Pathology/Lab Coding Alert

Question: Could you please explain the difference between Medically Unlikely Edits and Mutually Exclusive Edits under the National Correct Coding Initiative? They sound the same to me.

Tennessee Subscriber

Answer: Although the terms may sound alike, CMS has established Medically Unlikely Edits (MUEs) as a claims-editing parameter distinct from mutually-exclusive edits under the Correct Coding Initiative (CCI).

In fact, CMS has abandoned the distinction between mutually exclusive edits and comprehensive/component edits in favor of combining those edits under the umbrella of Procedure-to-Procedure (PTP) edits, also referred to as Column 1/Column 2 edits.

Purpose: The PTP edits identify different procedure codes that you should not bill together. CMS describes these as “automated prepayment edits that prevent improper payment when certain codes are submitted together.” On the other hand, the MUE edits define the maximum units of service that you can bill for a single CPT^® or HCPCS code for the same patient on the same date of service. For instance, 44970 (Laparoscopy, surgical, appendectomy) has an MUE of 1, because it would be impossible to remove more than one appendix from one specific patient.

For the PTP edits, CCI provides the following modifier indicators that tell you when or if you can override a given edit pair:

• 0 (Not allowed): You cannot use a modifier with this PTP code pair, because there are no circumstances in which both procedures of the PTP code pair should be paid for the same beneficiary on the same day by the same provider.
• 1 (Allowed): You may use an appropriate modifier such as 59 (Distinct procedural service) with this PTP code pair when conditions indicate that the procedures took place at a different anatomic site or during different operative sessions, for example.
• 9 (Not applicable): This indicator means that a CCI edit does not apply to this PTP code pair.

You can find more in-depth clarification on these indicators at www.cms.gov/Outreach-and-Education/Medicare-Learning-Network-MLN/MLNProducts/Downloads/How-To-Use-NCCI-Tools.pdf.