In passing the Bipartisan Budget Act of 2018, Congress required that by January 1, 2019, the Centers for Medicare and Medicaid Services establish a modifier to indicate when an outpatient physical therapy service is furnished in whole or in part by a physical therapist assistant.

Starting January 1, 2022, outpatient physical therapy services covered under the Medicare physician fee schedule that are furnished at least in part by a PTA will be paid at 85% of the applicable fee schedule rate. (A similar modifier was designated for services provided by an occupational therapy assistant, which also will be subject to the 85% payment differential).

So that providers are prepared for 2022, use of the modifier was mandated as of January 1, 2020, for outpatient therapy providers across almost all settings — including private practices, skilled nursing facilities, home health agencies, outpatient hospitals, rehabilitation agencies, and comprehensive outpatient rehabilitation facilities. The modifier is CQ for PTAs (CO for OTAs).