1. Department of Medicine, Division of General Internal Medicine, University of Iowa Carver College of Medicine, Iowa City, Iowa.
2. Department of Biostatistics and Informatics, Colorado School of Public Health, University of Colorado School of Medicine, Aurora, Colorado.
3. Department of Obstetrics and Gynecology, University of Colorado School of Medicine, Aurora, Colorado.
4. Department of Medicine, Division of General Internal Medicine and Center for Women's Health Research, University of Colorado School of Medicine, Aurora, Colorado.