OBJECTIVE: To compare Child Sport Concussion Assessment Tool Fifth Edition (Child SCAT5) performance between uninjured children with attention-deficit/hyperactivity disorder (ADHD) and precisely matched controls without ADHD. STUDY DESIGN: A nested case-control study was conducted within a cohort of middle school athletes (age 11-12 years) who completed preseason testing. Students with ADHD were individually matched to students without ADHD based on age, sex, language spoken at home, number of prior concussions, sport, and school they attended. The final sample included 54 students (27 with ADHD and 27 controls), 38 (70.4%) boys and 16 (29.6%) girls (average age: 11.7 years, SD = 0.5). RESULTS: Children with ADHD reported more symptoms (M = 13.33, SD = 5.69, P < .001) and greater symptom severity (M = 22.59, SD = 1 1.60, P < .001) compared with controls (total symptoms: M = 6.44, SD = 4.96; symptom severity: M = 8.04, SD = 6.36). Children with ADHD performed similarly to controls on the Child SCAT5 cognitive tests. Children with ADHD committed 3 times as many total balance errors (median = 6) than children without ADHD (median = 2) and committed twice as many errors on single leg stance (ADHD median = 4; No ADHD median = 2) (P values < .001). CONCLUSIONS: Children with ADHD endorsed more concussion-like symptoms and performed worse on balance testing during preseason Child SCAT5 assessment compared with matched controls without ADHD. These findings highlight the challenges of interpreting Child SCAT5 performance in children with ADHD following a concussion or suspected concussion and illustrate the value of administering the measure to children to document their pre-injury performance.
