You'll be bringing yourself to CMS's attention if you fail to respond to Comprehensive Error Rate Testing medical review requests. CMS staff will be making calls to providers that haven't responded to CERT requests for medical review, contractors Cahaba GBA and Palmetto GBA say on their websites. "Although you may have already received letters and telephone calls from the CERT contractor, these additional efforts by CMS to obtain adequate documentation may change your claim's status from 'improper payment' to 'proper payment,'" they say. "This will allow us to calculate a more accurate Medicare FFS error rate, while also reducing the amount of improper payments."