The OIG Is Back — And Their Math Doesn’t Add Up

By Elizaveta Bannova, Billing Department, WCH

If you were hoping the OIG’s audit activity would stay quiet through the summer, that hope just expired. After a prolonged pause, the HHS Office of Inspector General has returned to auditing hospital inpatient admissions with what appears to be full momentum — and their recent work raises questions that go in two directions at once: about hospital documentation practices, and about the quality of the auditors doing the reviewing.

The latest example is a published audit of Jefferson Regional Medical Center in Arkansas, where the OIG identified what it characterized as at least $4.7 million in Medicare overpayments. The audit covers inpatient admissions, and as with most OIG hospital audits, the findings invite scrutiny on both sides of the table.

A Case Study in Contested Clinical Judgment

The OIG’s case description goes like this: a patient with a history of hypertension presented with acute high blood pressure. Blood pressure responded to oral medications. Cardiac enzymes were negative, the EKG was unremarkable. The patient was admitted for medication adjustment, with the admitting physician expecting discharge within 24 to 48 hours. The OIG’s conclusion: this should not have been billed as an inpatient admission.

But here is what the OIG’s version leaves out, which the hospital provided in its response. The patient presented not just with elevated blood pressure but with a headache and congested cough. The admission diagnosis was acute exacerbation of heart failure in addition to elevated blood pressure. The patient was treated in the intensive care unit, where the clinical goal was to lower blood pressure in a carefully controlled fashion — specifically to avoid compromising cerebral, coronary, or renal perfusion. That is a materially different clinical picture than “admitted for medication adjustment.”

The distinction matters enormously for anyone who has ever managed a hypertensive emergency versus urgency, or who understands why a patient with decompensated heart failure and elevated blood pressure lands in the ICU rather than an observation bay. An auditor who reads “blood pressure responded to oral medications” and concludes the admission was unnecessary is missing the clinical reasoning that drove the admission in the first place: the concern was not just the number on the blood pressure cuff, it was what that number was doing to a heart that was already failing.

The Two-Midnight Rule Is Not the 48-Hour Rule

There is a second problem with the OIG’s analysis that should concern any compliance professional reading this audit: the OIG’s own framing suggests their auditor may not understand the governing standard.

The Two-Midnight Rule — which has been the benchmark for Medicare inpatient admission appropriateness since 2013 — states that an inpatient admission is generally appropriate when a physician expects the patient to require care spanning at least two midnights. The OIG’s write-up references the admitting physician’s expectation of a 24 to 48-hour stay as though it undermines the inpatient status. It does not. A patient admitted in the afternoon who is expected to stay 48 hours will, by definition, cross two midnights. The Two-Midnight Rule is satisfied. The OIG auditor appears to have confused “less than 48 hours” with “doesn’t meet inpatient criteria,” which is not the standard and has not been since the rule was implemented.

This is not a minor technical quibble. If OIG auditors are applying the wrong standard to clinical cases, the resulting overpayment determinations — and the extrapolated figures built on top of them — are methodologically compromised.

The $78 Problem

Speaking of extrapolation: the OIG also flagged three cases in which the hospital used incorrect discharge status codes, noting that Medicare paid more than it should have as a result. The total overpayment attributed to those three cases? $78. That is $26 per admission.

This number does not make sense. Discharge status code errors typically affect payment when a patient is transferred to another facility or discharged to a skilled nursing facility, triggering a per-diem adjustment to the DRG payment. Those adjustments operate on a per-diem rate tied to the DRG value. There is no DRG in the Medicare payment system where a per-diem adjustment calculates to $26 per case. The math simply does not work.

Yet that $78 figure was included in the audit findings, added to the total overpayment pool, and used as part of the basis for the extrapolated overpayment estimate. Extrapolation multiplies errors — which means that if the underlying $78 is wrong, its amplified version in the final overpayment figure is also wrong.

PEPPER Updates You Should Not Ignore

On a more operational note, two PEPPER updates are now live that require attention from anyone involved in utilization review.

Critical access hospitals and hospices now have access to their fiscal year 2025 PEPPER data. Because these provider types receive their data only once per year, the release is significant — it represents a full-year view of billing patterns relative to national and jurisdictional comparators, covering the metrics most likely to draw OIG scrutiny.

For acute care hospitals, PEPPER data for the first quarter of 2026 — covering claims from October through December 2025 — has been released. If you had a Q4 utilization review presentation already staged and ready, it needs to be updated with this new data before it goes in front of your committee.

PEPPER exists precisely for moments like this one: when OIG audits are ramping up, knowing where your patterns diverge from benchmarks is not optional intelligence — it is your first line of defense.

What This Means for Providers

The OIG’s return to active hospital auditing is not a signal to panic, but it is a signal to prepare. The Jefferson Regional audit illustrates two risks that are entirely manageable with the right processes in place.

First, documentation needs to capture clinical reasoning, not just clinical findings. A chart that says “blood pressure responded to oral medications” and stops there is technically accurate but clinically incomplete. The documentation should explain why the patient required inpatient-level monitoring, what the physician was watching for, and what would have happened if the patient had been sent home. The Two-Midnight Rule is fundamentally about physician judgment — and that judgment needs to be legible in the record.

Second, discharge status coding deserves the same rigor as DRG assignment. The $78 finding in this audit sounds trivial, but incorrect status codes that get swept into an extrapolation calculation are not trivial. They become part of a number that can reach into the millions. Routine coding audits that catch status code errors before a claim is submitted are far cheaper than correcting them after an OIG review.

The OIG is back. The question is whether your documentation and coding practices are ready for the scrutiny.

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