1. Department of Epidemiology, West Virginia University, Morgantown, West Virginia.
2. Department of Public Health Sciences, University of Virginia, Charlottesville, Virginia.
3. School of Nursing, University of Virginia, Charlottesville, Virginia.
4. School of Medicine, University of Virginia, Charlottesville, Virginia.
5. School of Public Health, West Virginia University, Morgantown, West Virginia.
6. Department of Pediatrics, University of Virginia, Charlottesville, Virginia.
7. Institute of Women's Health, Virginia Commonwealth University, Richmond, Virginia.
8. Department of Pediatrics, Virginia Commonwealth University, Richmond, Virginia.