1. Department of Health Behavior, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina.
2. Department of Psychology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina.
3. Lineberger Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina.
4. School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina.
5. Merck & Co, Inc., Kenilworth, New Jersey.