Diagnostic accuracy and reliability of sideline concussion evaluation: a prospective, case-controlled study in college athletes comparing newer tools and established tests

ObjectiveTo assess diagnostic accuracy and reliability of sideline concussion tests in college athletes.MethodsAthletes completed baseline concussion tests including Post-Concussion Symptom Scale, Standardised Assessment of Concussion (SAC), modified Balance Error Scoring System (m-BESS), King-Devick test and EYE-SYNC Smooth Pursuits. Testing was repeated in athletes diagnosed acutely with concussion and compared to a matched teammate without concussion.ResultsData were collected on 41 concussed athletes and 41 matched controls. Test–retest reliability for symptom score and symptom severity assessed using control athletes was 0.09 (−0.70 to 0.88) and 0.08 (−1.00 to 1.00) (unweighted kappa). Intraclass correlations were SAC 0.33 (−0.02 to 0.61), m-BESS 0.33 (−0.2 to 0.60), EYE-SYNC Smooth Pursuit tangential variability 0.70 (0.50 to 0.83), radial variability 0.47 (0.19 to 0.69) and King-Devick test 0.71 (0.49 to 0.84). The maximum identified sensitivity/specificity of each test for predicting clinical concussion diagnosis was: symptom score 81%/94% (3-point increase), symptom severity score 91%/81% (3-point increase), SAC 44%/72% (2-point decline), m-BESS 40%/92% (5-point increase), King-Devick 85%/76% (any increase in time) and EYE-SYNC Smooth Pursuit tangential variability 48%/58% and radial variability 52%/61% (any increase). Adjusted area under the curve was: symptom score 0.95 (0.89, 0.99), symptom severity 0.95 (95% CI 0.88 to 0.99), SAC 0.66 (95% CI 0.54 to 0.79), m-BESS 0.71 (0.60, 0.83), King-Devick 0.78 (0.69, 0.87), radial variability 0.47 (0.34, 0.59), tangential variability 0.41 (0.30, 0.54)ConclusionTest–retest reliability of most sideline concussion tests was poor in uninjured athletes, raising concern about the accuracy of these tests to detect new concussion. Symptom score/severity had the greatest sensitivity and specificity, and of the objective tests, the King-Devick test performed best.