1. Public Health Medicine, University of KwaZulu-Natal, Durban, South Africa
2. Faculty of Commerce, University of the Witwatersrand, Johannesburg, South Africa
3. Steno Diabetes Center Copenhagen, Gentofte, Denmark, and MRC Developmental Pathways for Health Research Unit, University of the Witwatersrand, Johannesburg, South Africa
4. Health Systems Trust, Westville, South Africa
5. School of Life Sciences, University of KwaZulu-Natal, Durban, South Africa
6. Department of Genetics, Evolution and Environment, University College London, London, UK
7. School of Public Health, University of the Witwatersrand, Johannesburg, South Africa