Wais versus wais-r subtest patterns: A problem of generalization

Abstract

While the Wechsler Adult Intelligence Scale-Revised (WAIS-R) has gained considerable acceptance as a satisfactory successor to the WAIS as a measure of general intelligence, few studies have examined whether the two tests are comparable in terms of brain-behavior relationships. To evaluate the equivalence of profile interpretations of the WAIS and WAIS-R, the tests were given in a concurrent manner to 43 patients referred for neuropsychological evaluation. While subtest and summary IQ scores were highly correlated, the WAIS-R yielded significantly lower scores than did the WAIS, but not in a uniform manner. Subtest differences ranged from .56 to 2.42, indicating that the WAIS-R introduces a systematic profile bias. Ipsative correlations between profile patterns for each patient ranged from .233 to .986, with a mean correlation of .860. Finally, concordance rates for decisions based on three objective profile rules were examined for the WAIS and WAIS-R data. Concordance rates between tests for “positive” cases ranged from 41.7% to 65.5%. These results suggest that neuropsychological inferences derived from the patterning of WAIS-R subtest scores should be validated empirically and should not be assumed to be comparable with those previously established with the WAIS.