Reliable Change Index scores for persons over the age of 65 tested on alternate forms of the Rey AVLT

An issue that often confronts the clinician referred an elderly person for neuropsychological assessment is how to interpret the significance of changes in test scores over time. In this report, data useful for estimating the statistical significance of changes on the Rey Auditory Verbal Learning Test (AVLT) are presented. The sample tested comprised 253 healthy persons aged 65 and over taking part in a randomized double-blind trial of the effect on cognitive performance of lowering homocysteine using dietary supplements. Results were based on the full sample because of the absence of any treatment effects. Test–retest data with a 1-year interval were used to estimate reliability coefficients and to calculate reliable change indices. The magnitude of a change necessary for a deterioration or improvement in scores at the two-tailed 90% confidence interval is given for the full sample, and persons above and below the age of 75.