20mph speed limits and public health in Wales

In September 2023, Wales passed legislation making the maximum speed limit 20mph in built-up areas. How are speed limits linked to public health? How can researchers engage with governments to enact public health research? And how do you deal with the situation when there is a huge online backlash to your work? Dr. Sarah Jones from Public Health Wales joins Gavin to discuss how her research was implemented, how it's gone so far, and what's next.

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Transcript

This transcript was automatically generated using speech recognition technology and may differ from the original audio. In citing or otherwise referring to the contents of this podcast, please ensure that you are quoting the recorded audio rather than this transcript.

Gavin: Hello, welcome to The Lancet Voice. It's December 2024. I'm Gavin Cleaver, and we're really happy to have you with us today. We're going to have a conversation with Dr. Sarah Jones from Public Health Wales. Dr. Jones is an expert in road safety and public health and she's also one of the architects of the 20 mile an hour speed limit policy that was brought in Wales in September last year.

Dr. Jones joins us to discuss reducing road traffic injuries and the impact that has. But she also joins us to discuss the major populist backlash to the policy when it was implemented and how you go about dealing with something like that. We'll look into the journey of how the policy came to be, the challenges faced, and of course, its broader impact on public health.

I hope you enjoy this conversation between me and Dr. Sarah Jones.

Dr. Sarah Jones from Public Health Wales. Thank you so much for joining us here on the Lancet Voice today. It's a real pleasure to have you. I was at a talk you delivered a couple of weeks ago and I thought I have to have Dr. Jones on the podcast. The stories that she's telling are so fascinating and interesting.

I'm sure that our listeners are going to agree. As a little praise to you, for our listeners. You work in public health, but specifically in road safety and looking at road safety interventions that could help improve public health around Wales. That career specifically, how did you settle on that area?

Like, how did it come to, fascinate you so much? 

Sarah: Oh, it's an interesting one because my, actually I started off in sports science and I've always been. I was always, even when I was in sports science, I was interested not so much in elite performance, but in actually community level activity and participation.

Now at the time, I didn't know that was public health. I do now. And so that was where I started with community activity and then I moved on to a job in in Cardiff University looking at injury epidemiology, first of all in sports injuries and then in road traffic injuries and actually then the two are much closer than most people think because after all road traffic injuries dropped to very low levels.

And when I say road traffic injuries, really those involving pedestrians and specifically children. I dropped to a really low level some years ago, and this was an awful lot to do with the fact that children don't tend to walk or cycle many places anymore. So then you're going back to where I began, which is an interest in exercise science.

And actually for me, then it became a challenge of how we encourage people to walk and cycle without suffering the harms of road traffic injuries. As my career moved on into actually there's also harms associated with. air pollution with noise pollution, and how do we protect people from those while they walk and cycle, but also while they live near roads as well.

So it's actually much closer links than perhaps it looks at first at first glance. 

Gavin: So that's quite an interesting point, isn't it? Because I know obviously when you think about cars and the harms that they cause, you get the road traffic incidents, as you mentioned pollution and all that. But also, it's difficult to quantify the extent to which they stop people exercising.

Sarah: Yeah. It is. And we know from surveys that have been conducted over many years that time and time again, people say, I don't walk or cycle. I don't let my kids play out in the streets. I don't let my kids walk or cycle on their own because I'm fear, fearful of speed and traffic. And that's been the evidence base for years and years.

Yeah. Yeah. So for me then, I was thinking about how do we protect people from the harms that are associated with air quality, but also from speeding traffic so that Kids can play in the streets again. When I was growing up, we all played out in the street. Now, don't see anyone doing it.

And actually it's an important part of child development to be able to go out and socialise with other kids in the street. 

Gavin: Talking of speeding traffic, of course, you're one of the architects of a kind of major piece of public health policy in Wales, which Everyone in the UK has been familiar with it in the public health debate, but for our listeners further afield, the speed limit in Wales over the last year has been limited to 20 miles an hour in built up areas.

Tell us how kind of the idea for this policy first came about. 

Sarah: As I'm interested in road safety and my colleague Hugh who's a co author of the paper that we put together was very much focused on air pollution. And I, my PhD was in, in speed bumps in essence basically demonstrating that speed bumps could reduce road traffic injuries amongst children.

And for a time I thought, what a great piece of work this is because actually this is one of the few studies that we've been able to do that has demonstrated an activity, an intervention that has then gone on to narrow inequalities because the Child pedestrians in the most deprived areas are at many times greater risk of being involved in a road traffic incident than children in the least deprived areas.

