​Asthma is one of the most common chronic diseases among children in the U.S. and a leading cause of hospitalizations and absences from school. Asthma rates vary by region, demographics, environment, physician diagnostic practices, and access to care. Although identifying the impact of independent risk factors for asthma is difficult, low-income and minority children are at disproportionately high risk for severe symptoms, missed school days, and emergency room visits due to asthma. The prevalence of asthma for all California kids was 15.2%, according to 2015-2016 California Health Interview Survey (CHIS) data on this dashboard. But individual county rates varied widely, from 3.2% in San Luis Obispo County to 34.6% in Kings County.