[1] Shandong Univ, Sch Publ Hlth, Dept Epidemiol, 44 Wenhuaxi Rd, Jinan 250012, Peoples R China
[2] Univ Lausanne Hosp, Inst Social & Prevent Med, Lausanne, Switzerland
[3] Ewha Womans Univ, Sch Med, Dept Pediat, Mokdong Hosp, Seoul, South Korea
[4] Capital Inst Pediat, Dept Growth & Dev, Beijing, Peoples R China
[5] McGill Univ, Dept Epidemiol Biostat & Occupat Hlth, Montreal, PQ, Canada
[6] Shandong Univ, Sch Publ Hlth, Dept Biostat, Jinan, Peoples R China
[7] Tulane Univ, Dept Epidemiol, New Orleans, LA 70118 USA
[8] Shandong Univ, Sch Publ Hlth, Dept Nutr & Food Hyg, Jinan, Peoples R China