As the nation’s health care system prepares for uninsured Americans to gain health insurance coverage under the Affordable Care Act, a question hangs over crowded hospital emergency departments: Will the newly insured make fewer ER visits than they do today?

According to the results of a new University of Michigan Medical School study in teens and young adults, the answer likely reflects a balance of ER care versus clinic visits. While the number of ER visits will likely stay about the same, clinic visits will likely go up.

The results, from the first national study of its kind, are published in Academic Emergency Medicine by a team led by U-M emergency physician Dr. Adrianne Haggins. The work was funded by the Robert Wood Johnson Foundation Clinical Scholars Program at U-M, and used data from the National Center for Health Statistics at the Centers for Disease Control and Prevention.

The researchers looked at patterns of emergency and non-emergency outpatient visits made by adolescents between the ages of 11 and 18 in the years before and after a major expansion of public health insurance coverage for this group. They were especially interested in ER care, given that it is unclear how the demand for both types of ambulatory care will change nationally when insurance is provided.