[1] Qingdao Ctr Dis Control & Prevent, Qingdao 266033, Peoples R China
[2] Univ Helsinki, Hjelt Inst, Dept Publ Hlth, Helsinki, Finland
[3] Qingdao Univ, Coll Med, Dept Publ Hlth, Qingdao 266071, Peoples R China
[4] Jiaonan Ctr Dis Control & Prevent, Qingdao, Peoples R China
[5] Univ So Denmark, Inst Publ Hlth, Odense, Denmark
[6] Odense Univ Hosp, Dept Clin Genet, DK-5000 Odense, Denmark
[7] Shandong Univ, Dept Publ Hlth, Jinan 250100, Peoples R China