[1] Univ Hosp Ghent, Dept Gastroenterol, De Pintelaan 185, B-9000 Ghent, Belgium
[2] Univ Hosp, Div Gastroenterol, Dept Med, 339 Windermere Rd, London, ON N6A 5A5, Canada
[3] Acad Med Ctr, Dept Gastroenterol, Meibergdreef 9, NL-1105 AZ Amsterdam, Netherlands
[4] Robarts Clin Trials, 100 Dundas St, London, ON N6A 5B6, Canada