Conscientiousness
Development

Currently, little is known about conscientiousness in young children because the self-report inventories typically used to assess it are not appropriate for that age group. There are likely individual differences in this factor at an early age. It is known, for example, that some children have attention deficit/hyperactivity disorder, which is characterized in part by problems with concentration, organization, and persistence. Longitudinal and cross-sectional studies suggest that conscientiousness is relatively low among adolescents but increases between 18 and 30 years of age. Conscientiousness generally increases with age from 21 to 60, though the rate of increase is slow.

Individual differences are strongly preserved, meaning that a careful, neat, and scrupulous 30-year-old is likely to become a careful, neat, and scrupulous 80-year-old.
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