Factor Structure of the WAIS-R Italian Version Compared with American and British Solutions

Abstract

The WAIS-R was administered to a sample of 180 young Italian adults (aged 19 to 35 years). A principal components analysis was conducted on the 11 subtests to investigate the factor structure. According to the criteria of extraction, one- and three-factor solutions are discussed. The oblique rotation provided evidence for three correlated factors, 1: Verbal, 2: Perceptual Organization, and 3: Freedom from Distractibility. However, to compare Italian results with those obtained in the USA and UK, an orthogonal rotation was performed. High coefficients of congruence point to similarity of factor loading matrices in all three countries.

Gender differences in latent cognitive abilities and education links with g in Italian elders

“…This three-factor structure of the WAIS-R allowed the picture arrangement subtest to load on both VC and PO factors. Our results are similar to those obtained by Crawford, Allan, Stephen, Parker, and Besson (1989), Burgess, Flint, and Adshead (1992), Laicardi et al (1996), and Pezzuti et al (2012). Table 2 shows descriptive statistics (mean and SD) for each WAIS-R subtest and full score IQ (FSIQ) partitioned on the basis of gender and years of schooling of subjects.…”

“…The three-factor solution was composed of verbal comprehension (VC), perceptual organization (PO), and memory/freedom from distractibility (M/FD) factors whereas the two-factor solution contained the VC and PO factors. A similar three-factor solution was found for an independent sample of 180 young adults aged 19-35 years (Laicardi et al, 1996), and a one-factor solution was found in a sample of 523 older adults aged 65-100 years (Balsamo et al, 2010). Another sample of 400 older adults aged 65-100 years replicated the one-factor structure for ages 65-74 years but found three factors at ages 75-100 years (Saggino, Balsamo, Grieco, Cerbone, & Raviele, 2004).…”

“…Fortunately, the Italian WAIS-R has been tested with both exploratory factor analytic (EFA) and confirmatory factor analytic (CFA) methods on data obtained from normative samples as well as with independent samples of adults (Balsamo, Romanelli, & Saggino, 2010;Laicardi, Frustaci, & Lauriola, 1996;Orsini & Laicardi, 1997, 2003. Using the normative sample, Laicardi (1997, 2003) found three factors for ages 16-54 years, two factors for ages 55-64, and one factor for ages 65-84 years.…”

Structure of the Wechsler Adult Intelligence Scale – Revised in the Italian Normal Standardisation Sample

“…In the twofactors model, Information, Vocabulary, Comprehension, Similarities, Arithmetic, and Digit Span load on a verbal factor, whereas Picture Completion, Picture Arrangement, Block Design, Object Assembly, and Digit Symbol load on a nonverbal factor. Still other researchers have found threefactor models to be the most predictive of subtest variability named by Cohen (1957a) as Verbal Comprehension, Perceptual Organisation and Memory/Freedom from Distractibility (Atkinson, Cyr, Doxey, & Vigna, 1989;Burgess, Flint, & Adshead, 1992;Crawford, Allan, Stephen, Parker, & Besson, 1989;Laicardi, Frustaci, & Lauriola, 1996;Parker, 1983;Ryan & Schneider, 1986;Waller & Waldman, 1990). Verbal Comprehension factor is typically considered to be composed of Information, Vocabulary, Comprehension, and Similarities subtests, whereas Perceptual Organisation factor is thought to be composed of Picture Completion, Picture Arrangement, Block Design, and Object Assembly subtests.…”

Factor Analysis of Wechsler Adult Intelligence Scale-Revised in Developmentally Disabled Persons

“…To control for cultural differences, the WAIS-R version was compared with U.S. and U.K. samples, as well as with the Italian normal samples (Laicardi, et al, 1996;Orsini & Laicardi, 1997). Similar to ;he data derived from other pathological samples, albeit obtained with a different method of factor analysis (Swassing, 1979), in this sample the loadings of the subtests on the two main factors extracted reflect the traditional division of Verbal and Performance IQs.…”