1. Department of Urology, University of California-San Francisco, San Francisco, California
2. Department of Surgery, King Abdulaziz University, Rabigh, Saudi Arabia
3. Division of Public Health Sciences, Department of Surgery, Washington University, St. Louis, Missouri
4. Department of Urology, Stanford University School of Medicine, Stanford, California
5. Department of Surgery, Dell Medical School, University of Texas, Austin, Texas
6. Department of Biostatistics and Epidemiology, University of California-San Francisco, San Francisco, California