I am an Associate Professor of Clinical Medicine at the University of California San Diego and the San Diego Veterans Affairs Healthcare System, within the Division of Gastroenterology. My work focuses on the prevention and screening of colorectal cancer and polyps. I have been the leader of two large-scale comparative effectiveness randomized trials of strategies to boost colorectal cancer screening rates among the underserved, as well as numerous observational studies of the clinical and molecular epidemiology of digestive system cancers and neoplasia, including colorectal, hepatocellular, and pancreatic cancer. Currently funded research includes a Department of Veterans Affairs Merit Review to phenotype a cohort of over 2 million Veterans who have undergone colonoscopy 1999-2014, and use these data for epidemiologic research, as well as a National Cancer Institute-funded randomized trial of two strategies to increase screening rates among undesrerved populations. Additionally, I am San Diego local site PI for the Department of Veterans Affairs Cooperative Studies Program CONFIRM and Million Veteran Program initiatives. Further, I serve as vice-chair of the National Comprehensive Cancer Network guideline committees for genetic/high risk familial assessment and screening for colorectal cancer. Clinically, I practice general gastroenterology at VA San Diego and UC San Diego (including performance of gastrointestinal procedures), and specialize in the management of patients with hereditary colorectal cancer syndromes.