[1] Karolinska Inst, Dept Publ Hlth Sci, S-17177 Stockholm, Sweden
[2] Shanghai Jiao Tong Univ, Sch Med, Ruijin Hosp, Dept Neurol, Shanghai 200030, Peoples R China
[3] Shanghai Jiao Tong Univ, Sch Publ Hlth, Shanghai 200030, Peoples R China
[4] Shanghai Jiao Tong Univ, Sch Med, Xinhua Hosp, Dept Neurol, Shanghai 200030, Peoples R China
[5] Shanghai Jiao Tong Univ, Sch Med, Shanghai Peoples Hosp 9, Dept Neurol, Shanghai 200030, Peoples R China
[6] Second Mil Med Univ, Changzheng Hosp, Dept Neurol, Shanghai, Peoples R China
[7] Shanghai Jiao Tong Univ, Sch Med, Shanghai Peoples Hosp 6, Dept Neurol, Shanghai 200030, Peoples R China