Short-term practice effects in mild cognitive impairment: Evaluating different methods of change

ABSTRACT

Practice effects are improvements on cognitive tests as a result of repeated exposure to testing material. However, variability exists in the literature about whether patients with amnestic mild cognitive impairment (MCI) display practice effects, which may be partially due to the methods used to calculate these changes on repeated tests. The purpose of the current study was to examine multiple methods of assessing short-term practice effects in 58 older adults with MCI. The cognitive battery, which included tests of memory (Hopkins Verbal Learning Test–Revised and Brief Visuospatial Memory Test–Revised) and processing speed (Symbol Digit Modalities Test and Trail Making Test Parts A and B), was administered twice across one week. Dependent t tests showed statistically significant improvement on memory scores (ps < .01, ds = 0.8–1.3), but not on processing speed scores. Despite this, the sample showed no clinically meaningful improvement on any cognitive scores using three different reliable change indices. Regression-based change scores did identify relatively large groups of participants who showed smaller than expected practice effects, which may indicate that this method is more sensitive in identifying individuals who may portend a declining trajectory. Practice effects remain a complex construct, worthy of continued investigation in diverse clinical conditions.

KEYWORDS:

• Cognitive change
• Memory
• Mild cognitive impairment
• Practice effects
• Reliable change index

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

The project described was supported by research grants from the National Institutes on Aging [grant number 5R01AG045163]; and NCATS/NIH [grant number 8UL1TR000105 (formerly UL1RR025764)]. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institute on Aging or the National Institutes of Health.