1. Department of Chemical Pathology National Health Laboratory Service University of the Witwatersrand Faculty of Health Sciences Johannesburg South Africa
2. Department of Internal Medicine Steve Biko Academic Hospital University of Pretoria Pretoria South Africa
3. Department of Diabetes and Endocrinology Nelson R. Mandela School of Medicine University of KwaZulu‐Natal Durban South Africa
4. Private Practice Life Hospital Groenkloof Pretoria South Africa