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MLN Educational Tool

MLN901346 — March 2022

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How to Use the Medicare National Correct Coding Initiative (NCCI) Tools

What is the Medicare NCCI?

The Medicare NCCI promotes correct coding methodologies and controls improper coding leading to improper payment. Coding policies are based on coding conventions defined in the American Medical Association’s (AMA’s) Current Procedural Terminology (CPT) Manual, national and local Medicare policies and edits, coding guidelines developed by national societies, standard medical and surgical practice, and/or current coding practice.

Before implementing NCCI edits, CMS shares all NCCI proposed edits for review and comment with the AMA, national medical and surgical societies, and other national health care organizations, including non-physician professional societies, hospital organizations, laboratory organizations, and durable medical equipment (DME) organizations.

Background: NCCI Edits

NCCI has 2 provider-type choices of Procedure to Procedure (PTP) code pair edits and 3 provider-type choices of Medically Unlikely Edits (MUEs).

PTP Code Pair Edits

PTP code pair edits are automated prepayment edits that prevent improper payment when you report certain codes together for Part B-covered services.

  1. Hospital PTP Edits
    PTP edits apply to Types of Bills (TOBs) subject to the Outpatient Code Editor (OCE) for the Outpatient Prospective Payment System (OPPS). These edits apply to outpatient hospital services and other facility services including, therapy providers in Part B Skilled Nursing Facilities (SNFs), comprehensive outpatient rehabilitation facilities (CORFs), outpatient physical therapy and speech language pathology providers (OPTs), and certain claims for home health agencies (HHAs) billing under TOBs 22X, 23X, 75X, 74X, 34X.
  2. Practitioner PTP Edits
    PTP code pair edits apply to physicians and Ambulatory Surgery Center (ASCs) claims.

MUEs

Medicare Administrative Contractors (MACs) and DME MACs use MUEs, to reduce the improper payment rate for Part B claims. An MUE for a HCPCS/CPT code is the maximum units of service (UOS) that you would report under most circumstances for a single patient on a single date of service. Not all HCPCS/CPT codes have an MUE.

  1. Practitioner MUEs
    These edits apply to all claims you submit for physician.
  2. Durable Medical Equipment (DME) Supplier MUEs
    These edits apply to claims you submit to DME MACs. (This file includes HCPCS A-B and E-V codes and HCPCS codes under the DME MAC jurisdiction.)
  3. Facility Outpatient MUEs
    These edits apply to all claims for TOBs 13X, 14X, 85X Critical Access Hospitals (CAHs), and 087x Opioid Treatment Programs (OTPs).

MUE values aren’t usage guidelines. You should only report units of service (UOS) that are medically reasonable and necessary. MACs may select your claims for medical review even if you report UOS less than or equal to the MUE value for a code.

Modifiers

Modifiers consist of 2 alphanumeric characters. You should only apply modifiers to HCPCS/CPT codes if the clinical circumstances justify using them. You shouldn’t apply a modifier to a HCPCS/CPT code just to bypass an MUE or PTP code pair edit if the clinical circumstances don’t justify using it.

If the Medicare Program imposes restrictions on applying a modifier, you should only use the modifier to bypass a PTP code pair or MUE edit if the Medicare restrictions are fulfilled. You’ll learn more about modifiers on pages 10 and 11 of this booklet.

Add-On Codes

An Add-on Code (AOC) is a HCPCS/CPT code that describes a service that, with rare exception, a practitioner does in conjunction with another primary service. An AOC is rarely eligible for payment if it’s the only procedure you report.

For information about AOC edits, refer to Add-on Code Edits.

Why Would You Use the NCCI Webpage, Tables, and Manual?

Accurate coding and reporting of services are critical aspects of proper billing. A denial of services due to an MUE is a coding denial, not a medical necessity denial. You can’t bill a Medicare patient for a service denied based on PTP code pair edits or MUEs. It’s not appropriate to use an Advance Beneficiary Notice of Noncoverage (ABN) to shift liability to the Medicare patient for UOS denied based on an MUE or coding denial. The tools on the NCCI webpage, including the NCCI Policy Manual for Medicare, will help you avoid coding and billing errors and resulting payment denials.

Note: It’s important to understand, that the NCCI doesn’t include all possible combinations of correct coding edits or kinds of unbundling. You’re required to code correctly even if edits don’t exist to prevent improper coding. If you decide claims have been coded incorrectly, contact your MAC about potential payment adjustments. Find your MAC’s website.

You’re subject to the statutory requirements found in section 1128J(d) of the Social Security Act and could face potential False Claims Act (FCA) liability, Civil Monetary Penalties Law (CMPL) liability, and exclusion from federal health care programs if you don’t report and return an overpayment.

For more information on overpayments, refer to the Medicare Overpayments Fact Sheet.

How Up to Date are the NCCI Tables?

CMS updates the NCCI Edits webpage with the most recent NCCI tables on a quarterly basis.

Select the Quarterly PTP and MUE Version Update Changes link in the left navigation menu of the NCCI Edits webpage to find quarterly changes to the PTP and MUE tables.

How to Find the NCCI Tables and Manual

You can access the NCCI Policy Manual, MUEs, and PTP edits through NCCI Edits webpage.

Links to the PTP Coding Edits, MUEs, and NCCI policy manual webpages are in the menu on the left side of the NCCI Edits webpage.