Washington is finally speeding up prior authorization. For laboratories, faster will not be enough. Federal rules that took effect in January require the major government-program payers to answer prior authorization requests within days rather than weeks. A proposed rule published in April would extend the same machinery to drugs while asking, for the first time, what to do about laboratory testing. But speed has never been the laboratory’s real problem. The evidence a payer wants before approving a test sits in clinical records the laboratory cannot see. Often the ordering physician cannot see all of them either. Until that evidence can be assembled before a request goes in, faster prior authorization will mostly mean faster denials.
The evidence a payer wants before approving a test sits in clinical records the laboratory cannot see. Often the ordering physician cannot see all of them either.
CMS itself has now described why laboratories sit at the bottom of this system. In the April proposal, the agency lays out the standard sequence with unusual candor. A physician writes the order. The patient walks down the hall to the draw station, and the specimen is collected the same day, before anyone involved has checked whether authorization was required. The laboratory learns the answer weeks later, when the claim is denied. A laboratory cannot pause this workflow to seek approval, because by the time the specimen arrives, the service has already happened. The agency’s request for information asks how often requests are denied for arriving after specimen collection and whether a test requisition form should count as valid medical documentation. Those are the right questions. They describe a process built on the assumption that evidence precedes service, applied to a field where reflex and confirmatory testing routinely generate their justification only after a first result exists.
The reforms deserve credit for what they do accomplish. Under the 2024 interoperability rule, Medicare Advantage, Medicaid, CHIP, and exchange plans began this January owing decisions within 72 hours for expedited requests and seven days for standard ones. Every denial now requires a specific reason, and approval and denial rates become public. By January 2027 those payers must operate electronic interfaces that let providers submit requests and receive decisions inside their own systems. A seven-day answer is materially better than a 45-day answer, and public denial rates give regulators leverage. None of that machinery, however, changes what a reviewer sees when the request opens.
What the reviewer wants is clinical justification. For a molecular test, that means how the diagnosis was established and which treatment decision depends on the result. That story is usually scattered between the ordering physician’s chart and institutions the ordering physician has never logged into. Assembling the story still means manual chart review and medical record abstraction across every institution involved. The laboratory, which absorbs the loss when the claim is denied, holds none of it, so documentation requests land on the party with the least access to the record. The appeals data shows where this ends. Medicare Advantage plans denied 4.1 million prior authorization requests in 2024. About one in nine of those denials was appealed, and 80.7% of the appeals succeeded. Appealed denials are a selected set, since providers contest the cases they expect to win. Even so, a denial that reverses at that rate reflects missing paperwork more than settled coverage policy. The paperwork was missing because nobody in the process could assemble evidence that existed all along.
Medicare Advantage plans denied 4.1 million prior authorization requests in 2024.
About one in nine of those denials was appealed, and 80.7% of the appeals succeeded.
The strongest counterargument is that automation will supply the evidence. The 2027 interfaces are designed to let a payer’s rules query the ordering clinician’s system and attach the required documentation without human effort. The industry pledge signed in June 2025 by insurers covering some 257 million Americans promises fewer prior authorization requirements to begin with. Where the ordering record is complete, automation will genuinely help. But an ordering physician’s system holds one institution’s slice of the patient, and automated extraction from an incomplete chart produces the same insufficient evidence at higher speed. The pledge has a similar limit. The medical necessity question does not disappear when the prior authorization requirement does. It moves to the claim, where the same missing records produce the same denial under a different name.
The deadlines were worth winning, and CMS deserves credit for asking laboratories the right questions in public. Comments on those questions closed in June, and the answer for laboratories will be written into the next rule. The remaining work is assembling the cross-institutional record before the request is submitted, so that when a reviewer opens the file, the justification is already in it. Until that happens, the reforms will deliver exactly what they were designed to deliver: a faster answer, and for laboratories the answer will too often still be “no.”
What did the 2024 CMS interoperability rule change about prior authorization?
Starting January 2026, Medicare Advantage, Medicaid, CHIP, and exchange plans must decide expedited requests within 72 hours and standard ones within 7 days, give a reason for every denial, and publicly report approval and denial rates.
Why do laboratories still face high denial rates despite faster decisions?
Speed does not fix the underlying problem: the clinical evidence a payer needs to approve a test usually sits in records outside the laboratory’s reach, so faster processing often just means faster denials.
What percentage of Medicare Advantage prior authorization denials get overturned on appeal?
About one in nine denials was appealed in 2024, and 80.7% of those appeals succeeded, a reversal rate that points to missing paperwork rather than a real coverage dispute.
Will the 2027 automated prior authorization interfaces solve the evidence gap for labs?
Only partially. Automation can speed up requests, but if the ordering system it queries only holds one institution’s slice of a patient’s record, it will surface the same incomplete evidence faster, not fix it.
What would actually close the evidence gap behind laboratory prior authorization denials?
Assembling the cross-institutional patient record before a request is submitted. xCures builds structured, source-linked patient histories across institutions to help close exactly this kind of gap.