The telling death of a railwayman

Here, to keep you occupied while I work on something else, is a very short extract from a first draft of something else. It’ll need a bit of work. The context is that it comes amongst a long discussion of societal and judicial attitudes to dangerous driving, including the right to drive and our reliance on cheap road haulage and distribution with lax regulation, and illustrated with several of those case studies with which we are now all too familiar. (The pictures aren’t part of the extract, I’ve merely taken them from the Rail Safety and Standards Board Annual Safety Performance Report, and from STV news (warning: autoplaying audio/video)).

In 2011, a railway worker was killed. Just one. His name was John McInnes, an infrastructure maintenance worker who looked after lines in the north of Scotland. McInnes had thirty years of experience in a job that can come with all the hazards of working alongside fast trains, around heavy machinery, on high structures and amongst live wires. He was killed on the evening of the fourth of July 2011, while travelling to a work site on the Highland Main Line at Kingussie, only five miles from Crubenmore, where this whole story started. But McInnes did not die on the tracks. Accessing the work site by the A9 trunk road, his van and a car crashed with enough force to spark a horrific inferno that took firefighters 45 minutes to control.

This ironic tragedy highlights the already stark contrast between safety on the roads and safety on the railway. For more than a decade, railway workforce fatalities have been measured mostly at the low end of single figures, and five years have now passed without a single passenger or crew member having been killed in a train crash.

There wasn’t always such a profound difference between the safety cultures of the road and the railway. The navvies who built the Victorian railways were treated as expendable labour by powerful company owners who fought safety regulations, not only during construction, but also in everyday operation. Even when the railways were nationalised in the late 1940s, the toll on the workforce was still more than 200 every year. But strong unions demanding their right to safe workplaces, and public opinion demanding change when things go spectacularly wrong — as when major crashes occurred during the Railtrack era — has ensured that, these days, many layers of safety are built into every part of the railway.

The railway industry investigates not only all of the deaths on the tracks, but also the injuries and near misses below them in the Heinrich Triangle. The Rail Accident Investigation Branch makes extensive inquiries, consults the detailed operational records, and reconstructs events, leading to fifty page reports highlighting the lessons that are to be learned, the working practices to be revised, the rules which must be better enforced, and the new technology which should be adopted. The occurrences that it investigates are mostly what we would call accidents. Nobody was really to blame, and it is not the intention to find anybody to blame, only to prevent anything like it from happening again.

And so we have developed signalling systems which make it almost impossible to accidentally crash a train: train positions are automatically detected and the system keeps them apart by lengths of several train braking distances, refusing to allow the signaller to put trains on collision courses and automatically triggering the brakes if the driver fails to stop at red. Engineering work is checked and double checked and measured automatically by high-tech high-speed engineering trains on rolling schedules. In the event that engineering work must be carried out during live traffic, the engineering gangs work with dedicated trackside lookouts using flags and air horns to warn of approaching trains, while drivers sound their own horns until all workers have ensured their position is safe and signalled a clear acknowledgement in reply.

The railway has developed a culture in which staff at all organisational levels respect the fact that the railway is a hazardous work environment and that they must take seriously their responsibilities for the safety of their colleagues and passengers. But it did not achieve its enviable safety record simply by demanding respect and courtesy, and nor did it do so by imposing harsh penalties on workers whose momentary misjudgements ended in catastrophe. It designed a system which forgave those misjudgements: one which accepts that when humans are in control things will go wrong, so the system should be designed to allow humans to make minor mistakes and recover from them before there are any consequences.

In 2011, the Rail Accident Investigation Branch did not have to investigate a single worker death. John McInnes was on the road when he died at work, and when you work on the road, you’re still expendable labour.

Unskilled and unaware of it (re-post)

It was pointed out to me that I haven’t posted anything for weeks. It will be a few more before the project that has been taking up my time is out of the way. Here, then, is something I wrote way back in November 2010, which seemed relevant given the latest Department for Transport “please play nice on the roads” marketing campaign. If I were writing it today, I’d mention a million other things, and probably do away with the sarcastic transport mode tribalism that amused me so when this blog was young. But I’m not.

In the War Bulletin this week I mentioned a study that found drivers to be at fault in 87% of car/bicycle collisions.  According to the press release and coverage, the study included (but was not limited to) giving cyclists in Melbourne helmetcams, and analysing the footage of 54 “events”, including 2 collisions.  It sounds like the study has a number of limitations — it’s difficult to draw general conclusions about collisions from only 2 of them, and the results were only ever going to apply to the helmet-law and vehicular-cycling environment of Melbourne, and even then only to experienced cyclists who (presumably) were aware that that their own behaviour was being recorded.

The study was conducted by the Monash University Accident Research Centre, who I am sure did a good job.  But unfortunately nothing resembling it appears in their reports and publications, and I can find no evidence that the original research has been made public yet.  (Allowing the world’s media to uncritically churn your press release without being able to see the actual details of the work — and perhaps more importantly, before your fellow academics are allowed to review what you have done — is rather bad form.)  So there’s not really anything more we can say until we can see the study itself, and we may yet find that everything that has been said was wrong.

But the reported findings do fit with what we already know about accident causes and driver behaviour.

The Motorist attitude to their own collisions and near-collisions is a particularly interesting field.  When one suggests that speed cameras might be a good thing, for example, somebody will always pop up to declare that they have been driving at 90mph for decades and never caused a single accident, because they are a perfect driver who knows exactly when speed is appropriate. And it might be true: some people are good drivers and some people are bad drivers.  Trouble is, the driver himself can never know which he is: all drivers believe themselves to be above average.  Everybody is seeing bad driving, but nobody admits to doing it.

In Traffic, Tom Vanderbilt documents the details of the phenomenon of drivers unable to recognise their own lack of skill.  A large part of it he puts down to a lack of feedback.  For example, in the Monash helmetcam study, there were a mere 2 collisions, but there were 6 near-collisions and 46 “other incidents” (the classic Heinrich triangle).  These “other incidents” correspond to those situations where we notice people driving badly.  They occur because the driver failed to spot a hazard or failed to recognise as a hazard something that they did see.  By definition, if they did not see or did not recognise, the driver will never have been aware of the situation.  They will reach their destination assuming that they had done a great job, oblivious to the bad driving that had been recorded.  That’s probably what happened in 52 out of the Monash group’s 54 “events”.

And when the driver does finally notice that they have just been in a near collision, they can congratulate themselves for having the skill to have avoided an actual collision.

Thus reassured of their own driving skills, on the few occasions when they do get some feedback, they find ways to dismiss it.  That horn honk wasn’t aimed at me, or if it was, it must be because the other driver is an impatient egotistical bad driver who wouldn’t recognise good driving like mine.  The police pulled me over because they have a quota to fill, or because they’re anti-Motorist, not because I was driving dangerously.  After all, I already know that I am not a dangerous driver.

And then they crash, and it was an accident, bad luck, a momentary loss of concentration, beyond one’s control.  They couldn’t have caused it, because they already know from their experience and their long record of not causing accidents that they must be a good driver.

The evidence from driving simulation experiments shows that drivers can’t accurately remember what was happening in the lead up to the crash — what they saw and heard, who else was on the road and where and which order and when they appeared; what they were thinking and where they were looking and when they last checked their mirrors.  So they can unconsciously fill in these details with whatever makes them feel the least uncomfortable.

When drivers are shown videos of their driving (from helmetcams, or, as Vanderbilt discusses, Drivecam), most of them are surprised to discover that they have many more bad habits than they were aware of.  And that can create some uncomfortable cognitive dissonance for them, with attempts to deny or justify their behaviour, or, as with speeding, attempts to redefine it as safe.

