In what is thought to be the longest-running study ever, researchers at University of Edinburgh failed to find a significant correlation between their participants’ personality scores at age 14 and their scores on the same items at the age of 77.
“Personality in older age may be quite different from personality in childhood,” they say.
The study, which is published in Psychology and Aging, examined data from a Scottish survey conducted in 1950. In this survey, teachers assessed children aged around 14 on six personality characteristics - Self-Confidence, Perseverance, Stability of Moods, Conscientiousness, Originality, and Desire to Excel. In 2012, the authors traced 635 of the original participants now aged around 77, and invited them to participate in a second study. While many declined to participate, 174 agreed and completed questionnaires and telephone interviews.
They rated themselves on the same six personality traits their teachers had rated them, and also asked a spouse, close friend or relative to rate them on these traits too. In addition, participants took some intelligence tests and their general wellbeing was measured.
Previous studies have shown personality is subject to a lifelong series of relatively small changes—particularly in adolescence and early adulthood, but continuing even into older age. “As a result of this gradual change, personality can appear relatively stable over short intervals—increasingly so throughout adulthood,” writes study author Matthew Harris and his colleagues. “However, the longer the interval between two assessments of personality, the weaker the relationship between the two tends to be.”
They say their results suggest that, when the interval is increased to as much as 63 years, there is hardly any relationship at all. “If so, personality changes only gradually throughout life, but by older age it may be quite different from personality in childhood,” they write.
The authors do recognise there are some limitations with their study, such as a small and relatively similar sample size. Also, in this study, while a third person did rate participants, they also self-rated themselves; in the original study they were rated by teachers. Either way, there is the potential for bias in the rating.
“Future studies should focus on developing better understanding of how and why personality changes throughout the life course,” they write.