Association of Surprise-Billing Legislation with Prices Paid to In-Network and Out-of-Network Anesthesiologists in California, Florida, and New York: An Economic Analysis.

Importance: Several states have passed surprise-billing legislation to protect patients from unanticipated out-of-network medical bills, yet little is known about how state laws influence out-of-network prices and whether spillovers exist to in-network prices. Objective: To identify any changes in prices paid to out-of-network anesthesiologists at in-network facilities and to in-network anesthesiologists before and after states passed surprise-billing legislation. Design, Setting, and Participants: This retrospective economic analysis used difference-in-differences methods to compare price changes before and after the passage of legislation in California, Florida, and New York, which passed comprehensive surprise-billing legislation between January 1, 2014, and December 31, 2017, to 45 states that did not. Commercial claims data from the Health Care Cost Institute were used to identify prices paid to anesthesiologists in hospital outpatient departments and ambulatory surgery centers. The final analytic sample comprised 2 713 913 anesthesia claims across the 3 treated states and the 45 control states. Exposures: Temporal and state-level variation in exposure to surprise-billing legislation. Main Outcomes and Measures: The unit price (allowed amounts standardized per unit of service) paid to out-of-network anesthesiologists at in-network facilities and to in-network anesthesiologists. Results: This retrospective economic analysis of 2 713 913 anesthesia claims found that after surprise-billing laws were passed in 3 states, the unit price paid to out-of-network anesthesiologists at in-network facilities decreased significantly in 2 of them: California, -$12.71 (95% CI, -$25.70 to -$0.27; P = .05) and Florida, -$35.67 (95% CI, -$46.27 to -$25.07; P < .001). In New York, a decline in the overall out-of-network price was not statistically significant (-$7.91; 95% CI, -$17.48 to -$1.68; P = .10); however, by the fourth quarter of 2017, the decline was -$41.28 (95% CI, -$70.24 to -$12.33; P = .01). In-network prices decreased in California by -$10.68 (95% CI, -$12.70 to -$8.66; P < .001); in Florida, -$3.18 (95% CI, -$5.17 to -$1.19; P = .002); and in New York, -$8.05 (95% CI, -$11.46 to -$4.64; P < .001). Conclusions and Relevance: This retrospective study found that prices paid to in-network and out-of-network anesthesiologists in hospital outpatient departments and ambulatory surgery centers decreased after the introduction of surprise-billing legislation, providing early insights into how prices may change under the federal No Surprises Act and in states that have recently passed their own legislation.