On WAIS—R difference scores in a psychiatric sample.

This report examines the psychometric integrity of the Wechsler Adult Intelligence Scale—Revised (WAIS—R) subscales, and the differences between them, in a sample of 229 psychiatric patients from 2 community mental health centers (ages 16 to 85). The results verify the overall alpha and split-half reliabilities of the instrument and indicate that greater caution needs to be exercised in clinically evaluating difference scores. Cutoff values presented in the manual appear too low to be of any statistical or diagnostic merit. Distributions for each of the 55 possible difference scores found in this sample are presented and provide a better guide for making nosological determinations. (PsycINFO Database Record (c) 2010 APA, all rights reserved)