TRAIT, SOURCE, AND ERROR VARIANCE IN THE ADHD SYMPTOMS: A MULTITRAIT- MULTISOURCE ANALYSIS WITH AUSTRALIAN AND BRAZILIAN CHILDREN
 
Gomez, R., University of Ballarat, Australia, Burns, G.L. and De Moura, M.A., Washington state University, USA and Walsh, J.A., University of Montana, USA
 
Confirmatory factor analysis (CFA) was used to model a multitrait- multisource design to evaluate the construct validity of the ADHD symptoms (e.g., the amount of trait, source, and error variance in each symptom). The two trait factors were the ADHD-inattention (IN) and hyperactivity/impulsivity (H/I) dimensions. The two source factors were parents and teachers. In study 1, parents and teachers rated 1475 Australian elementary school children on the ADHD symptoms. In study 2, parents and teachers rated 285 Brazilian elementary school children on the ADHD symptoms. Similar results occurred in both studies with most of the ADHD symptoms containing more source than trait variance, thus providing weak evidence for the construct validity of the symptoms. The study outlines the implications of such strong source effects in ADHD rating scales for the determination of relation of ADHD to other constructs. A possible solution is also offered for this problem.