John Blaha

Hierarchical Factor Structure of the Wechsler Intelligence Scale for Children

A Wherry-Wherry (1969) hierarchical factor analysis was performed on WISC subtest intercorrelations reported by Wechsler (1949). An hierarchical ability arrangement congruent with Vernons (1950) structural paradigm was obtained. A strong general factor (g) was defined by positive loadings from all subtests and two relatively weak subgeneral factors; a subgeneral factor corresponding to Vernons (1950) verbal-educational (v:ed) factor was defined by the verbal subtests and another by the performance sub-rests. The latter seemed to correspond to the spatial-perceptual (k:m) factor of Vernons (1950) paradigm. These data not only provided strong support for the construct validity of the WISC as a measure of g but also provided some conditional support for Wechslers (1949) decision to maintain separate verbal and performance IQs.

Hierarchical Factor Structure of the Wechsler Intelligence Scale for Children--III.

R. J. Wherry and R. J. Wherry (1969) hierarchical factor solutions were obtained on the Wechsler Intelligence Scale for Children-III intercorrelations reported in the standardization sample (D. Wechsler, 1991). Two- and 4-factor solutions were obtained for the 6-7, 8-10, 11-13, and 14-16 age levels. Both solutions indicated a strong general intelligence (g) factor at all 4 age levels. At the primary level, factors corresponding to the verbal-numerical-educational and spatial-mechanical-practical dimensions from Vernons (1950) paradigm emerged when a 2-factor solution was used. When a 4-factor solution was used, Perceptual Organization, Perceptual Speed, Verbal Comprehension, and Freedom From Distractibility factors were obtained at the primary level.

The Hierarchical Factor Structure of the WISC-R for Learning Disabled Children.

A Wherry and Wherry (1969) hierarchical factor solution was performed on the 12 WISC-R subtest intercorrelations for a sample of 85 learning disabled children. A hierarchical ability structure similar to, though not congruent with, Vernons (1950) paradigm was obtained. The hierarchy included a general (g) factor and three subgeneral factors consisting of an intact spatial-perceptual-mechanical (k:m) factor, a verbal comprehension factor, and a freedom-from-distractibility factor. The factor structure of learning disabled children was somewhat more fractionated and complex than that for normals, but not as complex as the structure of reading disabled children. This suggests that the more severe a learning disability, the greater the difference between the hierarchical factor structure for that group and the factor structure of normals.

Developing Remedial Hypotheses from Ability Profiles

I n an earlier article (Vance, Wallbrown, & Blaha 1978), the results of a profile analysis of the Wechsler Intelligence Scale for Children — Revised (WISC-R) subtest scores for reading disabled children were described. The analysis was concerned only with profile shape, since level and dispersion were controlled through a selection of the students included in the study. Level was controlled to some extent by excluding those students with Full-Scale WISC-R IQs less than 85. Dispersion was controlled by excluding students who failed to show an appreciable variability in their WISC-R profiles from the study. The original sample consisted of 128 children, but 24 were not included in this study because their WISC-R profiles were relatively flat, or showed minimal dispersion. An analysis of the WISC-R profiles for the 104 children remaining in the sample showed five ability patterns that can be used to help develop remedial strategies. The five profiles obtained in the analysis were Distractibility, Perceptual Organization, Language Disability-Automatic, Language Disability-Pervasive, and Behavioral Comprehension and Coding. Most students (75

Note on the construct validity of the multidimensional aptitude battery

) had WISC-R profiles that showed considerable similarity to one of these ability patterns (syndromes). The profiles of some students (14

Hierarchical analyses of the WISC and WISC-R: synthesis and clinical implications

) tended to split evenly between syndromes or showed only minimal similarity to any of the five syndromes. These findings suggest that WISC-R

Information processing components of Koppitz errors on the Bender Visual-Motor Gestalt Test.

A Wherry-Wherry (1969) hierarchical factor solution was obtained for the intercorrelations among subtests of the Multidimensional Aptitude Battery for a sample of 3,121 high school students reported by Jackson (1984). An hierarchical arrangement of abilities consisting of a strong g-factor and two primaries corresponding to the verbal-education (v.ed) and spatial-perceptual-mechanical (k:m) parameters from Vernons 1950 structural model were obtained. This ability arrangement provides construct validity for the Full Scale IQs, Verbal IQs, and Performance IQs from the Multidimensional Aptitude Battery.

The hierarchical factor structure of the WAIS-R for alcoholic adults.

A review of hierarchical factor solutions obtained on normal and atypical samples in twelve previous studies showed ability arrangements in agreement with Vernons structural paradigm. A composite hierarchy synthesized from these studies includes a general intelligence (g) factor at the apex and major group factors corresponding to the verbal-educational (wed) and spatial-mechanical-practical (kim) dimensions at the subgeneral level. Verbal Comprehension (VC), Freedom from Distractibility (FD), Spatial (k) and Quasi-Specific (QS) minor group factors comprised the third level of the ability hierarchy. Four principles are suggested as guidelines for the clinical interpretation of the WISC-R.

A Reply to Miller's Concerns about WISC-R Profile Analysis:

Correlated performance and latencies on the Bender, Matching Familiar Figures Test and Draw-a-Person along with the Slosson Intelligence Test for 39 male and 35 female middle-class black first graders. The results suggest that the Bender may owe much of its clinical validity to loadings across all stages of human information processing. General intelligence accounted for 9% of Bender variance. With the higher order variable intelligence partialed out, the preprocessing and central processing stages accounted for 16% and the response selection and response execution stages accounted for 6% of Bender variance. Kagans hypothesis with retard to the involvement of conceptual tempo in Bender performance was not supported. However, Kagans contention that impulsivity is measured only in situations with high response uncertainty did receive some support.

The Hierarchical Factor Structure of the WISC and Revised ITPA for Reading Disabled Children.

A Wherry (1984) hierarchical factor solution was obtained on the WAIS-R subtest intercorrelations for 108 alcoholic adults. An ability arrangement consistent with Vernons (1950) structure-of-intellect paradigm was found. This ability hierarchy consisted of a strong general intelligence (g) factor defined by all 11 subtests, which accounted for 49% of the variance. The primary level of the ability hierarchy consisted of spatial-perceptual-mechanical (k:m), Freedom from Distractibility (FD), and Verbal Comprehension (VC) factors. Those respective factors accounted for 86%, 4%, and 3% of the total subtest variance.