evidence-based policy – At War With The Motorist

Repost: Pickles peddles pointless parking press release

Not having anything new to post, but having been reminded of this antique scrawl by last week’s Cycling Embassy response to the Department for Communities and Local Government’s consultation on whether they should interfere in local parking policies, I figured I could fob you off with something originally posted way back in august 2011.

This week, the Department for Communities and Local Government put out a press release about town centre parking. Unlike last time, they didn’t even have to announce that Pickles is ending The War On The Motorist™. On that point, their work was done for them, by 36 newspapers and the Daily Express. Aren’t they well trained?

This time around, Rubberknickers Pickles is ending The War by lifting restrictions on how much of our town centres can be given over to car parking. The idea is nothing new, of course, but it is assumed that most will have forgotten the previous occasions when it was announced. The “news” is that the paperwork has gone through: the new version of the government’s planning rules are complete.

As far as I can tell, the notorious limits on car parking provision that have been dropped were Policy EC8, “Car parking for non-residential development,” in the Planning Policy Statement 4 of 2001 [PDF]. This policy instructs local authorities:

Local planning authorities should, through their local development frameworks, set maximum parking standards for non-residential development in their area, ensuring alignment with the policies in the relevant local transport plan and, where relevant, the regional strategy.

In determining what their maximum should be, the policy suggested that authorities think about the needs of non-car users, the effects of congestion and need to tackle carbon emissions and air pollution, and:

h. the need to make provision for adequate levels of good quality secure parking in town centres to encourage investment and maintain their vitality and viability

j. the need to provide for appropriate disabled parking and access

k. the needs of different business sizes and types and major employers

That is, the notorious Labour control-freakery over town centre parking was, er, an instruction for local authorities to develop guidelines that they think are suitable for their own local situations. The Policy document goes on to state that these local standards that authorities have developed should then be applied to planning applications — unless the planning applicant gives a good reason for them not to apply.

So these maximum limits are locally decided and not really binding. That doesn’t quite look like “centrally controlled parking quotas” to me. In his press release, Pickles says:

The Government believes councils and communities are best placed to set parking policies that are right for their area and based on local need – not Whitehall. Local people know the level of parking that is sustainable for their town centre.

Which seems to be exactly what the old Policy document supported.

Perhaps there was some other Labour policy, rule, or law that I haven’t been able to find? Anybody?

I’m not sure what real difference the removal of this policy makes. Previously councils were made to think about the effect of congestion and pollution and the like on their town centres, and the needs of people on foot and bike and bus. When a planning application came in they would know how to recognise whether it would be bad for their town, and they would have a good pre-prepared excuse to reject a development that would make their town centre a more congested and polluted place, or which would hinder walking, cycling, and public transport. But I assume that they’re still allowed to reject those developments if they still don’t like congestion and pollution and dead places?

But perhaps the new policy document will send a message to local authorities: your town centres are in a bad way, and you need to do something about it. In his press release, Pickles says that the removal of this rule will “provide a big boost to struggling high streets”:

The new draft National Planning Policy Framework, recently published, will do away with these anti-car restrictions introduced in 2001 and give high streets a boost to compete for shoppers. It will encourage new investment in town centres, provide more jobs and encourage more charging spaces for electric cars.

Unfortunately, Pickles doesn’t explain how the new Policy will translate into more competitive town centres with more jobs. More importantly, he presents no evidence to support the statement. So I went looking for it. Luckily, Greg Marsden has already reviewed the evidence on parking policies.

One of the studies that Marsden reviews is the 2002 Lockwood Survey, which divides “town centres” by size of the town/catchment area, and whose summary states:

4. Findings of the parking survey:

Major District Centres: Poor store performance is linked with low levels of parking, reliance on car parks more than 5 minutes walk from prime shopping streets and high charges (the report gives indicative levels).

Sub Regional Centres: Poor store performance is linked with reliance on car parks more than 5 minutes walk from prime shopping streets and high charges (the report gives indicative levels).

Regional Centres: Poor store performance is linked with high charges for 3 and 4 hour stays (the report gives indicative levels).

But when Marsden looked at the data he found it a lot more difficult to support these conclusions. In “major district centres”, those with very low levels of parking were indeed more likely to be performing badly. But those with mildly low levels of parking did better than those with high levels. And in regional centres, those with higher levels of parking were struggling more than those with lower levels. But those with very high levels of parking did a little better than those with very low levels.

There simply doesn’t seem to be any pattern in this data at all. The authors of the original report had cherry picked those parts of the data that made it look like low parking provision was harming shops, while ignoring those parts that said the reverse. Marsden found the same for parking charges and the proportion of parking spaces within a five minute walk of the main shopping area: the data was all over the place, showing no obvious and consistent relationship with economic performance. Why not? Because if variation in parking provision has any effect on town centre attractiveness and competitiveness at all, it is masked by far more important factors — perhaps factors like whether the town centre is easy to get to, has shops people want to use, and is a nice place to be.

