No Physician or Other Licensed Health Care Provider Order for this Item or Service
None, cannot be used when HHABN or ABN is required, recommend documenting records; liability is provider unless other modifiers are used (-GL, -GY, or –TS)
To signify a line-item should not receive payment when Medicare requires orders to support delivery of a item or service (i.e., TOBs 21x, 22x, 32x, 33x, 34x, 74x, 75x, 76x, 81x, 82x, 85x)
When orders required, line item is submitted as non-covered and services
Waiver of Liability Statement Issued, as Required by Payer Policy
ABN required; beneficiary liable
To signify a line item is linked to the mandatory use of an ABN when charges both related to and not related to an ABN must be submitted on the same claim
Line item must be submitted as covered; Medicare makes a determination for payment
Specifically, effective April 1, 2010, two HCPCS level 2 modifiers have been updated to distinguish between voluntary, and required, uses of liability notices.
Those modifiers are:
• Modifier – GA has been redefined to mean “Waiver of Liability Statement Issued as Required by Payer Policy,” and should be used to report when a required
• A new modifier (-GX) has been created with the definition “Notice of Liability Issued, Voluntary Under Payer Policy” and is to be used to report when a ABN was issued for a service.
Reasonable and Necessary Item/Service Associated with a –GA or –GZ modifier
ABN required if –GA is used; no liability assumption since this modifier should not be used on institutional claims
Not used on institutional claims. Use –GA or –GZ modifier as appropriate instead
Institutional claims submitted using this modifier are returned to the provider
Medicare Part B covers a variety of services and items, including physician office visits, outpatient procedures, laboratory tests, and durable medical equipment, prosthetics, orthotics, and supplies (DMEPOS). Covered services and items must be reasonable and necessary for the diagnosis or treatment of illness or injury, or to improve the functioning of a malformed body part.1
As discussed in more detail below, providers and suppliers use G modifiers to alert Medicare when they bill for services or items that they expect to be denied as either not reasonable and necessary (GA and GZ modifiers) or because they are not covered by Medicare (GY and GX modifiers).
In a 2009 report, the Office of Inspector General (OIG) raised concerns about the use of GA and GZ modifiers and about Medicare inappropriately paying for some claims with these modifiers. The report looked at claims for pressure-reducing support surfaces and found that Medicare paid for 72 percent of all pressure-reducing support surface claims with GA or GZ modifiers.2
This amounted to over $4 million in potentially inappropriate payments.
GA and GZ Modifiers
Providers and suppliers use GA and GZ modifiers to bill for certain services or items that they expect to be denied as not reasonable and necessary.3 They may use these modifiers when they are uncertain about whether a claim should be paid. For example, a provider may not know whether a beneficiary already had a particular laboratory test that Medicare covers only once a year 4 or a supplier may suspect that the beneficiary already has the item it is providing.5 GA Modifiers: Beginning in January 2002, Medicare required providers and suppliers to use the GA modifier for claims they expect to be denied as not reasonable and necessary for which they have on file an Advance Beneficiary Notice (ABN) signed by the beneficiary. One of the purposes of the ABN is to inform the beneficiary that Medicare certainly or probably will not pay for the service or item on that occasion. The GA modifier may be used only if a beneficiary signed an ABN indicating that he or she accepts liability for the cost of the service or item if Medicare does not pay for it.
Medicare prohibits the routine use of ABNs. However, it does allow for certain exceptions, such as when a service or item has a frequency limit on coverage.7
For example, laboratories may routinely use ABNs because Medicare places frequency limitations on many laboratory services and laboratories may not be able to determine whether a beneficiary has already exceeded the limit for a test. Providers and suppliers may also use these modifiers when they are certain that the claim should not be paid. For example, a provider may know that Medicare does not pay for a particular test for a beneficiary with a given condition, but because the beneficiary requests it, the provider submits the claim to Medicare for a decision.6
The beneficiary may need Medicare to deny the claim so that it can be submitted to the beneficiary’s secondary insurance.
Medicare Part B Claims Processing
CMS contracts with Medicare Administrative Contractors (MAC) to process and pay Part B claims.12 These contractors also apply claims processing “edits”—i.e., system checks—to prevent improper payments; conduct medical reviews and data analyses of claims; and conduct outreach and education to providers. Edits flag a claim for automatic denial or for contractor review to ensure that the claim is appropriate. CMS provides contractors with various instructions about how to process claims with G modifiers. CMS required contractors o automatically deny claims with GZ modifiers for services or items that were provided on or after July 1, 2011.
13 Currently, CMS does not have any specific instructions for claims with GA modifiers, except for those submitted with both a GA and GZ modifier; CMS instructs contractors to treat such claims as unprocessable.14 For claims with GY modifiers, CMS allows contractors to deny these claims at their discretion. Finally, CMS has not issued instructions for processing Part B claims with GX modifiers.
This study is based on an analysis of all Part B claims, including DMEPOS claims, with GA, GZ, GX, and GY modifiers for calendar year 2011. It is also based on structured interviews with staff at CMS and selected claims processing contractors.
Analysis of Part B claims. Using CMS’s National Claims History File and Standard Analytical File, we analyzed all Part B claims with GA, GZ, GX, or GY modifiers from 2011.15 We determined the number of claims with each of these modifiers, the number and percentage of these claims that Medicare paid, and the total amount Medicare paid for these claims. We also analyzed the services or items that were billed on these claims.
We determined the types of services or items that had the largest numbers of paid claims and the amounts Medicare paid for each of these services or items.
Next, we analyzed the number of paid claims that included inappropriate combinations of G modifiers. We did this analysis for all Part B claims with GA, GZ, GX, or GY modifiers from 2002 to 2011. We looked for combinations that represent inappropriate scenarios, such as when one modifier indicates that a service or item is not reasonable and necessary and the other modifier indicates that Medicare does not cover the service or item. For the purposes of this report, we use “providers” to refer to both providers and suppliers.
Interviews with CMS staff and selected contractors. We conducted structured interviews with staff at CMS and selected claims processing contractors about how they use G modifiers. We also asked staff at each contractor whether they have any laimsprocessing edits specific to claims with G modifiers and under what circumstances they review these claims. During the period of our review, CMS was transitioning the claims processing workload of other contractors, called carriers, to the MACs. For this review, we interviewed staff at the 13 MACs; these contractors processed 78 percent of all paid 2011 claims with G modifiers.16 We conducted these interviews in September 2011.
This inspection was conducted in accordance with the Quality Standards for Inspection and Evaluation approved by the Council of the Inspectors General on Integrity and Efficiency.