1. Center for Global Health & Development, Boston University, Boston, MA, USA
2. Health Economics and Epidemiology Research Office, Faculty of Health Sciences, Department of Internal Medicine, School of Clinical Medicine, University of the Witwatersrand, Johannesburg, South Africa
3. Clinical HIV Research Unit, Faculty of Health Sciences, Department of Internal Medicine, School of Clinical Medicine, University of the Witwatersrand, Johannesburg, South Africa
4. Right to Care, Johannesburg, South Africa
5. Department of Epidemiology, Boston University School of Public Health, Boston, MA, USA