So why is Pickles press releasing his new policy as the saviour for struggling town centres? Why did most of the newspapers toe that line? We’ve developed a national myth that giving over more of our town centres to parking is good for the businesses in them.

Sustrans documented the nature of this myth by talking to traders and shoppers on Gloucester Road in Bristol. Bristol is relatively dense and affluent with above average cycling and car ownership rates and, even by British standards, appalling public transport. Gloucester Road doubles as a major artery with many bus routes and a neighbourhood centre lined with mostly independent shops. As Bristol Traffic documents, its bus and bike lanes are usually filled with parked cars.

IMAG0286 — Not Gloucester Road, but a near-by case study which might teach us some things about why town centres are in decline

Shopkeepers on Gloucester road estimated that more than two fifths of their customers came by car. In fact it was only just over a fifth. They greatly underestimated how many people walked, cycled, or took the bus. The shopkeepers were perhaps being big-headed, believing that their businesses were capable of attracting people from a wider catchment area, when in fact most customers lived within an easily walkable distance.

And the shopkeepers greatly overestimated the importance of drivers to their business in another way: while the people who walked were likely to stick around and visit several shops and businesses, the drivers typically pulled up, ran in to one shop, and got out of there as fast as they could. Perhaps that’s because often they couldn’t even be bothered to park up properly and instead stopped in the bike lanes outside their destination.

High street shopkeepers and business owners greatly overestimate the importance of drivers to their success. Why? Perhaps proprietors are more likely to be drivers themselves, and, as is so often the case with motorists, can’t get their heads around the fact that so many others aren’t? Perhaps their view of the street through the big shop window is dominated by the big metal boxes passing through? Perhaps they see the apparent success of the big soulless out-of-town supermarkets and shopping malls, attribute that success to the acres of car parking, and leap to the conclusion that car parking is all that a business needs for success — that the model which succeeds on the periphery can be applied to the model that is failing in the centre.

I suspect that the opposite might be true. Those who are attached to their cars will go to the barns on the ring-roads. You won’t attract them back to the town centres. But by trying — by providing for the car parking at the expense of bike paths and bus lanes and wider pavements — you might drive away the surprisingly high proportion of town centre customers who don’t come by car, who come precisely because, unlike the malls, the town centre is walkable and cycleable and because the bus can get through. Town centres aren’t just competing with out-of-town malls and supermarkets any more. Those who don’t want to drive to out-of-town barns can sit at home, click on some buttons, and have things driven to them. Compared to most of the traffic-choked high streets in this country, that’s quite an attractive option.

A simple question

I like Select Committees. They do a good line in scrutiny, as we’ve seen lately with the Media Select Committee’s hacking enquiry. On tuesday the Transport Select Committee sat to look at road safety, calling a representative of the Association of British Nutters as a witness.

The ABD made some assertions and MPs responded with the simple question: how do you know that’s true? You can see the delightful outcome at As Easy As Riding a Bike, with further comment at MCRcycling.

It reminded me of an exchange with The ABD on twitter — perhaps the event which first got the thin skinned ABD blocking its detractors on twitter. Back in July, the ABD tweeted something about average speed cameras on the extremely expensive new section of the A3 at Hindhead. @highburyonfoot, @jamesgleave1, and I briefly exchanged tweets speculating about why this Motoring organisation should object to average speed cameras. They said:

@TheABD Assn of Brit Drivers
@highburyonfoot @steinsky @jamesgleave1 Av Spd Cams encourage anal attitude to speed limit rather than attentive driving.
16 Jul Favorite Retweet Reply

There was some comment on this:

@jamesgleave1 James Gleave
@TheABD @highburyonfoot @steinsky in what way? Surely sticking to the speed limit is a part of attentive driving?
16 Jul Favorite Retweet Reply

@simon_bannister Simon Bannister
@TheABD @highburyonfoot @steinsky @jamesgleave1 Car drivers shld be a bit more anal IMO – self control, restraint, attention to detail etc..
16 Jul Favorite Retweet Reply

@highburyonfoot Caroline Russell
@steinsky (@jamesgleave1) @theabd have a v low opinion of drivers’ ability to judge speed, yet think cameras unnecessary as deterrent.
16 Jul Favorite Retweet Reply

johnstreetdales John Dales
I.e. @TheABD is for ‘drivers who THINK of (not for) themselves’ & ‘Attentive’ = above the law. Nice!
16 Jul Favorite Retweet Reply

The ABD were strangely silent on these questions. But I was interested in the far more basic issue: how do you know that’s true?

@steinsky Joe Dunckley
[citation needed] RT @TheABD: Av Spd Cams encourage anal attitude to speed limit rather than attentive driving.
16 Jul Favorite Reply

It turned out that this request for evidence was more difficult for the ABD to respond to than I had expected.

