Which modifier is used for a lab test that needs to be repeated on the same day for the same patient?

The modifier that is correctly used for a lab test that needs to be repeated on the same day for the same patient is modifier 91. This modifier indicates that a laboratory test was repeated on the same day and is necessary for reporting multiple test results for a single patient within the same encounter. When a lab test needs to be repeated, modifier 91 helps avoid confusion that could arise from submitting the test more than once without clarification.

In the context of coding and billing, it is crucial to accurately document tests that are repeated to ensure proper reimbursement and to inform payers that the repeated tests are warranted based on the patient's condition.

Modifiers such as 25, 76, and 58 serve different purposes in medical coding. Modifier 25 is used to signify a significant, separately identifiable evaluation and management service performed on the same day as a procedure. Modifier 76 indicates a repeat procedure by the same physician or provider. Modifier 58 is used to denote a staged or related service that occurs after the original procedure but not on the same day. Each of these modifiers denotes a different situation and does not apply to the specific scenario of repeating a lab test on the same day.