1. Division of Gastroenterology, Tohoku University Graduate School of Medicine, Sendai, Japan
2. R & D Division of Career Education for Medical Professionals, Medical Education Center, Jichi Medical University, Shimotsuke, Japan
3. Graduate Medical Education Center, Tohoku University Hospital, Sendai, Japan
4. Division of Gastroenterology, McMaster University Faculty of Health Sciences, Hamilton, Canada
5. Faculty of Medical Science and Welfare, Tohoku Bunka Gakuen University, Sendai, Japan