[1] Univ Ulsan, Coll Med, Gangneung Asan Hosp, Dept Internal Med, Kangnung, South Korea
[2] Inje Univ, Coll Med, Dept Internal Med, Div Gastroenterol, Seoul, South Korea
[3] Soonchunhyang Univ, Coll Med, Dept Gastroenterol, Bucheon, South Korea
[4] Yonsei Univ, Wonju Coll Med, Dept Gastroenterol, Wonju, South Korea
[5] Gachon Univ, Gil Med Ctr, Dept Gastroenterol, Incheon, South Korea
[6] Kyung Hee Univ, Sch Med, Dept Gastroenterol, Seoul, South Korea
[7] Ewha Womans Univ, Sch Med, Dept Gastroenterol, Seoul, South Korea
[8] Wonkwang Univ, Sch Med, Dept Gastroenterol, Iksan, South Korea
[9] Pusan Natl Univ, Sch Med, Dept Gastroenterol, Busan, South Korea
[10] Sungkyunkwan Univ, Sch Med, Kangbuk Samsung Hosp, Dept Gastroenterol, Seoul, South Korea
[11] Kyungpook Natl Univ, Sch Med, Dept Gastroenterol, Daegu, South Korea
[12] Chung Ang Univ, Coll Med, Dept Gastroenterol, Seoul, South Korea
[13] Konyang Univ, Coll Med, Dept Gastroenterol, Daejeon, South Korea
[14] Catholic Univ Korea, Coll Med, Dept Gastroenterol, Seoul, South Korea
[15] Yonsei Univ, Coll Med, Dept Internal Med, Div Gastroenterol, Seoul, South Korea
[16] Seoul Natl Univ, Coll Med, Dept Gastroenterol, Seoul, South Korea
[17] Yeungnam Univ, Coll Med, Dept Gastroenterol, Daegu, South Korea
[18] Inje Univ, Coll Med, Dept Internal Med, Div Gastroenterol, Busan, South Korea
[19] Univ Ulsan, Coll Med, Asan Med Ctr, Dept Gastroenterol, Seoul, South Korea