6.6 RETROSPECTIVE REVIEW All claims for services or supplies that the Plan does not require be subject to Precertification, Concurrent (Continued Stay) Review, or Second Medical Opinion Programs may be subject to retrospective review to determine if they were Medically Necessary. If it is determined that the services or supplies were not Medically Necessary, no benefits will be provided by the Plan for those services or supplies. The review procedures from a denial of benefits based on Retrospective Review are the same as those for Precertification Review; see Section 6.5.4.