Department SummaryThe California Health Interview Survey (CHIS) is the largest population-based state health survey in the nation and the premier source of credible and comprehensive data on the health and health care needs of Californias large and diverse population. A model for health surveys for other states, CHIS is committed to ensuring everyone has access to data policymakers, advocates, health care providers, community organizations, researchers, journalists, and the public to fight for policies that will improve the lives of Californians through better health and health care. We make sure that data didnt just sit on a shelf but was accessible and widely disseminated through our public use files and AskCHIS free web query tool.