Emergency department (ED) spending has increased substantially over the past decade despite the number of visits per capita remaining relatively stable. 

The percentage of U.S. health spending attributable to the ED rose from 3.9% in 2006 to 5% in 2016, according to a study published in Health Affairs. Although this may be a small piece of total spending, policymakers have been particularly interested in this trend because of an increase in surprise billing in EDs. 

Researchers analyzed data from five states between 2012 and 2019 to determine the impact of price increases and upcoding on spending. Upcoding occurs when a provider submits codes for more severe and expensive diagnoses or procedures than those actually observed in or provided to the patient.