Application of new WAIS-III/WMS-III discrepancy scores for evaluating memory functioning: relationship between intellectual and memory ability.
Analysis of the discrepancy between memory and intellectual ability has received some support as a means for evaluating memory impairment. Recently, comprehensive base rate tables for General Ability Index (GAI) minus memory discrepancy scores (i.e., GAI-memory) were developed using the WAIS-III/WMS-III standardization sample (Lange, Chelune, & Tulsky, in press). The purpose of this study was to evaluate the clinical utility of GAI-memory discrepancy scores to identify memory impairment in 34 patients with Alzheimer's type dementia (DAT) versus a sample of 34 demographically matched healthy participants. On average, patients with DAT obtained significantly lower scores on all WAIS-III and WMS-III indexes and had larger GAI-memory discrepancy scores. Clinical outcome analyses revealed that GAI-memory scores were useful at identifying memory impairment in patients with DAT versus matched healthy participants. However, GAI-memory discrepancy scores failed to provide unique interpretive information beyond that which is gained from the memory indexes alone. Implications and future research directions are discussed.
Lange
Rael T
RT
Riverview Hospital, Coquitlam, British Columbia, Canada. rlange@bcmhs.bc.ca
Chelune
Gordon J
GJ
D000368:Aged; D000369:Aged, 80 and over; D000544:Alzheimer Disease / Q000503:physiopathology*; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D007360:Intelligence / Q000502:physiology*; D007361:Intelligence Tests / Q000706:statistics & numerical data; D008297:Male; D008568:Memory / Q000502:physiology*; D008569:Memory Disorders / Q000209:etiology*; D009483:Neuropsychological Tests / Q000706:statistics & numerical data; D011237:Predictive Value of Tests; D012015:Reference Standards; D015203:Reproducibility of Results; D014888:Wechsler Scales / Q000592:standards* / Q000706:statistics & numerical data*