Confirmatory factor analysis of Australian adaptations of combined Wechsler Adult Intelligence ScaleRevised (WAIS-R) and Wechsler Memory Scale-Revised (WMS-R) scores was conducted in a sample of 277 participants undergoing investigation for neurological disorders. The best-fitting model was a six-factor model representing the latent abilities of Verbal Comprehension, Perceptual Organization, Working Memory, Verbal Memory, Visual Memory, and Processing Speed. Invariance of the measurement model was then examined in the mean and covariance structure with data from a recent Australian normative study of the WAIS-R and WMS-R. [Carstairs, J.R. & Shores, E.A. Aust Psychol 35 (2000) 36-40]. Results suggest that the measurement model underlying test scores displayed ''strong'' metric invariance

This study examined the joint factor structure of the Wechsler Adult Intelligence Scale-Revised (D. Wechsler, 1981) and Wechsler Memory Scale-Revised (D. Wechsler, 1987) in a sample of 399 healthy young adults (206 women and 193 men) recruited for a normative study in Sydney, Australia: the Macquarie University Neuropsychological Normative Study. Using confirmatory factor analysis, the authors contrasted alternative models of ability in the respective Wechsler scales, focusing in particular on hypotheses relating to memory function. The best-fitting solution comprised a model representing Verbal Comprehension, Perceptual Organization, Attention-Concentration, Verbal Memory and Visual Memory. The results are discussed in terms of the incremental validity of ability assessment, potential for improvement in model-fit, and implications for professional practice.Psychologists often administer and interpret jointly the scores derived from the Wechsler Adult Intelligence and Memory Scales (Flanagan, Genshaft, & Harrison, 1997;Kaufman, 1990). Research with a variety of ability scales suggests that, like other ability batteries, the Wechsler Intelligence Scales sample important dimensions of cognition . As well, evaluation of long-term or anterograde-memory abilities adds to the explanatory power of models of cognition (Atkinson, 1991;Flanagan & McGrew, 1997).Factor analysis of versions of the Wechsler Intelligence scales has been reviewed often (e.g., Kaufman, 1990;Matarazzo, 1972), most recently in the WAIS-IIIAVMS-III manual (Psychological Corporation, 1997). Many studies suggest that a three-factor oblique solution comprising Verbal Comprehension, Perceptual Organization, and Freedom-From-Distractibility provides the best representation of the abilities measured by the 11 subtest scores. Most recently, with the addition of some new subtests, a fourfactor solution for the WAIS-III has been reported (Psychological Corporation, 1997), adding Processing Speed as a factor to the familiar three factors.

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This study examines the effect of language background on the performance of healthy participants on a battery of cognitive measures. The study was conducted as part of a larger normative study: the Macquarie University Neuropsychological Normative Study (MUNNS). A comparison was made between the test performance of three language background groups: participants from a non-English-speaking background whose first language was other than English (NESB-OE, N = 42); participants from a non-English-speaking background whose first language was English (NESB-E, N = 34); and participants from an English-speaking background (ESB, N = 40). A number of tests used in clinical neuropsychological assessment were found to be sensitive to the background of the participant, and trends in the data suggest that two factors are operating independently. It is proposed that one factor is language or proficiency in English that impacts on verbal subtests and the other is a sociocultural factor that impacts on performance or nonverbal subtests. These findings question current practices when assessing people from non-English-speaking backgrounds

This study examined the joint factor structure of the WAIS-R and WMS-R in a sample of 289 participants (mostly males) with alcohol dependency. In a confirmatory phase we contrasted a range of factor models derived from previous analyses of the Wechsler scales. The best fitting model incorporated five factors representing Verbal Comprehension, Perceptual Organization, Attention-Concentration, Verbal Memory, and Visual Memory, with reassignment of factor loadings for two subtests. The invariance of the measurement model was then examined comparing data from a large sample of healthy participants (J. R. Carstairs & E. A. Shores, 1999). The results indicated that the number of factors was invariant across samples, and four of the factors satisfied the criterion of partial measurement invariance.