1. Department of Family Medicine, University of North Carolina at Chapel Hill , Chapel Hill, NC 27599 , USA
2. Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill , Chapel Hill, NC , USA
3. Department of Health Law, Policy, and Management, Boston University School of Public Health , Boston, MA , USA
4. Department of Psychology and Neuroscience, University of North Carolina at Chapel Hill , Chapel Hill, NC , USA
5. Department of Health Promotion, Education, and Behavior, Arnold School of Public Health, University of South Carolina , Columbia, SC , USA