1. Department of Emergency Medicine, Korea University College of Medicine, Ansan Hospital, Ansan, Korea.
2. Department of Physical Therapy, Kyungnam University, Changwon, Korea.
3. Department of Neurosurgery, Kyung Hee University College of Medicine, Kyung Hee University Hospital at Gangdong, Seoul, Korea.
4. Department of Anesthesiology and Pain Medicine, Kyung Hee University College of Medicine, Kyung Hee University Hospital at Gangdong, Seoul, Korea.