1. Department of Physical Medicine and Rehabilitation, National Health Insurance Service Ilsan Hospital, Goyang, Korea.
2. Yonsei University Graduate School of Medicine, Seoul, Korea.
3. Rehabilitation Institute of Neuromuscular Disease, Yonsei University College of Medicine, Seoul, Korea.
4. Department of Rehabilitation Medicine, Gangnam Severance Hospital, Yonsei University College of Medicine, Seoul, Korea.