And we demonstrated that if you put more speed bumps in the most deprived areas, then you can get a narrowing of those inequalities, which is great in one sense, but actually as my career went on, I realized the the enthusiasm of youth was perhaps somewhat misplaced. And the fact that, yes, it was great we could do this, but actually we also know that air pollution is more prevalent in most deprived areas too.

And actually by putting that traffic calming in, while we were stopping children being killed and injured in road traffic injuries, we were probably harming their air quality even more than it already was. And so actually then I started to think actually we need an intervention. That will address both of these.

Gavin: Sorry, so I was going to ask, how is it, for a very basic question, almost certainly, but how is it that speed bumps affect air quality? 

Sarah: Ah, because we generally pollute when we accelerate and we brake. So if you've got steady state driving, actually that's the least polluting part of driving.

What's most polluting is accelerating and braking. So if you put in lots of speed bumps, you get lots of acceleration and you get lots of braking. And if you think about it, we're burning fuel and we're we're putting brakes. So we're putting two pieces of metal together. It's not quite two pieces of metal together to try and slow down the speed we've created.

So yeah, in my enthusiasm for preventing road traffic injuries, I probably materially contributed to worsening air quality. So with Hugh, we started to think actually there's got to be something that's not going to harm air pollution and is going to improve or is going to reduce the chance of being involved.

In a road traffic crash and actually by looking through the evidence and looking for interventions, it seemed to me and looking more and more at more and more of the evidence that actually 20 miles an hour or a reduction in the default speed limits, 20 miles an hour could be one of the few, if any things that we had available to us that, that could bring about this magic target of.

Reducing the risk of road traffic injury and improving air quality. And so we did a little bit of of analysis, looked at some of the data. And when we did some, and I call it modeling in the loosest sense of the word, when we did some modeling we were able to show that yes the the likelihood was that 20 miles an hour reduction in the speed limit to 20 miles an hour.

Could have a beneficial effect on road traffic injuries and it would show no change in air pollution But of course over time if we go back to that notion of it being able to encourage more people to walk and cycle And we also know that the most polluting part of Driving is those short journeys when the engines cold If we can start taking a few of those out, because people can walk and cycle, then over time we are going to get big gains in air quality as well.

Gavin: You said of the things available to you, which I thought was a kind of interesting phrase, I guess that implies that you could have all of these sort of interesting public health interventions that could do some really radical things, but actually, in reality, when it comes to implementation, the band is quite narrow.

Sarah: Yeah, we can talk about a lot of things, I would also, for example, talk about significant improvements to public transport infrastructure, for example. But that's got to be done on a nationwide level and done in a way that everyone who uses those systems is able to access them in a safe, reliable, consistent manner.

Yeah. And the investment in public transport infrastructure is going to far outweigh the cost of changing signs to reduce the speed limit. 

Gavin: I guess on that front as well, ideation and coming up with a plan and modeling it and releasing the paper is all one thing. But then I guess you've got the quite high hurdle of convincing the kind of the politicians and lawmakers that this needs to be implemented and it's worth your while.

So how did that work for you? How did that process go? 

Sarah: I think it's fair to say that we were, so we were thinking about this at the same time as more powers were being devolved to Wales and the Draft Wales Bill, and I can never remember the year, I think it was 2017, the Draft Wales Bill proposed devolving power to set speed limits to Wales so it was one of those where you think, all right, but we can see this as a good idea, and look, and if you look over there, Actually, the legislative framework is consistent with this now actually being something that Wales has the legislative competence to do.

I rather suspect the intention at the time was that we would perhaps choose to increase speed limits on motorways, but it's, that was going on over there. And then on this side the wellbeing of future generations act demands that we the public sector in Wales doesn't take any action that is going to harm the environment for the future.

So we had a number of things going on and then plus we had a situation I think where there was perhaps already the inclination within some of the some politicians in Wales to start thinking about we might be being devolved power. What about if we dropped speeds rather than increased them.

So I think it was. It was perhaps almost a collective thought that this was not just an opportunity, but an option as well. There are other things that I've been involved in where Wales just doesn't have the power to, to act independently in making its own legislation. So you're almost at a We're just not sitting on our hands, but actually the levers are much more difficult to push whereas actually this one was we can see this public health benefit.

We've got Wales is if the power is being devolved to Wales and we've got a political class that looks like they are Angling towards wanting to do something that fits in with this as well. So if you like It was it was convenient and it was a lot of people thinking along the same lines at the same time.

Gavin: But you've got to have all those windows aligning at once, to get this stuff done. So how receptive were politicians when you like first brought it to them? 

