1 Department of Psychiatry, University of Oxford, Oxford, UK; Centre for the Study of African Economies, Blavatnik School of Government and Economics Department, University of Oxford, Oxford, UK.
2 Department of Psychiatry, University of Oxford, Oxford, UK; MRC/Wits Rural Public Health and Health Transitions Research Unit (Agincourt), School of Public Health, Faculty of Health Sciences, University of Witwatersrand, Parktown, South Africa.
3 MRC/Wits Rural Public Health and Health Transitions Research Unit (Agincourt), School of Public Health, Faculty of Health Sciences, University of Witwatersrand, Parktown, South Africa; Department of Psychology, University of Cambridge, Cambridge, UK; Institute of Cognitive Neuroscience, University College London, London, UK.
4 MRC/Wits Rural Public Health and Health Transitions Research Unit (Agincourt), School of Public Health, Faculty of Health Sciences, University of Witwatersrand, Parktown, South Africa.
5 Centre for the Study of African Economies, Blavatnik School of Government and Economics Department, University of Oxford, Oxford, UK.
6 MRC/Wits Rural Public Health and Health Transitions Research Unit (Agincourt), School of Public Health, Faculty of Health Sciences, University of Witwatersrand, Parktown, South Africa; Department of Epidemiology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27516, USA. Electronic address: apettif@email.unc.edu.