1. Department of Biostatistics, Virginia Commonwealth University , Richmond, VA 23298 , USA
2. Department of Health Behavior and Policy, Virginia Commonwealth University , Richmond, VA 23298 , USA
3. Department of Obstetrics and Gynecology, Duke University Medical Center , Durham, NC 27701 , USA
4. Department of Biological Sciences, Center for Human Health and the Environment, North Carolina State University , Raleigh, NC 27695 , USA
5. Environmental Science and Policy Division, Duke Global Health Institute and Nicholas School of the Environment , Durham, NC 27708 , USA
6. Department of Psychiatry and Behavioral Sciences, Duke University , Durham, NC 27701 , USA
7. Department of Epidemiology, University of North Carolina , Chapel Hill, NC 27599 , USA
8. Massey Cancer Center, Virginia Commonwealth University , Richmond, VA 23298 , USA