• Faculty Members

Division of Gastroenterology

John Marshall

MD MSc FRCPC AGAF

Academic Interests

Dr. Marshall is an Associate Professor of Medicine at McMaster University and an active consultant gastroenterologist at Hamilton Health Sciences. He completed his B.A. and M.D. at Queen’s University, and then undertook his residency training and M.Sc. in Clinical Epidemiology & Biostatistics at McMaster University. There he is now a Full Member of the Farncombe Family Digestive Health Research Institute, Director of the Training Program in Adult Gastroenterology, and Head of Clinical Research for the Division of Gastroenterology.

His publications include over 90 academic papers and book chapters and 100 abstracts. He serves as an Associate Editor of the ACP Journal Club and Evidence-Based Medicine, Co-Editor of the Cochrane Collaboration IBD Review Group and a Member of Editorial Boards for the Canadian Journal of Gastroenterology and the World Journal of Gastroenterology.

Dr. Marshall has held a Clinician Scientist Award from the Canadian Institutes of Health Research (CIHR) and has received peer-reviewed research funding from several agencies including CIHR and the Crohn’s and Colitis Foundation of Canada. Recent honours include the Canadian Association of Gastroenterology (CAG) Young Investigator Award (2008), Fellowship in the American Gastroenterological Association (2007), the CAG Young Educator Award (2006) and the American College of Gastroenterology Governor’s Award for Excellence in Clinical Research (2003).

Dr. Marshall’s clinical and research interests include inflammatory bowel disease, post-infectious irritable bowel syndrome, gastrointestinal bleeding, clinical trials, clinical epidemiology, health outcomes and health economics.

Research Interests

Primary research interests relate to health technology assessment, economic analysis, endoscopy and clinical trials in the areas of inflammatory bowel disease, post-infectious irritable bowel syndrome and gastrointestinal bleeding. Some current and recent projects include:

• Meta-analyses of therapy for distal ulcerative colitis
• Conjoint analyses of preferences for colorectal cancer screening and ulcerative colitis therapy
• Prospective cohort studies of post-infectious IBS and inflammatory bowel disease in various cohorts including the Walkerton Health Study.
• Genetic analyses of predictors of post-infectious irritable bowel syndrome

