Factor structure of the Wechsler Adult Intelligence Scale-revised (WAIS-R): a clinical sample.
Factor analysis was performed on a heterogeneous clinical sample of neurological patients. Both a two- and a three-factor model were extracted. The two-factor solution corresponded to Wechsler's categorization of verbal and performance subtests. The three-factor solution suggested a verbal comprehension factor, a perceptual organization and a third factor with highest loadings on digit span, arithmetic and digit symbol. Both models were consistent with factor models obtained from the standardization sample. As has previously been reported in neurologically impaired samples, the third factor was relatively more prominent than in the standardization sample. This study provides further evidence for the robustness of the WAIS-R factor structure across different populations and gives good support for the use of the WAIS-R in British clinical samples.