evaluation data with analysis of the Rwanda Demographic and Health Survey data collected from November 2014 to April 2015. The nationally representative survey collected detailed retrospective data on births in the five years preceding the survey. Timing of antenatal and postnatal care is reported by women for their most recent pregnancy. While the RDHS provides data on which district each survey cluster (enumeration area) is, we are uncertain about the exact sector. The GPS coordinates of clusters are randomly displaced to ensure confidentiality. Rural clusters are displaced up to five kilometers and urban clusters are displaced up to 2 kilometers.<sup>10</sup> Out of the 492 RDHS clusters, 304 are in the 19

> 7 During the fieldwork, the survey team learned that some villages, in five of the sectors, were served by health facilities different from the health center selected for the sample. In these cases, additional households in the villages covered by the selected cooperatives were added to the sample.

> 8 The duration of the follow-up survey was longer because in addition to a sample of women with recent pregnancies, the women interviewed in the baseline were tracked even if they relocated outside their baseline village.

> 9 In 32 villages, the same woman was interviewed both at baseline and follow-up surveys.

> 10 One percent of rural clusters displaced up to 10 kilometers

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