[1] China Med Univ, Sch Publ Hlth, Dept Biostat & Epidemiol, Shenyang, Liaoning, Peoples R China
[2] China Med Univ, Sch Publ Hlth, Dept Occupat & Environm Hlth, Shenyang, Liaoning, Peoples R China
[3] St Louis Univ, Sch Publ Hlth, Dept Epidemiol, St Louis, MO 63103 USA
[4] Shenyang Environm Monitoring Ctr, Dept Ambient Air Pollut Monitor, Shenyang, Liaoning, Peoples R China
[5] Guangdong Prov Ctr Dis Control & Prevent, Guangdong Prov Inst Publ Hlth, Guangzhou, Guangdong, Peoples R China
[6] St Louis Univ, Sch Publ Hlth, Dept Biostat, St Louis, MO 63103 USA
[7] St Louis Univ, Sch Publ Hlth, Dept Environm & Occupat Hlth, St Louis, MO 63103 USA