The Journals of Gerontology Series B: Psychological Sciences and Social Sciences 61:P144-P151 (2006)
© 2006 The Gerontological Society of America
Short-Term Variability in Cognitive Performance and the Calibration of Longitudinal Change
Timothy A. Salthouse,
John R. Nesselroade and
Diane E. Berish
Department of Psychology, University of Virginia, Charlottesville.
Recent studies have documented that normal adults exhibit considerable variability in cognitive performance from one occasion to another. We investigated this phenomenon in a study in which 143 adults ranging from 18 to 97 years of age performed different versions of 13 cognitive tests in three separate sessions. Substantial within-person variability was apparent across 13 different cognitive variables, and there were also large individual differences in the magnitude of within-person variability. Because people differ in the amount of short-term variability, we propose that this variability might provide a meaningful basis for calibrating change in longitudinal research. Correlations among the measures of within-person variability were very low, even after we adjusted for reliability, and there was little evidence that increased age was associated with a larger amount of within-person variability.
Copyright © 2006 by The Gerontological Society of America.