[1] Univ Freiburg, Acad Teaching Hosp, Dept Med & Gastroenterol, Evangelisches Diakoniekrankenhaus Freiburg, Wirthstr 11, D- 79110 Freiburg, Germany
[2] Univ Hosp Augsburg, Dept Gastroenterol, Augsburg, Germany
[3] Univ Freiburg, Fac Med, Med Ctr, Dept Med 2, Freiburg, Germany
[4] Univ Tubingen, Acad Teaching Hosp, Robert Bosch Krankenhaus, Dept Gastroenterol Hepatol & Endocrinol, Stuttgart, Germany
[5] Heidelberg Univ, Mannheim Univ Hosp, Cent Interdisciplinary Endoscopy Dept, Mannheim, Germany
[6] Univ Hosp Wurzburg, Dept Med 2, Wurzburg, Germany
[7] Rheinisch Westfalische TH Aachen, Acad Teaching Hosp, Dept Gastroenterol, Rhein Maas Klinikum Wurselen, Wurselen, Germany
[8] Ruhr Univ Bochum, St Anna Hosp Herne, Dept Gastroenterol, Acad Teaching Hosp, Bochum, Germany
[9] Heidelberg Univ, Acad Teaching Hosp, Klinikum Ludwigsburg, Dept Gastroenterol,Regionale Kliniken Holding & Se, Ludwigsburg, Germany
[10] Univ Berlin, Acad Teaching Hosp, Dept Gastroenterol, Sana Klinikum Lichtenberg, Berlin, Germany
[11] Univ Regensburg, Acad Teaching Hosp, Dept Gastroenterol & Endoscopy, Krankenhaus Barmherzige Bruder Regensburg, Regensburg, Germany
[12] Tech Univ Munich, Regensburg, Germany
[13] Univ Hannover, Acad Teaching Hosp, Dept Endoscopy & Ultrasound, Marienhosp Osnabruck, Osnabruck, Germany
[14] Univ Bonn, Acad Teaching Hosp, Dept Med & Gastroenterol, Gemeinschaftskrankenhaus Bonn, Bonn, Germany
[15] Univ Hosp Lubeck, Univ Hosp Schleswig Holstein, Dept Med 1, Lubeck, Germany
[16] Univ Hamburg, Acad Teaching Hosp, Dept Gastroenterol Hepatol & Endoscopy, Asklepios Klin Barmbek, Hamburg, Germany
[17] Univ Munich, Acad Teaching Hosp, Dept Gastroenterol, Klinikum Garmisch Patenkirchen, Garmisch Patenkirchen, Germany
[18] Univ Ulm, Acad Teaching Hosp, Dept Internal Med 1, Ostalb Klinikum Aalen, Aalen, Germany
[19] Univ Tubingen, Acad Teaching Hosp, Dept Internal Med, Klin Boblingen, Boblingen, Germany
[20] Univ Hannover, Acad Teaching Hosp, Allgemeines Krankenhaus Celle, Dept Gastroenterol, Celle, Germany
[21] Univ Munich, Acad Teaching Hosp, Dept Gastroenterol & Hepatol, Klinikum Traunstein, Traunstein, Germany
[22] Univ Hosp Eppendorf, Dept Interdisciplinary Endoscopy, Hamburg, Germany