Sarah: We actually, we went to the civil service first and we said, look, by the way, we're doing this bit of modeling.

And we Wales is a small place, so it's actually we're regularly in, in contact with officials in different departments of Welsh government. So I was regularly in contact with teams in the environment department and said to them, by the way you might want to know, we're doing this piece of work.

And they said, keep us in touch, tell us what's happening. So I think it was I know it was through them and they were able to work with their team. Through their networks within the within the civil service and start start to say, actually, this is what Public Health Wales, or this is what our colleagues in Public Health Wales are telling us they're doing.

Then we published a paper and actually, having a paper that, that you can say has been published in a in a a medical journal as Junior Journal of Epidemiology and Community Health that published this one for us. It's a really good lever because it was actually, we've had this paper published.

Our peers have reviewed it and said that, the methods are acceptable. The conclusions are rightly drawn from the results. And so actually people seem to think that actually what we've suggested is okay. And you can then pass that back into the civil service who can then distribute.

You and before you know it. It gives a certain sort of credibility, I think for the arguments that you're making. 

Gavin: The power of scientific publishing is something we love to discuss at the Lancet. So that's very good. That's very positive to hear. So when the policy was brought in September last year, there was quite a sort of almost populist led backlash to it.

So how how did you deal with that? Like how, how was it experiencing that? And then how did you subsequently deal with what was happening online and with politics and things? 

Sarah: It wasn't pleasant. I think the challenge was, I was also, once, once we'd put together the paper and once it became the political direction a, an implementation group was set up, a task force, if you like, to work out how the legislation should be introduced.

And the, there was a phenomenal amount of work went into this, but of course, in the meantime, COVID happened. And I think COVID was. a big influence on all of this, not just because, not least because it affected the amount of money that's available within government. Covid cost the UK government a phenomenal amount of money, cost the Welsh government a phenomenal amount of money, and we can't get away from that.

So I think then you look, you've got a government that's looking at we've got no money. So maybe when it comes to, to being able to spend money on communications and so on, you're thinking we don't have that. And I think it was a real shame. Because it meant that perhaps a lot of the work around communicating why we're doing something became a real challenge, because of course, COVID has detracted from money that you would have been able to invest in that.

And I think then the other side of that is that COVID um, influenced public trust in science, public trust in the medical profession, public trust in public health. And I think it, whereas before COVID, I think we would have been able to take a more relaxed, if you like, approach to talking about the evidence.

We'd have been able to say that there is a logical path from here to there. What we had was a much greater demand for actually, we need to know the exact numbers. We need to know how many people are going to be prevented from being involved in a crash. And if we can't talk about the exact number of people that are going to see improved air quality, then that, that's really difficult to sell.

And I think that's become a real challenge. So it meant that those conversations weren't necessarily possible, and I think people were generally less comfortable with the idea of Earth's government restrictions, because in effect, that's what we're talking about. And I think, we know you're, I don't think you're old enough to remember the seatbelts.

When seatbelts were introduced, and there was a backlash then. I can't remember it quite so well, because I wasn't very old myself at the time. But it happened then, the difference was we didn't have the same social media world that we would deal with now. And we don't have the same We didn't have the same scrutiny, and I'm not saying scrutiny is a bad thing, but I think COVID had left people with a real mistrust of science and whereas I would have once been able to say, I'm a professional, I've read the evidence and I've been through all of the evidence and I'm talking about this because I believe it really is the best for public health.

People were challenged that with Oh, I've seen something somewhere that said this, or I believe that. And there, I believe, was being held as an equivalent. weight to my I've read the evidence and I can, assure you of this. 

Gavin: That must've been very difficult for you to deal with the sort of weight of online opinion because it became such a political football.

But it's interesting, isn't it generally how much sway the car lobby has with that sort of thing? Because, I live right in central London and the amount of online anger and the sound and noise created by people upset about low traffic neighborhoods, for example, around here versus actually how many locals enjoy them and want more of them implemented.

I always find the whole thing quite there's an extremely noisy minority and then a very quiet majority who are actually like, Oh, actually, no, this is quite nice. 

Sarah: And I think this is what's really important is. We've forgotten how to listen to those who aren't shouting. And I always hark back, and I hope you'll hope you'll bear with me in this analogy a moment.

When I was back in, back at the beginning of time, when I was in university throughout my university years, I I lifeguarded. And one of the things that, that you taught as a lifeguard is, If there's two people that need help and one's making a lot of noise, that's the one that's just fine.

