There are four Medicare modifiers that are commonly mistaken or used inappropriately. They have a lot in common, but misuse can cause an unnecessary denial.
Here are their official descriptions and an explanation of why the specific modifier should be used.
- (GA) Waiver of liability statement issued as required by payer policy, individual case: Use when a service might not be covered. The patient is notified and asked to sign an ABN. The GA modifier will indicate to the payer that the provider does have an ABN on file, if the service is not covered it will be denied as the patients’ responsibility.
- (GX) Notice of liability issued, voluntary under payer policy: When a service is never covered it is not necessary to obtain an ABN. If the GX modifier is appended, it indicates that although not required an ABN was obtained as a courtesy.
- (GY) Item or service statutorily excluded, does not meet the definition of any Medicare benefit, or, for non-Medicare insurers, is not a contract benefit. If a service is never covered and no notice of liability is required under the payers’ policy, denial automatically becomes the patients’ responsibility.
- (GZ) Item or service expected to be denied as not reasonable and necessary:Although an ABN was required at the time of service, one was not obtained. This denial would be the provider’s responsibility.
The proper use of modifiers can make the difference in payment or denial. More information about these modifiers can be found on the CMS website. There is also a Medicare Learning Network booklet (MLN006266) that discusses in depth the use of GA, GX, GY, and GZ.