1. Department of Gastroenterology and Hepatology Okayama University Hospital Okayama Japan
2. Department of Internal Medicine Okayama Saiseikai General Hospital Okayama Japan
3. Departments of Internal Medicine Fukuyama City Hospital Hiroshima Japan
4. Department of Gastroenterology Iwakuni Medical Center Hiroshima Japan
5. Department of Gastroenterology Tsuyama Central Hospital Okayama Japan
6. Department of Gastroenterology, National Hospital Organization Okayama Medical Center Okayama Japan