1. Graduate School, Ewha Womans University, Seoul, Korea
2. Division of Nursing, Gangnam Severance Hospital, Yonsei University College of Medicine, Seoul, Korea
3. Thyroid Cancer Center, Gangnam Severance Hospital, Yonsei University College of Medicine, Seoul, Korea
4. Department of Surgery, Gangnam Severance Hospital, Yonsei University College of Medicine, Seoul, Korea