No, it's not a typo! The title of the article is in triplicate to emphasize the definition of Modifier -91, which according to the AMA is "Repeat clinical diagnostic laboratory test." The long description noted in Appendix A of the AMA CPT
1 book states:
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 number and the addition of modifier 91. Note: This modifier may not be used when tests are rerun to confirm the 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 (eg, glucose tolerance tests, 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.
How does Modifier -91 differ from Modifier -59
Modifier -59, which is used for separate and distinct procedures, can also be appended to laboratory tests. With laboratory tests, modifier -59 is used is to identify when a test is performed more than once, but on different specimens. Whereas, Modifier -91 is when the test is being repeated on the same specimen.
What to look for?
- Look for a provider billing modifier -91 when the test describes a series of test results such as CPT 82951 which is a tolerance test (GTT), 3 specimens (includes glucose). If the provider obtained anywhere from 1-3 specimens, then CPT 82951 should be billed once with one unit.2
- Any provider excessively billing for modifier -91. What percentage of their claims show modifier -91?
- Are the claims the result of resubmissions? Do you see prior claims denied and then resubmitted with modifier -91?
- Modifier -91 can only be used with laboratory codes. Is modifier -91 being appended to codes that are not laboratory codes?
- Are providers submitting multiple tests under different IDs to avoid using modifier -91? Providers may try this tactic in order to avoid suspicion if in appropriate billing.
As a reminder, every payer has different clinical as well as reimbursement policies. Some payers request that repeated tests be billed on one claim line with modifier -91 and the appropriate number of units. Other payers want to see each repeated test on their own individual claim line with modifier -91 appended to the second and subsequent claim lines. Refer to your respective organizations to determine what is appropriate for your company.
If you have a question or comment or are interested in learning more about how Healthcare Fraud Shield can help you data mine for modifier -91, contact our subject matter experts at
[email protected].
REFERENCES
1) AMA CPT 2016 Professional Edition, Appendix A
