1. Department of Epidemiology & Biostatistics College of Human Medicine Michigan State University East Lansing Michigan USA
2. Carolina Population Center University of North Carolina, Chapel Hill Chapel Hill North Carolina USA
3. Department of Geography College of Arts and Sciences University of North Carolina, Chapel Hill Chapel Hill North Carolina USA
4. Lineberger Comprehensive Cancer Center School of Medicine University of North Carolina, Chapel Hill Chapel Hill North Carolina USA
5. Department of Sociology College of Arts and Sciences University of North Carolina, Chapel Hill Chapel Hill North Carolina USA
6. Department of Epidemiology Gillings School of Global Public Health University of North Carolina, Chapel Hill Chapel Hill North Carolina USA