Cognitive construct measurement in small samples of younger and older adults: An example of verbal working memory

An important issue in experimental aging research is the accurate measureme nt of cognitive constructs, particularly in small-sample studies. Latent va riable modeling approaches to assessing age-based construct similarity are difficult to implement in smaller-scale studies, which tend to have small s amples and measurement of a single construct. We discuss factor score compa rison methods for assessing age-based construct similarity that may be more appropriate for small-scale studies. We then examine these methods for a s eries of single-factor models of verbal working memory (VWM) based on data from three separate studies in which small samples of younger and older adu lts' completed VWM-based tasks. Our single-factor models accounted well for the associations among the sets of VWM tasks. This construct was also meas ured well across age groups and different samples. Our analyses suggest tha t factor score comparison methods may be useful for small-scale studies tha t require assessment of age-based measurement similarity in cognitive const ructs.