An impairment rating is a number expressed as a percentage that is intended to represent the degree of an individual's impairment, which is a deviation away from one's normal health status and functionality. Impairment is distinct from disability. An individual's impairment rating is based on the restrictive impact of an impairment, whereas disability is a broader term that describes the consequences one's impairment. Impairment ratings given to an individual by different medical examiners are sometimes problematically inconsistent with each other.
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Impairment rating Wikipedia(Text) CC BY-SA