WAIS-R marker for dementia of the Alzheimer type? An empirical and statistical induction test.

A specific WAIS subtest pattern has recently been shown to occur more frequently in cases of dementia of the Alzheimer's type (DAT) than in cases of multi-infarct dementia (Fuld, 1984; Brinkman & Braun, 1984). To date, only one study has examined the frequency of this WAIS pattern in a normal elderly sample and found it to be infrequent (Tuokko & Crocket, 1987). If replicated on a larger sample of normals, it would increase the potential of this pattern as a behavioral marker of DAT. WAIS-R scores (age-corrected) were analyzed on a sample of 149 healthy volunteers (ages 60-94) who were part of an ongoing aging study. Because only 12% of the sample revealed this WAIS pattern, its utility as a conditional marker of DAT in three different hypothetical clinical base rate settings was evaluated. Results provided cautious optimism for the application of this marker in certain clinical settings.