1. Department of Neurosurgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
2. Department of Medical Education and the Institute for Medical Humanities, Inje University College of Medicine, Busan, Korea
3. Department of Anesthesiology and Pain Medicine, Busan Paik Hospital, Inje University College of Medicine, Busan, Korea
4. Department of Pediatrics, Busan Paik Hospital, inje University College of Medicine, Busan, Korea