@highburyonfoot Caroline Russell
RT @steinsky: @TheABD [citation needed]. Where is the study that shows this? > perhaps @TheABD can circulate?
16 Jul Favorite Retweet Reply

@steinsky Joe Dunckley
two days down, still no evidence… RT @steinsky: [citation needed] RT @TheABD: Av Spd Cams encourage anal attitude to speed limit rather…
18 Jul Favorite Reply

@steinsky Joe Dunckley
Another day passes without evidence appearing… RT @steinsky: [citation needed] RT @TheABD: Av Spd Cams encourage anal attitude to speed…
19 Jul Favorite Reply

@steinsky Joe Dunckley
Oh gosh, is it really more than a week with no evidence already? RT @steinsky: [citation needed] RT @TheABD: Av Spd Cams encourage anal a…
24 Jul via web Favorite Reply

@steinsky Joe Dunckley
Oh, I wonder if @TheABD ever found that reference? RT @steinsky: [citation needed] RT @TheABD: Av Spd Cams encourage anal attitude to spe…
12 Sep via web Favorite Reply

They never did get back to us with their evidence for the claim that average speed cameras encourage inattentive driving. It’s almost as if it never existed…

Norman Baker defends evidence-defying policy

Norman Baker, our ever embarrassing Lib Dem Minister for The Bits Of Transport That The Government Doesn’t Care About and part-time conspiracy theorist, pops up in the HoL Sci & Tech Committee report on evidence-based behavioural change policy, defending the coalition’s approach:

Even where ministers are aware of relevant evidence, other factors may lead them to disregard it. This appears to have been the case with current alcohol pricing policy (see Box 3, page 21). Norman Baker MP, a Minister at the DfT, explained: “evidence is best used to inform policy … but not to drive it in an unreconstituted way”; the Government “have to make choices based not just on the evidence-base … but also on the political objectives of the Government at a particular time, and to ensure fairness across the country”. Other considerations might include immediate reaction to events, judgements about ethical acceptability, cost and cost-effectiveness. These considerations might justifiably affect the extent to which a policy is based on the available evidence.

What does “political objectives of the Government” even mean? It sounds awfully like “ideology”. What does “immediate reaction to events” mean? Sounds to me a bit like outlawing a recreational drug because a couple of people who coincidentally used it recently died, or locking a lot of people up for petty crimes because they happened in the context of a recent big news story.

Of course, cost, cost-effectiveness, ethical acceptability, and indeed general public acceptability must be taken into account. But those things are pieces of evidence like anything else. This stuff is all part of the evidence that evidence-based behavioural change policy needs to be based on.

As the report itself goes on to discuss, behavioural change policies will fail if the public does not understand the problem — or the magnitude of the problem — that the policy is trying to solve. The solution must be seen to be proportionate to the problem. Sometimes you need to prepare the public and make your case: a few years of “clunk-click” paved the way for seatbelt legislation. If an intervention is a really good one, it only needs to be on the border-line of public acceptability to work and to very quickly become accepted: opposition to the ban on smoking in public places quickly disappeared, and it takes effort to find people opposed to the congestion charge these days.

Equally relevant is the fact that the public acceptability of interventions depends on their success. Design an intervention that doesn’t actually work — perhaps by ignoring the evidence — and you invite a backlash. The report cites the example of high alcohol prices in Scandinavia. This could perhaps help to explain the media’s obsession with The War On The Motorist: policies to tackle the problems of mass motoring might be unpopular if the number of vehicles on the road carries on growing regardless (even if the situation would have been even worse without those policies).

I don’t know. The formula might be complicated, but I can’t think of any part of it that should not be based on real world values. Can anybody see a favourable interpretation of Baker’s words?

Nudge nudge, do you follow me?

Call me a stereotype of the scientist buried in his own irrelevant little world, but it occurred to me that I know far more about how to manipulate the behaviour of transformed cell lines than that of people. The War On The Motorist™ was, of course, part of the great evil Labour project to change some of our more anti-social and self-destructive behaviours. So I thought I should probably find out about how these government-led behavioural change projects work.

There are, of course, all sorts of different ways that governments can try to reduce destructive behaviour, from outlawing it to asking nicely, via making the bad options harder and making the good options easier:

(This table, incidentally, neatly describes where the chaps at Cycle Chat slipped up when claiming that the rise in domestic recycling rates demonstrates that we can achieve mass cycling without cycling facilities: mass domestic recycling required a change in the physical environment — kerbside recycling boxes — exactly equivalent to the changes to the physical environment that are required before we can expect most people to cycle.)

The current government has an ideological bias against some of these varieties of behavioural change, and in favour of others.* Regulation and taxation is, of course, off the agenda. Rather, the government says it wants to influence behaviour by making it easier for us to make the right choices. It will do this, it claims, without making the bad choices impossible or even more expensive, and without even requiring our conscious deliberation. In the fashionable pop-economics terminology, it’s going to “nudge” us in the right direction.

