The genetic basis of problem behavior in 5-year-old dutch twin pairs.
Different instruments can be used in the assessment of psychopathology in young children. In the present study the psychometric properties of a subset of items of the Devereux Child Behavior (DCB) rating scale were evaluated and the contribution of genetic and environmental influences to the variance of derived problem behavior scales was estimated. Maternal and paternal ratings were obtained in about 7600 5-year-old Dutch twin pairs. Six problem scales were derived from exploratory and confirmatory factor analysis and designated as emotional lability, aggressive behavior, attention problems, anxiety problems, physical coordination problems, and dependency. Univariate genetic analyses of the problem scales yielded large additive genetic effects. Heritability estimates ranged from 40% for aggressive behavior to 81% for attention problems. Shared environmental influences were found for aggressive behavior, anxiety problems, dependency, and emotional lability. Rater contrast and/or sibling interaction effects were found for attention problems and physical coordination.