A medical percentage that measures permanent loss of bodily function.

"Medical" matters because the rating is usually assigned by a doctor after treatment has stabilized, often at maximum medical improvement. It is not simply a person's own report of pain, and it is not the same as whether someone can return to a job. "Percentage" means the loss is expressed on a scale, such as 5% to a hand or 20% to a back, rather than as a simple yes-or-no disability finding. "Permanent loss of bodily function" focuses on lasting physical or mental limits left after healing, not the temporary symptoms present right after an injury.

In practice, an impairment rating can affect settlement value, ongoing benefits, and disputes about future work restrictions. Insurance carriers, employers, and lawyers may use it when evaluating workers' compensation, permanent partial disability, or the need for continuing care. A higher rating may support greater compensation, but it still does not automatically prove total disability or inability to work.

In North Carolina, impairment ratings are especially tied to workers' compensation under the North Carolina Workers' Compensation Act, N.C. Gen. Stat. § 97-31. After reaching maximum medical improvement, an injured worker may receive a doctor's rating for certain body parts, and that rating can determine compensation for permanent partial disability. If the rating is disputed, the issue may go before the North Carolina Industrial Commission.