title: Incremental criterion validity of WAIS-IV factor index scores: relationships with WIAT-II and WIAT-III subtest and composite scores.
abstract: The present study examined the incremental validity of Wechsler Adult Intelligence Scale-4th Edition (WAIS-IV; Wechsler, 2008a) factor index scores in predicting academic achievement on the Wechsler Individual Achievement Test-2nd Edition (WIAT-II; Psychological Corporation, 2002a) and on the Wechsler Individual Achievement Test-3rd Edition (WIAT-III; Wechsler, 2009a) beyond that predicted by the WAIS-IV Full Scale IQ (FSIQ). As with previous intelligence test incremental validity studies, the WAIS-IV FSIQ accounted for statistically significant and generally large portions of WIAT-II and WIAT-III subtest and composite score variance. WAIS-IV factor index scores combined to provide statistically significant increments in variance accounted for in most WIAT-II and WIAT-III subtest and composite scores over and above the FSIQ score; however, the effect sizes ranged from trivial to medium as observed in investigations with other intelligence tests (i.e., Glutting, Watkins, Konold, & McDermott, 2006; Youngstrom, Kogos, & Glutting, 1999). Individually, the WAIS-IV factor index scores provided trivial to small unique contributions to predicting WIAT-II and WIAT-III scores. This finding indicated that the FSIQ should retain primacy and greatest interpretive weight in WAIS-IV interpretation, as previously indicated by WAIS-IV subtest variance partitions form hierarchical exploratory factor analyses (Canivez & Watkins, 2010a, 2012b).
authors: Department of Psychology, Eastern Illinois University, Charleston, IL 61920-3099, USA. glcanivez@eiu.edu
authors: Gary L
authors: GL
authors: Canivez
mesh_terms: D000124:Achievement; D000293:Adolescent; D004521:Educational Measurement / Q000592:standards; D005163:Factor Analysis, Statistical; D005260:Female; D006801:Humans; D008297:Male; D011237:Predictive Value of Tests; D011594:Psychometrics / Q000592:standards*; D015203:Reproducibility of Results; D014888:Wechsler Scales / Q000592:standards*