1. Department of Public Health, College of Public Health, and College of Medicine, China Medical University , Taichung, Taiwan
2. Department of Family Medicine, China Medical University Hospital , Taichung, Taiwan
3. College of Medicine, Tzu Chi University , Hualien, Taiwan
4. Division of Hepatogastroenterology, Department of Internal Medicine, Taichung Tzu Chi Hospital , Taichung, Taiwan
5. Department of Occupational Safety and Health, College of Public Health, China Medical University , Taichung, Taiwan
6. College of Medicine, China Medical University , Taichung, Taiwan