Posted by: wesleyjohnston | January 1, 2013

2012 Road Deaths in Northern Ireland – Analysis

As has been noted in the media, 2012 saw a new record low for the number of people killed on our roads. Official statistics will likely show that 48 people died on our roads in the past year, compared to the previous record of 55 set in 2010. In 2011 59 people lost their lives.

In this blog post I’ll discuss the figures for 2012 both in isolation, and in their wider context. I should stress at the outset that these are not just statistics. Every person who dies on the roads is someone’s child and loved one, so nothing in this blog is intended to in any way trivialise the grief that has resulted from each of these deaths. I am interested in road deaths because I feel strongly about the need to make our roads safer.

Long-Term Trend

Headline: Road deaths are at a record low.

Although we must never be complacent about deaths on our roads, there is surely some space in these times of gloom for celebrating the continued fall in death rates. The previous record of 55, set in 2010, was astonishing given that it was less than half the figure who died the previous year (115). Around the Millennium the long-term trend was around 150 per year, and this showed no sign of going up or down. This situation began to change in the mid 2000s, when year-on-year falls began. In 2008, for example, 106 people died and even this was hailed as a remarkable achievement. When the figure of 55 arrived at the end of 2010 it was so low that statisticians cautioned, quite correctly, that we should not conclude too much from a single year.

After three years of figures in the same range, however, we can tentatively say that these much reduced figures seem to be a new norm. This does not mean that in future years the figure will always be lower than 48. Car crashes have a random distribution, so some years may be higher and some lower than this. But while we must not be content with 48 deaths, we should at least pause to reflect on the remarkable reductions that have been achieved over the past decade:

1 Road Deaths NI per year

Two years ago the Department of the Environment published the Northern Ireland Road Safety Strategy to 2020. This contained an ambitious target to reduce road deaths by at least 60% compared to the 2004-2008 average by the year 2020. The 2004-2008 average was 126 deaths. A reduction of 60% would be 50 deaths, so this target was actually met in 2012. With 7 years still to pass before 2020, we can therefore aim to achieve significantly more than a 60% reduction in that time frame.

How has this been achieved? A number of factors can be identified.

  1. Better cars. Car manufacturing has now reached a point where people are surviving crashes that would have killed them even ten years ago. Technology is also reducing the number of crashes themselves.
  2. Better roads. Roads Service are continuously improving the road network, improving sight-lines, adding crash barriers and dual-carriageway upgrades. During the past ten years a number of very dangerous roads have been upgraded to dual-carriageway. These include the A1 at Newry and the A4 west of Dungannon, both of which were previously seeing several fatalities per year.
  3. Effective campaigns against excessive speed. In 2002 excessive speed accounted for 43 deaths. This has since fallen dramatically, and in 2011 only accounted for 7 deaths. Thanks to speed awareness campaigns, speed is no longer such a dominant factor in road deaths in Northern Ireland.
  4. Effective campaigns against drink/drug driving. In 2002 these were blamed for 28 deaths, but by 2011 this had fallen by more than two-thirds to 9 deaths.

We will now move on to a more detailed analysis of 2012. The PSNI release daily and annual figures for road deaths, but these were not precise enough to allow me to do the level of analysis that I wanted to. So in order to facilitate this analysis, I maintained a list of all road deaths that occurred in 2012. This information was based solely on news reports that are in the public realm.

I should say at this point that, although the official figure compiled by the PSNI (and hence the figure I am using) is 48 deaths, I counted a total of 49 deaths on the roads in 2012. The discrepancy seems to be this incident, which I counted but which does not seem to have been included in the PSNI’s statistics. Perhaps they did not count it because they are aware of facts that I am not – I don’t know.

Entire Population

The Northern Ireland Travel Survey, published in December 2012, gives details of the total distance travelled by the people of Northern Ireland per year. The most recent figures are for the period 2009-11 (it’s done as a 3 year rolling average). These figures show that, taking all modes of transport into account (including walking), people in Northern Ireland travelled a total of just under 17 billion kilometres on the road network in 2012. This gives us a useful baseline of 2.84 deaths per billion kilometres travelled on our roads. In other words, for every billion kilometres travelled on the road network by any mode of transport, there were 2.84 deaths during 2012.

By Gender

Headline: In 2012, males were more than twice as likely to be killed in a road crash than females.

2 Deaths by gender

The Northern Ireland Travel Survey shows that men travelled almost 30% more than women during 2012. But even taking this into account, males were killed at a rate of 3.93 for every billion kilometres they travelled, compared to 1.54 for females. Since we have already adjusted for the fact that men travel more, this suggests that men are inherently more likely to be killed than women. There could be a number of reasons for this such as: different driving styles between men and women; or perhaps men driving types of vehicle that have poorer safety records in Northern Ireland, such as motorcycles or bicycles. Nevertheless, it does suggest that when seeking to reduce road deaths further, measures targeted particularly at men would seem to be advisable.

