Confirmatory factor analysis of the Wechsler Memory Scale-Revised in a sample of head-injured patients

As part of a standard evaluation of neuropsychological sequelae, the Wechsler Memory Scale-Revised (WMS-R) was administered to 107 patients with a history of traumatic brain injury. Confirmatory factor analyses were conducted on the 12 subtests of the WMS-R to examine the fit of various hypothesized factor patterns, including patterns identified in previous exploratory factor analytic studies. Because part of the correlation between immediate and delayed recall trials of the same material is attributable to a common measurement procedure, this correlation due to measurement commonality was partialled out of the conceptual factor structure. The results suggested the presence of 3 distinct but highly correlated factors: attention/concentration, immediate memory, and delayed recall. Models that posited separate verbal and nonverbal memory processes failed to improve fit over more parsimonious models. Comparisons with previous factor analytic studies and implications for clinical assessment are discussed.