1. Division of Epidemiology & Biostatistics, School of Public Health & Family Medicine, University of Cape Town, Cape Town, South Africa
2. Centre for Infectious Disease Epidemiology & Research, School of Public Health & Family Medicine, University of Cape Town, Cape Town, South Africa
3. HIV Center for Clinical and Behavioral Studies, New York State Psychiatric Institute, Columbia University, New York, NY, USA
4. ICAP, Columbia University, Mailman School of Public Health, New York, NY, USA
5. College of Physicians & Surgeons, Columbia University, New York, NY, USA