It’s important to know these things about driver psychology if you’re trying to create a marketing campaign to make drivers be nice, or design ways to rehabilitate careless and dangerous drivers (how does sending a dangerous driver on their way with a £60 fine help anybody when the driver doesn’t have the skills to figure out what they are doing wrong?), or wondering whether to send your helmetcam footage to Roadsafe to be passed on to the offending driver.

And it’s important to know these things about driver psychology when deciding whether motor vehicles can ever share nicely with vulnerable road users.

After Westminster Hall, where next?

I have been neglecting this blog, both pulled away by other projects and watching with awe the unfolding of The Times‘ Cities Fit For Cycling campaign. I will assume that all of the readers of this blog have managed to keep up with those events through other sources, and have signed up and lobbied their representatives.

On Thursday afternoon, of course, the Cities Fit For Cycling campaign reached Parliament, with an excellent turnout of MPs enthusiastic for cycling and an astonishing degree of cross-party agreement about the things that make cycling unsafe and unattractive, and the sort of solutions that should be pursued. Unlike Boris “keep your wits about you” Johnson, the assembled MPs recognised that fast and busy roads are the main barrier to people making journeys by bicycle, and they recognised that Britain’s roads are not a natural and immutable phenomenon but things that we can alter to make less dangerous and more attractive for cycling.

There is, of course, only so much that backbench MPs can do, and the picture of Dutch-style cycling in Britain that one-by-one the MPs painted has so far been ignored by those who actually have the power to make a difference.  It is up to ministers to turn the debate into action, and the minister Norman Baker’s response to it all was, of course, embarrassing. Early Day Motions and backbench debates don’t, by themselves, change anything, and as Robert Davis and Cycalogical both point out, we should not be naive and think that the mere fact that this one debate has occurred means that we have received any of the things that were asked for.

But nor should we be too cynical and pessimistic: exciting things are happening. For as long as I’ve been writing about transport, cycling campaigners have tried to tell me that there is no point in asking for high quality cycling infrastructure because there isn’t the political will for it: there aren’t the numbers or the demand. Well the events this past year, and these past few weeks especially — the growing and multiplying flashrides and protests, the rise of cycling as an important London election issue, the Times campaign, and now the remarkably large show of MPs who really get it — have suggested to me that there are the numbers and there is the demand for change. Yes, promises have been made and broken before. But we know much more now — not least, of the alternatives that are possible. Now is the time to learn from those past failures, but not to learn that failure is inevitable. We must make sure that the issue remains at the top of our MPs’ agendas, and we must now set out exactly what ministers need to do, so that they can not fob us off with insufficient funds spent on inadequate things. This could be our “Stop The Child Murder” moment, but only if our efforts are sustained and focussed.

Norman Baker and David Cameron have already claimed their support with many words and few actions. It is, of course, obvious when poor Norman Baker is fobbing us off with a few pennies, barely enough for tiny isolated local incremental improvements; or when our MPs are trying to pass the buck to under-resourced local authorities. It needs to be equally obvious what real activity would look like.

The Times have set out the things that they think should be done in their manifesto. It’s a nice try, and identifying specific tasks for government — so that we can see clearly when they are or are not getting on with it — is exactly what we need to be doing. But The Times‘s list is not quite right. Chester Cycling has set out a better set of objectives for infrastructure, alongside an excellent set of principles for guiding policy discussions and keeping us on track.

My own list of tasks for ministers would place infrastructure at the top — because it’s the biggest, most expensive, and highest impact task — and look something like this:

Norman Baker’s department must get to work revising or replacing the engineering manual for cycling infrastructure — one of the most important promoters of crap cycle facilities and an active impediment to the import of international best practice — and changing the way that highways departments think about building for the bicycle (with the help of The Times‘s suggested “cycling commissioners”, perhaps). The Times are correct to identify junctions as the top priority for rebuilding, but unless we change the engineering manuals and culture, the rebuilt junctions won’t look any different from before. I will go into this in great detail in forthcoming posts.

The Times are absolutely right that funding needs to be redirected to cycling — more, even, than they specify (and taken from out dated relief road schemes). But of course large sums should not be handed out just to be wasted on substandard stuff that will need fixing later. In the first year, while a better engineering manual is being prepared, spending should be focussed on ensuring that we have the right expertise — the sort of expertise that Cycling England was just beginning to build up when it was cut — and that local authorities are ready to spend the money on something that actually sounds sensible and worthwhile when it does become available. Meanwhile, since almost everything that the DfT does is dependent on the Treasury thinking it’s a good idea, I imagine it would be sensible for Baker, Greening and The Times to be specifically working on those who hold the purse strings — making the case for serious and sustained investment.

The Times are right that 20mph should be the default urban speed limit, cycle lanes or not. 20mph is increasingly the urban speed limit, and most authorities would like it to be far more widespread, but 20mph zones are held back by the expense and bureaucracy of implementing it street-by-street. Given that this government is a fan of all that “libertarian paternalism” stuff — the latest being to make workplace pensions opt-out rather than opt-in — they should make 20 the default urban limit. Authorities would then have to go to the expense of opting out, consulting and erecting signs on the few roads where the appropriate limit is 30mph, rather than on the very many where it is 20.

The Times rightly identify big trucks as a problem. They suggest some sensible enough technological solutions to the danger they pose — alarms, sensors, safety bars, and the like — but bizarrely suggest that they only need to be present on trucks “entering city centres”. Vehicle design standards are generally handled by the EU these days, and my guess is that the EP is probably the best place to pursue this. However, there are steps that this government should be taking: standing up to the haulage industry’s relentless demands for bigger and heavier trucks, and pushing those big trucks back out of the city centres and narrow streets that should never have been expected to accommodate them.

There is one thing conspicuously absent from The Times‘s manifesto, given their focus on road danger and the many tragic stories that have been raised both in the newspaper and repeatedly by MPs who had lost constituents. They say nothing about getting dangerous drivers off the road. It is abundantly clear that in recent years we have developed a massive problem with the investigation of dangerous driving. Between us we could compile vast lists of hit and run incidents and near death experiences that have all ended in the police giving up because of lost files, untraceable number plates and the vehicle owner claiming not to have been the driver. Meanwhile, when cases of dangerous driving do make it to court, the sanctions are woefully inadequate. If the government were serious about tackling road danger, ministers from the DfT, Home Office and Justice department would be working on reforms to the policing and sentencing of dangerous driving.

Those are the areas where I think we should be expecting to see action from ministers, and I’ll go into more detail about each in later posts. The other items in The Times’s manifesto? Can’t argue with gathering more reliable stats on cycling: the “audits” that we’ve had in the past have usually been far from robust. Little to say about training: the funding for it is already adequate and protected, as ministers like to regularly re-announce (though I’m not sure why, given that vehicular cycling training has only been developed as a way to cope with their failed roads policies). And sponsored cycleways? A policy championed by Boris Johnson is the last thing cycling needs.

Prevention and cure

While organising notes, I stumbled upon this quote I bookmarked years ago, from the great Harvard cancer biologist Judah Folkman:

A pediatric surgeon in Boston just finished a difficult operation. To relax, he went to the Charles River and sat down on a bench. Suddenly, he heard cries of ‘Help! Help!’ and saw a person drowning. The surgeon jumped into the river and pulled the person to safety. He lay exhausted on the banks of the river and again heard, ‘Help! Help! ’ He glanced at the river and saw another person drowning. Despite his exhaustion, he jumped into the river and pulled the second drowning person to safety. Now, he was truly exhausted and lay on the ground huffing and puffing and again heard, ‘Help! Help! ’ He raised his head to look toward the river and saw a third person drowning, but he also noticed two basic researchers walking by the river. The surgeon shouted, ‘Colleagues, you must help! This is the third drowning person in the river in one afternoon! ’ The researchers looked at the river and then at the surgeon and said, ‘Three people drowning in one afternoon? This is very interesting! We’ll walk upstream to see who’s throwing them in!’.’’

