Mullineaux, P. Y., Sperry, D., & DiLalla, L. F. (2002). The impact of parental rating bias on heritability estimates. Poster presented to the Behavior Genetics Association, July, Keystone, CO.

ABSTRACT

The purpose of this study was to determine if parent personality influenced ratings of children's behaviors. 77 siblings pairs (MZ twins, DZ twins, and different aged sibling pairs) were tested in a lab peer play situation, and mothers rated their children and themselves on aggression and inhibition scales. Structural equations modeling showed that lab and parent aggression ratings were not influenced by rater bias. MZ twins were significantly more similar than DZ twins and siblings on the aggression measures but not on the inhibition measures. The lack of similar results for inhibition may be due to the small sample size in this study. Mother ratings were significantly higher for aggression than were lab ratings. Mothers who scored in the top 25% on aggression marginally over-rated their children on aggression, although this did not hold for Inhibition. Results suggest that parent ratings of their child's aggression on the CBCL are not biased by parent personality.