[1] Soonchunhyang Univ, Coll Med, Dept Neurol, Seoul 140743, South Korea
[2] Seoul Natl Univ, Bundang Hosp, Dept Neurol, Songnam, South Korea
[3] Soonchunhyang Univ, Coll Med, Dept Biostat, Seoul, South Korea
[4] Soonchunhyang Univ, Sch Med, Kangbuk Samsung Hosp, Dept Lab Med, Seoul, South Korea