(I think actually that it would work better if cast with public health researchers in place of basic researchers. The basic researchers would be too busy describing in obscure detail of the currents of the river, while translational researchers designed a better buoyancy aid for those currents.)

Folkman was applying the metaphor to his own field, cancer, but it works equally well for death and injury on our streets. The “road safety” approach to the problem has people studying the currents and advocating hi-viz vests and bicycle helmets, while spending billions on air ambulances and major trauma units. The “road danger reduction” approach goes upstream and asks why we are allowing large volumes of fast moving vehicles into the places where we live and work and play and learn. And it’s notable that in medicine, it’s the surgeons who think that preventing injury means bicycle helmets, and the public health researchers who think that preventing injury means calming and removing cars and trucks.

Here are a few of them: Danny Dorling talking about the open sewers of the 21st century; Harry Rutter’s Street Talk on moving towards a healthier city; and Ian Roberts, acting badly, on The Energy Glut. And you can hear Robert Davis talking about “road danger reduction” at London South Bank University on thursday next week.

During the 20th century, life expectancy lengthened by 30 years in the developed world. 25 of those years are attributable to public health intervention — to prevention rather than cure. But prevention disproportionately helps the poor and frequently hinders the rich. Guess which branch of medicine gets all the money.

Blijf uit de dode hoek

“Stay out of the blind spot”

Where have I heard that before?

Fixed that for you.

But these posters were repeated on a dozen lamp posts here:

It is, surely, irrelevant? Unlike London’s “superhighways”, there can’t be many Dutch roads left that could create this kind of situation, especially not in Amsterdam, where I spotted the avenue of posters. The kind of roads that carry big trucks generally give bicycles their own dedicated space; and the city streets where bicycles and traffic mix generally do not allow such big trucks. And in the few situations where bicycles and trucks could mix like this, the truck driver would not overtake the cyclist while preparing to make a turn (sorry, what am I talking about, these situations are always the dead cyclists’ fault for positioning themselves on the inside of a truck, never the surviving truck drivers’ fault for passing a cyclist while turning).

It’d be interesting to know how big a problem this really is in the Netherlands — and why the Dutch government (for I believe it was they) thought it important to put up posters about it.

In which I have to agree with the ABD

…that remedial lectures are not an appropriate alternative to prosecution for people who use mobile phones while driving. Stopped clocks, and all that. Rather less frequently than twice a day in the ABD’s case.

Lincolnshire, amongst others, are extending their remedial courses — the sort that are already widely offered as an alternative to prosecution for those caught driving too fast — to those caught using phones while driving. Greville Burgess, principal road safety coordinator for the Lincolnshire Road Safety Partnership, claims that such courses “could save lives”, but, this being a local newspaper, no evidence or source for the claim is cited. Burgess says:

“The evidence from other diversionary courses is very positive in that nationally less than 1 per cent re-offend within three years of completing the course. This strongly suggests that education rather than simple penalty points and a fine is more effective.”

But the latter does not follow from the former: Burgess does not give us the re-offending rates for those who take the penalty points. Is there really a statistically significant difference in rates at which people are caught — mark that, caught* — re-offending depending on which sentence they picked? But then, the utility of such numbers would be compromised anyway by the very fact that the offender picks the sentence: there is no randomisation in the groups we are comparing. The person who thinks that £60 and the points is the more lenient sentence might be very different to the sort of person who would rather spend £80 on the day-long remedial course. (Of course, both sentences look to me like absurdly light ways to deal with those who endanger the lives of others, but…)

This is the sort of intervention that is perfectly suited to a proper randomised controlled trial. While we’re at it, we could see whether combining the interventions — prosecution and remedial education — works better than either one on its own. If education really does work so well, why not make it a compulsory addition rather than an optional alternative to prosecution?

I don’t know what evidence Burgess thinks he has for his claim that these courses save lives, or are better than the alternatives, and I can’t find any likely candidates in the literature. But there is plenty of research on the topic, and a review of all the best evidence we have on driver education programmes — 32 properly randomised and controlled trials of advanced and remedial driver education programmes.  They found that the courses entirely failed to prevent re-offending.

And so far as I know, nobody has ever thought to investigate whether there might be side-effects to these policies. We have a prime-minister who sees moral hazard everywhere he looks, and is worried about whether we have sufficient deterrents to crime. We should not limit our assessment of driver education programmes merely to the rate of re-offending amongst participants. We must look at the wider and less immediately obvious effects of classifying mobile phone use while driving as the type of activity that merely merits spending a day getting a good talking to from a retired policeman. Perhaps there are no such side-effects. We don’t know until we look.

But I almost forgot. The prime-minister is also keen on some offenders being allowed their second chance.

I fear that this is now the second time I have found myself siding with the Association of British Drivers. But if I were to write about them every time they said something totally batshit crazy, I’d never get a moment’s rest.

* my own entirely unscientific observation is that, despite being universally recognised as extremely moronic behaviour, mobile phone use while driving is very common. The capture rate must be pretty embarrassing. I fear the 1% re-offending rate says far more about the efficacy of the policing than the efficacy of any remedies.

Risk compensation and bicycle helmets

Some months ago I left a series on bicycle helmets hanging while I got distracted with other things. We had looked at what the best evidence for the efficacy of helmets in preventing injury in the event of a crash is, and some of the reasons why we should be cautious about that evidence. We found that if you’re unlucky enough to have been hospitalised while riding a bicycle, you’re less likely to be there with a head or brain injury if you were wearing a helmet at the time of the crash. We noted several ways in which this protective effect is exaggerated and used to mislead, we noted that reduction in injury is from a very low level anyway, and that the research so far done fails to provide any sub-analysis of very different riding styles, such as racing cyclists, mountain bikers, and utility cyclists.

We also made careful note of the fact that a reduction in the rate of head injury in the event of a crash is a different finding to a reduction in the rate of injury and death of bicyclists. We briefly began the exploration of what this means by considering the fact that helmets are not much defence against a motor vehicle.

How could a reduction in head injury in cyclists who crash not mean a reduction in injury and death in bicyclists? Well, helmets could be causing other kinds of injury in crashes. Or they could be causing crashes — particularly the worst kinds of crashes.

The latter is a particularly interesting avenue. The idea is risk compensation or risk homeostasis, a phenomenon documented in fine detail by John Adams in the 1985 book Risk and Freedom. Adams showed that advances in road safety — seatbelts, motorcycle helmets, safer vehicle designs and wider, straighter, safer road designs — are never followed by quite the cut in injuries and deaths that is predicted; that while road “safety” has improved crashes are no less frequent, and that bystanders — pedestrians and cyclists — are butchered at an ever increasing rate.  There is a set level of danger that people are willing to tolerate, and so motorists were compensating for the new safety features by driving faster and taking more risks. To put it in Adams’s technical terms, potential “safety benefits” were instead absorbed as “performance benefits”.

James Hedlund reviewed the evidence on risk compensation and came up with a set of rules for when people are likely to compensate for a safety intervention:

1. They know it’s there.
2. They know it’s a safety feature.
3. There is a potential performance benefit to be had.
4. There is freedom to realise that performance benefit.

Well cyclists know whether or not they’re wearing a helmet, they know that helmets are meant for safety, there are potential performance benefits — riding faster, through smaller gaps, in more hostile traffic, or with less caution in conditions that would otherwise advise it — and cyclists are generally free to ride more furiously if they want to. (Indeed, you may be wanting to cycle faster, in which case go ahead and use a safety feature as a performance benefit if that works for you.)

