1. Epidemiology Branch, Division of Intramural Population Health Research
2. Program of Reproductive and Adult Endocrinology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, NIH, Department of Health and Human Services, Bethesda, MD
3. Department of Epidemiology and Environmental Health, University at Buffalo, Buffalo, NY
4. Sophie Davis School of Biomedical Education, City College of New York, New York, NY