Raftery, MartinKemp, SimonPatricios, Jonathan SperidonMakdissi, MichaelDecq, Philippe2016-07-132016-07-132016-06Raftery, M, Kemp, S, Patricios, JS, Makdissi, M & Decq, P 2016, 'It is time to give concussion an operational definition : a 3-step process to diagnose (or rule out) concussion within 48 hours of injury : World Rugby guideline ', British Journal of Sports Medicine, vol. 50, no.11, pp. 642-643, doi:10.1136/bjsports-2016-095959.0306-3674 (print)1473-0480 (online)10.1136/bjsports-2016-095959http://hdl.handle.net/2263/55687Concussion is the number one injury risk in contact and collision sports. Identification of concussive events is critical to optimise injury management and, as identified by Quarrie and Murphy¹, to undertake accurate injury surveillance studies. The Zurich Consensus Statement on Concussion² provides an expanded theoretical or conceptual definition of concussion but there is not yet an operational definition of concussion. In 2012 World Rugby introduced a new pitch side process for assessment of head injuries, called the HIA³ (Head Injury Assessment). During the evolution of this process an operational definition of concussion has been developed and successfully implemented.en© 2016 by the BMJ Publishing Group Ltd. All rights reserved.ConcussionContact and collision sportsInjury managementHead injuriesDefinitionOperationalDiagnosisPostprint Article