The inquiry, which acknowledged that it relied in part on incomplete school records, found only 31 grave sites and did not substantiate or refute claims of abuse.
The skill control variables take the form of the share of natives who hold a degree, have completed school, have incomplete schooling, or are still in full-time education.
If education was completed before the age of 16, it is taken to proxy incomplete schooling; and if education was completed between the ages of 16 and less than 21, it is taken to imply that schooling has been completed (see Saleheen and Shadforth 2006 for details).
The following variables were considered as potential confounders in the analyses: gender, age (continuous in the multivariate analyses) and current educational level (undergraduate school, high school, elementary school, incomplete elementary school).
Formal education was reclassified in completed or incomplete elementary school, middle school, high school and college.
Only one third (36 %) had completed primary school and a quarter (27 %) had no formal schooling or incomplete primary school.
The following socio-demographic variables were considered in the analysis: gender; age range (≤13, 14, 15, ≥16 years); ethnicity/skin colour (white, black, brown or mixed-race, Asian, native Brazilian Indian); mother's educational level (incomplete middle school, complete middle school, complete high-school, complete higher education).
Educational level achieved by subjects was classified in 4 categories: illiterate, incomplete primary school, complete primary school (education through 13-14 years of age), and high school (through 17-18 years), or higher education.
No formal education, 2. Incomplete primary school, 3. Complete primary school, 4. Incomplete secondary school: technical/vocational type, 5. Complete secondary school: technical/vocational type, 6. Incomplete secondary: university-preparatory type, 7. Complete secondary: university-preparatory type, 8. Some university-level education, without degree, 9. University-level education, with degree".
Maternal education (incomplete compulsory school; 9 years compulsory school; upper secondary school; post secondary; postgraduate) was obtained from the 1990 census.
