Chin-Feng Lin1,2,3
, Jung-Der Wang1
, Ping-Ho Chen4
, Shun-Jen Chang5
, Yi-Hsin Yang6,7
and Ying-Chin Ko4,5 
1
Institute of Occupational Medicine and Industrial Hygiene, National Taiwan University, College of Public Health and Department of Internal Medicine, National Taiwan University Hospital, Taipei, Taiwan
2
Department of Health, Executive Yuan, Taiwan
3
Department of Public Health, Taipei Medical University, Taipei, Taiwan
4
Division of Environmental Health and Occupational Medicine, National Health Research Institutes, Kaohsiung 807, Taiwan
5
Department of Public Health, Faculty of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan
6
Graduate Institute of Oral Health Sciences, College of Dental Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan
7
Statistical Analysis Laboratory, Department of Clinical Research, Kaohsiung Medical University Chung-Ho Memorial Hospital, Taiwan