The pop-economics writers have some favourite examples of “nudges”. Changing the environment by putting the fruit bowl in plain view and easy reach, without banning the junk food option. Or reducing laundry loads by changing the hotel bathroom signs from “hang your towel on the rack if you are going to reuse it” to “most guests hang their towels up and reuse them”. The environment or the information nudges people into making the right choice, without actually taking choice from them.

It all sounds very nice, but I wonder what the evidence says about the government’s approach? Does it really work? Are they doing it right? And what does it mean for transport and The War On The Motorist?

Luckily, the House of Lords Sci & Tech select committee are ahead of me. I like select committees. So far as I can tell, their job is to closely and carefully scrutinise what the government is doing (or failing to do), point out when the evidence indicates that they’re messing things up, and then to be completely ignored by government, media, and the unfortunate oblivious electorate. The HoL Sci & Tech committee produced a report a couple of weeks ago looking at the present government’s approach to behaviour change programmes, and in particular, the extent to which they were informed by the evidence of what works and what is worthwhile. I’ve been scrolling through it and will probably dump a load of thoughts on the blog this week.

My initial concern was that, though it speaks of nudges and wanting to avoid limiting choice through regulation, it is not regulation that the government is really trying to avoid: it is spending money on doing a job properly. We’ll see if I’m at all reassured by the time I’ve finished digesting it and posting about it…

* Of course, the far end of the libertorian wing will object to any and all government-led behavioural change, but I will assume for now that we all understand why we need it, and why we need it done properly

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.

Pickles peddles pointless parking press release

Local planning authorities should, through their local development frameworks, set maximum parking standards for non-residential development in their area, ensuring alignment with the policies in the relevant local transport plan and, where relevant, the regional strategy.

h. the need to make provision for adequate levels of good quality secure parking in town centres to encourage investment and maintain their vitality and viability

j. the need to provide for appropriate disabled parking and access

k. the needs of different business sizes and types and major employers

So these maximum limits are locally decided and not really binding. That doesn’t quite look like “centrally controlled parking quotas” to me. In his press release, Pickles says:

The Government believes councils and communities are best placed to set parking policies that are right for their area and based on local need – not Whitehall. Local people know the level of parking that is sustainable for their town centre.

Which seems to be exactly what the old Policy document supported.

Perhaps there was some other Labour policy, rule, or law that I haven’t been able to find? Anybody?

The new draft National Planning Policy Framework, recently published, will do away with these anti-car restrictions introduced in 2001 and give high streets a boost to compete for shoppers. It will encourage new investment in town centres, provide more jobs and encourage more charging spaces for electric cars.

One of the studies that Marsden reviews is the 2002 Lockwood Survey, which divides “town centres” by size of the town/catchment area, and whose summary states:

4. Findings of the parking survey:

Major District Centres: Poor store performance is linked with low levels of parking, reliance on car parks more than 5 minutes walk from prime shopping streets and high charges (the report gives indicative levels).

Sub Regional Centres: Poor store performance is linked with reliance on car parks more than 5 minutes walk from prime shopping streets and high charges (the report gives indicative levels).

Regional Centres: Poor store performance is linked with high charges for 3 and 4 hour stays (the report gives indicative levels).

Smoothing the flow: pushing more kids into cars

We know that Boris Johnson’s fantasy of “smoothing traffic flow” will act as an incentive for people to get into their cars and, even more so, for businesses to move more stuff around. In a city like London there is much more potential demand for road space than could ever be supplied, because individuals and businesses who see an empty bit of road will always conjure some reason to fill it. An equilibrium is maintained by the tolerance that individuals have for sitting in traffic and the tolerance that businesses have for spending money doing business on the roads. Add or remove capacity to London’s road network and it will not make the slightest difference to congestion or journey times. It’s not like we haven’t tried it enough time to be sure of that.

What is not so obvious is that in addition to pulling people into motor vehicles, it will push them in too. There are several reasons why. One of them is that the mayor is ripping out traffic lights and pedestrian crossings, making walking more difficult, dangerous, and time consuming. There are a number of reasons why this will push people into cars, but I stumbled upon a nice one while skimming through Hume et al, Walking and cycling to school: predictors of increases among children and adolescents.

Hume et al looked at the variables that affected the success of a programme to encourage walking and cycling to school. They surveyed the opinions of the children and their parents on all sorts of aspects of their lifestyles and of their social and physical environments. Two variables were strongly associated with success: the perception that other children in the neighbourhood were walking to school*, and the provision of safe crossings.

Well, not exactly the provision of safe crossings, but the perceived provision of safe crossings. Specifically, the survey asked participants if they agree/disagree with the statements “there are no traffic lights / pedestrian crossings for my child to use” and “I am satisfied with the pedestrian crossings in my neighbourhood”. Parents, whose job it is to worry, are of course easily affected by perceptions of safety, and when they perceive safety to be compromised they do something about it — like put their child inside a big metal box.

