Does Perception Match Reality? Clinical Performance of the Percent of Normal Rating for Sport-Related Concussion.

CONTEXT: The percent of normal (PoN) rating is included in the Sport Concussion Office Assessment Tool 6 (SCOAT6) and used in concussion care, but clinicians lack empirical guidance on how to interpret this value.

OBJECTIVE

To evaluate the ability of the PoN rating to discriminate athletes with sport-related concussion (SRC) from healthy controls and measure perceived recovery.

DESIGN

Prospective cohort study.

SETTING

Specialty clinic and research registry.

PATIENTS OR OTHER

PARTICIPANTS

Athletes within 3 to 30 days of SRC and healthy controls aged 13 to 29 years.

INTERVENTIONS: Participants completed a comprehensive clinical evaluation at their initial (V1) and follow-up (V2) visit approximately 14 days later. Percent of normal is a single item self-report using a 0% to 100% scale embedded in the SCOAT6 symptom evaluation. Univariate linear regressions examined the association between clinical outcomes at V1/V2 and PoN at V1/V2 for the SRC cohort. Receiver operating characteristic curve analyses with area under the curve examined PoN to discriminate those with SRC from controls at V1 and to discriminate recovery status at V2.

MAIN OUTCOME MEASURES: Percent of normal ratings, symptom- and performance-based concussion measures, clinical recovery status.

RESULTS

Percent of normal demonstrated outstanding clinical performance discriminating SRC (area under the curve = 0.95), with an optimal cutoff of <87% PoN (sensitivity = 0.86, specificity = 0.91). Percent of normal ratings at both visits were associated with most symptom- and performance-based measures (P < .001). A PoN rating of >95% at V2 yielded the most balanced cut point for classifying clearance (sensitivity = 0.70, specificity = 0.74).

CONCLUSIONS

Percent of normal demonstrated strong clinical performance in discriminating those with SRC from controls and moderate congruence with clinical recovery across a multidomain assessment. Percent of normal was also associated with multiple symptom- and performance-based measures across recovery. The PoN provides clinicians with a brief and intuitive adjunctive tool to monitor recovery in athletes after this injury.