16.4 Evaluation of a Single Parent–Reported Item Indicator of ADHD Severity

Abstract

The aim of this study was to evaluate a parent-reported single item indicator of ADHD severity against reported ADHD symptoms, impairment, and presence of co-occurring conditions in a nationally drawn sample of children aged 4 to 17 years with current ADHD (n = 2495). This study used data from the National Survey of the Diagnosis and Treatment of ADHD and Tourette Syndrome. Respondent parents answered a single question about their children’s ADHD severity (mild, moderate, severe) as well as symptom (k = 18) and impairment (k = 8) questions from the Vanderbilt ADHD Diagnostic Parent Rating Scale and questions about whether their child has any of the 12 current co-occurring mental, behavioral, or developmental disorders (MBDDs). Analyses including calculation of weighted means, prevalence, and prevalence ratios (PRs), and ANOVA statistical testing were conducted in SAS-callable SUDAAN v11.0.3 to account for the complex design and sampling weights. The proportion of children with each reported inattentive, hyperactive, or impulsive symptom was higher for children with moderate ADHD (PR range: 1.30-2.02) and severe ADHD (PR range: 1.42-3.92) compared to children with mild ADHD. The mean total ADHD symptom count by severity was 6.5 for mild ADHD, 10.1 for moderate ADHD, and 13.1 for severe ADHD (p < 0.0001). A similar pattern was found for the prevalence of domains with reported impairment, with children with mild ADHD having a mean of 2.3 domains with impairment, 3.2 domains of impairment for children with moderate ADHD, and 4.1 domains of impairment for children with severe ADHD (p < 0.0001). There was also a significant association between ADHD severity and prevalence of each co-occurring MBDD, with each MBDD having a higher prevalence in children with severe ADHD than those with mild ADHD (PR range: 1.47-8.89). In a nationally drawn sample of children with current ADHD, children with more severe ADHD according to a single parent-reported item had more ADHD symptoms, experienced more domains of impairment, and were more likely to have co-occurring MBDDs than children with reported mild ADHD. These results provide evidence for the validity of the single item on ADHD severity, allowing for efficient measurement of disorder severity in national surveys and other types of data collection.