CMS Revises and Details Extrapolation Rules

Effective Jan. 2, 2019, the Centers for Medicare & Medicaid Services (CMS) radically changed its guidance on the use of extrapolation in audits by Recovery Audit Contractors (RACs), Medicare Administrative Contractors (MACs), Unified Program Integrity Contractors (UPICs), and the Supplemental Medical Review Contractor (SMRC).

Extrapolation is a veritable tsunami in Medicare/Medicaid audits. The auditor collects a small sample of claims to review for compliance, then determines the “error rate” of the sample. For example, if 500 claims are reviewed and one is found to be noncompliant for a total of $100, then the error rate is set at 20 percent. That error rate is applied to the universe, which is generally a three-year time period. It is assumed that the random sample is indicative of all your billings, regardless of whether you changed your billing system during that time period or maybe hired a different biller. In order to extrapolate an error rate, contractors must use a “statistically valid random sample” and then apply that error rate on a broader universe of claims, using “statistically valid methods.”

With extrapolated results, auditors allege millions of dollars of overpayments against healthcare providers – sometimes a sum of more than the provider even made during the relevant time period. It is an overwhelming impact that can put a provider and its company out of business.

Prior to this recent change to extrapolation procedure, the Program Integrity Manual (PIM) offered little guidance regarding the proper method for extrapolation.

Prior to 2019, CMS offered broad strokes with few details. Its guidance was limited to generally identifying the steps contractors should take: “a) selecting the provider or supplier; b) selecting the period to be reviewed; c) defining the universe, the sampling unit, and the sampling frame; d) designing the sampling plan and selecting the sample; e) reviewing each of the sampling units and determining if there was an overpayment or an underpayment; and, as applicable, f) estimating the overpayment.”

Well, Change Request 10067 overhauled extrapolation in a huge way.

The first modification to the extrapolation rules is that the PIM now dictates when extrapolation should be used.

Under the new guidance, a contractor “shall use statistical sampling when it has been determined that a sustained or high level of payment error exists. The use of statistical sampling may be used after a documented educational intervention has failed to correct the payment error.” This guidance now creates a three-tier structure:

  1. Extrapolation shall be used when a sustained or high level of payment error exists.
  2. Extrapolation may be used after documented educational intervention (such as in the Targeted Probe-and-Educate (TPE) program).
  3. It follows that extrapolation should not be used if there is not a sustained or high level of payment error or evidence that documented educational intervention has failed.

“High level of payment error” is defined as 50 percent or greater. The PIM also states that the contractor may review the provider’s past noncompliance for the same or similar billing issues or a historical pattern of noncompliant billing practice. This is critical because so many times providers simply pay the alleged overpayment amount if the amount is low or moderate in order to avoid costly litigation. Now, those past times that you simply paid the alleged amounts will be held against you.

Another monumental modification to RAC audits is that the RAC auditor now must receive authorization from CMS to go forward in recovering from the provider if the alleged overpayment exceeds $500,000 or is an amount that is greater than 25 percent of the provider’s Medicare revenue received within the previous 12 months.

The identification of the claims universe was also redefined. Even CMS admitted in the change request that, on occasion, “the universe may include items that are not utilized in the construction of the sample frame. This can happen for a number of reasons, including, but not limited to: a) some claims/claim lines are discovered to have been subject to a prior review; b) the definitions of the sample unit necessitate eliminating some claims/claim lines; or c) some claims/claim lines are attributed to sample units for which there was no payment.”

How many of you have been involved in an alleged overpayment in which the auditor misplaced or lost documents? I know I have. The new rule also states that the auditors must be able to recreate the sample and maintain all documentation pertinent to the calculation of an alleged overpayment.

High-volume providers should face a lower risk of extrapolation if their audited error rate is less than 50 percent and they do not have a history of noncompliance for the same or similar billing issues, or a historical pattern of noncompliant billing practice.

Facebook
Twitter
LinkedIn

Knicole C. Emanuel Esq.

For more than 20 years, Knicole has maintained a health care litigation practice, concentrating on Medicare and Medicaid litigation, health care regulatory compliance, administrative law and regulatory law. Knicole has tried over 2,000 administrative cases in over 30 states and has appeared before multiple states’ medical boards. She has successfully obtained federal injunctions in numerous states, which allowed health care providers to remain in business despite the state or federal laws allegations of health care fraud, abhorrent billings, and data mining. Across the country, Knicole frequently lectures on health care law, the impact of the Affordable Care Act and regulatory compliance for providers, including physicians, home health and hospice, dentists, chiropractors, hospitals and durable medical equipment providers. Knicole is partner at Nelson Mullins and a member of the RACmonitor editorial board and a popular panelist on Monitor Monday.

