Impairment evaluation requires medical knowledge; therefore, mostly doctors who are qualified in allopathic or osteopathic medicine or chiropractic medicine use the Guides to evaluate permanent impairment. For the purpose of determining impairment, the appropriate health regulatory agency in a given jurisdiction is the best-suited authority to determine the definition of doctor in regard to who uses the Guides to rate impairment in that jurisdiction.
It must be emphasized, however, that even though the Guides is mainly written by medical doctors for medical doctors and others permitted to do impairment evaluations, non-physician evaluators may analyze an impairment evaluation to determine if it was performed in accordance with the Guides.
The accurate use of the Guides requires a fundamental understanding of anatomy, physiology, pathology, and other appropriate clinical sciences along with a good understanding of the issues related to impairment and disability assessment. Additionally, the knowledge of key concepts and philosophy underlying the Guides, as outlined in Chapter 1 and here, along with the thorough understanding of the appropriate chapters of the Guides are essential for a credible impairment rating.