The risks of long distance running

This year’s London marathon saw the tragic death of Claire Squires. Subsequent media stories revealed that Claire’s was the eleventh such death since the event began in 1981. From this one can (in a sense) gauge the relative riskiness of marathon and long distance running as a sport. From 1981 until 2012 there have been about 850,000 competitors. Taking 4 hours as a rough race time means that competitors have collectively spent around 3.4 million hours on the course. A sometimes used risk statistic for comparative purposes is the death rate per 100 million hours of an activity, known as the FAR (Fatal Accident Rate). From this:

FAR for London marathon ≈ (100/3.4) x 11 ≈ 320 fatalities per 100 million hours

Budapest marathon 2011

How does this compare with other sports and other activities? Back in 1998 I made a study of fatal and non-fatal accident rates for a range of sports ranging from mountaineering to badminton (J. Sports, Exercise and Injury, 1998; 4:3-9). At that time the data showed the most dangerous sport was that categorised as ‘air sports’ which included aerobatics, gliding, hang-gliding, micro-lights, paragliding etc, and which had a FAR in the region of 200. Mountaineering was next highest coming in the range of 30-60, but has since been displaced into third place by caving which comes in at about 160. Water-related sports such as swimming, boating and fishing all have FARs of around 10 to 20, and horse riding comes in at 10. Sports such as rugby, soccer, hockey, cricket and badminton lie in or close to the range of 1 to 3.

From this (see histogram) it can be seen that marathon running is at the high risk end of the spectrum in terms of the FAR yardstick when compared with other sports. This is also true if compared even with industries operating in challenging environments, such as offshore oil and gas, where the FAR as reported by the International Association of Oil and Gas Producers is in the range of 5 to 10.

More generally, within the UK, occupational fatality rates can be estimated from HSE statistics. The average FAR for all workers is around 15, rising to around 70 in construction and 240 in agriculture. Likewise, Department for Transport statistics report FARs for various modes of travel: car 9.8; motorcycle 430; pedal cycle 38; pedestrian 15; bus or coach 0.63; rail 1.5.

So if marathon running is so risky why do it? The answer is that participation brings huge rewards in terms of physical fitness and health, psychological benefits, and social ones too. Even businesses benefit. But the debate over the relative merits and demerits of participation in these kinds of relatively extreme pursuits has been with us for thousands of years. When the London marathon was first proposed by Chris Brasher and John Disley in the 1970s there were objections, for example, that entrance should at least be restricted to club athletes. And during the earlier 1967 Boston marathon a race official attempted to physically eject Kathrine Switzer from the supposedly all-male event on the grounds that “Anything long like 800m, or even longer, God forbid, was considered dangerous ………” for women.

Times, and views, have clearly changed, and to some extent this has been unavoidable given the accumulating evidence of the health benefits of sport. Thus, in the nineteenth century, the view of Reverend Charles Wadsworth, with reference to the Oxford and Cambridge boat race, that ‘no man in a racing boat could expect to live to the age of thirty,’ was gradually proven wrong by epidemiological research which showed life expectation to be greater for rowers than non-rowers by several years.

For a concise and enthralling account of the history of beliefs surrounding the benefits or otherwise of physical activity, see Domhnall MacAuley’s ‘A history of physical activity, health and medicine’.

The debate, of course, continues. But it does illustrate the importance of collecting evidence and not being overly reliant upon subjective opinion and prior beliefs.

The Future of Risk Assessment?

Risk assessment is used to hugely-beneficial effect in many industries, ranging from off-shore oil and gas to nuclear and transportation. It is also used to plan for health epidemics, food safety and flooding. Generally the methods deployed are highly sophisticated, science-based and provide useful information for decision makers.

In recent years risk assessment has also been applied to public space and public activities, often using, by necessity, much simpler protocols such as HSE’s ‘Five steps to risk assessment’ (http://www.hse.gov.uk/pubns/indg163.pdf), or devices known as risk matrices of the type shown below which may range from 2×2 to even 10×10 cells.

