[1] Univ Cape Town, Fac Hlth Sci, Inst Infect Dis & Mol Med, Desmond Tutu HIV Ctr, ZA-7925 Cape Town, South Africa
[2] London Sch Hyg & Trop Med, Dept Clin Res, Fac Infect & Trop Dis, London WC1, England
[3] Massachusetts Gen Hosp, Dept Med, Med Practice Evaluat Ctr, Boston, MA 02114 USA
[4] Tufts Med Ctr, Inst Clin Res & Hlth Policy Studies, Boston, MA USA
[5] Tufts Univ, Tufts Clin & Translat Sci Inst, Boston, MA 02111 USA
[6] Univ Cape Town, Fac Hlth Sci, Dept Med, ZA-7925 Cape Town, South Africa
[7] Massachusetts Gen Hosp, Div Gen Med, Boston, MA 02114 USA
[8] Massachusetts Gen Hosp, Div Infect Dis, Boston, MA 02114 USA
[9] Brigham & Womens Hosp, Div Infect Dis, Boston, MA 02115 USA
[10] Harvard Univ, Ctr AIDS Res CFAR, Boston, MA 02115 USA
[11] Harvard Univ, Sch Publ Hlth, Dept Hlth Policy & Management, Boston, MA 02115 USA