The computations of the percentage of impairment to the whole person or a member who is awarded a disability benefit are based upon and are in substantial accordance with the American Medical Association's Guides to the Evaluation of Permanent Impairment. The Fifth Edition is utilized for injuries occurring after June 28, 2001. The Fourth Edition is utilized for injuries occurring after November 1, 1993. The Third Edition, Revised is utilized for injuries occurring from January 1, 1989 to October 31, 1993. The Second Edition is utilized for injuries occurring from November 1, 1984 to December 31, 1988. The First Edition is utilized for injuries occurring July 1, 1978 to October 31, 1984.
Okla. Admin. Code § 550:10-1-6