Selected Publications

1. Barkun A, Bardou M, Marshall JK, for the Non-Variceal Upper GI Bleeding Consensus Group.  The Banff consensus conference on the management of patients with non-variceal upper gastrointestinal bleeding. Ann Intern Med 2003;139:843-857.
2. Marshall JK, Cawdron R, Zealley I, Riddell RH, Somers S, Irvine EJ.  Prospective comparison of small bowel meal with pneumocolon versus ileoscopy for diagnosis of ileal Crohn’s disease.  Am J Gastroenterol 2004;99:1321-9.
3. Marshall JK, Thabane M, Garg AX, Meddings J, Clark W, Collins SM, WEL Investigators. Intestinal permeability in patients with irritable bowel syndrome after a waterborne outbreak of acute gastroenteritis in Walkerton, Ontario. Aliment Pharmacol Ther 2004;20:1317-22.
4. Armstrong D, Marshall JK, Chiba N, Enns R, Fallone C, Fass R, Hollingworth R, Hunt R, Kahrilas P, Mayrand S, Moayyedi P, Paterson W, Sadowski D, van Zanten S. Canadian consensus conference on the management of gastroesophageal reflux in adults: update 2004. Can J Gastroenterol 2005:19:15-35.
5. Garg A, MacNab J, Haynes M, Clark W, Marshall JK, Devereaux PJ, Suri R, Ray J. Long-term health sequelae following water contaminated with Escherichia coli 0157:H7 and Campylobacter species: population sampling and assessing non-participation biases. Can J Public Health 2005;96:125-30.
6. Marshall JK, Gadowsky SL, Childs A, Armstrong D. Economic analysis of home versus hospital-based parenteral nutrition in Ontario, Canada. J Parent Enteral Nutr 2005;29:266-9.
7. Farrokhyar F, Marshall JK, Easterbrook B, Irvine EJ.  Functional gastrointestinal disorders and mood disorders in patients with inactive inflammatory bowel disease: prevalence and health impact.  Inflamm Bowel Dis 2006;12:38-46.
8. Garg AX, Marshall JK, Salvadori M, Thiessen HR, MacNab J, Suri RS, Haynes RB, Pope J, Clark W. A gradient of acute gastroenteritis to assess risk of long-term health sequelae after drinking bacteria contaminated water. J Clin Epidemiol 2006;59:421-8.
9. Borgaonkar MR, Ford D, Marshall JK, Churchill B, Collins SM. The incidence of irritable bowel syndrome among community subjects with previous acute enteric infection. Dig Dis Sci 2006;51:1026-32.
10. Marshall JK, Thabane M, James C. Randomized active and placebo-controlled endoscopy study of a novel protected formulation of oral alendronate. Dig Dis Sci 2006;51:864-8.
11. Marshall JK, Thabane M, Garg AX, Clark W, Salvadori M, Collins SM. Incidence and epidemiology of irritable bowel syndrome after a large waterborne outbreak of bacterial dysentery. Gastroenterology 2006;131:445-50.
12. Marshall JK.  Reporting ileocolonoscopy in inflammatory bowel disease.  Can J Gastroenterol 2006;20:399-400.
13. Marshall JK. Finding inflammatory bowel disease genes will not lead to a cure.  Can J Gastroenterol 2006;20:643-4. 
14. Anvari M, Allen CJ, Marshall J, Armstrong D, Goeree R, Ungar W, Goldsmith C.  A randomized controlled trial of laparoscopic Nissen fundoplication versus proton pump inhibitors for treatment of patients with chronic gastroesophageal reflux disease: one-year follow-up.  Surg Innov 2007;13:238-49 .
15. Comay D, Blackhouse G, Goeree R, Marshall JK. Photodynamic therapy for Barrett’s esophagus with high-grade dysplasia: a cost-effectiveness analysis. Can J Gastroenterol 2007;21:217-22.
16. Marshall JK, Thabane M, Borgaonkar M, James C. Post infectious irritable bowel syndrome following a foodborne outbreak of acute gastroenteritis attributed to a viral pathogen.  Clin Gastroenterol Hepatol 2007;5:457-60.
17. Thabane M, Kottachchi D, Marshall JK. Systematic review and meta-analysis to determine incidence and prognosis of post-infectious irritable bowel syndrome. Aliment Pharmacol Ther 2007;15:535-44.
18. Leonard J, Marshall JK, Moayyedi P.  Systematic review of the risk of enteric infection in patients taking acid suppression.  Am J Gastroenterol 2007;102:2047-56.
19. Marshall DA, Johnson FR, Phillips KA, Marshall JK, Thabane L, Ozdemir S, Kulin NA.  Measuring preferences for colorectal cancer screening using choice-format stated preferences.  Value Health 2007;10:415-30.
20. Panaccione R, Fedorak RN, Aumais G, Bernard EJ, Bernstein CN, Bitton A, Dieleman LA, Enns R, Franchimont D, Greenberg G, Griffiths AM, Marshall JK, Pare P, Patel S, Penner R, Render C, Ropeleski M, Seidman E, Steinhart AH. The use of infliximab in ulcerative colitis: systematic review and implications for clinical practice. Can J Gastroenterol 2008;22:261-72.
21. Marshall JK, Adams PA. The irritable infection. Can J Gastroenterol 2008;22:669-70.
22. Marshall JK. Post-infectious irritable bowel syndrome following water contamination. Kidney International 2008 [in press].
23. Marshall JK. Azathioprine, infliximab, certolizumab and adalimumab are effective for maintaining remission in Crohn’s disease. ACP J Club 2008 [in press].