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 two tables of edits. The Column One/Column Two Correct Coding Edits table and the Mutually Exclusive Edits table include code pairs that should not be reported together for a number of reasons explained in the Coding Policy Manual.