1. Department of Urology, Gachon University Gil Medical Center, Gachon University School of Medicine, Incheon, Korea.
2. Department of Adult Health Nursing, Seoul Women's College of Nursing, Seoul, Korea.
3. Department of Urology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
4. Department of Physiology, Kyung Hee University School of Medicine, Seoul, Korea.