Establishing Baseline Normative Values for the Child Sport Concussion Assessment Tool.

Importance: The Child Sport Concussion Assessment Tool (SCAT3) is a postconcussion sideline assessment tool measuring symptoms, cognition, and balance in preadolescent children. Minimal normative baseline data exist to aid decision making in clinical and athletic settings.

Objective: To collect normative baseline data for the Child SCAT3 in a large cohort of young athletes.

Design, Setting, and Participants: A cross-sectional study was conducted from May 31 to August 12, 2014, at various sporting events (basketball, soccer, baseball, and swimming) in Central Wisconsin among children 5 to 13 years of age who were English-speaking and did not report a lower leg injury within the past 2 months or a concussion within the past month. Data were analyzed between October 8, 2014, and September 12, 2016.

Main Outcomes and Measures: All Child SCAT3 components were assessed: child and parent report of symptom number and severity, cognition (Standardized Assessment of Concussion-child version [SAC-C]), and balance (modified Balance Error Scoring System [mBESS] and tandem gait). Summary statistics, mean differences, and effect sizes were calculated for each test component.

Results: Participants included 478 children (234 girls and 241 boys; mean [SD] age, 9.9 [1.9] years]) and their parents. Age had the largest effect on all Child SCAT3 components, with children 5 to 7 years of age reporting higher mean (SD) symptom severity scores compared with those 11 to 13 years of age (18.2 [10.0] vs 11.3 [9.0]; mean difference, 6.86 [95% CI, 4.22-9.50]; effect size, 0.74) and performing more poorly on the total SAC-C (mean [SD] score, 19.5 [5.1] vs 26.1 [2.1]; mean difference, -6.59 [95% CI, -7.49 to -5.68]; effect size, -2.1), mBESS (mean [SD] score, 1.67 [1.8] vs 0.76 [1.2]; mean difference, 0.91 [95% CI, 0.53-1.29]; effect size, 0.68), and tandem gait (mean [SD] time, 22.2 [8.3] vs 14.0 [3.7] seconds; mean difference, 8.23 seconds [95% CI, 6.63-9.82]; effect size, 1.55). Sex had a small effect on the mean (SD) number and severity of symptoms reported by the child (severity: boys, 15.1 [9.8] vs girls, 11.8 [9.2]; mean difference, 3.31 [95% CI, 1.60-5.02]; effect size, 0.35), mean (SD) number and severity of symptoms reported by the parent (severity: boys, 11.1 [7.7] vs girls, 9.4 [8.1]; mean difference, 1.63 [95% CI, 0.21-3.05]; effect size, 0.21), mean (SD) total SAC-C score (boys, 23.9 [3.9] vs girls, 24.9 [3.5]; mean difference, -0.92 [95% CI, -1.61 to -0.23]; effect size, -0.25), and mean (SD) mBESS score (boys, 1.21 [1.5] vs girls, 0.71 [1.0]; mean difference, 0.50 [95% CI, 0.27-0.74]; effect size, 0.38).

Conclusions and Relevance: Child SCAT3 baseline normative symptom, cognitive, and balance scores were different, with a large main effect for age and a small effect for sex. These findings may assist health care professionals with interpretation of Child SCAT3 scores for young athletes with a concussion in athletic and clinical settings.