1. Department of Epidemiology and Health Statistics, School of Public Health Fujian Medical University Fuzhou China
2. Fujian Key Laboratory of Oral Diseases, Department of Periodontology, School and Hospital of Stomatology Fujian Medical University Fuzhou China
3. Laboratory Center, The Major Subject of Environment and Health of Fujian Key Universities, School of Public Health Fujian Medical University Fuzhou China
4. Clinical Research Unit, The Second Affiliated Hospital Fujian Medical University Quanzhou China