1. Department of Gastroenterology and Metabology, Ehime University Graduate School of Medicine, Japan
2. Department of Epidemiology and Preventive Medicine, Ehime University Graduate School of Medicine, Japan
3. Epidemiology and Medical Statistics Unit, Translational Research Center, Ehime University Hospital, Japan
4. Department of Community Medicine, Ehime University Graduate School of Medicine, Japan
5. Ehime General Health Care Association, Japan