Receiving Medicare Reimbursements with Modifier AT

Need for Active Treatment (AT) Modifier

The Centers for Medicare & Medicaid Services (CMS) developed the Active Treatment (AT) modifier to define the difference between active treatment and maintenance treatment. Medicare only pays for active/corrective treatment to correct acute or chronic subluxation. Medicare never pays for maintenance therapy. In 2018, the Medicare Fee-for-Service program reported 41 percent improper payments for chiropractic services. Medicare used the Comprehensive Error Testing Program (CERT) to measure improper payments for chiropractic services. Most of those errors were due to insufficient documentation or documentation errors. Year after year these error rates appear. CMS is providing an explanation of the AT modifier to help providers document claims correctly for chiropractic services they provide to Medicare beneficiaries. Let’s have a detailed understanding of modifier AT which will help in receiving Medicare reimbursements.

As mentioned above, the AT modifier is created to differentiate between active treatment and maintenance treatment. The AT modifier is required on Medicare claims to receive reimbursement for CPT codes ranging from 98940-98942. While billing Medicare, chiropractors should use the AT modifier only when billing for active/corrective treatment (acute and chronic care). You can’t use the AT modifier for maintenance therapy.

Coverage of Treatment

The following categories help determine coverage of treatment:

  • Acute subluxation: A patient’s condition is considered acute when the patient is being treated for a new injury (identified by x-ray or physical examination). The result of chiropractic manipulation is expected to be an improvement in, or arrest of the progression of, the patient’s condition.
  • Chronic subluxation: A patient’s condition is considered chronic when it is not expected to significantly improve or be resolved with further treatment (as is the case with an acute condition); however, continued therapy can be expected to result in some functional improvement. Once the clinical status has remained stable for a given condition, without the expectation of additional objective clinical improvements, further manipulative treatment is considered maintenance therapy and is not covered.

Medicare covers the above scenarios while there is an active treatment that you document correctly and you expect the patient to improve. As stated in the Medicare Benefit Policy Manual, Chapter 15, Section 240, the doctor of chiropractic should be afforded the opportunity to effect improvement or arrest or retard deterioration in such condition within a reasonable and generally predictable period of time. Acute subluxation (for example, strains or sprains) problems may require as many as three months of treatment but some require very little treatment.

In the first several days, treatment may be quite frequent but decrease in frequency with time or as improvement is obtained. Chronic spinal joint condition implies, of course, the condition has existed for a longer period of time and that, in all probability, the involved joints have already “set” and fibrotic tissue has developed. This condition may require a longer treatment time, but not with higher frequency.

Maintenance therapy includes services that seek to prevent disease, promote health and prolong and enhance the quality of life, or maintain or prevent deterioration of a chronic condition. When further clinical improvement cannot reasonably be expected from continuous ongoing care, and the chiropractic treatment becomes supportive rather than corrective in nature, Medicare considers the treatment is maintenance therapy. As mentioned above, do not use the AT modifier when you provided maintenance therapy.

Receiving Medicare Reimbursements

For receiving Medicare reimbursements with modifier AT, ensure that you are adhering following billing guidelines:

  • The claim should include a primary diagnosis of subluxation and a secondary diagnosis, reflecting the patient’s neuromusculoskeletal condition. The patient’s medical record should support the services you are billing. You can refer to MLN Matters Article SE1601 for a detailed understanding of medical record documentation requirements.
  • Chiropractors should consider obtaining an Advance Beneficiary Notice (ABN) from beneficiaries in the event of a denial of a claim.
  • Be aware that once the provider cannot determine there is any improvement, treatment becomes maintenance and Medicare no longer covers the treatment.
  • Chiropractors must place an AT modifier on a claim when providing active/corrective treatment to treat acute or chronic subluxation. However, the presence of the AT modifier may not in all instances indicate that the service is reasonable and necessary. As always, MACs (Medicare Administrative Contractors) may deny the claim if a medical review determines that the medical record does not support active/corrective treatment.
  • Be aware of billing guidelines along with any Local Coverage Determinations (LCDs) for chiropractic services in your area that might limit circumstances under which Medicare pays for active/corrective chiropractic services.

We hope that the above article will help you in receiving Medicare reimbursements with Modifier AT, you can check reference links for a detailed understanding. Medical Billers and Coders (MBC) is a leading medical billing company providing complete revenue cycle services. We can assist you in receiving accurate Medicare reimbursements for chiropractic services.

We are well versed with Medicare billing guidelines for chiropractic services and accurately use procedure codes and modifiers. To know more about our chiropractic billing services, email us at: or call us at: 888-357-3226.