But that’s only a hypothetical reason to expect risk compensation by cyclists wearing helmets, not evidence that it actually happens. And very little effort seems to have been put into researching that — perhaps because it’s difficult to devise a properly controlled test. A study of cyclists in Spain attempted to test the idea by comparing the rate of helmet wearing in traffic law violators to the rate in non-violators, finding that law breakers were less likely to be helmet wearers, the opposite to what they say should be expected if there is risk compensation. However, this study could not control for all possible differences between the populations (“confounding variables”) — for example, helmet wearers are already a population of safety-conscious conformists, less likely to commit traffic violations, and so a better question to ask would be whether those helmet wearers acted even more cautiously when their helmets were taken away from them, and whether the non-wearers behaved even more recklessly when given a helmet. (This study is, embarrassingly, the British Medical Association’s sole reference for their dismissal of risk compensation.) A more recent study observed a set of participants behaviour with and without a helmet, using speed as an indicator of risk taking and heart rate variability as a proxy for risk perception. This study found that when helmet users had their helmet taken away, the risk taking (i.e. speed) reduced to keep the risk perception stable. However, the study only looked at 35 people, and only looked at proxy variables. Neither study is very convincing — the limitations I describe here are just the tips of the icebergs — and certainly nowhere near strong enough or specific enough to guide policy. We still have a mere plausible hypothesis with no good evidence as to whether or not it’s true.

The authors of the Cochrane review acknowledge the suggestion that risk compensation by cyclists could affect their crash rate, but believe that is unlikely. It’s interesting to see a hypothesis dismissed with the argument from personal incredulity in a Cochrane review.

What is not touched on in the review, and which is potentially far more important (given the fact that crashes with motor vehicles are more likely to kill or seriously injure), is the risk compensation effect not of cyclists themselves but of the other road users around them — i.e., of the motorists. Look again at Hedlund’s rules. Motorists can see whether a cyclist is wearing a helmet; they know that helmets are supposed to be a safety feature; they can potentially find performance benefits — they think they can squeeze through tighter gaps when overtaking against oncoming traffic, or pass more quickly, or shoot in front while turning, because if they hit the cyclist then no harm is done; and there is nothing to stop them realising that performance benefit, since the police, if there even are any, are rarely even aware of the relevant traffic rules, let alone bothered with enforcing them. There is therefore a plausible hypothesis that motorists will take more risks around cyclists who wear helmets than around cyclists who do not.

This hypothesis is made all the more plausible by the fact that, in addition to potentially making cyclists seem less vulnerable, helmets make cyclists look more competent: in surveys of motorists’ beliefs, most assume that cyclists who wear helmets are more experienced and more “responsible“, meaning that they may be driving more carefully around non-helmeted cyclists who they expect to do something silly. And motorists overwhelmingly think that cyclists should be forced to wear helmets — presumably so that the motorists can get the performance benefits of driving more dangerously around them.

The motorist risk compensation theory has famously been tested by @IanWalker in one of the most delightful experiments in the field. Walker rode around Salisbury and Bristol on a bicycle fitted with an ultrasonic distance sensor measuring the effect of a number of variables on passing distance, including rider position in road, type of motor vehicle, and whether he was wearing a helmet. Analysis of over 2,000 passes showed that motorists tended to give on average around 5-10 cm less space when the rider wore a helmet. It’s not much difference, and the effect of motor vehicle type, perceived rider gender, and rider’s distance from the edge of the road were all stronger.

But it’s important to note that there is always a distribution of passing distances — a bell curve. There are a few motorists who give a lot of room, a few who scrape past, and a lot clustered in the middle, giving a little over a metre distance. When wearing a helmet, the bell curve shifts in a little bit. The cautious drivers give a little less space, the average drivers give a little less space, and the dangerous drivers give a little less space.  It’s the latter who are now more likely to drive into you.

Walker’s research, delightful as it is, is itself not without limitations. Most important amongst them is that, when it comes to answering questions of cyclist safety, it suffers the same limitation of measuring only proxy variables: passing distances rather than actual risk of crashes and injuries. But it tells us that there is a very important reason to study more than just the isolated risk of head and brain injury in the event of a crash.

Helmets are a medical intervention, exactly like a drug or surgical procedure. They are a preventative intervention and they are a physical intervention, but neither of those are alien to medicine and to the modern methods of evidence-based medical science. And risk compensation is just a side-effect of this medical intervention, like the side-effects of drugs. The side-effects of drugs that make it to market are by definition outweighed by the beneficial effects; but ten times as many drugs are discarded during development because the research finds that either the side-effects are so big or the beneficial effects are so small that the harm outweighs the help.

The authors of the Cochrane review defend their dismissal of risk compensation by saying “the fundamental issue is whether or not when bicycle riders crash and hit their heads they are benefited by wearing a helmet.” And that’s fine if you’re in the preliminary stages of developing an intervention and you are so far only concerned with whether it has beneficial effects. But the authors go far beyond that early stage in their conclusions, recommending that this intervention be compulsory — despite there being very good reasons to suspect that there are potentially major side-effects of this intervention. They can’t have it both ways. If you haven’t bothered studying the side-effects you can’t license the drug. It might kill people.

Can drivers be taught a lesson?

M’coblogger Ed thinks there is a case for teaching drivers to behave — specifically by appeals to patriotism. Education programmes are a popular idea amongst cyclists, cash-strapped councils, and road safety types. I dismissed them as a solution that doesn’t work in my own post on revenge and road danger, but didn’t go into any detail. So I thought I better ask: what’s the best evidence we have about driver education programmes?

Remember what I said about bicycle helmets. It may be common sense that teaching drivers will make roads safer and nicer places to be, but common sense is frequently wrong, and cures can kill if they’re based on common sense rather than evidence. Trying to educate drivers could make the roads safer and nicer. It could be entirely ineffective. Or it could make them more dangerous and less pleasant. Until we conduct a controlled trial, we don’t know which.

There are two systematic reviews from the Cochrane Collaboration looking at the effectiveness of driver education programmes.  Cochrane reviews are, remember, the independent synthesis of everything that we know about a particular intervention, and are considered by doctors to be the closest thing we can ever get to fact.

The first Cochrane Review looks at the effectiveness of driver education in existing drivers. The schemes that have been trialled particularly focus on advanced driver training — the sort of programme that is designed to improve hazard detection and reduce error making, and which is frequently recommended for professional drivers — and on the remedial programmes that are increasingly offered to drivers who break the rules as an alternative to a driving ban.  These are lessons and lectures rather than marketing campaigns, but the remedial programmes — lectures on why speed limits matter — are particularly relevant to the “be nice” approach to making our streets nicer places where people feel able to ride bicycles.

The review found 24 trials from 1962 to 2002, all in the US except for one in Sweden, with more than 300,000 participants between them.  With those sorts of numbers, there is little chance of the review accidentally getting a false result.  Four were for advanced driving courses, the rest for remedial classes.  The programmes ranged from the simple supply of written material (9 trials) — a letter and copy of the rule book — through group lectures (16 trials) to proper one-on-one classes (7 trials), but all were designed to improve “driver performance and safety”.

The trials typically checked up on participants two years later and compared the rate of rule breaking and/or the rate of crashes in those who received the education programme and the controls who did not.  There was no difference. The education programmes didn’t stop drivers breaking the law or having crashes.  The authors concluded that companies shouldn’t bother with driving courses for their staff, but should let them take the train instead.

The evidence reviewed isn’t perfect. They could not, for example, blind participants as to whether they were in the study or control group. And the conclusions apply to the 32 specific advance driving courses and remedial classes that were trialled — we can not say for sure that other types of education campaign wouldn’t work. But the evidence tells us to at least be very wary of investing in any campaign strategy that relies on teaching people to play nice.

