shows how the four groups differed in Openness. In each culture,
Openness was highest in the youngest groups and lowest in the oldergroups. These age differences are significant in all five cultural groups.In the case of Neuroticism, there were no significant age differences inthe Italian and Croatian groups, but the German, Portuguese, and SouthKorean samples followed the American pattern. All five cultures repli -
cated American findings for Extraversion, Agreeableness, and Consci -
entiousness.
History, Culture, and Cross-Sectional Comparisons
These are, of course, cross-sectional comparisons, and (as we discussed
in the last chapter), there are good reasons to be cautious in inferringmaturational changes from cross-sectional age differences. In particular,there is always the possibility that differences are cohort effects. Theolder respondents in Figure 4 may always have been lower in Extra-version and higher in Conscientiousness because they were born in anearlier era when these traits were shaped. Ordinarily , this argumentcannot be challenged except by longitudinal data, and it will be yearsbefore extensive longitudinal data from other cultures are available.
But cross-cultural research is not ordinary research. Within any one
culture, age and birth cohort are hopelessly confounded, but this neednot be the case when data from two or more cultures are compared. AsRiley , Johnson, and Foner (1972) pointed out long ago, in interpretingcohort effects, “our concern is not with dates themselves, but with theparticular sociocultural and environmental events, conditions, andchanges to which the individual is exposed at particular periods” (pp.419–420). People growing up in South Korea were exposed to very dif -
ferent events, conditions, and changes than people growing up in the
United States or Portugal (see Table 10 for a synopsis of history in thesefive cultures), so one might expect a very different pattern of cohort ef -
fects. If life history shapes personality traits, and if histories differ, then
cross-sectional age comparisons should also differ.
But as Figure 4 shows, that is not the case. The same general trends
are found in each of these five cultures. Later studies showed that thepattern continues in Russia, Estonia, Japan, the Czech Republic, GreatBritain, Spain, T urkey , and China (Costa, McCrae, et al., 2000; McCraeet al., 2000; Yang, McCrae, & Costa, 1998). Consider how different lifeexperience has been for people growing up in these countries. After92 PERSONALITY IN ADULTHOOD