The Center for Clinical Epidemiology and Population Health (CCEPH) is one of six research centers within the Marshfield Clinic Research Institute and consists of 30+ staff with 9 PhD/MD investigators, project managers, a research analytics team, and a research operations unit. Our research operations group includes research coordinators, telephone interviewers, and clerical support staff. Whether working with a single physician in rural Wisconsin or a large national research network, CCEPH has the research support services, experience, and expertise necessary to conduct consequential research on influenza, vaccines, chronic disease epidemiology, and health-care effectiveness.