Wechsler-based CHC cross-battery assessment and reading achievement: Strengthening the validity of interpretations drawn from Wechsler test scores.

Abstract

The Cattell-Horn-Carroll (CHC) cross-battery approach to assessing cognitive abilities has been introduced to the field recently as an alternative to traditional assessment instruments and techniques (Flanagan, McGrew, & Ortiz, 2000; McGrew & Flanagan, 1998). This theory-based method of assessment was developed to provide a more valid and defensible way of deriving meaning from test scores than that provided by the traditional (and largely atheoretical) Wechsler Scale approach. The present study is the first to investigate the validity of the cross-battery approach using a sample of elementary school children (N= 166) who were administered the Wechsler Intelligence Scale for Children-Revised (WISC-R; Wechsler, 1974) and Woodcock-Johnson Psycho-Educational Battery-Revised (WJ-R; Woodcock & Johnson, 1989). Structural Equation Modeling was used to examine whether (a) Wechsler-based CHC cross-battery assessment explained more variance in reading achievement than a traditional Wechsler model, and (b) whether the Wechsler-based CHC cross-battery model provided a more accurate description of the general and specific abilities on general and specific reading achievement than the traditional Wechsler model, as predicted in the extant ^/specific abilities literature. Findings showed that the g factor underlying the Wechsler-based CHC cross-battery model accounted for substantially more variance in reading achievement (25%) than the g factor underlying the atheoretical Verbal Comprehension-Perceptual Organization-Freedom From Distractibility (VC-PO-FFD) Wechsler model. In addition, findings demonstrated that when assessments are organized around the strong CHC theoretical model, specific cognitive abilities, including auditory processing (Ga), crystallized intelligence (Gc), and processing speed (Gs) explained a significant portion of variance in reading achievement beyond that accounted for by g. These