Last Thursday (21 March 2013) I attended a conference entitled Lies, Damned Lies and Statistics? Understanding casualty trends and the causes. It was sponsored by the Parliamentary Advisory Council for Transport Safety (PACTS). At the conference PACTS, the Department for Transport, and seven other organizations interested in promoting road safety launched a website called www.roadsafetyobservatory.com.
Its home page promises:
Key facts and summaries of research on road safety topics
The website proclaims:
“The Road Safety Observatory aims to provide easy access to independent road safety research and information for anyone working in road safety and for members of the public. It provides summaries and reviews of research on a wide range of road safety issues, along with links to original road safety research reports.
Its objective, the person presenting it made clear, was to provide an authoritatively fact-checked set of statistics to inform public discussion of road safety issues. Under the heading How is the Research Evidence Produced? it states:
The Programme Board commissions Research Reviews from a wide range of researchers and road safety experts. Each Review is then submitted to an independent Evidence Review Panel, who must approve it for publication on the Observatory website. The reviews are intended to be free from bias and independent of Government policies and the policies of the individual organisations on the Programme Board. They represent a summary of the best evidence readily available to the research community and will be kept under review as new evidence emerges.
I decided to subject this new source of evidence to my standard test. Into the Home Page search bar I typed seat belts do try it at home. This took me to “Road Safety Observatory Seat Belts Review, January 2013” bang up to date and approved by the Independent Evidence Review Panel. First up came “SEAT BELTS: KEY FACTS”.
Seven bullet points down I found this Key Fact: By January 2008, 25 years after the introduction of the law, front seat belts had saved over 60,000 lives in Great Britain.
On page 5 the claim is embellished: By January 2008, 25 years after the introduction of the law requiring car drivers and front seat passengers to wear seat belts (if fitted), it was estimated that front seat belts had saved over 60,000 lives in Great Britain.
On page 9 the claim is repeated twice.
And again on page 32: Seat belt laws increase seat belt use, and so reduce death and injury. 25 years after the first law requiring seat be to be used, it was estimated that front seat belts had saved over 60,000 lives in Great Britain.
The claim that the seat belt law saved 60,000 lives over 25 years is reiterated five times in a document approved by the Observatorys Independent Evidence Review Panel without any supporting citation I could find.
Citations are no longer needed. The claim has been repeated so often that it has become a fact that everyone knows. Typing seat belts 60,000 lives saved into Google yielded, at last clicking, over one million hits.
THE CLAIM IS OUTRAGEOUS NONSENSE. According to this claim the seat belt law is, by far, the most effective road safety measure ever implemented in Britain. 60,000 divided by 25 years would equal 2400 lives saved every year since 1983 by the seat belt law. In 1982, the year before the seat belt law came into effect there were only 2365 driver and front seat passenger fatalities! The claim is further, if less dramatically, contradicted by other claims in the same review indeed in the same initial bullet point: It was estimated that the seat belt law saved the lives of 241 drivers and 147 front passengers in 1983 and 270 drivers and 181 front passengers in 1984. The review does not provide a citation for the estimate of lives saved in 1983 and 1984 but they are similar to those provided in a June 2008 article in Significance by Richard Allsop, Oliver Carsten, Andrew Evans, and Robert Gifford (all members of PACTS). See table below.
Significantly the Significance article did not make it into the Reviews list of key references on seat belts. A significant omission because the authors, all defenders of the seat belt law, acknowledge an effect of the law of important consequence to vulnerable road users. They say the clear reduction in death and injury to car occupants is appreciably offset by extra deaths among pedestrians and cyclists.
This surely deserves a place in any list of Key Facts relating to the seat belt law.
Another Key Fact that did not make it into the review is the finding that almost all of the 1983 decrease in driver fatalities estimated by the authors of the Significance article took place between 10pm and 4am (the drink drive hours) and in drivers with alcohol in their blood. During the other hours of the day, and amongst alcohol-free drivers there was no detectable departure from trend (see Risk chapter 7). 1983 also happened to be the year in which evidential breath testing was introduced, and unprecedented numbers of breath tests were administered, and drink-drivers prosecuted. The modest claims (modest when compared to 2400) for lives saved in the table above can only be attributed to the seat belt law if one assumes that the measures introduced by the campaign against drink driving launched in the same year had no effect.
Who cares? Why does all this matter 30 years after the seat belt law came into effect? It matters because a new website sponsored by what might be called Britains road safety establishment, and promising unvarnished, unbiased, objective Key Facts, is telling a whopper. And not out of ignorance. The last time I looked PACTS, RoSPA and the DfT, key sponsors of the new website, all had the 60,000 claim still on their websites despite its absurdity having been called to their attention on a number of occasions.
The PACTS conference was well attended by people with a common interest in making roads safer. There was a detectable, and welcome, shift in emphasis from previous conferences I have attended from a focus on legal and engineering approaches to the problem, to an interest in changing attitudes and behaviour. As I have noted in Managing transport risks: what works? :
There are two different kinds of manager involved in the management of transport risks: there are the official, institutional, risk managers who strive incessantly to make the systems for which they are responsible safer, and there are the billions of individual fallible human users of the systems, each balancing the rewards of risk against the potential accident risks associated with their behaviour.
Understanding the attitudes of the latter to risk, and influencing their consequent behavior, represents the most important and challenging part of the institutional risk managers job.
Seat belts have acquired iconic status in common parlance. Fasten your seat belts is a phrase commonly invoked to introduce any exciting or threatening idea into a discussion. It is routinely used as a comparator for the postulated benefits of other forms of safety legislation such as cycle helmets. It reinforces legislator hubris look what we have achieved! they marvel as they pat themselves on the back. The Road Safety Observatory by virtue of its endorsement of the 60,000-lives-saved claim is further entrenching the iconic status of the seat belt law and energizing legislators keen to pass further well-meaning but misguided legislation.
To undo this damage PACTS, RoSPA and the DfT need not just quietly remove the claim from their websites, but prominently explain why. Likely to happen? Dont think so.
Recent posts and comments on this subject are on my website at http://www.john-adams.co.uk/category/seat-belts/