Patients who have difficulty accessing their primary care provider after-hours are more likely to end up in the emergency department or go without care, according to a study published online today by Health Affairs. Based on a 2010 survey by the Center for Studying Health System Change, the study found that one in five people who attempt to contact their primary care provider after-hours find it very or somewhat difficult. The rate was higher among people who are uninsured (42%), covered by Medicaid or the Children's Health Insurance Program (31%), or report poor health (52%). About 38% of people who had difficulty contacting their primary care physician after hours reported visiting a hospital ED in the past 12 months, compared with 30% of those who had little or no difficulty. They also were more than twice as likely to report having an unmet medical need. About four in 10 people reported that their primary care practice offered extended hours, such as at night or on weekends.