These matrices, and the way they are used, are a source of worry for some eminent risk practitioners. For one thing they are usually qualitative in that there are no numerical values on either axis and both risk and consequence are subjectively-defined. What, for instance, does it mean to say something has a ‘medium’ likelihood? And in the case of public space is it the likelihood of something happening to one individual member of the public on a single visit, or on multiple visits over a year, or is it the likelihood that any member of the public might come to grief during, say, the next month? There are numerous possibilities but most matrices seem to leave this question unanswered despite having massive implications for their meaning.

Another technical anxiety is that users quite often number the cells along each axis from, say, one to three in the case of the matrix shown, and then multiply them together to generate a score for each cell. In this way the top right cell in the matrix shown would score 9, and the bottom left 1. This is troubling for several reasons. For one thing the axes are qualitative and labelling them from 1 to 3 produces ordinal numbers only (as in first, second, third etc), and not cardinal numbers. It never has made sense to multiply ordinal numbers together.

Another matter is that when numbers are multiplied, however ill-advisedly, they are sometimes said to be used as a means of prioritising and the aim of many risk assessors appears to be to shift hazards falling in the red-coloured boxes to the green ones. The requirement under the law, however, and which is deeply rational, is that control measures should be implemented if they are reasonably practicable. This is a much more sophisticated concept and is not replaceable by fiddling with coloured squares on grids. It could mean that hazards in higher-scoring boxes should not be subject to further control measures because there are none which are reasonably practicable.

An altogether different issue comes up when considering the risk assessment of public space and public activities, and this relates to the reason for their provision which is, obviously, their benefits. Public facilities, such as city squares, tree-lined streets, ponds and fountains, riverside walks, parks, playgrounds, forests, church yards, sites of cultural heritage, national parks, village fêtes, carnivals and sports of whatever kind produce benefits of all kinds ranging from health (physical, emotional and social) to intellectual stimulation, beauty and tranquillity. The problem is that these benefits get no mention in standard risk assessment protocols. It is as if the decision about whether, say, a public activity should be permitted or curtailed could be made purely by thinking about its inherent dangers and without any need to consider the benefits of the activity. This would be an irrational decision process. There is almost always some sort of trade-off between control measures and benefits when dealing with public places and public activities and it is essential that this be recognised, not ignored.

In effect, what has to be done is to weigh the benefits of, say, an unspoilt riverside walk and its risks, and make a decision on whether it should be left as it is or modified. This approach, of weighing risks and benefits, is what is increasingly being referred to as risk-benefit assessment (RBA). If you try to make this decision without thinking about either one of these commodities, the risks or the benefits, I for one could not conceive what was going on in the risk assessor’s head. But I suspect these for me unfathomable thought processes are quite common given that standard risk assessment protocols only refer to one side of this equation, leaving it open to ignore or forget the other.

Collectively these issues suggest that risk assessment as used in public life may require radical surgery.

Risk-benefit assessment

The move to get risk-benefit assessment recognised as a suitable and sufficient form of risk assessment is gathering momentum but still has hurdles to overcome. It seems that some agencies do not want to concede that the benefits of public space and activities should be a primary consideration in determining how safety from injury decisions should be made. This may be because this would result in a transfer of power because, to make balancing decisions, you would need to know about both the risks and the benefits of some place or activity and traditional H&S exponents may know little or nothing about benefits.

The case for RBA was strongly put in 2008 by Play England and the government in its ‘Managing risk in play provision – implementation guide’ (http://www.playengland.org.uk/resources/managing-risk-in-play-provision-implementation-guide.aspx). The case has more recently been expressed by the National Tree Safety Group in its ‘Common sense risk management of trees’ published by the Forestry Commission (http://www.forestry.gov.uk/pdf/FCMS024.pdf/$FILE/FCMS024.pdf), as well as by the long-standing Visitor Safety in the Countryside Group (http://vscg.co.uk/). Other organisations with strong interests include the Association of Heads of Outdoor Education Centres and the English Outdoor Council.

Overall, there is a widespread desire to get the benefits of public life back on the agenda of health and safety. Paradoxically, one of these benefits is health. But as the Trades Union Congress has put it, “Sadly we have a society that seems to see preventing injury as being more important than preventing illness.”