Part B Insider (Multispecialty) Coding Alert

Many MUEs make sense, but for those that don’t, you can fight back.

By now, most practices are familiar with Medicare’s medically unlikely edits (MUEs), which CMS instituted to prevent overpayments caused by gross billing errors. On April 1, CMS updated the MUE listing, and some of your favorite codes may now be limited by the bundles. When you scour your unpaid claims, make sure you are watching for MUE denials to ensure that you’re getting paid when appropriate but that you fight back when your claims are inappropriately denied.

Get to Know What MUE Edits Mean

While you shouldn’t stress too much, any practice filing a claim with Medicare should know what MUEs are and how they work. These edits limit the frequency a CPT® code can be used. Every practice should become aware of the denials, but should not always just accept all of them on the payer’s word.

The MUE list includes specific CPT® or HCPCS codes, followed by the number of units that CMS will pay. CMS developed the MUEs to reduce paid claims error rates in the Medicare Program. The first edits were implemented in January 2007, although the edits themselves became public in October 2008.

Some MUEs deal with anatomical impossibilities, while others edit automatically the number of units of service you can bill for a service in any 24-hour period. Still others limit codes according to CMS policy. For example, stereo frontal chest x-ray (71015) has an MUE value of "2," so you should not bill more than two units of this code on any particular day.

Anatomical example: The MUEs edit out and deny an erroneously coded claim for a hysterectomy (for example, 58150, Total abdominal hysterectomy [corpus and cervix], with or without removal of tube[s], with or without removal of ovary[s]) for a male patient.

Unit of service example: The edits also limit the claims for codes such as 99223 (Initial hospital care, per day, for evaluation and management of a patient…) to a single unit per calendar day. This makes sense because 99223 is a "per day" code.

Note: While CMS updates the MUE list every quarter, just like the Correct Coding Initiative (CCI) edits, it does not publish all MUEs. Remember that CCI doesn’t actually institute MUEs; CMS does. CCI edits relate to code pairings (whether two codes can be billed together). The published MUE list consists of most of the codes with MUE values of 1-3, but CMS does not publish all MUE values that are 4 or higher.

You can find the published edits on the CMS Web site. You can find a link to the MUEs and the MUE FAQs at www.cms.gov/Medicare/Coding/NationalCorrectCodInitEd/MUE.html.

Skip the ABN

Some practices believe that by having the patient sign an advance beneficiary notice (ABN) they can pass on the cost of procedures they know will be denied due to MUEs.

Reality: You cannot use ABNs to transfer responsibility for payment to the beneficiary. Even if you have the patient sign an ABN, you cannot pass on the cost of procedures you know will be denied due to MUEs.

CMS makes this rule very clear in its FAQs (http://questions.cms.hhs.gov), stating: "A provider/supplier may not issue an ABN for units of service in excess of an MUE. Furthermore, if services are denied based on an MUE, an ABN cannot be used to shift liability and bill the beneficiary for the denied services. It is a provider/supplier liability."

Override an MUE in Some Cases

Don’t think that even if your physician performs a legitimate, medically necessary procedure that violates MUE edits, you can’t override the edits.

Reality: CMS states that MUEs reflect the maximum number of units the vast majority of properly reported claims for a particular code would have, so you shouldn’t need to override them often. But you can override an MUE when your physician performs and documents a medically necessary number of services that exceed the limit. Check your payer’s reporting preference.

How it works: HCPCS offers modifier GD (Units of service exceeds medically unlikely edit value and represents reasonable and necessary services). But there is little information available on proper use of this modifier.

A CMS FAQ states that "since each line of a claim is adjudicated separately against the MUE value for the code on that line, the appropriate use of Current Procedural Terminology (CPT®) modifiers to report the same code on separate lines of a claim will enable a provider/supplier to report medically reasonable and necessary units of service in excess of an MUE value."

CMS notes that modifiers 76 (Repeat procedure or service by same physician or other qualified healthcare professiona) and 77 (Repeat procedure or service by another physician or other qualified healthcare professional) are among your options, as are the anatomical modifiers, such as RT (Right side) and LT (Left side). You may also use modifier 59 (Distinct procedural service), but only if no other modifier is appropriate.

You also may need to supply documentation showing medical necessity for the additional units.

Appeal, and Appeal Again

If you receive a claim denial due to MUEs, you can appeal the claim and you can address inquiries regarding the rationale for an MUE. The caveat: You may not receive the answer you want, and it will take a while to receive your response.

You should follow three steps during the appeals process:

Step 1: Determine the reason for the denial. First, figure out if you made a coding or billing error. If you find a coding error — such as the wrong number of units entered in the units box — submit a corrected claim. If you don’t find a coding or billing error, move on to the next step.

Step 2: Decide if you have a legitimate reason to appeal. If you believe there is medical necessity for the services over and above the allowable under the MUE, you should appeal to the contractor. If there is no medical necessity, take a look again at coding. Make sure the service is coded properly, and appropriate modifiers have been assigned.

Step 3: Appeal the claim. File an initial appeal with your carrier and follow the standard five-level Medicare appeals process. If appealing the claim due to a clinical reason, you may wish to employ clinical expertise when putting together your appeal letter.

Tip: Just because you win an appeal, you will not change the MUE edit. To get it changed, you need to go to your CAC (Carrier Advisory Committee) and your payer’s medical director and try to get the MUE edit changed. Winning some appeals with a terrific clinical case and documentation provides a good foundation to go to the CAC and the medical director to try to get the MUE edits changed.