This tool provides physicians with a complete relative value scale for developing fee schedules and analyzing contracts. The RBRVS for the Medicare physician fee schedule (MPFS), developed by CMS, is not a complete schedule. By law, Medicare cannot pay for certain services — these services usually are not assigned relative value units (RVUs) by CMS. Codes not valued by Medicare are referred to as “gap codes.” The Essential RBRVS Data File gives you all the codes valued by CMS, as well as relative values for codes not valued by Medicare.