Medically Unlikely Edits (MUEs) are either claim line edits or date of service (DOS) edits. If the MUE is a claim line edit, each line of a claim is adjudicated against the MUE value for the Healthcare Common Procedure Coding System (HCPCS)/Current Procedural Terminology (CPT) code on that claim line. If the units of service (UOS) on the claim line exceeds the MUE value, all UOS for that claim line are denied. If the same code is reported on more than one line of a claim by using CPT modifiers, each line of the claim is adjudicated separately against the MUE value of the code on that claim line.
If the MUE is a date of service MUE, all UOS for the HCPCS/CPT code reported by the same provider for the same beneficiary for the same date of service are summed. The summed value is compared to the MUE value. If the sum is greater than the MUE value, all UOS for the code on the current claim are denied.