Article

Separate and overlapping relationships of inattention and hyperactivity/impulsivity in children and adolescents with attention-deficit/hyperactivity disorder.

Department of Psychiatry, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd., Dallas, TX, 75390-8589, USA.
ADHD Attention Deficit and Hyperactivity Disorders 09/2012; 5(1). DOI: 10.1007/s12402-012-0091-5
Source: PubMed

ABSTRACT There is debate regarding the dimensional versus categorical nature of attention-deficit/hyperactivity disorder (ADHD). This study utilized confirmatory factor analysis to examine this issue. ADHD symptoms rated on interviews and rating scales from a large sample of individuals (ages 3-17, 74 % male, 75 % Caucasian) with ADHD were examined (n = 242). Four potential factor structures were tested to replicate prior findings in a sample with a wide age range and included only participants who met DSM-IV-TR diagnostic criteria for ADHD. Correlations with executive function measures were performed to further assess the separability and validity of the derived factors. The data support a bifactor model with a general ADHD factor and two specific factors, inattention and hyperactivity/impulsivity. Importantly, the individual factors were also differentially correlated with executive functioning measures. This study adds to a growing literature suggesting both a general component to ADHD, as well as dimensional traits of inattention and hyperactivity/impulsivity, associated with distinct executive functioning profiles. The presence of a general underlying factor contraindicates separating the inattentive and combined subtypes of ADHD into distinct disorders.

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