Eighteen percent of adults under age 65 reported visiting a hospital emergency department at least once in 2014, about the same as in 2013, according to a report released today by the Centers for Disease Control and Prevention. About 35.2% of the ED visitors reported having Medicaid coverage, 16.6% were uninsured and 14.3% had private health insurance. The proportion of uninsured adults who reported using the ED at least twice in the past 12 months fell from 8% in 2013 to 5.9% in 2014. More than three-quarters of ED visitors attributed their most recent visit to a serious medical problem, while 11.8% said the doctor’s office or clinic was not open and 7% cited lack of access to other providers. After adjusting for demographic factors, Medicaid enrollees were more likely to attribute the visit to a serious problem than privately insured or uninsured adults, while uninsured adults were more likely to attribute it to lack of access to other providers. The findings are based on data from the CDC’s National Health Interview Survey in 2013 and 2014, immediately before and after implementation of the Affordable Care Act’s main health coverage provisions.