1. South African Medical Research Council; South African Cochrane Centre; PO Box 19070 Tygerberg Cape Town Western Cape South Africa 7505
2. Stellenbosch University; Centre for Evidence-based Health Care, Faculty of Medicine and Health Sciences; Francie v Zyl Tygerberg Cape Town South Africa
3. University of Washington; Department of Global Health; 901 Boren Avenue, Suite 1100 Seattle WA USA 98104