1. Department of Urology, David Geffen School of Medicine and School of Public Health, University of California, Los Angeles, Los Angeles
2. Department of Surgery, Division of Urology, University of British Columbia, Vancouver, British Columbia, Canada
3. Department of Family and Community Medicine, University of California, San Francisco School of Medicine, San Francisco, California
4. Department of Health Services, David Geffen School of Medicine and School of Public Health, University of California, Los Angeles, Los Angeles