| LT | Left Side – Used to identify procedures performed on the left side of the body. No effect on payment; however, failure to use when appropriate could result in delay or denial (or partial denial) of the claim. |
| RT | Right Side – Used to identify procedures performed on the right side of the body. No effect on payment; however, failure to use when appropriate could result in delay or denial (or partial denial) of the claim. |
| 26 | Professional component only – Certain procedures are a combination of a physician component and a technical component. When the physician component is reportedly separately, the service may be identified by adding the modifier –26 to the usual procedure number. The fee schedule contains different payment amounts for professional components. Affects payment. |
| 90 | Reference lab – Used to indicate a lab test sent to a referral (outside) lab, e.g., lab procedure performed by a party other than the treating or reporting laboratory. Note: Referral lab name, address and/or PIN must be included with the claim. No effect on payment. |
| 91 | Repeat clinical diagnostic laboratory test – In the course of treatment of the patient, it may be necessary to repeat the same laboratory test on the same day to obtain subsequent (multiple) test results. Under these circumstances, the laboratory test performed can be identified by its usual procedure code and the addition of the modifier -91. Note: This modifier may not be used when test are rerun to confirm initial results; due to testing problems with specimens or equipment; or for any other reason when a normal, one-time, reportable result is all that is required. This modifier may not be used when other code(s) describe a series of test results (e.g., glucose tolerance test, evocative/suppression testing). This modifier may only be used for laboratory test(s) performed more than once on the same day on the same patient. |
| QP | Panel test – Documentation is on file showing that the laboratory test(s) was ordered individually or ordered as a CPT-recognized panel other than automated profile codes. No effect on payment, but may assist with medical necessity determinations. |
| QW | CLIA Waived Test – Effective October 1, 1996, all new waived tests are being assigned a CPT code (in lieu of a temporary five-digit G- or Q-code). The CPT code should be billed with a modifier QW by entities holding a Certificate of Waiver. |
| TC | Technical component only – Use to indicate that the technical component is reported separately (from the professional component) for the diagnostic procedure performed. The fee schedule contains different payment amounts for technical components. Affects payment. |
Pathology Billing Company. Data Management, Inc. http://www.dmimd.com