Author Contributions: Dr Hebel had full access to all the data in the study and takes responsibility for the integrity of the data and accuracy of the data analysis. Study concept and design: Hebel, Middleton, and Turchin. Acquisition of data: Hebel and Turchin. Analysis and interpretation of data: Hebel, Shubina, and Turchin. Drafting of the manuscript: Hebel. Critical revision of the manuscript for important intellectual content: Hebel, Middleton, Shubina, and Turchin. Statistical analysis: Hebel and Shubina. Administrative, technical, and material support: Hebel and Middleton. Study supervision: Middleton and Turchin.
Financial Disclosure: None reported.
Funding/Support: This research was funded in part by scholarship grants from the Fulbright Commission–Institute of International Education (Dr Hebel) and the National Commission for Scientific and Technological Research, Chile.