Variation in charges for emergency department visits across California

Previous studies have shown that charges for inpatient and clinic procedures vary substantially; however, there are scant data on variation in charges for emergency department (ED) visits. Outpatient ED visits are typically billed with current procedural terminology-coded levels to standardize the intensity of services received, providing an ideal element on which to evaluate charge variation. Thus, we seek to analyze the variation in charges for each level of ED visits and examine whether hospital- and market-level factors could help predict these charges.

Using 2011 charge data provided by every nonfederal California hospital to the Office of Statewide Health Planning and Development, we analyzed the variability in charges for each level of ED visits and used linear regression to assess whether hospital and market characteristics could explain the variation in charges.

Charges for each ED visit level varied widely; for example, charges for a level 4 visit ranged from $275 to $6,662. Government hospitals charged significantly less than nonprofit hospitals, whereas hospitals that paid higher wages, served higher proportions of Medicare and Medicaid patients, and were located in areas with high costs of living charged more. Overall, our models explained only 30% to 41% of the between-hospital variation in charges for each level of ED visits.

Our findings of extensive charge variation in ED visits add to the literature in demonstrating the lack of systematic charge setting in the US health care system. These widely varying charges affect the hospital bills of millions of uninsured patients and insured patients seeking care out of network and continue to play a role in many aspects of health care financing.