1. Korea Health Insurance Review Agency, Seoul, Korea
2. Department of Preventive Medicine, College of Medicine, Korea University, Seoul, Korea
3. Department of Thoracic and Cardiovascular Surgery, College of Medicine, Chungbuk National University, Cheongju, Korea
4. Department of Urology, Samsung Medical Centre, Sungkyunkwan University School of Medicine, Seoul, Korea
5. Department of Anatomy, College of Medicine, Ewha Womans University, Seoul, Korea