Base rates of intersubtest scatter in the old age standardization sample of the WAIS-R

Abstract

The Wechsler Adult Intelligence Scale-Revised (WAIS-R) old-age standardization sample was analyzed to ascertain normal base rates of intersubtest scatter. The range and number of scaled scores that deviated by +/- 3 points from the mean were calculated for each subject on the Verbal, Performance, and Full Scale subtests. Mean ranges for the total sample were 4.4, 3.4, and 6.5, respectively. Ranges were larger for men than women; whites demonstrated more scatter than blacks. An increase in scatter emerged on the Verbal and Full Scales as one moved from the lowest to the highest education and IQ groups. Over 75% of individuals had two, one, or zero subtests that deviated significantly from their WAIS-R mean score. Finally, the scatter range for the elderly sample was compared to the original WAIS-R standardization sample.