1. Departments of Medicine and Obstetrics & Gynecology, University of Michigan, Ann Arbor, MI
2. Department of Medicine, University of Vermont, Burlington, VT
3. Division of Preventive Medicine, University of Alabama at Birmingham, AL
4. Department of Epidemiology, University of Michigan School of Public Health, Ann Arbor, MI
5. Department of Epidemiology, University of Alabama at Birmingham, AL
6. University of Cincinnati, OH