Relative usefulness of the WMS and WMS-R: a comment on D'Elia et al. (1989).

In a previous commentary, D'Elia and colleagues reflected on the relative adequacy of normative data for the original Wechsler Memory Scale (WMS) and the Wechsler Memory Scale-Revised (WMS-R). They concluded that, for some age groups, the original version of the test is preferred. We discuss further the crux of the D'Elia and colleagues criticism of the WMS-R, namely the issue of interpolation in tables of normative data. We also consider two additional criteria: the sampling techniques used to obtain the normative samples, and the respective standard errors of measurement and scaling properties of scores on the two tests. We conclude that on each of these criteria the WMS-R is preferable.