Measuring the Acute Effects of Concussion on the Sway Medical System Sports+ Test Battery.

OBJECTIVE: To document the acute effects of sports-related concussion in student athletes on tests of balance and cognitive functioning, as measured by the Sway Medical System Sports+ test battery, compared with their baseline preinjury test scores. DESIGN: Retrospective observational study. SETTING: High schools, colleges, and community healthcare settings. PARTICIPANTS: A sample of 665 young adult student-athletes, between the ages of 18 and 24 years, who completed preseason baseline assessments using the Sway Medical System Sports+ test battery, who had been documented as having sustained a "clinically diagnosed concussion," and were assessed within 3 days of sustaining a concussion. INDEPENDENT VARIABLE: Concussion sustained within one year of baseline preseason testing. MAIN OUTCOME MEASURES: Tests of Balance, Reaction Time, Impulse Control, Inspection Time, and Memory. RESULTS: Repeated-measures ANOVAs revealed significantly worse scores following a concussion compared with baseline, with all P-values <0.001. Effect sizes were medium for the Balance and Reaction Time modules, small for the Impulse Control and Inspection Time modules, and very small for the Memory module. The cognitive test most sensitive to the acute effects of concussion was Reaction Time. CONCLUSIONS: Future research will refine the clinical methodology for using the Sway tests, particularly how best to use base rates of low normative test scores in combination with personal preseason and postinjury test score comparisons.