The present study used meta-analytic techniques (number of samples
92) to determine the patterns of mean-level change in personality
traits across the life course. Results showed that people increase
in measures of social dominance (a facet of extraversion),
conscientiousness, and emotional stability, especially in young
adulthood (age 20 to 40). In contrast, people increase on measures
of social vitality (a 2nd facet of extraversion) and openness in
adolescence but then decrease in both of these domains in old age.
Agreeableness changed only in old age. Of the 6 trait categories, 4
demonstrated significant change in middle and old age. Gender and
attrition had minimal effects on change, whereas longer studies and
studies based on younger cohorts showed greater change.
reviewed the reference list from an earlier meta-analysis of
rank-order consistency for longitudinal studies ; reviewed
additional databases on personality development ; searched the
PsychLIT and Dissertation Abstracts databases ; reviewed current
issues of relevant journals ; reviewed the references cited in each
article for additional studies ; asked knowledgeable colleagues to
review the list
personality traits show a clear pattern of normative change across
the life course ; people become more socially dominant,
conscientious, and emotionally stable mostly in young adulthood ;
personality traits changed more often in young adulthood than any
other period of the life course, including adolescence ; no gender
differences in estimates of standardized mean change in the domains
of conscientiousness, emotional stability, openness to experience,
social dominance and agreeableness ; no relationship between cohort
and either social vitality or emotional stability ; unexpected
cohort effects for agreeableness and conscientiousness ; attrition
had no discernable effect on estimates of mean-level change over
time
a disproportionate number of longitudinal studies of personality
have been based on highly educated, middleclass or affluent samples
; the necessity of categorizing various personality measures into
the Big Five domains ; the generalizability of the findings (no
Africa, Asia)
the patterns of personality trait change are intrinsically positive
; people tend to become more socially dominant, conscientious, and
emotionally stable through midlife ; the period of young adulthood
rather than adolescence is the primary period of mean-level
personality trait development ; continued plasticity of personality
traits beyond age 30 and well into old age (social vitality,
agreeableness, conscientiousness, and openness to experience) ;
personality trait development is not just a phenomenon of childhood
but also of all adulthood
