1 Department of Rehabilitation Medicine, Pusan National University Yangsan Hospital, Pusan National University School of Medicine, Yangsan, Korea.
2 Department of Rehabilitation Medicine, Pusan National University Hospital, Pusan National University School of Medicine, Busan, Korea.
3 Department of Rehabilitation Medicine, Pusan National University Hospital, Pusan National University School of Medicine, Busan, Korea.; Biomedical Research Institute, Pusan National University Hospital, Busan, Korea.