Comparing Personality Scales Across Time: An Illustrative Study of Validity and Consistency in Life-Span Archival Data Leslie R. Martin La Sierra University Howard S. Friedman University of California, Riverside ABSTRACT The goals of this study were: (a) to examine whether personality scales, meaningful in contemporary terms, could be derived from archival data; and (b) to use these scales to aid our understanding of the relation of personality to mortality. NEO PI-R data and a battery of archival items, taken from Terman’s Life Cycle Study, were collected on two new samples (sample 1 mean age = 11.9, n = 167; sample 2 mean age = 22.2, n = 203). Measurement invariance of the archival scales was assessed, and validity was examined using both rational analyses and associations with the Five Factor Model. It was demonstrated that Journal of Personality 68:1, February 2000. Copyright © 2000 by Blackwell Publishers, 350 Main Street, Malden, MA 02148, USA, and 108 Cowley Road, Oxford, OX4 1JF, UK. This research was supported in part by research grants from the National Institute on Aging (#AG08825, Howard S. Friedman, Principal Investigator; #AG15188-01A1, Leslie R. Martin, Principal Investigator) and by a Dissertation Grant to Leslie R. Martin from the University of California, Riverside. We would like to thank Daniel J. Ozer, M. Robin DiMatteo, Keith F. Widaman, Steven P. Reise, editor Rick Hoyle, and three anonymous reviewers for helpful comments during various stages of this project. Correspondence regarding this article may be addressed by mail to Leslie R. Martin, Department of Psychology, La Sierra University, Riverside, CA 92515; or electronically to Lmartin@lasierra.edu