[1] John Radcliffe Hosp, Oxford OX3 9DU, England
[2] Imelda Hosp, GI Clin Res Ctr, B-2820 Bonheiden, Belgium
[3] Hosp Univ Germans, Dept Gastroenterol & Hepatol, Barcelona 08916, Spain
[4] Univ London Imperial Coll Sci Technol & Med, Gastroenterol Sect, London W12 0NN, England
[5] Evangel Krankenhaus Kalk HGmbh, D-51103 Cologne, Germany
[6] Hop St Louis, Serv Gastroenterol, F-75010 Paris, France
[7] Hop Lariboisiere, AP HP, Medicosurg Dept Digest Dis, F-75010 Paris, France
[8] Univ Paris 07, Paris, France
[9] Univ Oxford, Oxford OX1 2JD, England
[10] Oxford Radcliffe Hosp NHS Trust, Oxford, England
[11] Akershus Univ Hosp, Dept Surg, N-1478 Lorenskog, Norway
[12] Catholic Univ Louvain, Univ Clin Gasthuisberg, Dept Abdominal Surg, B-3000 Louvain, Belgium
[13] Robert Bosch Krankenhaus, Innere Med Abt 1, Schwerpunkte Gastroenterol Hepatol & Endokrinol, D-70341 Stuttgart, Germany