1. Wits Institute for Social and Economic Research (WISER),
University of the Witwatersrand, South Africa, poseld@wiser.wits.ac.za
2. MRC/Wits Rural Public Health and Health Transitions
Research Unit (Agincourt), School of Public Health, University of the Witwatersrand,
South Africa
3. Wits Institute for Social and Economic Research (WISER),
University of the Witwatersrand, South Africa, University of Hull, UK