Is cycling a great way to get fit and save money on transport costs, or an increasingly dangerous pastime?

Cycling safety hit the headlines in November 2013 after a spate of cyclist deaths occurred in London over a two-week period and led to a range of claims and counter claims on safety. This Behind the Headlines special report looks at key topics on cycling safety and seeks to answer these and other questions:

Has cycling become more dangerous?

Are women more at risk of accidental death than men?

Are HGVs the biggest risk to cyclists?

Are there such things as cycle accident hotspots?

Can I lower my risk?

Is London a particularly dangerous place to cycle?

Do helmets improve cycling safety?

Do the benefits of cycling outweigh the risks?

Has cycling become more dangerous?

It depends what you mean by dangerous. The most authoritative data on cycling safety and accidents is provided by the Department for Transport (DfT). According to the latest figures, during 2012 in the UK:

118 cyclists were killed (one every three days)

3,222 were seriously injured (almost nine a day)

15,751 were slightly injured (43 a day)

These figures are based on incidents reported to the police, so the true figure for cyclists being slightly injured is likely to be much higher.

Serious injuries are defined as an injury resulting in prolonged hospitalisation and/or significant disability. The key measure used by experts to judge cycle safety is "killed or seriously injured", which is sometimes shortened to KSI.

Trends in cycling safety data

There has been a rise in the number of cyclists killed or seriously injured (KSIs) over the past few years. The DfT estimates that the number of KSIs in 2012 was 32% higher than the average recorded for the 2005-2009 period.

This rise in KSI incidents has to be matched against the increasing number of people choosing to cycle. However, it is difficult to accurately measure the rise in either cycling journeys or the time and distance travelled.

The National Travel Survey (NTS) of 2012 estimated an increase of around 23% in the number of cyclists, compared to the 2005-2009 period. However, this is just an educated guess. While it is relatively straightforward to estimate car ownership, based on official data such as car registrations and tax records, no such robust data exists for cyclists. Therefore, it is important to put the current risk of cyclists being involved in a KSI incident in context.

Official figures taken from the NTS suggest that the general risk of injury from cycling in the UK is just 1 injury per 19,230 hours of cycling.

It is possible that cycling has become more dangerous; however, the increased risk is thought to be small and should be seen in an appropriate context.

Are women more at risk of an accident?

Several newspaper reports have focused on deaths involving young female cyclists. These incidents are shocking, and may have led to a perception that female cyclists are more likely to be involved in a collision. In fact, men and boys are far more likely to be involved in a KSI incident than women and girls.

A 2009 analysis by the Transport Research Laboratory (a private research organisation) found that during the 2005-2007 period, 82% of KSIs were male.

A similar pattern can be seen in data published by the DfT and Transport for London (TfL).

While it is true that male cyclists significantly outnumber female cyclists in the UK, males are still over-represented in the KSI statistics. Even when taking this imbalance into account, it is estimated that males are 1.4 times more likely to be killed and 1.7 times more likely to be seriously injured than females.

Psychological research suggests that, generally, men take more risks than women. For example, a 2013 Dutch study found that male cyclists were less likely to have lights fitted to their bikes and more likely to run red lights at train crossings than female cyclists.

Women and HGVs

However, there is evidence that women in the UK have a greater risk of being involved in a collision with an HGV than men. The latest study into London's cycle hire scheme found that women were twice as likely to be involved in a fatal collision with an HGV, despite making up just 30% of the scheme’s participants.

One theory is that, somewhat counterintuitively, this increased danger is actually due to women being less willing to take risks.

A leaked TfL internal report suggests that women are less likely to jump red lights, meaning they are more likely to get caught in an HGV’s blind spot.

One UK researcher has argued that many women wrongly perceive that overtaking an HGV on the left-hand side is less risky, possibly because they believe sticking close to the curb is safer. The researcher did find a statistically significant trend in women reporting to be “left-side overtakers”.

Ideally, you shouldn't try overtaking an HGV (see Are HGVs the biggest risk to cyclists?), but if you do, it is safer to overtake on the right-hand side.

Overtaking an HGV on the left-hand side means you are in a driver’s blind spot for several seconds, and the vehicle could swerve suddenly into your path.

HGVs aside, female cyclists are actually less likely to be killed or injured in incidents. It would be easy to blame male risk-taking machismo, but the truth is we still don’t know why men are more at risk as cyclists.

Are HGVs the biggest risk to cyclists?

Riding aside these giant beasts of the road can be intimidating, but data suggests they are not as dangerous as other vehicles.

