Common Working File (CWF) Inquiry

12.7 - Common Working File (CWF) Inquiry (Rev. 4203, Issued: 01-18-19, Effective: 02-19-19, Implementation: 02-19-19) The term Medicare beneficiary identifier (Mbi) is a general term describing a beneficiary's Medicare identification number. For purposes of this manual, Medicare beneficiary identifier references both the Health Insurance Claim Number (HICN) and the Medicare Beneficiary Identifier (MBI) during the new Medicare card transition period and after for certain business areas that will continue to use the HICN as part of their processes. The Common Working File (CWF) maintains the number of counseling sessions rendered to a beneficiary. By entering the beneficiary’s Medicare beneficiary identifier, providers have the capability to view the number of sessions a beneficiary has received for this service via inquiry through CWF.