Optometry Coding & Billing Alert

Question: I'm about to send a bill to Medicare for a service I'm pretty sure will be denied. Should I use modifier -GA or -GY?


Pennsylvania Subscriber

Answer: It depends on why you think the service will be denied, and whether you have an advance beneficiary notice (ABN) on file. Many services - such as refraction (92015, Determination of refractive state) - are statutorily excluded from Medicare payment, and you don't need an ABN to bill the patient directly for these "non-covered services." Since Medicare won't pay for such services, you don't have to submit a bill to Medicare for the patient.

Modifier -GY: If the patient insists that you submit a bill to Medicare for a non-covered service like refraction, use modifier -GY (Item or service statutorily excluded or does not meet the definition of any Medicare benefit), which notifies Medicare that you're aware that the service isn't covered, but you're billing simply to obtain a denial. Medicare will automatically deny the claim, and the EOB will state that the patient is liable for the charge. For more information on -GY, go to www.cms.hhs.gov/medlearn/modchtgy.pdf.

Modifier -GA: Append modifier -GA (Waiver of liability statement on file) when a service is sometimes payable, but you're not sure if CMS will pay for it in this particular case (for example, a glaucoma screening that may be denied for frequency reasons). The patient must sign an ABN. If the claim is denied, the EOB will state that the patient is liable for the charge. For more information on -GA, go to www.cms.hhs.gov/medlearn/modchtga.pdf.

Modifier -GZ: Append modifier -GZ (Item or service expected to be denied as not reasonable and necessary) when you expect the service to be rejected as not medically necessary and you do not have an ABN on file.

Hidden trap: If Medicare rejects the claim, you may not be able to collect from the patient. However, modifier -GZ protects you from fraud charges by indicating that you're not expecting payment for services you know are not medically necessary. For more information on -GZ, go to www.cms.hhs.gov/medlearn/modchtgz.pdf.

Advice for Reader Questions and You Be the Expert contributed by David Gibson, OD, FAAO, practicing optometrist in Lubbock, Texas; and Charles Wimbish, OD, president of Wimbish Consulting Group in Martinsville, Va.