Modifier 91 (repeat clinical diagnostic laboratory tests) — Reimbursement Policy
Governs reimbursement for repeat clinical diagnostic laboratory tests billed with Modifier 91 for AMH Health members; applies to providers submitting claims and affects reimbursement and documentation requirements.
07/17/2024, Review approved and effective: no changes.
12/27/2022 review removed the definition from the name of the policy and updated the policy template.
Coverage Criteria for Modifier 91
Coverage criteria for Modifier 91
Covered when ALL of the following are met:
ALL of the following
- Service must be a repeat clinical diagnostic laboratory test performed on the same day for the same member and billed with Modifier 91.
- Reimbursement is at 100% of the applicable fee schedule or contracted/negotiated rate when Modifier 91 is appropriately used.
- Modifier 91 must not be used to repeat a test to confirm initial results, to repeat because of specimen or equipment problems, or when other code(s) describe a series of test results.
- Medical documentation may be requested to support the use of Modifier 91; failure to use the modifier appropriately may result in denial of the repeated laboratory test as a duplicate service.
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