By Gender and Age

Headline: In 2012, men over the age of 60 were the most likely to die in a road crash.

The Northern Ireland Travel Survey divides the population into four age brackets: children under 16, 16-29, 30-59 and 60+, and also by gender. This allows us to divide the population into eight demographic groups by age and gender and calculate the road death rate separately for each one. Since the travel survey lists how far the average person in each group travels, we can adjust the figures for the fact that the very young and very old travel less than those of middle age.

3 Deaths Age Gender

* In three cases the age of the victim was not released, so these three cases are not included in this graph. However all three were male. If added, they would tend to increase the death rate in the relevant age bracket.

Even taking this into account, the surprising result is that men over the age of 60 are the most likely to die in a road crash, suffering a death rate almost triple the average. The increasing frailty that comes with age means that the elderly are naturally more likely to suffer fatal injuries in crashes, and will therefore often be killed in accidents that a younger person would survive. We can therefore always expect the elderly to be over-represented in road deaths. However, this does not fully explain the result since women over the age of 60 are almost ten times less likely to die than their male counterparts, even though they travel almost the same distance on the roads (older women travel less than older men, but this is cancelled out by the fact that there are more older women than older men). So there must be other factors, independent of frailty, to account for the fact that men over the age of 60 are so over-represented in road deaths.

Many crashes on our roads are caused by two or more road users being involved in a collision, eg two cars or a car and a pedestrian. However, some crashes involve only one vehicle. In these circumstances, with nobody else involved and barring some factor outside their control, it very often it is an error by the driver of the vehicle that was the cause of the crash. What is noticeable is that being killed in an accident where no other vehicle was involved seems to become more likely with age. For 2012, the statistics are as follows:

  • 16-29 years old – 20% of deaths were cases where no other vehicle was involved
  • 30-59 years old – 31% of deaths were cases where no other vehicle was involved
  • 60+ years old – 50% of deaths were cases where no other vehicle was involved

It is not that politically correct to point this out, but in the interests of road safety we have to highlight that older road users are much more likely to be killed in a crash where nobody else was involved. As this is a percentage of all accidents in the age group, the fact that older people are more vulnerable in a crash cannot be the explanation. So again, this may reflect the effect that increased frailty has on the use of a vehicle.

The group that has the second highest death rate is young men in the age range 16-29, suffering a death rate almost double the average. What is also surprising is that young women are almost as likely to die as young men, but it has to be said that young women who were killed were much less likely to have been the driver (1 out of 6) than young men (5 out of 9) in 2012. This shows that (with the exception of older men) young drivers are more likely to be killed than older drivers.

All other age/gender groups have death rates below or far below average. This, thankfully, includes children despite the recent tragedy in Dundonald. It also includes women in all age groups other than 16-29. Women over the age of 30 are the least likely to be killed in a crash, with a death rate that is less than a third of the average.

All of this suggests that when seeking to reduce road deaths further, measures targeted particularly at older men and people aged 16-29 would seem to be advisable.

By Mode of Transport

Headline: Motorcyclists, cyclists and pedestrians are the most likely to die on the roads. Bus and car occupants are the least likely to die.

The Northern Ireland Travel Survey gives the total distance travelled by each mode of transport in Northern Ireland, so we can work out the death rate amongst users of each mode. The results are quite sobering:

4 Deaths by mode

It is fairly obvious that road users who have more metal around them (cars, lorries, buses) are less likely to be fatally injured in a crash than those with little (cyclists, motorcyclists) or none (pedestrians). However, it is sobering to note that in 2012 a motorcyclist was 50 times more likely to die on the roads than someone in a car, while cyclists were 15 times more likely to die.

Pedestrians are also 10 times more likely to die than someone in a car by this analysis. However, we have to be careful since this is skewed by the fact that pedestrians tend to be making short journeys, so the chances of being killed in a single journey on foot are almost certainly less than the chances of being killed in a single car journey. The same logic may apply to a lesser extent to cyclists. NI Greenways recently blogged about the worrying death and injury trends amongst local cyclists. By contrast, nobody died riding buses in 2012, making it statistically the safest mode of transport on the Northern Ireland road network.

The lesson seems to be that death rates amongst car and lorry users are now very low, but that when seeking to reduce road deaths further, measures targeting the most vulnerable road users – namely motorcyclists, cyclists and pedestrians – would seem to be prudent.

By Road Standard

Headline: Motorways and dual-carriageways remain our safest roads.

