Effects of practice in repeated administrations of the Wechsler Memory Scale Revised in normal adults.

Practice effects were examined over four administrations of the immediate (I) and delayed (II) portions of three subtests of the WMS-R: Logical Memory (LM), Verbal Paired Associates (VPA), and Visual Reproduction (VR). A repeated measures ANOVA revealed that large and significant (p < .001) increases occurred in the General Memory (GM) and Delayed Recall (DR) indices and in the LMI, LMII, and VPAI subtests (Effect Sizes [ESs] = 0.70-0.87). Small but significant (p < .001) increases occurred in VRI (ES = 0.24) and VRII (ES = 0.43). The greatest increase in scores occurred at the first retest session, whereas increases of smaller magnitudes occurred at Sessions 3 and 4. Ceiling effects occur in subtests (VPAII, VRI, and VRII) on which individuals score most of the total possible points at the first testing session; this makes interpretation of practice effects difficult. Test-retest reliability coefficients, mean change scores from Session 1 to Session 2, standard errors of prediction, and 95% confidence intervals are presented. These score changes need to be taken into consideration when interpreting performance at retest.