Coding Interpretations: One-on-One and the Group Code

September 2002: Concerns have been raised regarding the delivery of outpatient physical therapy services within the Medicare program, specifically regarding the appropriate use of a one-on-one code as opposed to the group code.

APTA supports the interpretation of the group therapy code for outpatient physical therapy services, as established by the Centers for Medicare and Medicaid Services (CMS) and as clarified in the Carriers Manual Transmittal 1753. This longstanding policy states that outpatient physical therapy services provided simultaneously to two or more individuals by a practitioner constitutes group therapy services and should be billed as such. The individuals can be, but need not be performing the same activity. The therapist involved in group therapy services must be in constant attendance and must provide skilled services to the group.

Furthermore, APTA supports the interpretation of the one-on-one codes as published by CMS.

While APTA agrees with the CMS interpretations of the one-on-one and the group codes, we strongly urge CMS to take the necessary steps to ensure that the group code be properly recognized for reimbursement when it is used appropriately. As many as half of CMS contracted payers do not recognize the 97150 code or will not pay for it with one-on-one procedures billed on the same date. APTA also firmly requests that CMS revisit the calculation of the indirect practice expense as applied to physical therapists.


Language describing the appropriate use of one-on-one codes and the group code first appeared in the Federal Register in 1994 (12-8-94, Vol 59, No 235, p 63451). This same language was republished in the Federal Register in 1996 (11-22-96, Vol 61, No 227, p 59542). CMS further clarified usage of the group code in Carriers Manual Transmittal 1753, dated May 17, 2002. The language in the transmittal states:

Group Therapy Services (Code 97150)

Pay for outpatient physical therapy services (which includes speech-language pathology services) and outpatient occupational therapy services provided simultaneously to two or more individuals by a practitioner as group therapy services. The individuals can be, but need not be performing the same activity. The physician or therapist involved in group therapy services must be in constant attendance, but one-on-one patient contact is not required. 

The CPT Code 97150 [Therapeutic Procedure(s), group, (2 or more individuals)] can be applied to different situations. In one situation, the physical therapist, or physical therapist assistant under the direction and supervision of a physical therapist, is simultaneously treating two or more patients whose conditions or treatment have a common, unifying element. For example, the patients might all have had knee surgery; or they might all benefit from specific types of pool exercises; or they might all be part of a class for people waiting to be fitted for lower limb prostheses. The physical therapist might provide some introductory instruction and would remain in attendance for the duration of the session for which a group code was billed. 

Another situation involves two or more patients whose conditions or treatments do not have a common unifying element. In this situation, the patients could have diverse conditions and be receiving diverse treatments as part of a group to which the physical therapist gives constant attendance and provides differing, but skilled, services in accord with his or her professional judgment. For example, two or more patients might receive one-on-one treatment for their individual conditions (but never at the same time) from a physical therapist, and also these patients may then perform, in each other's company, individualized exercise routines prescribed by the physical therapist specifically as part of each patient's plan of care. During the period in which these patients are exercising simultaneously, the physical therapist meets the requirement of constant attendance by providing clinical expertise and judgment, such as offering feedback, providing further individualized instruction, implementing modifications and progressions of the exercise program for each patient, or measuring each patient's response to treatment.

APTA recognizes that in the above situations it may be possible to add the time spent with each individual patient and bill for these services with an appropriate one-on-one code when the one-on-one time requirements are met. This also may be the most efficient approach. However, APTA also supports the interpretation that would allow these professional services to be billed under the group code, which is an untimed code, all other requirements for professional services having been met.

The duration of the group session to which the code is applied should be sufficient to ensure that professional ("skilled") services are provided. Because the code is not a timed code, it can be used with other interventions provided on the same day of services, although modifiers may be required.

Lastly, APTA does not interpret Transmittal 1753 as prohibiting payment for a supervised (unattended) modality and a one-on-one service being delivered to two patients in the same time interval. For example, Patient A is receiving unattended electrical stimulation at the same time as patient B is receiving therapeutic exercise.

[Last updated: 07/17/09 | Contact:]


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