CONFIRMATORY FACTOR-ANALYSIS OF THE WECHSLER MEMORY SCALE-REVISED STANDARDIZATION SAMPLE

A maximum likelihood confirmatory factor analysis was preformed by app lying LISREL to the variance-covariance matrix obtained from standardi zation of the Wechsler Memory Scale-Revised (WMS-R) (N = 316). Analyse s were designed to determine which of seven hypothesized factor soluti ons could best explain memory function as measured by the WMS-R. Compe ting latent variable models were identified in previous exploratory an d confirmatory factor analytic studies. The measurement error matrix w as set to remove method variance shared by the immediate and delayed t rials of the same subtest. Hypothesized factors were fixed and allowed to correlate. Results indicated that a three-factor model, including Attention/Concentration, Immediate and Delayed Memory, explained 91% o f the score variance and produced a significantly better fit than the Attention/Concentration - General Memory or Attention Concentration - Visual/Verbal Memory solutions Findings support previous work suggesti ng that the WMS-R measures separate memory functions, and that the ver bal/nonverbal index distinction may not be a viable one.