Assessment of children must deal with limited agreement among sources of data. For example, correlations between reports by mothers, fathers, teachers, and other informants are typically modest to moderate. The differences between informants’ reports may reflect such factors as differences in the behavior they observe or differences in their judgment of the same behavior. Differences in their judgment of the same behavior could be considered biases, in the sense that they reflect characteristics of the informant rather than of the child who is being assessed.

To test whether differences in parents’ ratings reflect actual differences in children’s behavior vs. rater biases, Jolande van der Valk, Edwin van den Oord, Frank Verhulst, and Dorret Boomsma fitted two contrasting structural equation models to mothers’ and fathers’ CBCL ratings of 3,501 pairs of Dutch 3-year-old twins. One model, called the “Rater Bias” model, assumed that each parent provides a biased assessment of the same behavior. The second model, called the “Psychometric” model, assumed that each parent assesses unique aspects of each child’s behavior, as well as common aspects.

The Psychometric model was found to fit the data significantly better than the Rater Bias model. The different contributions of mothers’ and fathers’ ratings uniquely identified somewhat different genetic and environmental influences on their children’s Internalizing and Externalizing problems. In other words, differences between mothers’ and fathers’ ratings can capture important differences in children’s behavior. Use of both mother and father ratings can thus increase the precision of genetic analyses as well as the precision and comprehensiveness of assessment of individual children for clinical and other purposes.

Reference: Van der Valk, J.C., van den Oord, E.J.C.G., Verhulst, F.C., & Boomsma, D.I. (2001). Using parental ratings to study the etiology of 3-year-old twins’ problem behaviors: Different views or rater bias? Journal of Child Psychology and Psychiatry, 42, 921-931.