1. Department of Epidemiology, Geisel School of Medicine at Dartmouth, Lebanon, New Hampshire
2. Division of Health and Social Care Research, King’s College London, London, England
3. Rollins School of Public Health, Winship Cancer Institute, Emory University, Atlanta, Georgia
4. VA Medical Center, White River Junction, Vermont
5. Department of Gastroenterology, The University of Texas MD Anderson Cancer Center, Houston
6. Department of Epidemiology, Geisel School of Medicine at Dartmouth, Lebanon, New Hampshire6Department of Medicine, University of North Carolina School of Medicine, Chapel Hill