The second Cochrane review looks at the effectiveness of educating school kids before they start driving.  These are the sort of programmes that are supposed to address the fact that 17-21 year old drivers are twice as likely to crash as the average driver. They are particularly popular with the Road Safety industry and there are several varieties common in this country.  Indeed, I have first hand experience: it must have been during the final GCSE year, aged 15 or 16, that we were all taken to the Bovington tank training circuit to take it in turns driving hatchbacks (sadly no tanks) around the track, doing hill starts, three point turns, reverse parking, and, as a treat afterwards, emergency stops from 70mph. While not everybody is privileged enough to get real practical lessons, the government does at least make sure that kids are taught how to get a learner’s license and find an instructor, what tests they will need to take, and are given a few road safety messages.¹ *

The Cochrane review found three RCTs with a total of around 18,000 students. The review looked at the public health outcome of the trials, typically measured as the rate of crashes and/or violations in the first few years of holding a license. Giving school kids driving education did not reduce the incidence of crashes and violations.

Indeed, the authors, against common sense, found evidence of the opposite. The reason can be found in the other outcome that the trials measured: the time it took the kids from turning 17 (or whatever age was relevant in their particular locality) to passing their driving test (which the study gives the awful name “license delay”). Kids who were given driving classes at school were more likely to seek and obtain a license, and they did so earlier — and we already know that age correlates with crash rate and rule breaking (or at the very least, being caught and punished for rule breaking).  Driving classes in school weren’t making people drive safely, but they were making people drive.

You can see why driver education programmes are so popular with the road safety industry, puppet of the motoring lobby. The trials reviewed by Cochrane were all from the mid 1980s, yet we continue to put money and effort into programmes that are worse than useless. My own school driving lesson was fifteen years after school driving lessons were shown to be harmful to our health.

Whenever questioned, the government cites as justification its own non-controlled study which showed that kids are able to recall and are vaguely more likely to agree with specific road safety messages when asked three months after the lessons. No, really. That’s it.¹

So drivers can be taught. They can be taught, before they even become drivers, that driving is normal, just something that everybody does. The moment I turned 17 I wasted about a hundred quid on driving lessons before I stopped to ask myself why. Everybody was doing it, right? You do GCSEs at 16, driving at 17, ‘A’-levels at 18. That’s how it works.

Perhaps they can be taught to behave and we just haven’t worked out how yet. There are not, so far as I am aware, any trials on the effectiveness of making motorists try cycling on the roads. But I suspect even that would have limited effect, and maybe even that could backfire too.

Because people generally don’t do what they’re told to do, they do whatever looks normal and natural and easy. You can call that selfish and lazy if you like, but I don’t think that will help you understand or overcome the behaviour. In the UK it is normal and natural and easy to learn to drive and then drive badly. And people refuse to be taught that the things which are normal and natural and easy, the things that everybody around them is doing, are wrong. Experience trumps the word of others.

In the Netherlands, incidentally, cycling is normal and natural and, thanks to the infrastructure, easy. In the UK it’s none of those things. Make it easy and you’re nine tenths of the way to making it normal and natural.

Revenge and road danger

Almost all cycling campaigners agree that a cycling society — “mass cycling” — would be desirable. The world would be a better, happier, healthier, wealthier place, and our towns and cities nicer places to live, if far more people cycled and far more of our journeys were made by bicycle.  And there is little controversy left about the barriers to cycling and the fact that fear of traffic and hostile conditions for cycling are the biggest and most impenetrable barriers to cycling in this country.  Large volumes of fast moving and dangerously driven motor vehicles create an environment in which most people never cycle.  This is old ground I shouldn’t need to go over again.

The big disagreement is how we break down that barrier. One set of campaigners want to separate the large volumes of fast moving motor vehicles from cyclists.  The other thinks that there is a better way: separation is unnecessary and perhaps even undesirable.  Their alternative is to tame to motorcar.  They would teach drivers how to overtake properly, how not to park in dangerous places, and how not to drive a tipper truck all the way into the advanced stop box while preparing for the left turn at the change of the lights.  And if they demonstrate that they can’t be taught, ban em and bang em up.  Teach drivers to play nice and the barrier to cycling will tumble, the argument goes.

As a typical cycling forum poster puts it:

I don’t even know why the councils in this country bother with cycle lanes. The money would be better spent educating idiots on the road on how terrifying them driving 6 inches from us at 50mph is.

It’s a response to the road danger problem that I have every sympathy with.  Every time somebody passes within touching distance I want to reach out and touch, and cause damage or inspire a little of the fear and discomfort in return.  I usually can’t watch helmet cam footage: I know that something bad is going to happen and that somebody is going to get away never accepting that what they did was wrong.  I desperately want them to know just what a fucking terrible thing they did.

The world in which tame motor cars roam the streets is a world in which every evil, selfish, or simply ignorant motorist has been made to realise that they have done wrong and made to feel shame and remorse for all those times they nearly took a life.  It’s a world in which we get our revenge on all those individuals who wronged us.

The problem is that road danger isn’t really all about individuals.  Ian Roberts describes this peculiar way of thinking about road danger in The Energy Glut: our focus on individual “accidents” and the individual who is to blame.  The pedestrian who jaywalked, the drunk driver, the person who made The Bad Judgment to cause it all.  And when it costs a life, we want revenge for That Bad Judgment.  This is how we think in the “road safety” paradigm: something went wrong, and we can educate, engineer, or enforce that out.  The Human Being and the Motor Car are perfectly able to peacefully coexist, it’s just that idiot needs dealing with.

It’s a nice idea.  But it doesn’t work.  Revenge won’t solve the road danger problem.  Education can’t solve it.  And “road safety” should have been written off decades ago.

For six decades road deaths and injuries have primarily been reduced simply by the human beings getting out of the way.  Education, engineering, and enforcement have had at best a minor role in cutting the rate of death and injury to cyclists over the year.  What really cut the number of deaths to cyclists was people stopping cycling, leaving only a few of the most confident, assertive, and powerful on the roads. Even those of us left have cut our distance, and set personal limits on the sort of roads we’re willing to ride on.  The Human Being and the Motor Car do not peacefully coexist.  The Human Beings get out of the way.

Why won’t revenge, education, and road safety eliminate road danger and make the roads a nice objectively and subjectively safe place to ride?  Because road danger isn’t all about the individual and their preventable mistakes.  Sometimes the pedestrian wasn’t jaywalking and the driver wasn’t drunk.  The “accident” happened simply because putting metal with that sort of kinetic energy — even the kinetic energy of a 20mph car — right next to soft fleshy people who are going about their daily lives is dangerous in any situation, no matter how well everybody behaves.  Death and injury is an inevitable result of mixing people and motor vehicles.  Idiots can make it even more probable, but it will always happen.  Ian Roberts goes right ahead and blames the car lobby for suppressing any thoughts that the car, rather than a few rogue users, might be an inherently dangerous thing to have around — but you really must read the book for that story.

Even if it were possible to weed out all of the bad apples, there will always be enough road danger to put people off cycling.  But realistically it’s not even possible to weed out all of the bad apples — or to force them to be good.  It is frequently claimed that “strict liability” will enforce good behaviour, and even that it has been proven to work — just look at the Dutch, they have strict liability and there’s loads of cycling there.  It’s another very attractive idea: if you come near me with that thing, you’ll pay.  I think most British cyclists see “strict liability” and salivate at the idea of that idiot, desperate the overtake through that little gap at 50mph, being forced to sit there and suppress his urges.  We taste that sweet revenge again.  But the real idiot won’t wait.  As David Hembrow points out, the Netherlands has idiots too.

That’s not to say that there is no reason for enforcing the rules, punishing the wrongdoing, improving driver education, and ensuring justice for the wronged. Only that those are not the things that will bring us closer to a world where mass cycling can happen.

Vengeance is no way to go about establishing productive policy, no matter how desperately we yearn for it.  Policy needs to be based on what works, and when it comes to establishing mass cycling we can try any number of policies, but as long as we are asking squidgy and snappable humans to share with hard objects possessed of such large quantities of kinetic energy, none of them ever will.  Get rid of those hard objects — separate them off — and we can make progress.

