1. Department of Epidemiology, University of Kentucky, Lexington, KY
2. Department of Epidemiology, University of Alabama at Birmingham, Birmingham, AL
3. Department of Population Health Sciences, Duke University School of Medicine, Durham, NC
4. Markey Cancer Center, University of Kentucky, Lexington, KY
5. Division of Preventive Medicine, University of Alabama at Birmingham, Birmingham, AL
6. Cancer Prevention and Control Program, Lombardi Comprehensive Cancer Center, Georgetown University Medical Center, Washington, DC