Because after all, if they've got enough energy to make a lot of noise, they don't need rescuing. The person who's not making a lot of noise, that's the one that you've really got to fight for. It's something that I've thought about regularly in my public health career, is that actually our job is to advocate for the ones that need rescuing.

Or that don't know that they need rescuing, or that just aren't able to make a noise. Because after all, fundamentally, that's what our role is in public health is advocates, advocating for those who aren't able to advocate for themselves. People who are shouting are doing alright on their own. And I think it's also it's also important to remember that while there was an awful lot of signatures on that petition, and there were, It was still only around 20 percent of the Welsh population.

That meant 80 percent of the Welsh population hadn't signed the petition. 

Gavin: And of course, signing it, of course, wasn't restricted to people, only people in Wales signing the petition, was it? 

Sarah: And that's another part of this argument. Actually, it was signed by people that had the time to go and sign it.

There's plenty of people that We're just getting on with life and enjoying the fact that Twenty was actually not the end of the world that maybe some would suggest it would be. And I think it's, I think it, it was really, it was unfortunate that it became a political football that it did because actually It is about doing the right thing for everybody in society.

Gavin: It's probably especially quite difficult in Wales as well, because I know from having lived there for many years, that generally once you leave the major cities, the public transport links are not great. Driving is something that I think people in Wales probably experience a lot more. 

Sarah: Yeah, I think you're right.

So I think, and, A lot of people were concerned that it would make a massive impact on journey times and journey times was something we'd looked at an awful lot. And actually we were, um, the evidence was suggesting, I think one, one thing, one thing I read was there was a suggestion of a delay of 17 seconds over a kilometer or something like that, and I was also part of a conversation in Edinburgh where they've done a similar sort of thing and the bus drivers there were saying, yeah, it's not the, it's not the speed limit changes that delay the buses. It's traffic congestion. It, this it's traffic lights. It's actually people getting on and off the bus and the time that takes.

So there were lots of, there were lots of concerns that perhaps weren't, we weren't able to rip that because the moon's just got so out of control and of course the way In which social media algorithms work as well means that if you try and refute some of these arguments, all you end up doing is amplifying the argument rather than the sword to the counter.

So it's actually, it's really difficult to know what to do for the best in a social media environment as well. 

Gavin: It's a really difficult comms situation, isn't it? And I suppose you were probably quite surprised by the kind of level of the backlash as well. Yeah. 

Sarah: I think so. I think we were all surprised by how bad it was.

It's difficult to say we weren't. I was also dealing with some issues personally as well that perhaps in hindsight were a good thing because it meant that I wasn't able to get quite so bogged down in the In the Ferrari as perhaps I would have done otherwise, but I think it, it was difficult not to be difficult to detach yourself and difficult not to take things personally, given some of the commentary, because actually it wasn't done.

It wasn't done on a whim. It wasn't done on a, trying to make things terrible for people. Actually, this was about trying to make better communities and to improve public health. Not some of the arguments that were made about how dreadful this would be. It was actually, no, this is about making Wales a nicer place to live.

Gavin: Has there been any early data so far? I know it's still early doors in data collecting terms. 

Sarah: So yeah, and I think this is also one of the challenges is that this type of thing doesn't bring results in, in the short term. And I think for me, it's really going to be a it's sort of 10, 15 years time that we're going to be able to look back and say, was that the right thing to do?

And I believe in that time it will be. But even in the short term, we're seeing big gains in, or big reductions, I should say, big reductions in road traffic casualties. We're looking at between 20 and 30 percent reductions in road traffic casualties. The lowest numbers of road traffic casualties at any point COVID years.

Which is, if you just take that, Gain alone, for me, that's huge. We know from department of transport estimates that a road traffic fatality costs somewhere in the region of 2. 2 million to society and the economy. And I don't like thinking about road traffic fatalities in those terms but unfortunately that's a government way of doing it.

But 2. 2 million that we're saving society and the economy. A person that doesn't have a family, whose lives are changed forever because they've lost somebody unnecessarily. A police officer that doesn't have to stand on a family's doorstep and tell them about the loss of a loved one. Fire and Rescue Service that don't have to deal with The aftermath of a crash.

Highways team that don't have to deal with the aftermath of a crash. Now, all of those things involve people that actually didn't have to do something horrific that none of us would want to have to do. An A& E department perhaps that didn't have to receive the casualty and try and fight for their life.

Not to have to do any of those things just once for me is a huge gain. And then in the longer term, if we've got parents that feel more able to walk with their kids to school or even let their kids walk to school on their own again, then actually we're doing the right thing for public health. So yes, the early signs are really positive and fingers crossed we continue along that path.

