Relative utility of three indices of neuropsychological impairment in a young, chronic schizophrenic population.

The complete Halstead-Reitan Neuropsychological Test Battery and the Wechsler Adult Intelligence Scale were administered to 20 young, male, chronic schizophrenics. Three commonly used indices of neuropsychological impairment were calculated and compared. Although all three indices were similar in separating computerized axial tomography normal from abnormal patients, statistical significance was achieved only with the Halstead Impairment Index. Thus, the easier-to-obtain Halstead Impairment Index appears to be at least as good as, and possibly better than, the more-difficult-to-obtain indices of Percent of Ratings within the Impaired Range and the Average Impairment Rating. Reasons for these findings are discussed.