GAO says No Surprises Act is working, while radiologists, Congress push for reform
The No Surprises Act is working as it’s intended, pushing more healthcare services in-network, according to a new analysis from the Government Accountability Office. Meanwhile, radiologists and members of Congress continue to advocate for further changes to fix implementation of the landmark legislation.
On Feb. 19, the congressional watchdog agency released the results of its investigation of claims data from radiology and three other services often impacted by surprise billing. The GAO found that the percentage of in-network claims increased for 3 of the 4 services analyzed—emergency medicine, anesthesiology and air ambulances—between 2019 and 2023.
Radiology was the only exception, with the in-network rate remaining high and staying the same after implementation of the No Surprises Act in 2022. Members of Congress touted the findings on Feb. 23, contending that the NSA is helping protect patients, as it was intended. The report was mandated by Congress following passage of the legislation in 2020.
“This GAO report confirms what we hoped to see: the No Surprises Act is protecting patients and encouraging more care to be delivered in-network, which means fewer surprise bills and more certainty for families,” Rep. Jason Smith, R-Mo., chairman of the House Ways & Means Committee, said in a statement Monday.
However, Smith and colleagues believe the new GAO report underscores that further improvements must be made to ensure “the law is fully carried out as Congress wrote it.” They claim the Biden administration failed to properly implement the law, echoing W&M comments previously made in September.
House lawmakers are seeking changes to clarify and simplify criteria around whether claims are eligible for the law’s independent dispute resolution process. They also want greater transparency around how insurers calculate the “qualifying payment amount” used in arbitration.
“This will ensure Americans see the full affordability and transparency benefits the NSA promised” Smith said.
More on the report
The Government Accountability Office analyzed approximately 153 million radiology claims spanning a five-year period for its investigation. About 43% of these claims came from facilities while the other 57% were professional claims, typically billed by physicians or their practices.
Its investigation found that the percentage of in-network radiology claims remained high and largely unchanged between 2019 and 2023. For example, about 99% of facility claims, coming from hospitals, were in-network as of 2019. This stayed steady after NSA implementation at 98.9% in 2022 and 98.8% in 2023.
Same for professional claims submitted by radiologists, with 98.6% in-network as of 2019. This stayed flat following the law change, at 98.6% in 2022 and 98.8% in 2023. Air ambulances, meanwhile, saw a slight improvement, rising from about 89.3% of claims classified as in-network in 2019 to 96.2% in 2022, coinciding with the NSA’s implementation. Anesthesiology and emergency medicine also recorded small gains in their in-network percentages between 2021 and 2023, the GAO found, signifying the law is succeeding in pushing docs in-network and reducing surprise bills.
The watchdog group also analyzed how the No Surprises Act has impacted payments for radiology and other services since its implementation. Its investigation included $8 billion worth of in-network radiology expenditures billed by hospitals and another $958 in-network imaging expenses billed by physicians or their practices in outpatient hospitals.
They found that payments for in-network diagnostic radiology services—including both facility and professional claims—declined before implementation of the NSA and continued to dip in 2022 before increasing in 2023. However, these increases did not return radiology payments back to their 2019 levels.
Overall, during the five-year period, payments for in-network diagnostic radiology services billed by physicians dipped about 9.4% while facility claims fell about 2.2%. During that same time, payments for in-network emergency medicine services on the professional side fell 20.1% and decreased 12.2% on the facility side. In general, in-network anesthesiology claims also decreased, though payments for anesthesiology in ambulatory surgical centers were one exception, rising slightly in 2023.
“Payment changes for the selected services largely reflected continuations of trends prior to the No Surprises Act taking effect,” the Government Accountability Office noted in its summary of the report.
More NSA analyses
The GAO report is the latest in a long line of analyses related to the No Surprises Act. Last month, the Centers for Medicare & Medicaid Services released NSA data spanning the first half of 2025. It showed that providers are prevailing in about 88% of disagreements with insurers over out-of-network care.
Payer Perspectives released its own analysis of the January CMS data on Feb. 20. It noted that neurology and surgery providers using the independent dispute resolution system won at especially higher prevailing rates. In the first half of 2025, the median payment determination among disputes involving neurology and neuromuscular procedures was more than 23 times the "qualifying payment amount”—the median in-network rate calculated by payers.
For surgery, the median prevailing offer reached nearly 1,320% of the QPA. And for radiology, it was at about 486% of the QPA. A small number of providers and their representatives initiated most surprise billing disputes, the analysis added. These included multispecialty firms such as Team Health and SCP Health, alongside the fourth largest initiating party, Radiology Partners, “all backed by private equity firms.”
Insurers such as UnitedHealthcare and Aetna have taken Rad Partners to court over the past year, claiming the country’s largest radiology practice is improperly using the NSA’s arbitration process to increase profits.
“Fraud, abuse, and gaming in the federal IDR process are driving up costs for patients and employers,” AHIP, the largest insurer lobbying group in the U.S., told Radiology Business in response to the numbers shared by Payer Perspectives. “The latest CMS data shows extreme out‑of‑network charges and over $5 billion in waste tied to IDR misuse—ballooning costs to consumers. A small group of private‑equity‑backed providers and IDR middlemen are inflating systemwide costs, while health plans are working to keep costs down.”
In its own statement, Rad Partners said it “supports the core patient protections” of the NSA and believes the IDR process should be “efficient, predictable and fair for all stakeholders.” RP declined to comment on the UHC and Aetna lawsuits, only confirming they remain ongoing.
“Persistent high provider win rates in IDR are often a signal that payers’ QPAs (initial payments) are not aligned with the value and cost of delivering care,” Rad Partners said in a statement shared with Radiology Business. “We’re also awaiting the final IDR Operations Rule, which we expect will provide much-needed clarity on key operational aspects of the NSA and help strengthen the IDR process by reducing ineligible disputes and improving efficiency for all parties involved,” the RP representative added.
Last October, the American College of Radiology, alongside sister societies representing anesthesiologists and emergency physicians, also urged the administration to finalize the same IDR rule. First released in January 2024, the proposal would fix key parts of the NSA, improving efficiency while decreasing unnecessary utilization of the IDR process. However, two years later, the rule is yet to be finalized.
In other NSA-related news, Arizona lawmakers on Feb. 23 considered payer-friendly legislation that would impose caps on what physicians may offer in arbitration. However, amid strong opposition from the House of Medicine, the proposal has been tabled until the next legislative session.
Marty Stempniak has covered healthcare since 2012, with his byline appearing in the American Hospital Association's member magazine, Modern Healthcare and McKnight's. Prior to that, he wrote about village government and local business for his hometown newspaper in Oak Park, Illinois. He won a Peter Lisagor and Gold EXCEL awards in 2017 for his coverage of the opioid epidemic.