A vaccine for road safety

I stumbled upon this infomercial from BBC World while looking for something to entertain me over dinner:

It’s always fascinating to see how a television documentary treats a subject that one has spent some time looking at — in this case, motor vehicles and public health.

The one little specific aspect of motor vehicles and public health that the documentary looks at is the problem of “road safety”, particularly in the poorer parts of the world.  Well over a million people die on the world’s roads each year, disproportionately poor people killed by or in the name of rich people, putting road danger alongside those similarly neglected poor people’s problems, malaria and tuberculosis, in the public health league tables.

The documentary looked at the sort of interventions that can be made to reduce road deaths.  They are interventions that the UN has backed as part of the “decade of action” on road safety, and which the World Bank is now helping to fund.  They seem to fall into two categories: engineering and education.

The reasoning behind an engineering campaign is that it has been observed that some road designs see more deaths than other road designs.  Motorways, with their regimented traffic, central reservations and hard shoulders, have fewer fatalities than roads that pitch opposing traffic head on, separated only by a bit of paint.  Therefore, the World Bank will replace the dangerous streets and roads of the developing world with motorways.  Some of you might already be mumbling something about confounding variables, and safety being achieved simply by driving vulnerable road users away with hostile environments, but shut up you ingrates, it’s a gift, for their safety.

Unfortunately, they are discovering that even when you build these fantastic new eight-lane highways, no matter how much you teach the kids the green-cross code, the bloody fools still misuse them. “The irony is, that freeway is supposed to serve the people, in whatever form that takes.” So the kindly international road safety folk are building pedestrian overpasses. They’re not even going to ask why people are trying to cross their shiny new road. Are they trying to get to their workplaces? Their school, or shops, or market? Their few remaining fields? What kind of a moron builds their house on one side of a motorway and their school on the other?  You might ask whether it’s worth expending money on people who make such an elemental mistake.  But the road safety folk are so nice they will provide a foot bridge just like that — no awkward questions asked.

The reasoning behind an education campaign is that it has been observed that many of the people who are dying are pedestrians and “two-wheeler” users, doing silly reckless things like running from one side of the road to the other, or putting themselves in the way of vehicles without first encasing themselves in armour.  Did you know that in some of these countries they don’t even have hi-viz?  Even some drivers are endangering themselves by not wearing a seatbelt.  The only possible conclusion is that these people are ignorant of the risks that come with running across a motorway, and the benefits to be had from wearing helmets and seatbelts.  If only we could reach out and let them know…

“Enforcing drink driving laws, making people wear seatbelts, toughening up on vehicle maintenance standards, these are all basic affordable things,” the presenter tells us.  If only our own government thought so.

Unfortunately, enforcement seems to be a slip of the tongue.  This doesn’t appear to be about enforcing drink-driving and seatbelt laws, but about educating people about the dangers of drink-driving and the merits of seatbelts.  And simply telling people how to do something that they don’t want to do is at best an inefficient route to behavioural change.  This has been shown time and time again, study after study shows that telling people — whether child pedestrians or experienced drivers — to do specific things in order to be safe on roads just doesn’t work.  (See e.g. the review drawn up for NICE, the UK body which decides whether proposed health interventions are worthwhile.)

The one thing that road safety education does achieve, of course is good PR for the company that is funding it.

The BBC documentary doesn’t say who is behind all this stuff. A few representatives of development NGOs pop up, we visit the UN, who have put their name to the “decade of action”, and we know that the World Bank will be amongst those building roads. But we don’t really hear from the concerned and benevolent folk who persuaded the UN and World Bank to spend all this money on bigger safer roads.

Michelle Yeoh, presenter of the BBC item, is global ambassador for road safety at the “Make Roads Safe” campaign.  That campaign is the public facing side of the “Commission for Global Road Safety”, itself a part of the FIA Foundation.  The FIA Foundation in turn being the independent charity funded by the Fédération Internationale de l’Automobile, the international automobile lobby.

Ian Roberts describes who the commissioners on the Commission for Global Road Safety are:

Canada is represented by an Executive Director at General Motors, Japan by a Board Member of the Bridgestone Corporation, the major trans-national tyre maker. Russia is represented by the President of the Russian Automobile Federation and Italy by a former president of the Automobile Club of Italy. Michael Schumacher represents Germany and France is represented by Gerard Saillant, Deputy President of the FIA Institute, another FIA creation and responsible for the medical aspects of Formula One. The UK Commissioner is the Chief Economist at Lehman Brothers, a US investment bank with financial links to Formula One. The US Commissioner is Director of the Global Road Safety Forum, an organization funded by the FIA and one of the ‘implementation partners’ that the Commission works with. The Commission’s Patron is Prince Michael of Kent, a former racing driver, now a member of the British Racing Drivers Club and the Bentley Drivers Club. Lord Robertson himself is Deputy Chairman of the Board of TNK-BP, a Russian oil company. According to the Lords’ Register of Interests, which shows that the FIA paid for Robertson to attend the 2006 Monaco Grand Prix, the Commission meets at the races.

In a response to Roberts’ paper about the Commission, the FIA Foundation reminded us that it “has no relationship with industry whatsoever”.

At Bath Skeptics, Ian Walker, referring to British road conditions, stated that anybody who has to use the roads as part of their job is working in Dickensian conditions.  Health and Safety regulation means that death in the workplace is exceptionally rare in Europe today, and when it does occur, it is typically followed by extensive investigation to discover what went wrong, whether anybody was to blame, and how to prevent it ever happening again.  Unless the workplace is a road, in which case death is routine, nobody is to blame, and nothing can be done about it.  If you drive as part of your job, you are expendable labour.

One of the reasons that Europe’s workplaces are so safe, of course, is because we have simply outsourced the dangerous jobs.  The poor of Africa and Asia, free from health and safety laws, are mining our minerals and weaving our clothes for pennies, working in real Dickensian conditions, and the World Bank needs to build big roads so that they can drive the products to the docks.  Like Victorian mill-workers, the third world should be grateful for the kindness showed by their new bosses in providing such safe new roads, servants of the people.

Would a helmet help if hit by a car?

This post is part of a series: it starts with the intro to the helmets issue, then the summary of the best evidence on helmets, then a quick diversion into how dangerous cycling is and an attempt to define terms. And there’s more…

Brake, the “Road Safety” charity, say yes:

Helmets are effective for cyclists of all ages, in crashes which do and do not involve another vehicle.

That matters, because if cycling safety is in the news, journalists will go to Brake for an easy quote.

The British Medical Association also say yes:

Helmets provide equal level of protection from cars (69%) compared to other causes (65%)

This is important, because the BMA is a highly trusted organisation with political influence, and their current policy is to endorse the criminalisation of riding a bicycle when not wearing a helmet.

Interestingly, president of the Automobile Association Edmund King, who was giving away free advertising bicycle helmets in London this week, disagrees with the nation’s medics on both issues:

We don’t think helmets should be compulsory but we think there are benefits… Our view is that helmets do not protect against cars but they may protect against some of the 2.2m potholes which often are the cause of smashes into the ground by cyclists.

Carlton Reid adds a little detail:

Most bicycle helmets are designed for falls to the ground from one metre at speeds of 12mph. They offer almost zero protection in collisions between bicycles and fast-moving cars.

The risk reduction provided by helmets in bicycle crashes that do and do not involve motor vehicles is one of the few sub-group analyses that was performed in the case-control studies that are covered by the Cochrane Review, and it’s no surprise that this is the source for the BMA’s claim. In bicycle hospitalisations that did not involve cars it reported nearly 70% fewer head injuries in the helmet wearers. In bicycle hospitalisations that did involve motor vehicles there were nearly 70% fewer head injuries in helmet wearers.  A helmet is equally effective at preventing head and brain injury in crashes with cars as in solo crashes.

