Environmental, and Rater Effects on CBCL Attention Problems,
Aggressive Behavior, and Anxious/Depressed Syndrome Scores
Research is increasingly demonstrating genetic influences
on many aspects of human functioning. However, because genetic
factors are unlikely to account for all variations in functioning,
it is essential to analyze the interplay of genetic, environmental,
and methodological effects on specific measures of functioning.
Using CBCL ratings of 984 8- to 12-year-old twins participating
in the Missouri Twin Study, Hudziak et al. (2000) found
that genetic factors accounted for 60 to 68% of the variance
in Attention Problems; 70 to 77% of the variance in Aggressive
Behavior; and 61 to 65% of the variance in Anxious/Depressed
syndrome scores. There were thus large genetic effects on
these syndromes. However, there were also moderate environmental
effects, ranging from 23% of the variance in the Aggressive
Behavior syndrome scores for boys to 40% of the variance in
the Attention Problems syndrome scores for girls. In addition,
Hudziak et al. found negligible rater bias effects
on the CBCL syndrome scores. The lack of rater bias effects
on the CBCL contrasted with findings for interviews and questionnaires
using DSM criteria. The authors concluded that the intermingling
of items tapping different syndromes on the CBCL helped to
prevent rater biases that arise when symptoms are grouped
together according to types of disorders.
Reference: Hudziak, J.J., Rudiger, L.P., Neale,
M.C., Heath, A.C., & Todd, R.P. (2000). A twin study of
inattentive, aggressive, and anxious/depressed behaviors.
Journal of the American Academy of Child & Adolescent
Psychiatry, 39, 469-476.