[1] Nuovo Regina Margherita Hosp, Digest Endoscopy, Via E Morosini 30, I-00153 Rome, Italy
[2] Univ Oxford, Translat Gastroenterol Unit, John Radcliffe Hosp, Oxford, England
[3] Oxford NIHR Biomed Res Ctr, Oxford, England
[4] Valduce Hosp, Como, Italy
[5] Fdn Poliambulanza, Digest Endoscopy Unit, Brescia, Italy
[6] Gastroenterol Unit, Bobigny, France
[7] Katholieke Univ Leuven, Univ Hosp Leuven, Dept Gastroenterol & Hepatol, Leuven, Belgium
[8] Univ Oslo, Inst Hlth & Soc, Dept Transplantat Med, Oslo Univ Hosp, Oslo, Norway
[9] Univ Amsterdam, Med Ctr, Dept Gastroenterol & Hepatol, Amsterdam, Netherlands
[10] Univ Porto, Fac Med, CIDES CINTESIS, Porto, Portugal
[11] Univ Bologna, S Orsola Malpighi Hosp, Gastroenterol Unit, Dept Med & Surg Sci, Bologna, Italy
[12] Technion Israel Inst Technol, Inst Gastroenterol & Hepatol Emek Med Ctr Afula, Israel Rappaport Fac Med, Haifa, Israel
[13] Hosp Gen Univ Alicante, Serv Med Digest, Inst Invest Sanitaria ISABIAL, Alicante, Spain
[14] Ctr Postgrad Med Educ, Dept Gastroenterol Hepatol & Oncol, Warsaw, Poland
[15] Univ Barcelona, Gastroenterol Dept, Hosp Clin, Inst Malalties Digest & Metabol, Barcelona, Spain
[16] Athens Univ, Dept Internal Med & Res Inst 2, Hepatogastroenterol Unit, Athens, Greece
[17] Sapienza Univ Rome, St Andrea Hosp, Digest Dis Unit, Rome, Italy
[18] Gedyt Endoscopy Ctr, Buenos Aires, DF, Argentina
[19] Med Univ Vienna, Dept Internal Med 3,Qual Assurance Working Grp, Div Gastroenterol & Hepatol, Austrian Soc Gastroenterol & Hepatol, Vienna, Austria