1. Department of Surgery, The Catholic University of Korea College of Medicine, Korea
2. Department of Surgery, Chung-Ang University College of Medicine, Seoul, Korea
3. Department of Surgery, Ajou University School of Medicine, Suwon, Korea
4. Department of Surgery, Keimyung University School of Medicine, Daegu, Korea
5. Department of Surgery, Kosin University College of Medicine, Busan, Korea
6. Department of Surgery, Yonsei University College of Medicine, Seoul, Korea