Statistics in Football - Examining the Impact of Injuries
Modern football coverage is rife with match statistics and player performance ratings with much stock placed on possession stats and passing accuracy. Ultimately, only one statistic matters on match day: goals scored. This clearly translates to the most important stat of all, league position. The more goals you score and the fewer you let in, the higher up the league you will find yourself. Obvious, right?! So why the obsession with possession and passing accuracy?!Leicester City are at the lower end for both with an average possession of 46% (rank 19th) and a passing accuracy of 71%, the lowest in the Premier League; yet they sit at the top of the table, 5 points clear of Spurs in second and joint top in the league scoring charts with Manchester City (at time of writing). Obviously there is much missing from this type of data pertaining to style of play and tactical set up with a counter attacking side like Leicester faring poorly in the aforementioned statistics making their use seem superfluous. Additionally, statistics such as chance conversion rates for a striker might point towards the finishing ability of an individual player but, again, ultimately the only important stat is the number of goals scored. Of course, these types of statistics can be used to support an argument but the reliance on them to provide insight on their own and to drive agenda and narrative is becoming increasingly prevalent within the mainstream press. The problem with the use of statistics in this way is that it is completely devoid of any scientific principle. Is there really a tangible difference between 2.4 shots per game and 2.1 shots per game for example? Rigorous statistical tests are applied in scientific research in order to ascertain whether there truly is a difference when comparing data sets. But in football we seem to simply take the face value numbers and run with interpretations to suit our narrative.So…in this increasingly data driven world is there a role for statistics to have a greater influence in football management? I’m talking about real data collection, vigorously assessing a theory driven by specific scientific research principles implemented by PhD level researchers. The answer is, of course, yes! And given that I’m a medic you’ve probably guessed that injuries and their effects on individual players and team performance is likely to be one of the best uses of data within football. One such study followed 24 football teams from 9 countries over an 11 year period, analysing injuries and their effect on outcomes and results. Unsurprisingly, they found that the more injuries a squad suffers the less successful they tend to be in terms of final league position and/or progress in European competition (as measured by UEFA Season Club Coefficient). Interestingly this study found that the injury burden had a universal effect regardless of who was injured; first team regulars, squad players, backups or youth players on the fringes of the squad. This makes for interesting reading as the focus has traditionally been on the 14-15 players that are likely to be considered first team regulars when in fact the entire 23 man (and more) squad needs to be managed and treated in the same way. An injury to a 3rd choice centre back is potentially not seen as a major burden as the first choice pair is available to play. However, there is less opportunity to rest these players and the cumulative match burden leads to fatigue, further risk of injury and lower performance levels. This type of insight can alter the way in which coaches manage their squads and ultimately can have a positive effect on performance. The biggest change being the development of injury prevention strategies as opposed to purely focusing on treatment strategies. Clubs now heavily invest in sports science and medical teams to help ensure that players are receiving the best possible advice. This, of course is the theory, but injuries will always be part of the game. The use of proper science and evidence based medicine can help to alleviate the effect they have on team performance. In this series of articles I will look at injuries, sports science and the role of medicine in football. We’ll also look at some of the worst injuries seen in football as well as some of the most bizarre! All with a scientific and medical hat on.