What makes Edmund King and Carlton Reid think they know better than the nation’s medics and road safety campaigners?  Indeed, what makes them think that they can go around claiming the opposite of the cold hard corroborated stats of the Cochrane review?

Well actually, they’re not. Not quite. King and Reid are judging helmet efficacy by a slightly different metric to the Cochrane Review.  The Cochrane Review is the looking at the set of bicyclists who have had an accident of a severity that hospitalises but does not kill outright.  The review says nothing about deaths, for example, and as the Cochrane Review itself notes, more than 90% of cyclist deaths are caused by “collisions” involving moving motor vehicles (the same proportion is found again by a separate route in the TRL review and again in NYC).  But only 25% of hospitalisations were caused by motor vehicles.  And while Cochrane suggested a whopping 85% of head injury hospitalisations (which in turn account for around half of all cyclist hospitalisations) could be avoided by wearing a helmet, the TRL review of post-mortem reports found that only 10-16% of all cyclist deaths might have been avoided.  Hospitalisations, of the sort reviewed by Cochrane, are not representative of deaths.  Fall off your bicycle and you might get hurt.  Get hit by a car and you might die.

That’s because when you fall off your bicycle, chances are you are toppling over some way — precisely the sort of simple fall that a helmet is designed for, and the sort of fall that is least likely to cause life-threatening injury to any other part of the body.  When hit by a car the body might be crushed, or thrown up and around at speeds that helmets are not designed for, and so there are many more opportunities to suffer fatal trauma to other parts of the body.

(As an aside, Brake actually get this one the wrong way ’round:

Nearly 50% of cyclist admissions to hospital are for head and facial injuries, and the majority of cyclist deaths and injuries are a result of head injury.

TRL has the answer to this one: around three quarters of cyclist fatalities did indeed involve a serious head injury.  But only about a quarter involved only a serious head injury.  The rest also involved one or more additional life-threatening injury.  The Brake claim is at best misleading.)

This doesn’t mean that the BMA and Brake are all wrong* and King and Reid are completely correct.  A car at speed may be able to cause the sort of multiple trauma that merely falling over doesn’t, but that doesn’t mean that cars aren’t also capable of causing the sort of crashes that helmets are designed for, especially in low speed city traffic.

So Edmund King is wrong**.  But within the untruth he is communicating an important truth: cars are responsible for the most serious injuries and death, and helmets will rarely help in those cases.

Brake and the BMA are correct.  But their strictly truthful statements hide the crucial details, without which they are liable to seriously mislead.

* Indeed, they can’t be wrong.  You can provide a hypothesis for why helmets might be useless in crashes with cars, but no hypothesis can trump the real world stats that say helmets are useful in crashes with cars.

** Carlton Reid is not wrong, because he specified fast-moving cars.

Headline figures

If you haven’t done so already, start from this post and work your way forward.

In rare events like bicyclist injuries, odds ratios can be used as an approximation of relative risk: that is, how much a medical intervention changes the risk of a specific outcome.  An odds ratio of 0.3 is interpreted as a 70% reduction in risk of head injury when wearing a bicycle helmet.

The Cochrane Review looked at five studies, which contained a number of sub-analyses.  There was actually a range of odds ratios found when looking at different types of injury in different groups of cyclists.  In one, an odds ratio of 0.15 was reported.

So now the headline figure is that bicycle helmets protect against a whopping 85% of injuries.  Imagine the lives that could be saved.  Won’t somebody think of the children?  The 85% figure is constantly repeated by “Road Safety” spokesmen, and reported without context by journalists.  It’s cited by the British Medical Association in support for banning people from riding bicycles except when wearing helmets.  The 85% figure matters.

Leaving aside questions over whether the 85% figure represents the real efficacy of helmets, how useful is it as a guide for how to live our lives?  Well, as Ben Goldacre puts it: “you are 80% less likely to die from a meteor landing on your head if you wear a bicycle helmet all day.”  Nobody has ever died from a meteor falling on their head*.

What Ben is saying is that relative risk is only a useful number to communicate to the public if you also communicate the absolute risk.  If you want to know whether it’s worth acting to reduce the risk of something bad happening, you need to know how likely it is to happen in the first place.

In the UK, 104 cyclists died on the roads in 2009, according to DfT stats.  It was 115 in 2008, but the trend has been downwards for a long time.  For simplicity, lets say that in future years we could expect on average 100 cyclist deaths per year.  It’s really difficult to say how many cyclists there are in the UK, because you can define it in several different ways, and even then the data that we have is crap.  You can estimate how many bicycles there are, but these estimates vary, many bicycles might be out of use, and many of us own more than one.  You can take daily commuter modal share — which would give us 1 million cyclists — but there’s more to using a bicycle than commuting, and most people mix and match their modes.  According to the latest National Travel Survey, 14% of people use a bicycle for transport at least once per week.  An additional 4% cycle several times a month, and 4% again cycle at least once a month.  Cumulatively, 32% of the British people cycle at least sometimes, but some of those are too infrequent to be worth counting.  To be generous, and to keep the numbers simple, I’ll round it down to 16%, giving us 10 million on-road cyclists in the UK.  That means one in 100,000 cyclists is killed in cycling incident each year.

To put it another way, there’s a good chance you’ll get killed if you carry on cycling right up to your 100,000th birthday.  (If you do not first die in the inferno caused by the candles on the cake.)  Or, if when Adam and Eve first left Africa 200,000 years ago they had done so on bicycles, there is a good chance that at least one of them would be dead by now.  Alternatively, if you accept that life expectancy is around 80-90, make the unlikely assumption that all cyclists remain cyclists pretty much from cradle to grave, you might die cycling once in over a thousand lifetimes.  Nine-hundred and ninety-nine lifetimes in a thousand, you will die of something much more probable.  Like heart disease, or cancer.

But not everybody who dies on a bicycle dies of head injuries, and not everybody who dies of head injuries sustained while riding a bicycle would be helped by wearing a helmet.  The DfT/Transport Research Laboratory have done their own extensive review of the medical literature on helmets and say: “A forensic case by case review of over 100 British police cyclist fatality reports highlighted that between 10 and 16% of the fatalities reviewed  could have been prevented if they had worn an appropriate cycle helmet.”  This is because, while some form of head injury was involved in over half of cyclist fatalities, the head injury was usually in combination with one or more serious injury elsewhere on the body; and even in those where only the head sustained a serious injury, as often than not, it was of a type or severity that a helmet could not prevent.  There are, of course, many caveats and limitations of such an estimation, which relied on many assumptions, some amount of subjective judgement, and a limited dataset which was biased to the sort of cyclist fatalities that the police are interested in.  So we could be generous and round it up to 20% — that helps keep our numbers simple.

So we’re talking about about 20 lives saved per year, or in terms that matter to you, your life saved if you cycled for half a million years. Of course, a third of British cyclists already wear helmets, so we can add the number of cyclists whose lives are already being saved.  We could be generous again and say 40 lives per year.

That would give you a chance of less than 1 in 2,500 that, as a cradle-to-grave bicycle user, bicycling from nursery school to nursing home, you will die in a crash that a helmet would have protected against.  The chances are 2,499 in 2,500 that you will die of something else.  Like the 4 in 2,500 chances of being killed in a cycling incident where a helmet would not have helped.

Or the 6 in 2,500 chances of death by falling down stairs.  Or the 3 in 2,500 of being run over by a drunk driver.  Or the whopping 30 in 2,500 chances of dying of an air pollution related respiratory disease.**  Unfortunately I couldn’t find the British Medical Association’s policy on legal compulsion for users of stairs to wear appropriate personal protective equipment.

