title: Personality Trait Differences Between Young and Middle-Aged Adults: Measurement Artifacts or Actual Trends?
abstract: A growing body of research demonstrates that older individuals tend to score differently on personality measures than younger adults. However, recent research using item response theory (IRT) has questioned these findings, suggesting that apparent age differences in personality traits merely reflect artifacts of the response process rather than true differences in the latent constructs. Conversely, other studies have found the opposite-age differences appear to be true differences rather than response artifacts. Given these contradictory findings, the goal of the present study was to examine the measurement equivalence of personality ratings drawn from large groups of young and middle-aged adults (a) to examine whether age differences in personality traits could be completely explained by measurement nonequivalence and (b) to illustrate the comparability of IRT and confirmatory factor analysis approaches to testing equivalence in this context. Self-ratings of personality traits were analyzed in two groups of Internet respondents aged 20 and 50 (n = 15,726 in each age group). Measurement nonequivalence across these groups was negligible. The effect sizes of the mean differences due to nonequivalence ranged from -.16 to .15. Results indicate that personality trait differences across age groups reflect actual differences rather than merely response artifacts.
authors.affiliation: Michigan State University.
authors.forename: Christopher D
authors.initials: CD
authors.lastname: Nye
authors.affiliation: University of Zurich.
authors.forename: Mathias
authors.initials: M
authors.lastname: Allemand
authors.affiliation: University of Texas at Austin.|University of Melbourne.
authors.forename: Samuel D
authors.initials: SD
authors.lastname: Gosling
authors.affiliation: Atof Inc., Cambridge, Massachusetts.
authors.forename: Jeff
authors.initials: J
authors.lastname: Potter
authors.affiliation: University of Illinois, Urbana-Champaign.
authors.forename: Brent W
authors.initials: BW
authors.lastname: Roberts
mesh_terms: D000328:Adult; D000367:Age Factors; D005260:Female; D006803:Human Development / Q000502:physiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D010551:Personality / Q000502:physiology*; D010555:Personality Inventory; D055815:Young Adult