The following Comprehensive Error Rate Testing (CERT) errors occurred during the most recent reporting period within the states of Illinois, Michigan, Minnesota, and Wisconsin. The CERT Error Analysis web page details the errors found for Clinical Laboratory - Specialty 69. Insufficient Documentation: Missing acceptable physician order (illegible signature) and progress notes (no beneficiary name, illegible signature) to support medical necessity for the laboratory tests billed. Medically Unnecessary Service or Treatment: Missing physician’s order and/or the electronic order protocol to support the E-Requisition submitted. Service Incorrectly Coded: Progress notes support medical necessity and intent to order a CBC and not a CBC with differential as billed and the results reported.