1. Department of Epidemiology and Health Statistics; Qingdao University Medical College; Qingdao Shandong China
2. Qingdao Municipal Center for Disease Control and Prevention; Qingdao Institute of Preventive Medicine; Qingdao Shandong China
3. Unit of Human Genetics, Department of Clinical Research; University of Southern Denmark; Odense Denmark
4. Epidemiology, Biostatistics and Biodemography, Department of Public Health; University of Southern Denmark; Odense Denmark