[1] Univ Calgary, Div Gastroenterol & Hepatol, Dept Med, Calgary, AB, Canada
[2] Univ Calgary, Dept Community Hlth Sci, Calgary, AB, Canada
[3] McMaster Univ, Div Gastroenterol, Dept Med, Hamilton, ON, Canada
[4] McMaster Univ, Farncombe Family Digest Hlth Res Inst, Hamilton, ON, Canada
[5] Alberta Hlth Serv, Knowledge Resource Serv, Calgary, AB, Canada
[6] Med Univ South Carolina, Div Gastroenterol & Hepatol, Charleston, SC USA
[7] Univ Calgary, Cumming Sch Med, Dept Oncol, Calgary, AB, Canada
[8] Northwestern Univ, Feinberg Sch Med, Div Gastroenterol, Chicago, IL USA
[9] Univ Colorado Anschutz Med Campus, Div Gastroenterol & Hepatol, Aurora, CO USA
[10] Alberta Hlth Serv, Canc Control Alberta, Dept Canc Epidemiol & Prevent Res, Calgary, AB, Canada