Of course, in addition to the 100 cyclists killed on British roads each year, another 1,000 suffer serious but non-fatal head injury, sometimes involving permanent and life-changing brain damage (as do users of stairs).  The Cochrane Review says that up to 850 of those injuries would be avoided or less severe if a helmet were worn; the more pessimistic TRL review says that perhaps 200 of them might be prevented or mitigated by an appropriate helmet.  Either way, we’re still in the area of many thousands of years spent cycling.

Whether you think those numbers make helmets worthwhile  it is up to you — I don’t think these numbers alone objectively prove that helmets are or are not worth using.  Just don’t be fooled by the stark headline-grabbing figure of 85% risk reduction.  When the absolute risk to begin with is smaller than that for fatally falling down the stairs, and a fraction of one percent of that for cancer and heart disease, consider whether risk reduction matters.

Of course, that might all change once we’ve looked at the next part of the story…

–

* I have not checked this fact, which I just made up, but I would be surprised to hear that it is not true.

** Hastily googled and calculated headline figures for illustrative purposes only; again, I have not thoroughly assessed these.

Final disclaimer: this is a hastily scribbled blog post, not an academic paper.  I’ve checked my zeroes and decimal places, but if I’ve overlooked something or accidentally written something to the wrong order of magnitude, please do point it out.

Just Stay Indoors

How best to get the road safety message to the yoof of today? A catchy hook? A rap? Too passé. A cartoon? Too juvenile. What about zombies. Brilliant. Depict an apocalyptic world populated by undead victims of road traffic accidents. The kids will love it. Or be too terrified to ever leave their homes. But that’s a risk you take if you’re Newcastle City Council. The first line of the council’s new Road Safety website states:

Traffic is the single biggest cause of accidental death for 12 to 16 year olds.

The second is suicide. Being a teen is ace! Alongside gory, gratuitous mocked up photographs of zombified traffic victims, are tabs on cycling and pedestrians. These are divided into facts and, er, survival skills. Because transporting oneself outside of a vehicle is that dangerous. Here are a few of those facts.

• Teenage boys are six times more likely to be killed or seriously injured on bikes than teenage girls.
• Young people aged between 11 and 16 are more at risk of being killed or seriously injured as a pedestrian or cyclist in road accidents than any other age group.
• Wearing a cycle helmet can improve your chances of survival, and reduce the chance of serious injury.

Firstly, your chances of being killed as a cyclist as ridiculously low. Far, far lower, than as a motorist. There were 104 pedal cyclist fatalities in 2009. To begin a section on cycling with the assumption that YOU MAY DIE is to basically scare off a generation of teenagers from forming walking and cycling habits that could become embedded in part of a healthy lifestyle.

In a similar vein, the section on walking warns teens that:

• Young people aged between 11 and 16 are more at risk of being killed or seriously injured as a pedestrian or cyclist in a road accident than any other age group.
• Traffic is the biggest cause of accidental death of 12 to 16-year-olds.
• 1 in 5 teenagers report having been involved in a road accident.

Again, I see this as scare-mongering – in addition to being told that if they walk home late at night they will be kidnapped and murdered, they will now also be mown down by vehicles, unless they drive or board them.

Why are the council ploughing money into an “edgy” campaign that will only serve to turn teens away from cheap, healthy modes of transportation? People who start walking and cycling in their teens, generally keep walking and cycling. I’ve lost count of the number of peopel I’ve met in their twenties who want to cycle, but are unsure of where to start, and wish they had kept it up instead of stopping once they hit 13. Cycling isn’t dangerous, if you teach drivers to look out for cyclists properly, and if cyclists feel safe on roads. Similarly, if pedestrians have places to cross, they don’t get run over.

A savvy website may grab attention, and make the council feel “hip”. Unfortunately, the cost of outreach schemes, when the health service is overstretched due to heart disease rates skyrocketing years down the line is a lot harder to predict.

–Dawn

Weekly War Bulletin, 18 Sep

This week, a report by Professor Obvious, commissioned by the Department for Transport, found that Motorists feel a great sense of entitlement to the road and will throw their toys around when they don’t get what they think they’re owed.  Like the van driver who cut out in front a cyclist, threw a bottle when the cyclist pointed out the quality of the driving on show, and subsequently got fined because it was all on film.  This last development is likely to alarm the readers of the Daily Mail who, usually so keen to dictate how others should behave, are getting rather worried about Sussex police’s plans to Big Societise traffic policing, with the public encouraged to report each-other’s bad behaviour on the road.

George Michael “gasped” when told he was to be locked up for a mere four weeks, having admitted getting wasted on what the BBC delightfully describes as “cannabis cigarettes” and driving his three ton truck around central London — by pure good fortune crashing it into a Snappy Snaps before he could drive it into a person.  We share your astonishment, George.

Two young offenders have fled detention on their cycle proficiency bikes.  Their choice of getaway vehicle is yet more evidence, as though it were needed, that cyclists are selfish, anti-social, holier-than-thou, road-hogging pavement thieves.

RoadPeace are fighting against those in the “road safety” industry who will try to blame the deaths on our streets on anything — headphones, poverty, texting — except cars and drivers.

But: it turns out that breaking the speed-limit is officially morally OK after all, because the government lied about how likely you are to kill a child at 40mph.

And the London Cycling Campaign want to spend £20,000 on posters asking people nicely if they wouldn’t mind just being a bit safer when they drive their lethal vehicles around entirely inappropriate streets.

Permission to pave a cycle path in Putney Common is denied because of a rule that the area must be kept natural and free from human influence.  A3 dual-carriageway is exempt from that rule for obvious reasons.

Nobody uses TfL’s guided rides to work.

Mayor makes special arrangements for pampered director of centuries-old wealth-hoarding organisation to get driven around London without paying the CCharge.

Not really news, but the Telegraph has some impressively large contextless numbers on the copper-wire theft that is the cause of signalling failures.

This week saw the first casualty of note on a hire bike.  More interestingly, the Standard now seems to think that the hire bikes are known by a compound noun, “Borisbikes”.

The Campaign For Better Transport makes the dubious claim to have objectively measured the car-dependence rate of major British towns and cities, finding Nottingham least car-dependent, and Milton Keynes most car-dependent.

Lewisham, a borough seeking to cut its budget by 25% — £60m over 3 years — is having a laugh playing with fantasy Bakerloo Line extensions.

Billboard posters of woman in underwear will not cause car crashes.  That’s OK then.

Poor Brian Coleman, the Motorist’s friend in London, has had his taxi allowance cut.  What will he do next time he gets banned for speeding?

In a letter to Nature, biologists warn of plans to build a highway across the Serengeti: the road would cut the migration routes of large mammals like wildebeest, zebra and gazelle, and past experience says that this would be sufficient to cause a massive shift in the whole ecosystem of the park.  That’s The War Against The Motorist right there.

Finally, your moment of zen: 11foot8.com

Helmets and seatbelts

From the World Health Organisation’s Multi-Sectoral Forum on Road Safety in China (March 2008), on driving in a country where over a quarter of a million die on the roads each year:

Both lack of awareness to risks and inexperience means that people all over the world, not just in China, are more likely to engage in dangerous behaviour such as speeding, driving without a seatbelt or a helmet, and drink driving. Without action, the road injury toll will only worsen, because it is a well know fact that basic road safety measures like seatbelts and helmets save lives. The more commonplace they become in China, the more lives will be saved on the roads.

I was shocked by the reckless behaviour of Beijing’s 5 million car drivers and their passengers: I did not see a single one of them wearing a helmet.  Were they to be involved in a collision, a helmet might mean the difference between life and death.

More interestingly, while seatbelts are compulsory in China, most Beijing taxis halve the cost of seatbelts by only installing one half of the belt per seat — either the belt or the socket is present; rarely both.  More interesting still is the curious and bizarre fact that a third of Beijing taxi drivers only pretend to wear their seatbelt.

The most shocking thing of all, though, is that Beijing has provided the visitor to the city with a fleet of convenient taxis — but where were the helmets for passengers to use?