1. Department of Environmental Health, Rollins School of Public Health, Emory University; Clifton Road, Atlanta, Georgia, USA
2. Department of Health Behavior and Biological Science, School of Nursing, University of Michigan, Ann Arbor, Michigan, USA
3. The Center for Sexuality and Health Disparities, University of Michigan, Ann Arbor, Michigan, USA
4. Department of Epidemiology, Rollins School of Public Health, Emory University, Clifton Road, Atlanta, Georgia, USA