Even if there is just about a sufficient provision of crossings to get their child to school, the provision of crossings in the wider neighbourhood will still affect whether a child is walked or driven to school for all sorts of reasons, including: the perception of how safe it is to walk to school is influenced by an environment wider than just the route to school; the number of other children in the neighbourhood walking to school will itself be influenced; and those living in less walkable neighbourhoods are more likely to own and frequently use cars, including over short distances, making driving to school seem like a less unusual thing to do.

Off course, none of this says anything certain about what the precise effects of the mayor’s removal of traffic lights and pedestrian crossings will be — quite the opposite. In the complex, chaotic, unstable and irrational world of travel choices, the mayor can’t hope to make isolated quick fix tweaks without sending unpredictable shocks through the system.

Further problems with the mayor’s traffic lights games are discussed by Cycle of Futility.

Won’t somebody please think of the children?

In December 2005, an article of massive importance was published in the British Medical Journal. Doctors counted up the number of children being admitted to A&E with musculoskeletal injuries (breaks and sprains — many of which would have been caused by bicycle-related incidents) on summer weekends and discovered a startling pattern. A new preventative intervention was discovered. They authors say:

The figure shows the weekend attendance to our emergency department in June and July between 2003 and 2005. The mean attendance rate for children aged 7-15 years during the control weekends was 67.4 (SD 10.4). For the two intervention weekends the attendance rates were 36 and 37 (mean 36.5, SD 0.7). This represents a significant decrease in attendances on the intervention weekends, as both are greater than two SD from the mean control attendance rate and an unpaired t test gives a t value of 14.2 (P < 0.0001). At no other point during the three year surveillance period was attendance that low. MetOffice data suggested no confounding effect of weather conditions.

From this data on the effect of Harry Potter books on injury rate it should be blindingly obvious that countless lives would be saved if legislation made Harry Potter books compulsory — for children at the very least (we can perhaps allow adults the freedom to choose to turn themselves into dribbling brain damaged wrecks by not reading Harry Potter).

Anybody who cycles while not reading Harry Potter clearly deserves to have their brains smeared across the road. They lack any credibility.

Gwilym, S. (2005). Harry Potter casts a spell on accident prone children. BMJ, 331:1505-1506 doi:10.1136/bmj.331.7531.1505

Further reading: ‘Tis the season, from Language Log.

Appendix: Bad Science Bingo in the BMA’s “safe cycling” pages

This is just a crude brain dump of a post that comes after the serious series — posts one, two, three, four, five, six, seven and eight.

Sorry, I just can’t get over these extraordinary pages on the BMA’s website. Here’s a very quick run through some of the Bad Science Bingo points that leaped out.

There were the canards, fallacies, and methods of misdirection:

Obviously there’s the emphasis on anecdotes and cases, the lowest form of evidence, which are essentially appeals to emotion.
Coupled with that the description of the “beliefs” of a few doctors, designed to nudge readers into conformity (acting as a subtle argument from authority for readers who are not doctors, and an argumentum ad populum for those who are).
Specifically in a couple of the anecdotes the selective recall of serious injuries in non-helmet wearers and minor injuries in helmet wearers (creating the illusion of control).
“Figures from New Zealand show that in 2006 there were 883 cyclists injured and nine killed. This corresponds to 20 people per 100,000 injured and 0.2 people per 100,000 killed. These figures are lower than those reported for 1994 when legislation was first introduced.” Fun factoids, but they don’t actually say anything about helmet efficacy. Lots of things changed between 1994 and 2006. (Post hoc, etc.) Perhaps there is evidence for NZ’s legislation improving safety but the 2006 crude injury statistics aren’t it.
Incidentally, while we’re on correlation and causation, the authors even get their statements on cycle tracks subtly wrong: “During the period of 1976 to 1995 Germany almost tripled their mass of cycle networks and this led to a 64 per cent drop in cyclist deaths.” While the evidence of a causative link is much stronger here, it’s a lot more complicated that a simple one “led to” the other. The reference does indeed state that Germany tripled their cycle network and that their death rate fell, but it notes that the later is in part the result — directly and indirectly — of the former.
I loved this statement, when discussing the side-effect of reduced rates of cycling: “If legislation were to reduce the rates of serious injury and promote increased public confidence in cycling, the effect might be to make cycling more popular. Clearly, there is a need for further research on this matter.” I don’t know where to begin. After dismissing all the side-effects of helmets as being based on too weak and preliminary evidence, the BMA counter it all with a speculation based on none at all — and tell us that there is a clear need for more research. Well quite.

