[1] Peking Univ, China Ctr Hlth Dev Studies, Beijing, Peoples R China
[2] George Washington Univ, Dept Epidemiol, Milken Inst Sch Publ Hlth, Washington, DC USA
[3] Queens Univ Belfast, Ctr Publ Hlth, Belfast, Antrim, North Ireland
[4] Sun Yat Sen Univ, Zhongshan Ophthalm Ctr, Guangzhou, Peoples R China
[5] Icahn Sch Med Mt Sinai, Dept Populat Hlth Sci & Policy, New York, NY 10029 USA
[6] Clemson Univ, Dept Publ Hlth Sci, Coll Behav Social & Hlth Sci, Clemson, SC 29631 USA
[7] Univ Georgia, Coll Publ Hlth, Dept Hlth Policy & Management, 205D Wright Hall,Hlth Sci Campus,100 Foster Rd, Athens, GA 30602 USA