ABSTRACT
A majority of current research designed to inform us about the older population focuses on individual differences. In these studies, it is typical to obtain data from a sample that represents the older population in total or in part. It also is common in such studies to adopt and/or adapt theories previously tested on samples of younger and middle-aged adults—or on the adult population as a whole—and to determine the degree to which those theories also are able to explain individual differences among older adults.
