[1] Robarts Clin Trials Inc, Robarts Res Inst, London, ON, Canada
[2] Univ Western Ontario, Dept Med, London, ON N6A 5K8, Canada
[3] Univ Western Ontario, Dept Epidemiol & Biostat, London, ON N6A 5K8, Canada
[4] St Pauls Hosp, Dept Gastroenterol, Vancouver, BC V6Z 1Y6, Canada
[5] Univ Calif San Diego, Div Gastroenterol, La Jolla, CA 92093 USA
[6] Mt Sinai Hosp, Div Gastroenterol, Toronto, ON M5G 1X5, Canada
[7] Univ Calgary, Dept Med, Div Gastroenterol & Hepatol, Calgary, AB, Canada
[8] McGill Univ, Ctr Hlth, Div Gastroenterol, Montreal, PQ, Canada
[9] Univ Laval, Hop St Sacrement, CHAUQ, Quebec City, PQ, Canada
[10] Translat Res Ctr Gastrointestinal Disorders, Dept Clin & Expt Med, Leuven, Belgium
[11] Univ Amsterdam, Acad Med Ctr, Dept Gastroenterol, NL-1105 AZ Amsterdam, Netherlands
[12] Dalhousie Univ, Div Gastroenterol, Halifax, NS, Canada