## **3.1.3 Participant Selection**

Toward the end of 2017, in collaboration with the Project Implementation Unit, we conducted a census of 45,883 households across the 280 localities to identify eligible girls. Girls were considered eligible for community safe spaces if they were 8–24 years old and had never been to school or did not go to school during the academic year 2017/2018. Priority was given to orphans, single mothers, pregnant girls and girls considered most vulnerable to early marriage and early pregnancies based on a household vulnerability index.<sup>7</sup> From the eligible population, we sampled a fourth of the total eligible girls who were aged 12–24 to be part of the impact evaluation sample.

# **3.2 Data**

We use two rounds of data collection: first, a baseline survey conducted before the implementation of the interventions between December 2017 and January 2018; and second, a follow-up survey conducted approximately one year after the end of the interventions, between January and March 2021. The follow-up survey was done in-person despite the disruption caused by the COVID-19 pandemic, and followed national health guidelines. Two main questionnaires were used: the household questionnaire and the adolescent girl questionnaire. The household questionnaire, completed by the household’s head or their representative, collected data on the household’s living conditions (e.g., nutrition, assets, and shocks) as well as demographics from every household member (e.g., education, marriage, and pregnancy).

The adolescent girl questionnaire collected information on various domains, including marriage and fertility behaviors, aspirations, socio-emotional skills (collected only at followup), mental health (collected only at follow-up), gender attitudes, gender-based violence (collected only at follow-up), decision-making in the household, income-generating activities, and access to finance. Gender-based violence (experience of emotional, physical, and sexual violence) is measured using questions adapted from the DHS survey. Girls’ mental health is measured using the GHQ-12 (General Health Questionnaire, 12 items), a tool used to detect common mental disorders.<sup>8</sup> The measures of socio-emotional skills used were developed as part of the Effective Socio-emotional Skills to Gain Economic Empowerment (ESTEEM) initiative at the Africa Gender Innovation Lab.<sup>9</sup> At baseline, the total sample size was 3,792 adolescent girls and their respective households. At follow-up, despite an intensive tracking exercise, only a total of 3,007 adolescents girls were successfully interviewed along with 3,680 of their baseline households. This resulted in an average attrition rate of 20% of the total baseline sample of adolescent girls. Tests for differential attrition are presented in table A1 in the appendix. The attrition rate in

> 7In households with more than one eligible girl, only one beneficiary was selected by lottery, unless the number of eligible girls was less than ten in the locality.

> 8Statements used to construct the gender equality, violence, socio-emotional skills and mental health indices are listed in tables A5 and A6 in the appendix.

> 9For more details, see Marsh et al. (2025).

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