Gavin: That's great, isn't it? And you mentioned the kind of monetary value puts on a death, but it's interesting to me as well, how much discussion of road traffic accidents takes place purely in deaths. Whereas actually there's this huge, there's this Huge toll of injury as well, right?

All the way from just, in inverted commas, a broken arm, all the way up to serious injuries that require rehabilitation, that take people out of the economy, so that must be a, that's a huge gain as well. 

Sarah: It is, and I think what you've always got to be aware with road traffic injuries is that they disproportionately affect the young.

If we're talking about deaths, That's the death of a young person. So that's a whole life in many ways that there's a whole adult life that goes unlived. All of that potential that goes unfulfilled. But yeah, the effect of a young person being killed or injured on our roads, or even an older person, road traffic injuries are generally so awful that they're not A get up and walk away from with a few cuts and bruises. They require lots of healthcare systems to be supporting that individual for a long period of time. For me, and I'm geeky about this, so I'll hold my hands up, but what for me is so fascinating about 20 is that it doesn't just reduce the risk of the injury occurring, it reduces the chance of that injury being more severe.

So it's taken, It's challenging the threat of road traffic injuries from two perspectives because it's reducing the absolute risk as well as then the likelihood of more severe injuries occurring. So yeah, you're quite right. Counting things in deaths only is a poor way of doing it.

But there's also this this side of it, which is actually even when injuries do occur, they're likely to be less severe anyway. We're actually getting into the sort of territory where we could be looking at people picking themselves up and brushing themselves off and walking away rather than, Requiring the full extent of the health service having to be deployed.

Gavin: Hopefully with some stern words for the driver, at least, if they are getting up and walking away. But I wanted to ask you what you're working on now. What are the kind of next steps for your work in road safety in Wales? 

Sarah: I'd love to be able to say I spent all my time working on road safety. It's a bit of an aside, really.

I've got an interest in transport as a wider determinant of health. But I also I've been talking for I think I'm into year 16 or 17 talking about young driver safety. And this is something that is is reserved to Westminster. So Wales doesn't have power to make legislation around young driver safety.

And in the 16 years that I've been looking at this, the evidence is very clear on this, that, that graduated driver licensing reduces young driver crashes, casualties and fatalities. And when I say young driver, what I really mean is The crashes, casualties and fatalities of everybody associated with young driver crashes.

Young drivers are at very high risk of crashing in the first six months after passing their test. And actually graduated driver licensing can protect them, can reduce that risk. Efforts there are with just as with 20 miles an hour, there's an awful lot of other people involved.

I'm, I've just got the privilege of being one of those, but it's something that, that the evidence suggests can reduce road traffic deaths, injuries, and and crashes. 

Gavin: So when we say graduated, that's slowly giving them the privileges associated with a full driving license, right? 

Sarah: That's exactly what it is.

So the notion is instead of, as we do in the UK currently, you have a learner's license once you pass your driving test, you move straight to a full license. In countries such as Australia, New Zealand, in the U S and in, in other parts of the world, there's an intermediate phase put between the learner and the full license phase.

And in that intermediate phase young drivers and sometimes it extends to older new drivers as well. In the for the most part, it's new young drivers. They're given permission to drive unaccompanied. But not at night not with their friends, in essence, in the car. And when I say at night these restrictions usually start from around about 10 or 11 o'clock at night and go through until about 5 or 6 in the morning.

Those, the highest, that's the highest risk time for new young drivers. Along with driving with a group of their friends in the car. 

Gavin: Excellent. I suppose probably the government in Westminster at this point is probably a little bit more receptive, at least to measures like that. 

Sarah: I think, with a change, recent change in government we've got to wait and see what happens and whether there is whereas whether there is a willingness to think about this, there's been lots of conversations over the years.

And obviously always legitimate concerns about about restrictions and what these might do for young drivers, but actually I think if we look around the world, we can see that none of these concerns are insurmountable. And that there are ways to deal with the concerns that people have about the ways that this would work.

Gavin: Dr. Sarah Jones, thank you so much for coming on the podcast and telling us the fascinating story behind this policy and best of luck with your future work. 

Sarah: Thank you ever so much.

Gavin: Thanks so much for listening to this episode of The Lancet Voice. If you're interested in listening to more Lancet podcasts, you can go to thelancet. com slash multimedia, where you'll find not only all of our podcasts, but also our infographics and videos. Remember, you can subscribe to The Lancet Voice wherever you usually get your podcasts, and hopefully we'll see you back here next time.

Thanks for listening.