COMMENT & ANALYSIS: Since last Thursday the Irish media has suffered from a serious case of bicycle helmets and “lies, damned lies, and statistics“.
It started with a news story — “Almost 70% of cyclists without helmet at time of head trauma” — which The Irish Times deemed worthy of its front page on Thursday. This compelling headline fits right into the phrase “lies, damned lies, and statistics”.
So, it’s first worth saying that The Irish Times has a bit of a messed up relationship with reporting on cycling as transport and related issues such as BusConnects. We have highlighted this more than a few times (see our archive).
Irish Times journalists continue to insist the issues with their coverage of cycling is a myth. While it is true that the newspaper publishes regular pro-cycling articles, but these are heavily weighted towards the features section — the way cycling related news is covered leaves a lot to be desired and the comment section of the newspaper is a mixed bag. Reporting of cycling related news by the Irish Times is too often flawed,
Last week’s cover story on bicycle helmets in The Irish Times was followed by coverage on radio programmes on RTE, Newstalk and other stations, and articles in the Irish Examiner and in The Sunday Times. So, the old “newspaper of record” still packs a punch. This makes reporting such a flawed story even worse.
Proportion of cyclist with/without helmets
If you’re going to plaster a statistic on a headline over an article on a newspaper’s cover page, the stat should have some statistical significance and that should be backed up within the article.
The excuse of ‘we’re just reporting or providing the data’ does not work here as the data is clearly presented to support helmet wearing.
So, if your headline is ‘almost 70% of cyclists presenting with a head injury don’t wear helmets’, then the proportion of cyclists generally without helmets should be statistically significantly lower.
However, according to a 2016 observational study by the Road Safety Authority, the helmet wearing rate is around 38% (public and private bicycle combined). This is also close to the findings of a 2017 national self-reporting survey conduced for the Department of Transport ahead of National Bike Week which found 39% of cyclists saying they wear helmets.
The difference between 70% and around 60% is not statistical significance. It’s well within a margin for error. This is made worse again by the other factors here (see below).
There’s no published research
A number of reports and interest groups statements referred to the research as if it has been published. It has not been published even now. So, The Irish Times is publishing a front page story about bicycle helmets based on snippets of yet-to-be published research. It seems to be all from an outline of the data given verbally at a conference in Dublin.
Research will at best be a case-control study
In their BMJ article, Ben Goldacre, Wellcome, research fellow in epidemiology and author of Bad Science, and David Spiegelhalter, Winton professor for the public understanding of risk argue that case-control studies which “suggest that, for individuals, helmets confer a benefit” are “vulnerable to many methodological shortcomings”.
The two explain: “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.”
Data set too small and incomplete
According to media reports, of the 26 cyclists treated at the national neurosurgical centre at Beaumont Hospital over 30 months, 18 were not wearing helmets, 2 were and the remaining 6 were unknown.
A data set of 26 is small and when 23% of the data being used is incomplete, it makes you wonder how reliable the data set is. The sample volume seems to be too small to draw conclusions.
Sports and transport
The Irish Times reported that: “Cycling accounted for all four of the sports and exercise-related deaths recorded at the centre over the period. Two of these patients were not wearing helmets, one was and the status of the other mortality was unknown. Two of the dead cyclists are recorded as having fallen off their bicycle, while the other two were knocked off.”
Lumping mountain biking, racing cycling and an old lady cycling to the shop is about as useful as lumping motor racing with commuting by car. But medical researchers seem to have a serious issue lumping cycling and sport and cycling as transport together because their data seems to be so unreliable to start with.
Colouring the data
The Irish Times quotes lead author Dr Phil O’Halloran of Beaumont Hospital as stating: “The figures show no sport is immune to head injury, so common sense needs to prevail.”
This brings up the question: Were the researchers interested in scientific research or were they just looking for data that might back up helmet wearing?
Personally, if I’m going to rely on “common sense”, as O’Halloran asks, I think I’ll go with ~17 million people in the Netherlands when the helmet wearing rate is under 1% and they have very high levels of young and old people cycling, yet, they have the safest cycling at least in the EU.
