1. Cochrane South Africa, South African Medical Research Council, Cape Town 7505, South Africa
2. School of Public Health and Family Medicine, Faculty of Health Sciences, University of Cape Town, Cape Town 7935, South Africa
3. Department of Global Health, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town 7505, South Africa
4. HIV and Other Infectious Diseases Research Unit, South African Medical Research Council, Durban 4091, South Africa
5. Vaccine Preventable Diseases Programme, Universal Health Coverage/Communicable and Non-Communicable Diseases Cluster, World Health Organization Regional Office for Africa, Brazzaville P.O. Box 06, Congo