between April 2013 and March 2015. Even though it was not compulsory, participation in the behavioral accompanying measures was very high. The average attendance rate among cash transfer beneficiaries was 92%. Substantial participation of non-beneficiaries in assemblies held in beneficiary villages was also observed.<sup>16</sup> The follow-up survey was collected between mid-January and mid-May 2015. The survey again included two separate instruments: a household survey and a survey for children aged 6 to 59 months at followup. The household and child survey instruments were based on the baseline survey questionnaires. The child questionnaire included anthropometric measurements for children 6-59 months old as well as the test to measure cognitive development for children below 42 months. In addition, the strengths-anddifficulties questionnaire was introduced to measure socio-emotional development among children 2459 months old (Goodman, 1997).

The sampling strategy for the follow-up survey was designed to oversample actual program beneficiaries in the treatment groups. This was done to ensure sufficient statistical power to detect impacts of the behavioral intervention in the sub-sample of beneficiary households. Therefore, the follow-up sample was stratified based on the proxy means test score “predicted” from the baseline survey.<sup>17</sup> A total of 377 households from the baseline sample (with high predicted PMT scores, hence low likelihood of being selected as beneficiaries) were dropped from the follow-up sample. The distribution of these 377 households was balanced between the two treatment and control groups. Separately, an additional booster sample of 1,058 beneficiary households was randomly selected from the administrative database of beneficiaries and added to the follow-up sample. That booster sample is only added for the two treatment groups and used to estimate the value-added of the BCC component. Of the 5,011 households in the follow-up sample, 4,818 were tracked and interviewed, a response rate of 96.1%.<sup>18</sup> Table 1 summarizes the composition of the follow-up sample, which we discuss in more detail in the next section.

> 16 A participation rate for non-beneficiaries cannot be calculated as their participation was not recorded nominally. 17 Specifically, all the households with a proxy means test score below 1.05 times the beneficiary selection threshold were selected, while half the households with a proxy means test score above 1.05 times the beneficiary selection threshold were selected. Stratification was based on the PMT score “predicted” from the baseline survey so that the sampling process would remain similar in the treatment and control group.

> 18 The follow-up survey used the SurveySolutions electronic data collection platform. Questionnaires with pre-filled data were downloaded from an online server onto supervisors’ laptops, and later transferred to enumerators’ tablets. Consistency checks were integrated in the Surveysolutions CAPI application installed on enumerators’ tablets. Upon completion of the questionnaires and synchronization back to supervisors’ laptops, supervisors were responsible for validating questionnaires before uploading them to the server. A dedicated team of quality controllers verified the data once uploaded to the server. Automated consistency checks were also performed.  As for the baseline survey, household and child survey teams followed each other in the field. Household survey teams were responsible to identify children eligible for the child survey. The list of children obtained by the household survey team provided the sample for the child survey. To ensure a smooth transition

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