In contrast to the preceding outcomes, let us assume that each symptom rating contained more source than trait variance. In the traditional view, such a result would indicate that the symptom ratings contained mostly bias, thus indicating that the ADHD-IN, ADHD-HI, and ODD symptom ratings have no construct validity. The alternative view would argue that the strong source effects could indicate that each source has a valid, but different, view of the child's behavior because the child's behavior is source specific. A third possibility is that the source effects represent a mixture of bias and validity with there being a need to determine which aspect is most important.
By having two sources in each situation (mothers and fathers for the home situation and teachers and aides for the school situation), it is possible to further investigate the reason for each symptom rating containing more source than trait variance. To do this, it is necessary to perform two separate CFAs. The first analysis would use CFA to model a multitrait (ADHD-IN, ADHD-HI, and ODD) by multisource matrix where the two sources are teachers and teachers' aides. The second analysis would use CFA to model a multitrait by multi-source matrix where the two sources are mothers and fathers. If the strong source effects in the initial analysis reflect situation specific behavior, then the separate analyses for each situation should result in an increase in trait variance and a decrease in the source variance for the symptom ratings. In other words, if the teachers and aides provide similar ratings for the classroom, the mothers and fathers provide similar ratings for home, and the children's behavior is situationally specific, then the amount of trait variance should increase for each symptom rating. In contrast, if the source variance for each symptom rating was still larger than the trait variance in the separate situation analyses, then this result would favor the bias view. Additional research would then be required to determine the specific factors for the mother, father, teacher, and aide sources responsible for the bias.
Was this article helpful?