COMMENT & ANALYSIS: St Vincent’s University Hospital in Dublin are treating us to more of the same weak research on the relationship between helmet wearing and head injury… and then dressing it up as the solution to injury reduction.
Prevention of injuries is just as important as treatment. Research like this informs how we do both. https://t.co/OHQ9ODn7sT
— SVUH Trauma Service (@SVUHTrauma) June 8, 2019
The Irish Examiner quoted Dr John Cronin, a consultant at St Vincent’s, as stating: “We found that those who did not have a helmet had a significantly higher incidence of head injury.”
Dr Cronin was challenged on Twitter by a few people, but the best question came from @clicky_here, who said: “Are raw data from this research available? Correlation is one thing, but drawing conclusions is questionable – not least since we know that cycle helmets are not designed or tested to withstand road traffic collisions involving motor vehicles. What were the circumstances in each case?”
Dr Cronin replied: “Yes this is just an association with retrospective data and that was highlighted at the presentation. Cannot prove causation. In depth details on all the circumstances of the accidents not available. Unfortunately the tweets don’t draw out all the new nuances.”
Following up, @clicky_here said: “Thank you, John, for your considered reply. In light of that would you have any comment about this article in the Examiner – it doesn’t seem to capture the nuance you’ve mentioned here.”
No reply yet from Dr Cronin. What seem to be the print version of the article has an even wider claim in its headline: “Helmets cut cyclist head injuries by half” — which is clearly unsupported nonsense.
The Irish Times also covered it. “Twelve of the cyclists died, all of whom had head injuries, according to Dr John Cronin, emergency medicine consultant at St Vincent’s University Hospital in Dublin,” the Irish Times reported. Adding: “Wearing a helmet was associated with a significantly reduced rate of head injury, he said.”
The reporting of “Twelve of the cyclists died, all of whom had head injuries” by The Irish Times is even stranger when confronted by the Examiner’s line that: “There were 12 fatalities. Of those admitted to intensive care, five were wearing a helmet.”
This type of reporting in any case is worrying — most fatal collisions in recent years (looking at all collisions, not just those who made it to hospital and were counted in the above mentioned research) seem to be at speeds where helmets would not protect people. Out of context
This isn’t just the word of cycling advocates and a cycling-focused journalist. As many readers will know, the website’s favorite article on helmets was published in the British Medical Journal and penned by Ben Goldacre, Wellcome, research fellow in epidemiology and author of Bad Science, and David Spiegelhalter, Winton professor for the public understanding of risk.
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Their article is worth reading but the key bit in relation to what Dr Cronin has made public is:
“These [pro-helmet] studies, however, are vulnerable to many methodological shortcomings. If the controls are cyclists presenting with other injuries in the emergency department, then analyses are conditional on having an accident and therefore assume that wearing a helmet does not change the overall accident risk. There are also confounding variables that are generally unmeasured and perhaps even unmeasurable. People who choose to wear bicycle helmets will probably be different from those who ride without a helmet: they may be more cautious, for example, and so less likely to have a serious head injury, regardless of their helmets.”
The Irish researchers are also dealing with mixing all types of cycling, including off-road cycling and road racing with commuting on an upright bicycle — this is like mixing motorsports with driving to the shop.
The large “unspecified” interactions is also a worry — reported hints at claiming most or all of these are cyclists falling off their bicycles without detailed further research makes it worse.
@croninjj from @svuh talking about major cycling trauma in Ireland. Huge increase in recent years. Data from @noca_irl Major Trauma Audit being used for research #MaterTrauma2019 pic.twitter.com/FArYvcG9Nm
— Louise (@louisebrent28) June 7, 2019
Meanwhile, 1,000km away from Ireland, the Dutch have build cycling into their daily routine. Their roads and streets used to looks like ours. The health benefits are clear, all age groups do it because it’s safe and attractive and 0-1% helmet wearing rate. We can do the same by following CyclingForAll.ie and related measures.
In fairness to Dr Cronin he is quoted by The Irish Times as saying: “Examining the injury characteristics suggests preventative strategies such as improved cycling infrastructure may be required.” But as our headline states: Medics focusing on helmets is a distraction to injury prevention and population health. The cycling infrastructure mention was all but lost among the coverage and the debate online.
There’s always somebody who pipes up and says something like “but sure people can go do something safer like go for a run or join a gym” — however, the health experts dealing with inactivity are clear: Building activity into people’s daily routine is far better, wider ranging, and more sustainable (in the longer-lasting sense). There’s also feedback loops too — reduction in car space and use also has the benefit of imp
Then there’s another one saying it’ll take too long to change our built environment — there’s no time like the present to start and it would happen faster if more people got behind it (for example, asking politicians to sign up to CyclingForAll.ie or asking their employers to sign up to CyclingWorks Dublin or Cork) rather than continuing with distractions.