Joel Wackerbarth1, Hiten D Patel2, Deepak R Singh3. 1. Epidemiology and Biostatistics, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA; University of Washington School of Medicine, Seattle, WA, USA; James Buchanan Brady Urological Institute, Johns Hopkins Medical Institutions, Baltimore, MD, USA. Electronic address: joel01@uw.edu. 2. James Buchanan Brady Urological Institute, Johns Hopkins Medical Institutions, Baltimore, MD, USA. 3. Department of Surgery, Kathmandu Medical College, Kathmandu Nepal.