Bias for higher numbers over more serious?
It’s unclear if this issue is of the newspaper’s or the medics or both, but there seems to be a bias for higher numbers overall being taken over more serious incidents. Deep within the story we read that that rugby “accounted for the highest rate of patient transfer, and five of these six patients required major brain surgery.”
The 2008 Phillips Report on head injures in Ireland also comes to the conclusion of promoting bicycle helmets with no support for such in the data provided. However, if we look at the data in that report, we find that people cycling mostly suffer mild brain injury when compared to pedestrians or motorists. Also compared to other road users, cyclists — including non-helmeted ones — had by far the lowest irreversible injury rate and lowest mortality rate.
Helmets cannot stop brain injuries
This is a scientific fact — bicycle helmets cannot stop brain injuries for two reasons. Firstly, concussion are basically an internal injury caused by movement of the brain within the skull and, secondly, more serious skull fractures are way above the force a flimsy bicycle helmet can take. The air-bag type of bicycle helmets seem to be more of a help with the latter but are an impractical solution given the low level of risk.
Groups like Acquired Brain Injury Ireland and medics researching the area used to nearly imply otherwise, but there seems to be a change of tactics and in the last week both researches and head injury groups have been trying to preempt arguments around the limits of helmets.
The problem with making this argument with this research is that you must then allow for it in your findings. But if we account for concussions and very high level impacts, the already limited data would be lowered in quality again.
Helmets are an understandable emotional response
The promotion of bicycle helmets is an understandable emotional response especially from people who care for head injury victims. But such makes for bad science, poor journalism, and poorer policy — misdirecting attention away from solutions needed.
I was told on Twitter by one medic that perhaps it’s easier for cycling advocates to take a population-level approach to this issue because they’re not responsible for the care of people whose brain injuries might have been less severe had they been wearing a helmet. This is an understandable response, but bad science.
As Goldacre and Spiegelhalter wrote: “Standing over all this methodological complexity is a layer of politics, culture, and psychology. Supporters of helmets often tell vivid stories about someone they knew, or heard of, who was apparently saved from severe head injury by a helmet. Risks and benefits may be exaggerated or discounted depending on the emotional response to the idea of a helmet.”
It’s not one or the other, we’re told
The story then goes on that there’s nothing stopping the advocacy of both helmets and cycling infrastructure. There’s two major problems m with this.
There’s little evidence that the people focused on promotion of bicycle helmets have also focused in any meaningful way on the promotion of cycling infrastructure. Even where they support cycling infrastructure, they still spend a undue amount of time of promoting gear. Time and focus are not unlimited. Focusing on one thing takes the focus off the other.
Barbara O’Connell, CEO of Acquired Brain Injury Ireland, is reported as reacting to the original story as saying: “People think when they come off their bicycles that they have been knocked off. For many people it could be a pedestrian stepping out in front of them, it could be a rock on the road or a pothole.” But the problem is that there’s no evidence of Acquired Brain Injury Ireland ever asking pedestrians to look out for cyclists or for road authorities to better maintain our roads.
The second problem with such claims is that you cannot have Dutch-style mass cycling and unchallenged heavy helmet promotion by the state. The people who claim helmets are not a barrier are the people who already cycle with helmets, or those who don’t understand what mass cycling on a Dutch-scale is, or those who put at best weak evidence to support helmets over solid evidence of the health benefits of mass cycling.
Individuals of course should be free to chose, but too many people see a major distinction between mandatory helmets and getting helmets stuffed in your face all the time, mostly with people so sure that you’re just an idiot. Recently people have started to imply that helmets are like vaccinations when that’s not the case. It’s worth noting that while he has debunked helmet research in one article, Ben Goldacre has spent a lot more time writing about anti-vaxxers.
For the record: I’d much prefer if I’d never have to write about bicycles helmets again, but I don’t have the obsession with them, I am defending against other people’s obsession of them. I’m not the one who put a flawed article on the cover on a national newspaper when said newspaper has failed in any way to report on, for example, councillors voting down cycle route proposals.