1. Department of Physical Medicine & Rehabilitation, Korea University Guro Hospital, Seoul, Republic of Korea
2. Department of Rehabilitation Medicine, Bundang Jesaeng General Hospital, Gyeonggi-do, Republic of Korea
3. Department of Statistics and Actuarial Science, Soongsil University, Seoul, Republic of Korea
4. Department and Research Institute of Rehabilitation Medicine, Yonsei University College of Medicine, Seoul, Republic of Korea