[1] Osped Valduce, Gastroenterol Unit, Via Dante 10, I-22100 Como, Italy
[2] Univ Cattolica Sacro Cuore, Digest Endoscopy Unit, Rome, Italy
[3] Fdn Poliambulanza, Digest Endoscopy Unit, Brescia, Italy
[4] Shaare Zedek Med Ctr, Div Gastroenterol, Jerusalem, Israel
[5] Sana Klinikum, Dept Med 2, Offenbach, Germany
[6] Royal Free Hosp, Ctr Gastroenterol, Royal Free Unit Endoscopy, London, England
[7] UCL, London, England
[8] Royal Infirm Edinburgh NHS Trust, Endoscopy Unit, Edinburgh, Midlothian, Scotland
[9] South Tyneside Hosp, Dept Gastroenterol, South Shields, England
[10] Univ Munster, Dept Med B, Munster, Germany
[11] Hosp Navarra, Dept Gastroenterol, Pamplona, Spain
[12] Georges Pompidou European Hosp, AP HP, Dept Gastroenterol & Digest Endoscopy, Paris, France
[13] Acad Med Ctr, Dept Gastroenterol & Hepatol, Amsterdam, Netherlands
[14] Nuovo Regina Margherita Hosp, Endoscopy Unit, Rome, Italy
[15] Azienda Osped Univ, Citta Salute & Sci, Div Gastroenterol U, Turin, Italy