[1] Capital Med Univ, Xuanwu Hosp, Evidence Based Med Ctr, 45 Changchun St, Beijing 100053, Peoples R China
[2] Minist Educ, Key Lab Neurodegenerat Dis, Beijing, Peoples R China
[3] Capital Med Univ, Med Affairs Dept, Affiliated Beijing Friendship Hosp, Beijing, Peoples R China
[4] Capital Med Univ, Xuanwu Hosp, Dept Vasc Ultrasonog, Beijing, Peoples R China
[5] Capital Med Univ, Geriatr Dept, Beijing, Peoples R China