[1] McGill Univ, Jewish Gen Hosp, Lady Davis Inst Med Res, Ctr Clin Epidemiol & Community Studies, Montreal, PQ H3T 1E2, Canada
[2] McGill Univ, Dept Med, Ctr Hlth, Div Gastroenterol, Montreal, PQ, Canada
[3] Technion Israel Inst Technol, Rambam Hlth Care Campus, Dept Gastroenterol, Haifa, Israel