The aphasia quotient: the taxonomic approach to measurement of aphasic disability. 1974.

150 aphasiacs and 59 controls were examined with a scorable, comprehensive battery, designed to be used by the clinician and the research worker. The subtests of Fluency, Information, Comprehension, Repetition and Naming were added and compared to a hypothetical normal of 100 obtaining the "aphasia Quotient." This is a measurement of the severity of language impairment. On the basis of their performance on the subtests, the patients were classified according to taxonomic principles into Global, Motor (Broca's), Isolation, Sensory (Wernicke's), Transcortical Motor, Transcortical Sensory, Conduction and Anomic groups (in order of severity). This classification is considered a clinically valid baseline for research, diagnosis and prognosis.