[1] Univ North Carolina Chapel Hill, Div Infect Dis, Dept Med, Sch Med, 130 Mason Farm Rd,CB 7030, Chapel Hill, NC 27599 USA
[2] Univ North Carolina Chapel Hill, Div Gen Internal Med & Clin Epidemiol, Sch Med, Chapel Hill, NC USA
[3] Univ North Carolina Chapel Hill, Dept Hlth Behav, Gillings Sch Global Publ Hlth, Chapel Hill, NC USA
[4] Univ Connecticut, Hlth Dispar Inst, Hartford, CT 06112 USA
[5] Univ North Carolina Chapel Hill, Ctr AIDS Res, Sch Med, Chapel Hill, NC 27599 USA