[1] Western Univ, Dept Med, Div Gastroenterol, London, ON, Canada
[2] IRCCS Hosp San Raffaele, Gastroenterol & Endoscopy, Milan, Italy
[3] Univ Vita Salute San Raffaele, Milan, Italy
[4] London Hlth Sci Ctr, Lawson Hlth Res Inst, London, ON, Canada
[5] Dept Med, Div Gastroenterol, La Jolla, CA USA
[6] Univ Calgary, Div Gastroenterol & Hepatol, Calgary, AB, Canada
[7] Univ Calgary, Dept Community Hlth Sci, Calgary, AB, Canada
[8] Univ Federico II Naples, Dept Publ Hlth, Gastroenterol, Naples, Italy
[9] San Camillo Forlanini Hosp, Dept Gastroenterol & Digest Endoscopy, IBD Unit, I-00152 Rome, Italy
[10] Hosp Italiano Buenos Aires, Internal Med Serv, Rheumatol Unit, Peron 4190,C1199ABB, Buenos Aires, Argentina
[11] Inst Univ, Peron 4190,C1199ABB, Buenos Aires, Argentina
[12] Univ Western Ontario, Schulich Sch Med, London, ON, Canada
[13] Western Univ, Dept Med, Div Rheumatol, London, ON, Canada
[14] Univ Cattolica Sacro Cuore, IRCSS, Fdn Policlin Univ A Gemelli, Dept Rheumatol, Rome, Italy
[15] Univ Hosp Nancy, Dept Gastroenterol, F-54500 Vandoeuvre Les Nancy, France
[16] Nancy Univ Hosp, INFINY Inst, F-54500 Vandoeuvre Les Nancy, France
[17] Grp Hosp Prive Ambroise Pare Hartmann Paris IBD Ct, F-92200 Neuilly Sur Seine, France
[18] Western Univ, Dept Epidemiol & Biostat, London, ON, Canada