1. 1Department of Health Policy and Management, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, North Carolina.
2. 2Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill, North Carolina.
3. 3Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, North Carolina.
4. 4Department of Biostatistics, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, North Carolina.
5. 5Center for Biostatistics in AIDS Research, Harvard T.H. Chan School of Public Health, Boston, Massachusetts.
6. 6Department of Health Behavior, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, North Carolina.