A new study was reported last week about the apparent connection between ‘heading’ footballs and an increased risk of brain injury. The results of the study were published in an on-line edition of the science journal Radiology, and widely reported in the media, including in the Telegraph, who ran the story with the headline ‘Headers can damage a footballer’s brain, study finds’.
NHS Choices has responded to this by pointing out that there is more to the study than meets the eye. They say that no causal link has yet been established between headers and brain damage, and that media reports have been overly alarmist on the subject.
The study, which was conducted in New York, involved carrying out MRI brain scans on 37 amateur football players, along with other neurological tests., besides asking them to complete a questionnaire estimating the number of times they had headed the ball in the previous 12 months. The research sought to establish whether there was a possible association between lifestyle factors – such as heading footballs – and health outcomes, such as brain changes. The research reported that more frequent headings showed changes similar to those seen in people who have suffered a traumatic brain injury, as well as poorer memory scores, prompting the media coverage and concern.
In spite of these study findings though, NHS Choices has sought to reassure the public by emphasising the following limitations of the study:-
- Methodology
Research participants were only given brain images and tests at one point in time, after playing football and heading the ball had already taken place, rather than at any earlier points in their lives. This means that any damage detected could have always appeared that way in brain imaging, or at least existed for a long time prior to the headers taking place. There is no direct causal link between headers and brain damage, as there could have been other factors at play that caused it.
- Small study size
Only 37 amateur footballers took part in the study, making this a very small sample size. Larger studies would need to be carried out before more general associations could be made. Testing with professional footballers, who have better heading techniques, may also reveal other differences.
- Heading was self-reported
Participants were asked to report on how often they had headed the ball in the previous 12 months. This relies on the accuracy of their memory and reporting, potentially making the results less reliable
- No differentiation on types of headers
The research did not distinguish between different types of headers. The speed, velocity and site of impact would all have a bearing if looking to establish a repetitive relationship.
- Outcomes for players
While the research observed changes in brain function linked to the activity, there is no information available on how/ whether this affected outcomes and what it means in real terms for players affected
NHS Choices states that to reliably asses the effects of heading footballs, regular brain imaging would need to take place, with the initial assessment being conducted years before players even begin to play. This would then need to be followed-up over a period of time, along with an objective assessment of the number of headers that players have made. However, at this stage such a study is likely to be unfeasible.
Read source article here http://www.nhs.uk/news/2013/06June/Pages/No-proof-heading-footballs-causes-brain-damage.aspx
Reader article as it appeared in theTelegraphhere http://www.telegraph.co.uk/sport/football/10112281/Headers-can-damage-a-footballers-brain-study-finds.html
