1. Department of Emergency Medicine, George Washington University School of Medicine & Health Sciences, Washington, District of Columbia, USA.
2. Department of Emergency Medicine, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA.
3. Department of Urology, George Washington University School of Medicine & Health Sciences, Washington, District of Columbia, USA.
4. The George Washington University Biostatistics Center, Rockville, Maryland, USA.
5. National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland, USA.
6. Department of Urology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA.