Which file contains Medicare patient eligibility and utilization data?

The Common Working File (CWF) is the correct choice because it serves as a crucial resource for Medicare administrative functions. This file contains comprehensive information about Medicare beneficiaries, including their eligibility status and utilization of services. It is designed to support the processing of claims and facilitate data sharing between different healthcare providers and payers, ensuring accurate reimbursement and care coordination.

The CWF houses eligibility data that confirms whether a patient qualifies for Medicare benefits, as well as information on what services those patients have accessed. This allows providers to verify eligibility before services are rendered, helping to streamline the billing process and reduce claims denials.

While the Patient Eligibility File and other options may contain relevant data, they do not encompass the full scope of Medicare patient eligibility and utilization data as effectively as the Common Working File does. Thus, the CWF stands out as the primary file used for managing Medicare beneficiaries' eligibility and service utilization.