Independent examination of the Wechsler Adult Intelligence Scale-Fourth Edition (WAIS-IV): what does the WAIS-IV measure?
Published empirical evidence for the Wechsler Adult Intelligence Scale-Fourth Edition (WAIS-IV) does not address some essential questions pertaining to the applied practice of intellectual assessment. In this study, the structure and cross-age invariance of the latest WAIS-IV revision were examined to (a) elucidate the nature of the constructs measured and (b) determine whether the same constructs are measured across ages. Results suggest that a Cattell-Horn-Carroll (CHC)-inspired structure provides a better description of test performance than the published scoring structure does. Broad CHC abilities measured by the WAIS-IV include crystallized ability (Gc), fluid reasoning (Gf), visual processing (Gv), short-term memory (Gsm), and processing speed (Gs), although some of these abilities are measured more comprehensively than are others. Additionally, the WAIS-IV provides a measure of quantitative reasoning (QR). Results also suggest a lack of cross-age invariance resulting from age-related differences in factor loadings. Formulas for calculating CHC indexes and suggestions for interpretation are provided.
Benson
Nicholas
N
Division of Counseling and Psychology in Education, The University of South Dakota, Vermillion, SD 57069, USA. nicholas.benson@usd.edu
Hulac
David M
DM
Kranzler
John H
JH
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000523:psychology*; D000704:Analysis of Variance; D005260:Female; D006801:Humans; D008297:Male; D008606:Mental Processes; D008875:Middle Aged; D015233:Models, Statistical; D011594:Psychometrics / Q000706:statistics & numerical data; D012016:Reference Values; D015203:Reproducibility of Results; D014888:Wechsler Scales / Q000706:statistics & numerical data*; D055815:Young Adult