ADHD Subtypes and the Convergent Validity of the Brief Three-Factor Approach and D-KEFS Color-Word Interference Test
Deficits in executive functioning (EF) often translate to significant impairment in real-life situations. EF can be assessed by performance-based tests or through the use of behavior ratings; however, most research has found little to no associations between performance-based EF tests and parent ratings. ADHD is a neurodevelopmental disorder characterized by EF deficits, but some studies have found differences on EF measures between subtypes of ADHD. The first aim of this study is to examine the convergent validity between the D-KEFS CWIT, a performance-based EF task, and the recently revised three-factor BRIEF. The second aim of this study is to examine whether there are differences between ADHD-I and ADHD-HI/C subtypes on either of these EF measures. A sample of 49 children with ADHD, aged 6 to 12 years, were administered the D-KEFS CWIT and their parents were given the BRIEF to complete. No significant correlations between Condition 3 of the CWIT and the new Self-Monitor and Inhibit subdomains of the BRIEF were obtained, but the Shift subdomain of the BRIEF significantly correlated with Condition 3. Participants with ADHD-HI/C were rated by parents as having greater executive dysfunction compared to participants with ADHD-I. No significant differences between subtypes were observed on the CWIT after controlling for symptoms of inattention. It would be beneficial to continue developing EF measures with the goal of greater convergent validity between performance-based and informant-report measures. Also, more research should be conducted in identifying differences between ADHD subtypes in their EF profiles as it can potentially aid in improving evaluation and treatment of this disorder.