This was the interesting conclusion last week from a comprehensive study in the Journal of the American Medical Association. Researchers compared emergency department use by Medicaid patients from 2001-2010 in eight states that impose copayments for nonurgent use of the emergency department with ten states having zero emergency department copayments. The study involved over 10,000 Medicaid patients and controlled for sex, age, race, marital status, income relative to the federal poverty level, educational level and self-reported health status.

The result? There was no more use of the emergency department by Medicaid patients over the ten years of the study in the eight states with ER copayments than in the ten states without any ER copayments. This is solid and interesting research looking at the effect of a specific change in the Medicaid program on thousands of patients over a decade. The study’s authors speculate that their finding may result from a variety of factors from the difficulty of hospitals determining what constitutes a “nonurgent” v. “urgent” visit to the growth in Medicaid enrollment during the study period.

For me, I can’t help think about the message sent to anyone who drives around a metropolitan area where various hospitals advertise ER waiting times with live minute counters displayed on major highway billboards. If the ER is only for emergencies, what is the point of these billboards? Or is it that hospitals are trying to bring non-urgent cases into their ERs as well?

The lesson from this study at least seems to be that whatever the reason, increasing ER copayments for Medicaid patients – as has been the case in multiple recent state waiver proposals enacting the Medicaid expansion under the Affordable Care Act – isn’t very effective at reducing non-emergency use of hospital emergency departments. For example, Indiana’s just-approved Medicaid waiver contains a graduated $25 copayment for “non-emergency use of the emergency department.” The authors of the study suggest that states look at other methods to promote the use of preventive care and encourage appropriate treatment settings since the ER “nonurgent” copay method does not appear to affect people’s use of hospital emergency departments.