CMS developed the MUE program to reduce the paid claims error rate for Medicare claims. An MUE is a unit of service (UOS) edit for a HCPCS/CPT code for services that a single provider/supplier rendered to a single beneficiary on the same date of service. This CR requires that the shared systems allow a code of "0" be assigned to a HCPCS code for a supply or service that Medicare discontinues. This change is effective Jan 1, 2012. Currently, there are 25 HCPCs codes for which the MUE Workgroup had to assign a default value of "1" in order to account for the code in the set of MUE; the MUEs for those codes will be set to "0" because the drug(s) to which the HCPCs codes were assigned have been discontinued. This represents a significant change to the purpose of MUE’s by extending their use to services that are no longer covered.