1. Department of Neurology, Seoul National University Bundang Hospital, Seoul National University College of Medicine, Seongnam, Korea.
2. Department of Neurology, Korea University Guro Hospital, Seoul, Korea.
3. Department of Neurology, Inje University Ilsan Paik Hospital, Goyang, Korea.
4. Department of Neurology, Uijeongbu Eulji Medical Center, Eulji University, Uijeongbu, Korea.
5. Department of Neurology, Soonchunhyang University Hospital, Soonchunhyang University College of Medicine, Seoul, Korea.
6. Department of Neurology, Dong-A University Hospital, Dong-A University College of Medicine, Busan, Korea.
7. Clinical Research Center, Asan Institute for Life Sciences, Asan Medical Center, Seoul, Korea.
8. Department of Biostatistics, Korea University College of Medicine, Seoul, Korea.
9. Health Insurance Review and Assessment Service, Wonju, Korea.
10. Department of Neurology, Gyeonggi Provincial Medical Center Icheon Hospital, Icheon, Korea.
11. Davee Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, Illinois.