community poverty status. Within each stratum, a random sample totaling 46 districts was drawn.<sup>9</sup> Five schools were randomly selected within each district.<sup>10</sup> The resulting sample was nationally representative of Egyptian schools with KGs.

A total of 214 schools were sampled for the diagnostic research tool.<sup>11</sup> A random sub-sample of 115 of those schools were selected for the QAS tool data collection effort, with 55 initially randomly assigned to data collection firm enumerators and 60 assigned to MoETE supervisors. Due to limited availability of MoETE supervisors, 18 schools were reassigned to the data collection firm enumerators and five were not collected (due to their location and insufficient availability of data collection firm enumerators in that location).

Data were collected for up to three KG1 and three KG2 classes per school (randomly selected if more than three). A total of 333 classrooms were sampled across schools. Since there was often more than one teacher per class, this led to a sample of 434 teachers consenting to be interviewed and responding to both tools.<sup>12</sup> A random sample of four children per classroom was selected (1,332 children therefore should have been sampled) and 1,169 children consented and responded to both tools.<sup>13</sup> The data collection firm tried up to three times to reach parents, based on phone numbers provided by the school. For the parent data, there was substantial non-response (primarily that parents did not pick up, but some refusal when reached). Ultimately, 625 parents were reached and consented to be interviewed. Weights are used in all our analyses. The weights account for the original sampling design and non-response.<sup>14</sup>

# **_4.3 Outcomes_**

Our primary outcomes are the consistency of items or dimensions across the two tools, which are essentially an issue of measurement error. Reliability (internal consistency or test-retest) is a key issue driving potential measurement error (Bound, Brown, and Mathiowetz 2001). Some of the measures we observe are likely to be inherently variable and have modest internal consistency when measured at different times; for example, children may be worse at direct assessment items prior to snack or recess and perform better after snack or recess. Teachers may use different teaching strategies for different lessons, such that the results of observation tools would vary for different days and time periods. The CREDI tools, which assess ECD through parent reports,

> 9 Districts were randomly selected probability proportional to size (based on the number of schools), with replacement. Districts were drawn from within regions and based on the poverty status within a region (33% poor schools as cutoff).

> 10 If there are fewer than five schools within a district and strata, all schools were used (one to four).

> 11 Seven of the originally selected schools were unavailable (closed, in renovations, etc.) and random replacement schools, as much as possible from the same strata, were used.

> 12 The teacher consent rate was 87% for the diagnostic tool interview and 94% for the (shorter) QAS tool interview. 13 This is an overall response rate of 88%. Non-response was about 8% for each of the two tools and 12% overall, as children tended to refuse both more often if they refused at least one.

> 14 The weights account for the original sample design on the district and school levels, the sampling of classes (for class and teacher outcomes), and the random sampling of students (for student outcomes). Weights account for nonresponse and the number of observations that should have been included, for instance, the number of parents per class there should have been.

10