1. Department of Science and Innovation, South African Population Research Infrastructure Network (SAPRIN), South African Medical Research Council, South Africa
2. MRC/Wits Rural Public Health and Health Transitions Research Unit, School of Public Health, University of the Witwatersrand, Johannesburg, South Africa
3. DIMAMO Population Health Research Centre, University of Limpopo, Turfloop, South Africa
4. Africa Health Research Institute, Mtubatuba, South Africa