1. New England Research Institutes, Watertown, MA 02472
2. Department of Nutrition and Department of Epidemiology, Harvard School of Public Health, Boston, MA 02115
3. Department of Medicine, Channing Laboratory, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115
4. Department of Urology, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611