The Postconcussion Symptom Scale: Utility of a Three-Factor Structure

Purpose: This study aimed to determine the factor structure of a 19-item Postconcussion Symptom Scale and to examine associations between factor scores and sex, previous history of concussion, and length of time since injury. Methods: This is a retrospective medical record review of pediatric patients with concussion seen in a sports medicine clinic from April 2008 to September 2012. We performed an exploratory factor analysis (EFA) followed by a confirmatory factor analysis (CFA). ANOVA and regression analysis were used to examine associations between factor scores and sex, previous history of concussion, mood disorder, anxiety disorder or attention-deficit disorder, and length of time since injury. Results: EFA supported a three-factor solution for postconcussive symptoms employing 18 of the original 19 scale items. Factor 1 consisted of eight cognition-related items, factor 2 consisted of six somatic-related items, and factor 3 consisted of four emotional-related items. CFA results confirmed the unidimensionality of factors 1 (neurocognitive), 2 (somatic) and 3 (emotional), with factor 3 being considered borderline. Females and patients with anxiety disorders had significantly worse (higher) scores on all three factors. Patients seen >14 d after the concussive injury had worse (higher) factor 3 (emotional) scores than those seen <14 d after the injury. There was no significant difference in postconcussive symptom factor structures between those with and without a previous history of concussion. Conclusions: Our investigation demonstrates a consistent symptom 3-factor structure of the Postconcussion Symptom Scale in pediatric patients with concussions. Females and patients with anxiety disorders had higher scores than males for all three factors. Patients seen >14 d after concussive injury had higher scores for emotional symptoms, suggesting that prolonged concussion symptoms may affect emotional health.