1. Departments of Preventive Medicine, School of Medicine, Kyung Hee University
2. Total healthcare center, Kangbuk Samsung Hospital, Sungkyunkwan University, School of medicine
3. Department of Occupational and Environment Medicine, College of Medicine, Ewha Womans University
4. Department of Biomedical Science, Graduate School, Kyung Hee University
5. Division of Gastroenterology and Hepatology, Department of Internal Medicine, School of Medicine, Kyung Hee University
6. Department of Anesthesiology and Pain Medicine, Kyung Hee University
7. Department of Preventive Medicine, Graduate School, Kyung Hee University
8. Departments of Occupational and Environmental Medicine, School of Medicine, Kyung Hee University