CMS calculates the Medicare Fee-for-Service (FFS) improper payment rate through the Comprehensive Error Rate Testing (CERT) program. Each year, CERT evaluates a statistically valid random sample of claims to determine if they were paid properly under Medicare coverage, coding, and billing rules. Novitas enhanced the CERT Claim Identifier (CID) look up tool to provide current, detailed information about your CERT review. The tool now shows you the dates the medical records were requested and received by CERT. In addition, it shows you the date additional documentation was requested and received. Error codes and status descriptions now have detailed information that you can view by hovering your mouse over the question mark next to the code or status. They now update the CERT data every two weeks so you have the most current information available about your claim.