It is a long-recognised fact that motorways and dual-carriageways are the safest roads, and this is borne out once again by the statistics. Although a high percentage of accidents occur on main roads, this is because they carry much more traffic. By using data from the DRD (2009 Traffic and Travel Survey) and combining it with information from the Northern Ireland Travel Survey and my own lists of dual-carriageways in Northern Ireland, we can work out the amount of traffic using each type of road and hence calculate the death rate per billion kilometres travelled, which is a better way to assess the safety of a road for a given road user. The results are in line with expectations:

5 Death by standard*in 2012 there were 2 deaths on motorways. One of these was a man who fell from a bridge onto the M2 and was struck by a passing car. Over a longer time frame, the death rate for motorways in Northern Ireland is more typically around 0.8 per billion km travelled.

It is important to note that the roads with the highest speed limits are also the roads with the lowest death rates. This is because these roads have been engineered to a very high standard, and can thus justify their high speed limits. So when seeking to reduce road deaths further, measures targeting single-carriageway roads would seem to be most useful.

Other Implications

The success in reducing road deaths can be partially attributed to the work of Roads Service in improving the safety of the road network, especially in terms of junction improvements, visibility improvements, and road upgrades. However, perversely, it also hurts the case for further road upgrades. For example, between 2004 and 2009 the death rate on single-carriageway A-class roads was around 9 deaths per billion km travelled, compared to 0.8 for motorways and 4.2 for dual-carriageways. In 2012, however, the death rate on single-carriageway A-class roads had fallen to around 3 deaths per billion km travelled, which is actually less than the rate on dual-carriageways in 2004-2009. The dual-carriageway rate has, of course, also fallen to about 1.7. This means that the impact of a dual-carriageway upgrade on road deaths is not as significant today as it was even five years ago.

Of course, using this argument to say that road upgrades should not happen is totally back to front. Many of the reductions in road deaths have been the result of road upgrades, not independent of them. Deaths are still happening and can be reduced further by more upgrades. And deaths are not the only consideration – injuries can also be significantly reduced by dual-carriageway upgrades. And road safety is not the only argument for building dual-carriageways. Stopping dual-carriageway upgrades now because deaths are falling may be a bit like halting childhood immunisation because children are no longer dying from measles. We have to be careful not to miss cause-and-effect.

Where do we go from here?

Headline: Carelessness is the number one killer on our roads.

Last year I blogged in more detail about why people are still dying on our roads these days. In that blog I demonstrated that the principal cause of road deaths today is not drugs or speed or alcohol but carelessness, basically not adequately paying attention to what’s going on around.

Ten years ago excessive speed was a very significant factor in road deaths. Much of the attention amongst road safety campaigners at this point in time are therefore still in reducing vehicle speeds. But in moving froward from here we need to be careful that we do not focus too much attention on this one factor. If we are going to based our road safety strategy on facts, it is vital to stress that excessive speed is no longer a dominant factor in road deaths in Northern Ireland. The pie charts below show how the changes that have happened over the past ten years (source PSNI).

6a Causes of KSI 2002As you can see alcohol/drugs and excessive speed were the principal cause of 21% of road death/serious injuries in 2002, but only 12% in 2011. Campaigns against these factors are clearly working. However, carelessness remains the primary killer. As I said in my September blog post on the subject, carelessness covers a range of issues, but the primary killers are (a) inattention (b) crossing the road without looking (c) wrong lane and (d) inattention while turning in/out of a side road. Together these four factors are the cause of over a third of road deaths, triple the number caused by alcohol/drugs and excessive speed.

At this point in time, further efforts to reduce traffic speed have only a very limited potential to reduce deaths. Statistically speaking, if excessive speed was completely eliminated as a factor, the number of deaths in 2012 would only have fallen from 48 to 42. This is not to say that measures to reduce speed are pointless. Far from it. Six more lives saved is still six more lives saved, and the campaigns of the past ten years seem to have been demonstrably successful. Rather the point is that starting now, we need to avoid focusing too much on this single issue and instead give the greatest share of our attention to carelessness as the number one killer on our roads.

And, as the above analysis of 2012 has shown, particular attention also needs to be given to reducing the death rate amongst:

  • older men
  • young people aged 16-29
  • vulnerable road users – motorcyclists, cyclists and pedestrians
  • single-carriageway roads
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Responses

  1. I’m involved in safety campaigns and agree cyclists an people are the next to be looked at,People just randomly crossing roads unsafe should be fined aswell as
    Motorists

  2. […] to do with northern Irish road infrastructure and safety on his blog site. He has produced this excellent analysis tracking the history of road fatalities and the reasons for the welcome decline in recent years. […]

  3. […] Wesley Johnston is too polite to say it directly, but his excellent analysis confirms my suspicion. […]

  4. […] my 2012 analysis I offered some more detailed discussion about why this remarkable decline occurred between 2004 and […]


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