[1] University of California San Diego Health System,Division of Gastroenterology
[2] University of California San Diego Health System,Department of Radiology, Inflammatory Bowel Disease Center
[3] Western University,Robarts Clinical Trials. Inc
[4] Robarts Clinical Trials. Inc,Departments of Epidemiology and Biostatistics and Medicine
[5] Western University,Robarts Clinical Trials, Inc
[6] University of Western Ontario,undefined