[1] Cent South Univ, Xiangya Sch Publ Hlth, Dept Epidemiol & Biostat, Changsha, Hunan, Peoples R China
[2] Cent South Univ, Xiangya Nursing Sch, Changsha, Hunan, Peoples R China
[3] Cent South Univ, Xiangya Hosp, Dept Geriatr, Changsha, Hunan, Peoples R China
[4] Cent South Univ, Xiangya Hosp, Natl Clin Res Ctr Geriatr Disorders, Changsha, Hunan, Peoples R China
[5] Hunan Prov Key Lab Clin Epidemiol, Changsha, Peoples R China
[6] Cent South Univ, Xiangya Sch Publ Hlth, 5-F 238,Shang ma yuan ling Alley, Changsha, Hunan, Peoples R China