1. Statistics Committee of the Korean Association of Thyroid and Endocrine Surgeons, Seoul, Korea.
2. Department of Surgery, Division of Breast and Endocrine Surgery, Korea University College of Medicine, Korea University Anam Hospital, Seoul, Korea.
3. Department of Surgery, Gachon University College of Medicine, Gil Medical Center, Incheon, Korea.
4. Division of Endocrine Surgery, Department of Surgery, Chung-Ang University College of Medicine, Seoul, Korea.
5. Department of Surgery, Konkuk University Medical Center, Konkuk University School of Medicine, Seoul, Korea.
6. Research Institute of Medical Science, Konkuk University School of Medicine, Seoul, Korea.