Related Stories

Leave a Reply

Please log in to your account to comment on this article.

Featured Webcasts

2026 ICD-10-CM/PCS Coding Clinic Update Webcast Series

Uncover essential coding insights with nationally recognized coding authority Kay Piper, RHIA, CDIP, CCS. Through ICD10monitor’s interactive, on‑demand webcast series, Kay walks you through the AHA’s 2026 ICD‑10‑CM/PCS Quarterly Coding Clinics, translating each update into practical, easy‑to‑apply guidance designed to sharpen precision, ensure compliance, and strengthen day‑to‑day decision‑making. Available shortly after each official release.

April 13, 2026

2026 ICD-10-CM/PCS Coding Clinic Update: Fourth Quarter

Uncover critical guidance on the ICD-10-CM/PCS code updates. Kay Piper reviews and explains ICD-10-CM/PCS coding guidelines in the AHA’s fourth quarter 2026 ICD-10-CM/PCS Coding Clinic in an easy to access on-demand webcast.

December 14, 2026

2026 ICD-10-CM/PCS Coding Clinic Update: Third Quarter

Uncover critical guidance on the ICD-10-CM/PCS code updates. Kay Piper reviews and explains ICD-10-CM/PCS coding guidelines in the AHA’s third quarter 2026 ICD-10-CM/PCS Coding Clinic in an easy to access on-demand webcast.

October 12, 2026

2026 ICD-10-CM/PCS Coding Clinic Update: Second Quarter

Uncover critical guidance on the ICD-10-CM/PCS code updates. Kay Piper reviews and explains ICD-10-CM/PCS coding guidelines in the AHA’s second quarter 2026 ICD-10-CM/PCS Coding Clinic in an easy to access on-demand webcast.

July 13, 2026

Trending News

Featured Webcasts

Compliance for the Inpatient Psychiatric Facility (IPF-PPS): Minimizing Federal Audit Findings by Strengthening Best Practices

Federal auditors are intensifying their focus on inpatient psychiatric facilities, using advanced data analytics to spotlight outliers and pursue high‑dollar repayments. In this high‑impact webcast, Michael Calahan, PA, MBA, Compliance Officer and V.P., Hospital & Physician Compliance, breaks down what regulators are really targeting in IPF-PPS admissions, documentation, treatment and discharge planning. Attendees will learn practical steps to tighten processes, avoid common audit triggers and protect reimbursement and reduce the risk of multimillion-dollar repayment demands.

April 9, 2026

Mastering MDM for Accurate Professional Fee Coding

In this timely session, Stacey Shillito, CDIP, CPMA, CCS, CCS-P, CPEDC, COPC, breaks down the complexities of Medical Decision Making (MDM) documentation so providers can confidently capture the true complexity of their care. Attendees will learn practical, efficient strategies to ensure documentation aligns with current E/M guidelines, supports accurate coding, and reduces audit risk, all without adding to charting time.

March 31, 2026

The PEPPER Returns – Risk and Opportunity at Your Fingertips

Join Ronald Hirsch, MD, FACP, CHCQM for The PEPPER Returns – Risk and Opportunity at Your Fingertips, a practical webcast that demystifies the PEPPER and shows you how to turn complex claims data into actionable insights. Dr. Hirsch will explain how to interpret key measures, identify compliance risks, uncover missed revenue opportunities, and understand new updates in the PEPPER, all to help your organization stay ahead of audits and use this powerful data proactively.

March 19, 2026

Top 10 Audit Targets for 2026-2027 for Hospitals & Physicians: Protect Your Revenue

Stay ahead of the 2026-2027 audit surge with “Top 10 Audit Targets for 2026-2027 for Hospitals & Physicians: Protect Your Revenue,” a high-impact webcast led by Michael Calahan, PA, MBA. This concise session gives hospitals and physicians clear insight into the most likely federal audit targets, such as E/M services, split/shared and critical care, observation and admissions, device credits, and Two-Midnight Rule changes, and shows how to tighten documentation, coding, and internal processes to reduce denials, recoupments, and penalties. Attendees walk away with practical best practices to protect revenue, strengthen compliance, and better prepare their teams for inevitable audits.

January 29, 2026

Trending News

Happy National Doctor’s Day! Learn how to get a complimentary webcast on ‘Decoding Social Admissions’ as a token of our heartfelt appreciation! Click here to learn more →

BLOOM INTO SAVINGS! Get 25% OFF during our spring sale through March 27. Use code SPRING26 at checkout to claim this offer.

CYBER WEEK IS HERE! Don’t miss your chance to get 20% off now until Dec. 1 with code CYBER25

CYBER WEEK IS HERE! Don’t miss your chance to get 20% off now until Dec. 2 with code CYBER24