1. Botswana—Harvard School of Public Health AIDS Initiative Partnership, Gaborone, Botswana
2. Harvard School of Public Health, Department of Immunology & Infectious Diseases and the Harvard School of Public Health AIDS Initiative, Boston, MA, USA
3. National AIDS Coordinating Agency, Gaborone, Botswana
4. University of Botswana, Gaborone, Botswana; Harvard School of Public Health, Department of Biostatistics, Boston, MA, USA
5. Botswana—Harvard School of Public Health AIDS Initiative Partnership, Gaborone, Botswana; Harvard School of Public Health, Department of Biostatistics, Boston, MA, USA
6. Harvard School of Public Health AIDS Initiative, Boston, MA, USA