1. Department of Preventive Medicine, Yonsei University Wonju College of Medicine, Wonju, Korea.
2. Department of Interanl Medicine, Yonsei University Wonju College of Medicine, Wonju, Korea.
3. Department of Surgery, Yonsei University Wonju College of Medicine, Wonju, Korea.
4. Department of Anesthesiology and Pain Medicine, Yonsei University Wonju College of Medicine, Wonju, Korea.