By far the biggest risk to a cyclist in terms of a collision are cars and taxis. The 2012 DfT report recorded 2,434 collisions between a cyclist and a car, with the KSI rate between a cyclist and an HGV just 114.

Unsurprisingly, however, cyclists involved in an HGV collision tended to sustain more serious injuries than those involving cars. In 2013, there were 14 reported fatalities in London, nine of which involved an HGV.

A surprising number of cyclists endanger themselves unnecessarily. In 2012, there were 248 KSIs with no other vehicles involved. Instead, cyclists were injured or killed for reasons such as falling off or hitting the kerb.

However, it’s worth highlighting that a significant number of these incidents occurred when cyclists were impaired by alcohol. Transport Research Laboratory estimated that around one in four “non-collision cycle accidents” was the result of drunk cycling.

The message for cyclists is clear: look out for vehicles of all types, but don't forget to watch out for yourself.

Are there cycling accident hotspots?

Yes; however, accident hotspots vary depending on the time of the day and the cyclist.

For example, during the working week, around 60% of cyclists killed are using urban roads. This trend is then entirely reversed during the weekend, with around 60% of cycling deaths occurring on rural roads.

Working-aged adults are most likely to be killed between the commuting time periods (6am to 9am and 3pm to 6pm), while retired adults are more likely to be killed between 9am and 5pm.

The latest figures from TfL show that most cyclist casualties in the capital were on A-roads, with the majority happening at “Give Way” T-junctions and at crossroads.

Cycling KSI incidents involving HGVs tend to follow a more fixed pattern. Most occur at junctions and roundabouts linked to major roads in urban environments. Speed limits do not seem to be a factor. A 2005 paper found that the majority of HGV collisions occur when the vehicle is travelling at less than 10 mph.

In summary, accident hotspots exist, but they are not necessarily at a fixed place and time.

Can I lower my risk?

To understand the contributory causes to fatal cycle accidents, the Transport Research Laboratory has analysed data from 2005 to 2007.

For cyclists, the most common factors associated with fatal collisions were:

Failure to look properly – 31%

Cyclists entering road from the pavement – 17% (children are particularly prone to these types of incidents)

Loss of control – 17%

Failure to judge other person’s path or speed – 15%

Poor turning or manoeuvring – 11%

Cyclist wearing dark clothes at night – 10%

Not displaying lights at night or in poor visibility – 5%

Disobeying road signs and markings – 5%

In motorists (both cars and goods vehicles) most common contributing factors associated with fatal collisions with cyclists were:

Failure to look properly – 44%

Passing too close to cyclist – 19%

Careless or reckless driving – 12%

Poor turning or manoeuvring – 11%

Failure to judge other person’s path or speed – 11%

Disobeying road signs and markings – 4%

On average, there were 1.82 contributory factors associated with cyclists involved in a fatal collision and 1.60 contributory factors for drivers.

This suggests that cyclists are slightly more to blame for fatal collisions. However, this is just one set of figures. Whatever the true extent of “blame” (if any can or should be laid), it is important to note that cyclists are likely to come off worse from a collision. Even the safest cyclist cannot avoid all possibility of an accident, and these figures would suggest that greater vigilance on the part of all road users would reduce the chances of a collision.

Is London a dangerous place to cycle?

London is not as safe as some other major cities, many of which are designed to be cycle-friendly. One such example is Amsterdam.

There are an estimated 15 cycling deaths a year in Amsterdam, which is slightly higher than the London average. However, more than half of all Amsterdam's residents cycle daily, so while the number is higher, the actual risk to individual cyclists on a journey is far lower than in London.

Compared to less cycle-friendly cities with similar populations, such as New York or Paris, cyclist deaths in London are similar, according to news reports.

There are reports that there were no cycling deaths in Paris over 2011. This is not the case. The zero figure corresponds to La Ville de Paris (central Paris, where HGVs have been banned at rush hour) – an area the equivalent in size to zones 1 and 2 in London's transport system. However, having no cycling deaths in such a densely populated urban area is an impressive feat.

Is London getting safer for cyclists?

Historical trends suggest that cycling in London has become safer. While it is true that KSIs have increased over the past few years, the number of people cycling has increased significantly, according to TfL data.

TfL figures show that the number of KSIs per year has remained relatively constant since 2000. At the same time, the amount of people cycling in the capital has risen by 150%. This would suggest that cycling has become a lot safer in London, compared to previous decades.

However, public perception (often driven by media reports) has a big role in influencing how safe a city feels to its residents.

