The rule was written to empower patients. It has, instead, mostly empowered analysts.
The CMS Hospital Price Transparency Rule, which took full enforcement effect in 2022, requires hospitals to publish machine-readable files containing their negotiated rates with every commercial payer, their gross charges, and their cash prices. The architects of the rule imagined something like a Kayak for hospital services—consumers shopping across facilities before a colonoscopy or a hip replacement. What emerged is structurally incompatible with that vision but unexpectedly valuable for a different audience entirely.
Patients do not, in practice, shop for hospital services the way they shop for flights. Emergencies are not schedulable. Referral patterns are sticky. Network restrictions bind choices before a consumer encounters any price information. The information asymmetry the rule was designed to correct is downstream of a structural asymmetry—who you see when you’re sick is constrained long before you encounter a price list.
This is not a novel observation. Health economists have documented for years that price transparency alone, absent reference pricing or tiered benefit design, has minimal effect on consumer behavior. What the rule did produce—inadvertently, or perhaps deliberately—is a corpus of structured data about commercial healthcare pricing that had never before been publicly available.
The problem is that the corpus is barely legible. Hospitals file in dozens of formats, use different billing code schemas, bundle and unbundle service lines inconsistently, and occasionally publish files that satisfy the letter of the rule while obscuring the spirit of it. CMS has increased penalties for non-compliance, but the compliance it is measuring is procedural rather than substantive.
MedPricer.org has absorbed much of this structural disorder. By aggregating files across thousands of hospitals and attempting to standardize procedure codes, payer identifiers, and rate categories, the platform makes it possible to ask questions the raw data cannot answer: How much does Aetna pay for a knee replacement at hospitals in the same metropolitan statistical area? What is the ratio of commercial payer rates to Medicare rates at hospital systems that have recently undergone private equity acquisition? Are there systematic patterns in the hospitals that publish unusually low or incomplete rate data—and does that correlate with CMS compliance scores?
The regulatory gap this exposes is meaningful. CMS’s enforcement attention has focused on whether hospitals publish files, not whether those files accurately reflect actual contracted rates. Several academic analyses have found material discrepancies between published rates and rates documented in payer contracts obtained through litigation or state regulatory filings. MedPricer cannot validate rates against contracts it cannot access—but it can flag statistical outliers that warrant further scrutiny.
For policy analysts, this creates an interesting methodological opportunity. If a hospital system’s published rates for a high-volume procedure are systematically lower than those of regional competitors, the explanation might be genuine price leadership, or it might be selective reporting. A researcher who combines MedPricer’s rate data with Medicare cost report data and payer mix information from hospital financial filings can begin to distinguish between those hypotheses.
The second-order regulatory effect is subtler. Price transparency has created, for the first time, a basis for payer benchmarking in commercial markets. Employers who self-insure—and who bear the full cost of hospital price variation—can now use platforms like MedPricer to evaluate whether their third-party administrators are negotiating rates that reflect market conditions. This was nearly impossible before 2021. It remains difficult. But the data infrastructure now exists.
The Consolidated Appropriations Act of 2021 extended transparency requirements to health plans, requiring them to publish machine-readable files of their negotiated rates beginning in 2022. The plan transparency data is, if anything, messier than the hospital data. MedPricer’s architecture for handling hospital files may eventually extend to plan data—which would create a genuinely novel basis for comparative analysis across the entire commercial payment chain.
None of this is to argue that price transparency was well-designed policy. The rule has produced data of uncertain accuracy, formatted inconsistently, used almost entirely by analysts rather than the consumers it nominally targeted. That gap between stated rationale and actual effect is itself a subject worth more rigorous scrutiny than it has received.