And there were specific claims or activities that run counter to the cited evidence, or subtly misrepresented it (I did not systematically check references, these are simply things that leaped out as contradicting what I recall of the literature):

On page 2 the BMA list the things they are doing in addition to promoting helmets. The first item is “publicity and education campaigns in order to raise drivers’ awareness of more vulnerable road-users, including cyclists”. We know that these don’t really work.
The “risk compensation” section on the fifth page cites just one source, the Spanish study described on Monday, whose study design we know can not answer the question that they are asking it to answer.
“As noted in Table 2 the Macpherson and Spinks 2007 Cochrane review found no evidence to either support or counter the possibility that legislation may lead to negative societal and health impacts such as reductions in cycling participation.” You would probably read this and think, “studies have been done and they found no evidence for X.” It actually means, “the studies didn’t bother looking at X.”

And there were fun inconsistencies:

Kirsty’s story on page 5, “Doctors believe that had she not been wearing a cycle helmet at the time of her crash, she would have died,” and on page 6, “They have been shown to reduce the risk of head injury and its severity should it occur. This does not apply to fatal crashes but in such instances the force of impact is considered to be so significant that most protection would fail.”

The resource is just generally bizarre. It has a very weird set of focusses. On one page it gives a seemingly arbitrary selection of factoids from cyclist demographics (notably absent is any acknowledgement that “cycling” is not a single activity); on another it notes the diversity of cycle helmet standards — but fails to discuss any of the important consequences of this, such as how few helmets these days meet the stricter standards that applied in the past, back when most of the evidence on helmet efficacy was collected. In a table on the fifth page they mention that a study found no evidence of helmets causing or exacerbating rotational injuries — yet this is the only mention they make of the rotational injuries problem. Their inclusion and omission criteria appears to be completely random.

Anyway, enough of this. I don’t want to hog the game — your turn.

How did the BMA get bicycle helmets so wrong?

In 1958, the UK licensed a drug for treating morning sickness. It worked very well. The studies all showed that pregnant women suffering from morning sickness received much relief with the drug. Three years later it was withdrawn, but not before 2,000 babies were born with birth defects — 20,000 worldwide — three quarters of whom would die in infancy. The drug was, of course, thalidomide. It managed to get licensed because too many of the people studying it were focused on very specific aspects of its activity on the disease states that it was thought to treat, and too few were stepping back and looking at the big picture. It prevented morning sickness, therefore it worked — the logic of the day.

Joe’s anecdatum: In 2003, Joe, an 18 year old male, slipped on some wet stairs in a block of flats. His head fell eight feet onto the concrete floor. He was not wearing a bicycle helmet. He had a headache for the rest of the evening. He has never been diagnosed with any long-term ill-effects.

A disaster on the scale of Thalidomide can’t happen these days because the path to drug licensing forces researchers to comprehensively check all effects and outcomes of a new drug. Individual researchers will know in extravagant detail very narrow aspects of how a new drug achieves its desired effect. Some of them will know the exact rate at which it crosses the various barriers into the blood and into organs; others will know the exact chain of activation of molecules and genes within cells, down the individual amino acid residues that are modified and the exact number of seconds after the drug is administered; others will know the exact schedule and mechanism by which the drug is broken down or expelled from the body. They’ll be really excited and enthusiastic about their new drug. But when somebody steps back and points out that the drug causes heart failure, it won’t get anywhere.

But the BMA seems to forget everything it knows about testing interventions when it comes to bicycle helmets. There are some superficial differences between helmets and what we normally think of as “medical intervention”. They are a physical intervention rather than a drug — but medicine deals with and properly tests physical interventions all the time. And it’s supposed to prevent rather than treat injuries — but medicine deals with and properly tests preventative measures, including conventional drugs, all the time. There is no intrinsic reason why bicycle helmets can not be tested properly, in line with the rules that were designed to prevent another thalidomide disaster. We have the methods and the expertise.

Joe’s anecdatum: In 2009, Joe, a 23 year old male, slid on the gravel on the Greenwich Peninsula Thames Path, hitting his head on the concrete path and writing off an £800 camera lens. He was not wearing a cycle helmet. He was unhappy and was bored for several hours waiting for Lewisham Hospital to glue his face back together. He stayed home all next day. He has never been diagnosed with any long-term effects.

And yet the evidence that we have on bicycle helmets is currently in a worse state than the evidence that got thalidomide licensed. There is some (limited) evidence that in people who have had crashes, helmets reduce the rate of specific types of head injury — just as there is undisputed evidence that thalidomide is effective in relieving morning sickness. But there is also (equally limited and disputed) evidence of several different side effects — an increase in other types of injury* and an increased rate of crashes (particularly crashes with vehicles, which are more likely to have negative outcomes). And there is also evidence that helmets discourage many people from cycling* — an activity that adds many quality years to people’s lives by preventing or delaying cardiovascular disease, cancers, diabetes, depression, dementia, and all those other diseases of sedentary lifestyles. Helmets might be an effective intervention for the types of injuries they are claimed to prevent, but that would be irrelevant if, like thalidomide, they cause more problems than they solve.

