[1] Fujita Hlth Univ, Dept Gastroenterol, Sch Med, Toyoake, Aichi, Japan
[2] Nippon Med Sch, Dept Gastroenterol, Grad Sch Med, Tokyo, Japan
[3] Nagoya Univ, Dept Gastroenterol & Hepatol, Grad Sch Med, Nagoya, Aichi, Japan
[4] Univ Tokyo, Dept Gastroenterol, Grad Sch Med, Tokyo, Japan
[5] Hiroshima Univ Hosp, Dept Endoscopy, Hiroshima, Japan
[6] Kyushu Univ, Grad Sch Med Sci, Dept Med & Clin Sci, Fukuoka, Fukuoka, Japan
[7] Yokohama City Univ, Div Gastroenterol & Hepatol, Sch Med, Yokohama, Kanagawa, Japan
[8] Iwate Med Univ, Div Gastroenterol, Dept Internal Med, Morioka, Iwate, Japan
[9] NPO Drug Safety Res Unit Japan, Tokyo, Japan