Factor structure of the wechsler memory scale-revised

The factor structure of the Wechsler Memory Scale-Revised (WMS-R) was examined in a large (N = 434) sample of patients referred to the neuropsychology laboratories of two large medical centers. The subtests of the WMS-R were subjected to principal-components factor analysis. Some analyses included only the immediate-recall subtests, while other analyses included both immediate-and delayed-recall subtests. Additional analyses included VIQ and PIQ from the WAIS-R. Initial analyses of immediate-recall subtests indicated a two-factor solution similar to that reported in the standardization sample. Inclusion of IQ scores also revealed a two-factor solution with IQ scores and most memory subtests loading on separate factors. Inclusion in the analysis of delayed-recall subtests revealed three-factor solution with factors interpreted as representing verbal memory, nonverbal memory, and attention/IQ. These results are discussed in terms of factor-analytic studies of the earlier Wechsler Memory Scale, and the implications of the current data for research and clinical practice.