Dimensions of adult self-concept

A 70-item adjective checklist was administered to four groups of adults as part of a longitudinal study of psychosocial change during four normative transitions. Data gathered at two times with a five-year interval were cluster analyzed separately. Six clusters were extracted from the first set of data, 7 from the second, with minor changes in dimensionality: all 6 original clusters had counterparts in the second analysis, but some dimensional change was seen in all but one cluster. The argument is made that although such dimensional change is often treated as error or completely ignored in longitudinal research, this inattention can lead to serious problems in the interpretation of results.