The hierarchical factor model of ADHD: invariant across age and national groupings?

• Published in: Journal of child psychology and psychiatry 2012-03, Vol.53 (3), p.292-303
• Main Authors: Toplak, Maggie E., Sorge, Geoff B., Flora, David B., Chen, Wai, Banaschewski, Tobias, Buitelaar, Jan, Ebstein, Richard, Eisenberg, Jacques, Franke, Barbara, Gill, Michael, Miranda, Ana, Oades, Robert D., Roeyers, Herbert, Rothenberger, Aribert, Sergeant, Joseph, Sonuga-Barke, Edmund, Steinhausen, Hans-Christoph, Thompson, Margaret, Tannock, Rosemary, Asherson, Philip, Faraone, Stephen V.
• Format: Article
• Language: English
• Subjects: ADHD; Adolescent; Adolescents; Age Differences; Age Distribution; Attention Deficit Disorder with Hyperactivity - epidemiology; Attention Deficit Disorder with Hyperactivity - psychology; Attention deficit disorders. Hyperactivity; Attention Deficit Hyperactivity Disorder; bifactor model; Biological and medical sciences; Child; Child clinical studies; Child, Preschool; Children; Children & youth; Clinical Psychology; Comparative Analysis; Data Analysis; Europe; Europe - epidemiology; Factor Analysis; Factor Analysis, Statistical; Factor Structure; factorial invariance; Faculty; Female; Foreign Countries; hierarchical models; Humans; Informants; Interview, Psychological; Interviews; Israel; Male; Medical sciences; Models, Psychological; Parents; Parents - psychology; Psychology. Psychoanalysis. Psychiatry; Psychopathology. Psychiatry; Siblings; Siblings - psychology; Symptoms
• ISSN: 0021-9630; 1469-7610
• DOI: 10.1111/j.1469-7610.2011.02500.x

Objective:  To examine the factor structure of attention‐deficit/hyperactivity disorder (ADHD) in a clinical sample of 1,373 children and adolescents with ADHD and their 1,772 unselected siblings recruited from different countries across a large age range. Hierarchical and correlated factor analytic models were compared separately in the ADHD and sibling samples, across three different instruments and across parent and teacher informants. Specific consideration was given to factorial invariance analyses across different ages and different countries in the ADHD sample. Method:  A sample of children and adolescents between 5 and 17 years of age with ADHD and their unselected siblings was assessed. Participants were recruited from seven European countries and Israel. ADHD symptom data came from a clinical interview with parents Parental Account of Childhood Symptoms and questionnaires from parents and teachers (Conners Parent and Teacher). Results:  A hierarchical general factor model with two specific factors best represented the structure of ADHD in both the ADHD and unselected sibling groups, and across informants and instruments. The model was robust and invariant with regard to age differences in the ADHD sample. The model was not strongly invariant across different national groups in the ADHD sample, likely reflecting severity differences across the different centers and not any substantial difference in the clinical presentation of ADHD. Conclusions:  The results replicate previous studies of a model with a unitary ADHD component and separable specific traits of inattention and hyperactivity/impulsivity. The unique contribution of this study was finding support for this model across a large developmental and multinational/multicultural sample and its invariance across ages.