The current study was designed to address this issue by analyzing a sample of kinship pairs drawn from the Child and Young Adult Supplement of the National Longitudinal Survey of Youth 1979 (CNLSY).
Analyses of these data revealed that genetic factors accounted for between 74 and 92 percent of the stability in self-control and between 78 and 89 percent of the change in self-control. Shared and nonshared environmental factors explained the rest of the stability and change in levels of self-control.
A combination of genetic and environmental influences is responsible for the stability and change in levels of self-control over time.