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National Correct Coding Initiative Edits

Notice:  The MUE file for the third quarter of 2014 has been updated to contain two additional fields of information.  One field indicates whether each MUE is a claim line or date of service edit.  (See MLN SE1422.)  The second field provides the rationale for each MUE.  Information about MUE rationales is available in the National Correct Coding Initiative Policy Manual for Medicare Services, Chapter 1, Section V (Medically Unlikely Edits).  Although the usual formatted version of the MUE file published July 1, 2014 and the updated version published July 3, 2014 are available on the CMS website in the third quarter of 2014, only the updated MUE file format will be available in future calendar quarters.

Important notice to all NCCI Users concerning the National Correct Coding Initiative Policy Manual for Medicare Services:

The annual updated version of the National Correct Coding Initiative Policy Manual for Medicare Services will be effective January 1, 2015.  Additions/revisions to the manual have been italicized in red font.

National Correct Coding Initiative

The CMS developed the National Correct Coding Initiative (NCCI) to promote national correct coding methodologies and to control improper coding leading to inappropriate payment in Part B claims. The CMS developed its coding policies based on coding conventions defined in the American Medical Association's CPT Manual, national and local policies and edits, coding guidelines developed by national societies, analysis of standard medical and surgical practices, and a review of current coding practices. The CMS annually updates the National Correct Coding Initiative Coding Policy Manual for Medicare Services (Coding Policy Manual).  The Coding Policy Manual should be utilized by carriers and FIs as a general reference tool that explains the rationale for NCCI edits.

Carriers implemented NCCI edits within their claim processing systems for dates of service on or after January 1, 1996.

A subset of NCCI edits is incorporated into the outpatient code editor (OCE) for OPPS and therapy providers (Skilled nursing facilities (SNFs), comprehensive outpatient rehabilitation facilities (CORFs), outpatient physical therapy and speech-language pathology providers (OPTs), and home health agencies (HHAs) billing under TOBs 22X, 23X, 75X, 74X, 34X).

The purpose of the NCCI edits is to prevent improper payment when incorrect code combinations are reported. The NCCI contains one table of edits for physicians/practitioners and one table of edits for outpatient hospital services. The Column One/Column Two Correct Coding Edits table and the Mutually Exclusive Edits table have been combined into one table and include code pairs that should not be reported together for a number of reasons explained in the Coding Policy Manual. 

The Correspondence Language Manual available below has been written and maintained for utilization by the Medicare Contractors to answer routine correspondence inquiries about the NCCI procedure to procedure and MUE edits.  The general correspondence language paragraphs explain the rationale for the edits.  The section-specific examples add further explanation to the NCCI or MUE edits and are sorted by edit rationale and CPT code section (00000, 10000, 20000, etc.).  Please refer to the Introduction of this Manual for additional guidance about its use.  

Inquiries about the NCCI program, other than those related to NCCI edits, should be sent to the following email address:

This web page provides information to providers on Medicare's NCCI edits but does not address specific NCCI edits. If the viewer has concerns about specific NCCI edits, he/she may submit comments in writing to:

National Correct Coding Initiative
Correct Coding Solutions LLC
P.O. Box 907
Carmel, IN 46082-0907

Attention:  Niles R. Rosen, M.D., Medical Director and Linda S. Dietz, RHIA, CCS, CCS-P, Coding Specialist

Fax #:  317-571-1745