Date of Award
Master of Science (MS)
Hoelzle, James B.
There are many challenges associated with assessment and diagnosis of ADHD in adulthood. A significant percentage of adult patients may fabricate or exaggerate ADHD symptoms when completing self-report measures in hopes of securing a diagnosis. Further, there are conflicting findings surrounding the similarity between ADHD presentation in adults and children, reflected in rating-scales and symptoms outlined in the diagnostic criteria. This research provides novel information regarding relationships between common adult ADHD self-report form items and corresponding theoretical constructs of inattention (IA) and hyperactivity/impulsivity (H/I). Utilizing the graded response model (GRM) from item response theory (IRT), a comprehensive item-level analysis of adult ADHD rating scales in a clinical population was conducted with Barkley’s Adult ADHD Rating Scale-IV, Self-Report of Current Symptoms (CSS), a self-report diagnostic checklist. A similar self-report measure quantifying retrospective report of childhood symptoms, Barkley’s Adult ADHD Rating Scale-IV, Self-Report of Childhood Symptoms (BAARS-C), was also evaluated to further understand ADHD item functioning through the lifespan. Differences in item functioning were also considered after identifying and excluding individuals with suspect effort. Results reveal that items associated with symptoms of IA and H/I are endorsed differently across the lifespan, and these data suggest that they vary in their relationship to the theoretical constructs of IA and H/I. Screening for sufficient effort did not meaningfully change item level functioning. The application IRT to direct item-to-symptom measures allows for a unique psychometric assessment of how the current DSM-5 symptoms represent latent traits of inattention and hyperactivity/impulsivity. Meeting a symptom threshold of five or more symptoms may be misleading. Closer attention given to specific symptoms in the context of the clinical interview and reported difficulties across domains may lead to more informed diagnosis.
Available for download on Wednesday, November 25, 2020