Joe’s anecdata: In 1991, Joe, a 6 year old male, on separate occasions smashed his head open a door, some concrete steps, and a glass coffee table. On no occasion was he wearing a cycle helmet. He has a scar on his forehead that is almost identical to James Murdoch’s. Unlike James Murdoch, he has never been diagnosed with any other long-term impairment or ill-effects.

I’m not saying that they do. The issue is not that there is overwhelming evidence against helmets. The evidence that they are the cause of crashes and other injuries is no stronger than the evidence that they prevent head injuries. The issue is that the evidence either way is nowhere near good enough to make a recommendation. If helmets were a drug, they would be nowhere close to getting licensed right now.

Which is why British doctors should be embarrassed that the British Medical Association currently lobbies for helmets to be compulsory when riding a bicycle. Imagine if a pharmaceutical company developed a drug which, if administered before receiving a specific kind of traumatic injury, makes that injury easier to treat. Imagine doctors and medical scientists lobbying for it to be compulsory for everybody to take this drug daily, without anybody ever having checked for side-effects.

How has this situation arisen? The policy decision has largely been made on the insistence of A&E consultants and trauma surgeons. Consider the anonymous quotations that are scattered through the BMA’s cycling pages:

‘I have seen – in my practice and when working in A/E – quite a number of serious head injuries from children falling off bicycles. I have also seen a number of children who wore helmets who only suffered minor injury. I am convinced that helmets reduce injury.’ — GP

’I would certainly support cycle helmet wearing for cyclists. I have seen far too many young lives ruined by head injuries.’ — Consultant in Emergency Medicine

’I am an Emergency Department Consultant and a keen cyclist. I wholly agree…that we need to move to an environment where cycle helmet wearing is the norm, rather than the exception’ — Emergency Department Consultant

’As a regular commuting cyclist through twelve miles of heavy London traffic and as a Consultant Emergency Physician I whole-heartedly support the BMA’s stance on the introduction of legislation to make the wearing of helmets mandatory.’ — Consultant and Honorary Senior Clinical Lecturer in Emergency Medicine

’Over the [last] 16 years I have worked in A/E. I have dealt with hundreds of head and facial injuries, particularly in children, that could have been avoided had a cycle helmet been worn. I have also had the misfortune to deal with a number of fatalities that I believe would have been avoided by simply wearing a helmet. I firmly believe that legislation making cycle helmet usage mandatory is essential.’ — Emergency Medicine Consultant and Clinical Director

‘I have worked in emergency medicine for the last twelve years. Personally I cycle around two and a half thousand miles each year and my family are rapidly becoming keen cyclists also. Prior to working in emergency medicine, I did not routinely wear a cycle helmet.

I have seen numerous examples of patients sustaining severe head injuries from which they will never recover whilst cycling at low speed without a helmet. I have never seen this pattern of pathology in cyclists wearing helmets under these circumstances.

I am aware of the recent Cochrane review on the subject. I firmly believe that all cyclists should wear helmets. I also believe that the only way to ensure this happens is through legislation. I can see no justification for allowing this entirety predictable pattern of head injuries to persist. I strongly support the BMA position…’ — Consultant in Emergency Medicine

That’s five emergency medics and a GP, all reciting anecdotes from A&E. Nobody who specialises in, say, public health.

Emergency medics and trauma surgeons are obviously very enthusiastic about the potential to put an end to injuries, just as people who were very focused on the problem of morning sickness were excited by thalidomide. But ironically, most doctors and scientists are not very good with complexity. They are good with the intense detail of their own specialism, but when they have a problem to solve they fail to consider that there might be relevant things happening outside of their own field. When emergency medics want to solve the problem of head and brain injury, they look at those injuries in isolation from the rest of medicine. It’s not their job to think about the bigger the picture, or worry about things like side-effects.

Indeed, dare I suggest that for most working emergency medics and GPs, the science of evidence-based medicine is not their job or even a major part of their training: they only need to practice what the scientists amongst them tell them to practice; most working doctors don’t need to understand how we know their interventions work.

Which is fine. But that stuff is somebody‘s job, and somebody isn’t doing it right at the BMA.

This way of thinking about the issue — as an isolated problem of emergency medicine — is reflected all through the BMA’s bizarre “safe cycling” pages, which emphasise these individual anecdotes and opinions of doctors in that field (despite “expert opinion” being frequently out of line with the science and despite everything we know about the ability of anecdotes to lead readers astray), while failing to ever think of the issues around helmets in terms of effects and side-effects or the usual path of research that is demanded for medical interventions.

