Head injury assessment in rugby union: clinical judgement guidelines.

Background/aim: Clinical judgement is a recognised component of a complete off-field concussion assessment. This study identifies guidance criteria for team medical staff when using clinical judgement in their decision-making process during the World Rugby off-field concussion-assessment screen (HIA1).

Methods: Retrospective study of examining doctor clinical judgement in 1149 HIA1 assessments after a meaningful head impact event completed on rugby union players participating in elite-level international and national competitions between September 2015 and June 2018. We assessed (1) an abnormal subtest result as worse performance compared with preseason baseline values; (2) the proportion of cases where clinicians overruled abnormal HIA1 assessment subtest results and (3) made recommendations on how clinical judgement decisions may be made more safely based on the accuracy of clinical judgement decisions assessed against the final concussion diagnosis.

Results: One or more subtests were abnormal compared with baseline values in 857 of 1149 HIA1 assessments. Clinical judgement was used to return players to the game despite abnormal subtest results on 424 out of 857 occasions (49%). In a significant majority of cases 356/424 (84%), clinical judgement decisions were correct, with players later cleared of a concussion. An application of guided clinical judgement potentially decreased false negative assessments by 33% (21/63).

Conclusions: Clinical judgement should be applied in the diagnosis of concussion but done so cautiously. We propose doctors should only use clinical judgement to overrule either one of; or a combination of (1) an abnormal tandem gait and (2) one abnormal cognitive test.