Objective: To compare baseline scores of middle and high school students on the Sport Concussion Assessment Tool 2 (SCAT2) by sex and age.
Design: Cross-sectional study.
Setting: Single private school athletic program.
Participants: Three hundred sixty-one middle and high school student-athletes.
Intervention: Preseason SCAT2 was administered to student-athletes before athletic participation.
Main outcome measures: Total SCAT2 score, symptoms, symptom severity, Glasgow coma scale, modified Balance Error Scoring System (BESS), coordination, and Standardized Assessment of Concussion (SAC) with subsections: Orientation, Immediate Memory, Concentration, and Delayed Recall.
Results: No differences were found in total SCAT2 scores between sex (P = 0.463) or age (P = 0.21). Differences were found in subcomponents of the SCAT2. Twelve year olds had significantly lower concentration scores (3.3 ± 1.2) than 15 and 18 year olds (3.9 ± 1.0 and 4.2 ± 1.0, respectively). The 12 year olds also had the lowest percentage of correct responses for the SAC's concentration 5-digit (46%), 6-digit (21%), and months' backward (67%) tasks. Females presented with more symptoms (20.0 ± 2.2 vs. 20.6 ± 2.1 P = 0.007) better immediate memory (14.6 ± 0.9 vs. 14.3 ± 1.0, P = 0.022) and better BESS scores (27.2 ± 2.3 vs. 26.6 ± 2.6, P = 0.043) than their male counterparts.
Conclusions: Normative values for total SCAT2 and subscale scores show differences in concentration between ages, whereas symptoms, BESS, and immediate memory differed between sexes. We also found that 12 year olds have increased difficultly with the advanced concentration tasks, which lends support to the development of a separate instrument, such as the Child-SCAT3. The presence of developmental differences in the younger age groups suggests the need for annual baseline testing.
Clinical relevance: Subtle differences between age and sex have been identified in many components of the SCAT2 assessment. These differences may support the current evolution of concussion assessment tools to provide the most appropriate test. Baseline testing should be used when available, and clinicians should be aware of potential differences when using normalized values.