Three aspects of behavior are independently measured -- motor responsiveness, verbal performance, and eye opening. Other states of conscious may be qualitatively defined.

(New York Times, 2005)

"There are therefor good reasons for restricting routine observations to a minimum, and for chosing those which can be reliably recorded and understood by a range of different staff."

Teasdale, G., & Jennett, B. (1974). Assessment of coma and impaired consciousness: A practical scale. Lancet, 2, 81-84.