About the Authors

Samuel J. Clark

Affiliations Department of Sociology, University of Washington, Seattle, Washington, United States of America, Institute of Behavioral Science, University of Colorado at Boulder, Boulder, Colorado, United States of America, MRC/Wits Rural Public Health and Health Transitions Research Unit (Agincourt), School of Public Health, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa

Brian Houle

brian.houle@anu.edu.au

Affiliations Institute of Behavioral Science, University of Colorado at Boulder, Boulder, Colorado, United States of America, MRC/Wits Rural Public Health and Health Transitions Research Unit (Agincourt), School of Public Health, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa, Australian Demographic and Social Research Institute, The Australian National University, Canberra, Australia

Competing Interests

The authors have declared that no competing interests exist.

Author Contributions

Conceived and designed the experiments: SC BH. Analyzed the data: SC BH. Wrote the paper: SC BH.