1. Medical Research Council/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
2. Institut d’analyse du changement dans l’histoire et les sociétés contemporaines (IACCHOS), Centre De Recherches En Démographie, Université Catholique De Louvain, Louvain-la-Neuve, Belgium
3. Department of Science and Innovation/South African Medical Research Council, South African Population Research Infrastructure Network, South Africa