A carrier may not use a physician rating system unless the physician rating system is approved by a ratings examiner. A carrier shall contract with and pay for a ratings examiner to review any physician rating system of the carrier. A physician rating system of a carrier is deemed to meet the requirements of this section if the physician rating system: is approved by a ratings examiner as of January 1, 2010; and notwithstanding any revisions to the physician rating system, maintains its approval by the ratings examiner.