When billing for the Chiropractic adjustment and non-covered services,
modifiers are a must. When billing 98940, 98941 and 98942, the "AT"
modifier is necessary to tell the Medicare carrier - this is "active
treatment" and to consider payment for this service. This does not
mean they will automatically pay. If the doctor, after making an assessment of the patient each and
every visit, believes Medicare may not pay for this covered service
he may ask the patient to sign an ABN. All payable services 98940,
98941 or 98942 will be followed by "AT" and "GA" modifiers.
The lack of "AT" modifier after a payable service means the doctor is
asking the Medicare Carrier to consider this service as a nonpayable
service and telling the carrier NOT to pay. That is usually a mistake
because the adjustment to correct a subluxation is the only thing
The doctor also needs to learn to document so the
covered services in Medicare are reimbursed.
The "GX" modifier is only used when non-covered services are billed to
Medicare. This is done to receive a denial EOB for supplemental