[1] Univ Free State, Dept Family Med, Fac Hlth Sci, Bloemfontein, South Africa
[2] Robert Mangaliso Sobukwe Hosp, Northern Cape Dept Hlth, Kimberley, South Africa
[3] Univ Cape Town, Sch Publ Hlth & Family Med, Div Family Med, Fac Hlth Sci, Cape Town, South Africa