The authors of the Cochrane review on bicycle helmets say, in dismissing risk compensation, “the fundamental issue is whether or not when bicycle riders crash and hit their heads they are benefited by wearing a helmet.” This is exactly analogous to saying that “the fundamental issue is whether or not when a pregnant woman has morning sickness her symptoms are relieved by thalidomide.” That is not the fundamental issue at all. The fundamental issue with any medical intervention is whether it does more help than harm, whether it improves the length and quality of our lives, whether we are better with it or without. That the authors of a Cochrane review are allowed to get away with saying otherwise is a great failure for evidence-based medicine. That the BMA think there is sufficient grounds not merely to promote this intervention but to enforce it is an epic failure.

* I thought about posting separately on these sets of side-effects too, but those posts would have been much like the rest of this series: there’s a plausible hypothesis, there’s some evidence to support it, but the evidence has limitations. Ultimately the conclusions always are: the evidence base is nowhere near good enough to support helmet promotion, let alone legislation.

The BMA, the BMJ, and bicycle helmet policy

The reason I pick up the bicycle helmet theme again this week is that the BMJ is running a sidebar poll of their readers (or, more accurately, of cycling tweeters and recipients of Robert Davis’s emails ;-)), asking whether it should be compulsory for adult cyclists to wear helmets.

The BMJ is the journal of the British Medical Association, the professional association and trade union of British doctors. Part of the BMA’s remit it to lobby the government on issues that its members believe are important, and it has some clout in this area. These policies are decided by a representative democracy — a group of members elected by region and by field. In recent years, this body has decided that it is BMA policy to support legislation that would make helmets compulsory for cyclists.

Doctors might not even have noticed the adoption of this policy. To most it is probably an irrelevance — most people will not cycle in the conditions that prevail in this country and doctors are no exception. And I imagine that very few have read the quite astonishing “promoting safe cycling” pages of the BMA website. Readers of Ben Goldacre should get their Bad Science Bingo cards out before clicking the link.

Tomorrow I’ll dissect those pages and ask how they came to be so bad. But there is a more basic issue here. Never mind whether helmets are effective or not, aren’t there more important policies that the BMA should be pursuing?

In 2002, the BMJ polled readers about issues of health and road danger — a slightly more scientific and insightful survey than the free-for-all yes/no question that they ask this week, and one much better targeted to British doctors rather than every joker on the internet. They asked readers to judge the importance, on a scale of 1 to 6, of various interventions for promoting the health and safety of pedestrians and cyclists. Helmets came out bottom of the doctors’ priority list:

Average ranking	Response
3.25	More and better cycle safety training
2.87	Compulsory cycle helmet wearing
3.42	Separate lanes for bicycles in urban areas
4.04	Traffic calming to reduce vehicle speeds in urban areas
4.04	Reduce car use by better public transport and by encouraging walking and cycling
3.85	Banning motorised vehicles from towns and cities

Interestingly, helmets for cyclists was ranked as only a slightly more sensible solution than helmets for pedestrians. Indeed, the results for pedestrians look much like the results for cyclists.

It’s the most heartening thing I’ve read in a long time. Most doctors get it. They’re not ignoring the bull. Certainly all of the public health doctors and epidemiologists (the people with the most exposure to scientific methods, incidentally) that I know get it. The problem is not that cyclists are taking insufficient measures to protect themselves from danger, it is that they are put in danger by motorists and by the government policies and societal norms that support the mixing of fast-moving motor vehicles, including those driven by people known to be dangerous and incompetent, with cyclists and pedestrians in our towns and cities.

Alongside their policy of lobbying for legislation to compel the use of helmets, the BMA has drawn up a set of recommendations for motor-vehicle reduction. But while the former policy is actively being pursued in Westminster and in the nations, the latter looks to have fallen by the wayside, and is still stuck in 1997. Why?

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:

They know it’s there.
They know it’s a safety feature.
There is a potential performance benefit to be had.
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.

Continue reading “Can drivers be taught a lesson?”

Second hand; unused

Thinking about how the Cycling Embassy might go about trying to generate political will to progress cycling, I’ve been researching previous failed attempts to advance cycling in this country. So on Amazon I snapped up a second-hand copy of an out-of-print British Medical Association book written in 1992: Cycling: towards health and safety.

People in Public Health are very interested in the bicycle because it keeps you fit — thus reducing incidence of obesity, cardiovascular disease, cancer, diabetes, dementia, depression, etc, etc — in a way that can be effortlessly integrated into everyday routines. And because it provides an alternative to transport modes that cause thousands of hideous traumatic deaths and injuries, even more air pollution-related deaths, isolation-related mental ill-health, and so on.

From a quick flick through, I’m expecting all that to be covered, in addition to a section on “barriers to cycling” which looks like it might cause a cardiovascular event itself by chatting about the weather while ignoring the elephant in the room.

But also when I quickly flicked through, I noticed I was breaking the spine. This second-hand book has never been read, never been opened except to stamp “date of cataloguing 14 May 1992” and “disposed of by authority” on the inside cover. Where does this never-before-read book make its way to me from?

Perhaps it’s for the best.