Why we should focus on the burden of injuries and illnesses, not just their incidence

More and more sports medicine clinicians are taking an active approach to prevent injury and illness within their team.1–3 The first steps in developing a risk management plan is risk estimation and assessment.4–7 In this phase, the main questions are: what injuries can we expect? Or illnesses? And which are the most serious? Another question is: when is injury risk the greatest? The purpose is to identify which problems need to be focused on in a risk management plan in order to mitigate risk. These questions can be answered by establishing continuous injury surveillance within the team or by reviewing data from epidemiological studies on teams from a similar level.6 7 However, as a practitioner, you need to know how to interpret such data, whether they are your own or from others. A number of consensus statements have been published to encourage consistency in how injuries are defined and reported in epidemiological studies, initially on cricket (2005, updated in 2016),8 9 followed by football (2006)10 and several other sports such as rugby (2007),11 tennis (2009),12 athletics (2014)13 and aquatic sports (2016).14 In general, these recommend that the rate of injury should be reported as injury incidence, calculated as number of injuries per 1000 hours of exposure. This recommendation has since been followed by the vast majority of surveillance studies, and incidence is typically also the main outcome used to compare sports, genders, age groups and so on. However, we argue that focusing on injury/illness incidence alone may give an incomplete and even erroneous picture of risk. It should be noted that the consensus statements also recommend that injury severity be reported, generally as the number of days from the date of injury to the date of the player’s return to full participation. …