There was particular concern during the end of 2013, when six fatalities in the city occurred over just two weeks (see Links to the headlines), with many commentators, cycling advocates and local politicians calling for urgent action.

Every death marks a personal tragedy for all those affected. However, in purely statistical terms, those two weeks could have been an example of what is known as “statistical clumping”.

Statistical clumping is when a number of low-probability events (such as fatal accidents) occur over a short period of time, purely by chance, and may not be indicative of a wider trend. Making news out of statistical clumps is a journalistic error.

Data suggests there were 14 deaths in 2013. This is the same figure as 2012 and lower than that seen in 2011 (when 16 deaths occurred).

However, as the deaths in 2012 and 2011 were more evenly distributed, not as much media comment was made.

There are steps that can be taken to make London (and other UK cities) more cycle-friendly. These include:

Creating more dedicated cycle lanes

Restricting speed limits to 20mph

Banning all HGVs from Central London during the day

Mandatory cycle training

Some cities have adopted similar measures. However, these steps would come with significant economic and political costs. There is the stock journalistic phrase: “You can’t put a price on a life”, but economists and politicians inevitably have to. It is a decision that health policy makers (such as NICE) have to make all the time, as spending on one aspect of healthcare reduces the ability to spend money on another.

Still there is a counter-argument that, long-term, making cities more cycle-friendly would save money.

The latest report (PDF 4.9MB) commissioned by the sporting body British Cycling, estimates that if one in 10 journeys was taken by bike, the NHS would save £250 million a year due to improved public health.

While London is not the safest place in the world to cycle, it’s certainly not the most dangerous, and appears to be safer than it was 10 or 20 years ago.

Do helmets improve cycling safety?

The majority of KSIs result in a head injury. One member of the Behind the Headlines team spoke to a DfT researcher, who said the issue of cycle helmets is the most contentious he has ever had to deal with – and he has still not reached a conclusion.

An editorial in the BMJ cited many instances when the use of cycle helmets increased (either through choice or by law); however, the actual number of KSIs remained unchanged or, in some cases, increased.

Reasons why cycle helmets may have little impact on overall KSIs include:

They may encourage the cyclist to undertake riskier behaviour

They may make motorists less considerate of the cyclist

Helmets may only be effective for minor injuries

Helmet wearers could be more risk adverse and therefore less likely to be involved in a KSI

There is also the possibility that making helmets legally compulsory could deter people from taking up cycling, and this could be counterproductive in terms of improving public health.

Due to such uncertainties, there is no legal compulsion to wear cycling helmets. More research needs to be done to reach firmer conclusions backing cycle helmets before such a law is passed.

The Highway Code states that you should wear a cycle helmet.

Do the benefits of cycling outweigh the risks?

A 2010 Dutch study attempted to answer this question, creating a sophisticated statistical model in which the potential benefits and risks of cycling were compared.

The benefits were described as being physical and associated with regular exercise, such as a reduced risk of diabetes, high blood pressure, heart attack, stroke and cancer.

The risks to cyclists were pinpointed as exposure to air pollution and the risk of having an accident.

The researchers concluded that the benefits of cycling far outweigh the potential risks.

They estimated that, on average, the benefits associated with regular cycling equated to up to 14 months extra life expectancy. The risks equated to a decreased life expectancy of up to 40 days; however, this was the upper limit and the figure may be closer to the 20-day mark. This represents an impressive benefit to risk ratio, despite only looking at the physical benefits of exercise. However, there are also documented psychological benefits of exercise, such as an improvement in mood, increased self-confidence and reduced risk of depression.

So it appears that, despite the risks, cycling is emphatically good for you.

Conclusion

While there is a great deal that could be done to make our roads safer for cyclists, the risks to your safety should not put you off taking up cycling.

It is cheap and convenient in terms of transport, and has numerous health benefits.

To reduce your risk of being involved in a serious accident:

Never cycle drunk and always pay attention to your road position and that of other road users

Wear appropriate clothing and make sure your bike is kitted out with lights. This ensures you are seen at all times of the day and night

If you are an inexperienced cyclist, practice in a park or a similar place of safety before venturing out on the roads

Read and learn the Highway Code – it applies to all road users, not just motorists

Get trained – those cycling proficiency classes you had back in school are probably not going to cut it for urban cycling

The DfT offers Bikeability training schemes – described as “cycling proficiency for the 21st century”!

Read more cycling tips for beginners and we hope you have many happy and safe cycle journeys.

Edited by NHS Choices