2012 May

CARRS-Q Research – Part Seven

A Country Where An Adult Is Treated As Such – Anywhere but Australia & New Zealand! (Photo: Dr P Martin)

Why you should dismiss the CARRS-Q bicycle helmet research

CARRS-Q’s Analysis of Police & Hospital Data

This is the final post in a series (Read Part OnePart TwoPart ThreePart FourPart Five, Part Six) looking at the non-peer reviewed CARRS-Q publication entitled “Bicycle Helmet Research“, published in 2011 and widely relied upon to support mandatory helmet laws for cyclists.  This publication was commissioned by the State Government to support its policy of mandatory helmet laws in Queensland, Australia, in the face of criticisms of its lack of support for Brisbane’s public bike hire scheme.

In addition to selective reliance pre-existing analyses of the efficacy of helmet wearing discussed in previous posts, CARRS-Q also sought to conduct its own analysis of data.  Data was sourced from police records and hospital data provided by the State Government’s Department of Transport and Main Roads.

The data was restricted to the years 1993-2008, and so cannot give any comparisons of injuries before and after mandatory helmet laws were introduced in Queensland in 1991.  The limitations to this data were recognised by CARRS-Q as follows:

“Reliable earlier data were not available and so all of the crash data analyses relate to after the helmet law and penalty were introduced.” (CARRS-Q, 2011, page 25)

“Research indicates there is significant underreporting of bicycle crashes … International figures suggest between 11% and 13%of bicycle crashes are reported in police statistics.  The reporting rates are even lower in Australia, with analysis of Western Australia data suggesting that only 3.5% are reported.  Actual reporting rates may be even lower, as these rates are calculated using hospital data.” (CARRS-Q, 2011, page 25)


“There are also suggestions that police-reported data will not only underestimate the magnitude of the cyclist injury problem, but it is likely to be skewed to serious injury crashes and those that involve motor vehicles.” (CARRS-Q, 2011, page 25)


“Within the hospital data, only the primary reason for hospitalisation is reported.” (CARRS-Q, 2011, page 25)


“[C]rashes that occur on private roads or on public paths that are not within the road reserve (e.g. segregated bicycle paths through public paths) are excluded from official records.” (CARRS-Q, 2011, page 25)


“[A]ny changes in the patterns of crash severity, hospitalisation rates and other non-fatal data from 2006 onward may reflect changes in the reporting system, rather than changes in any actual injury outcomes.” (CARRS-Q, 2011, page 25)

Data analysis by CARRS-Q was restricted to after helmet laws were introduced, which is of some concern given that the Victorian research discussed in a previous post showed significant anomalies between pre-helmet law injury rates and post-helmet law injury rates that could not be attributed to helmet use.  Additionally, the data used probably only represents somewhere between 3.5% to 11% (possibly even lower) of all bicycle crashes, and is likely to only include crashes that occur on roads and only include the most serious injuries.

Limiting the analysis only to a period after helmet laws were introduced means that:

“… the data analyses cannot provide information on whether the introduction of helmet legislation led to a reduction in the percentage of injured cyclists who had head injuries.” (CARRS-Q, 2011, page 39)

Similar to some of the research discussed in a previous post, CARRS-Q concludes that the proportion of head injuries and facial injuries was lower for those riders who were wearing a helmet.  However, also consistent with that previous research, the CARRS-Q analysis of the data noted that helmet wearing rates were lower for children and youths:

“Recorded helmet use rates are highest (approximately 80%) among injured cyclists aged 25 years or older.  Helmet use trends are the lower for younger riders, with similar rates for primary and secondary school aged children (5-11 group and 12-17 group).” (CARRS-Q, 2011, page 39)


“Wearing rates were lowest by cyclists aged under 20, with a steady increase with age.” (CARRS-Q, 2011, page 40)

As demonstrated by the research discussed in a previous post, these age groups are much more likely to have a crash.  CARRS-Q also found that:

“[b]oth helmeted and non-helmeted cyclists aged 0-4 demonstrated a high proportion of head injuries, while cyclists without helmets also had a higher proportion of lower limb injuries in this age group.” (CARRS-Q, 2011, page 39)

“Most cyclists killed are males in collisions with motor vehicles with 15-29 year olds being most commonly involved.” (CARRS-Q, 2011, pages 39 and 40)

Limiting the data only to a period when helmets were required by law, and only to roads where helmets must be worn, means that any non-helmeted crash victims included in the survey fall into a very specific category: law-breakers.  As well as the likelihood that non-helmeted cyclists belong to an age group more likely to have a serious crash, it can also be assumed that any adults riding without a helmet against the law may also be risk takers (the ‘risk’ is a hefty fine – up to $150 in some states in Australia).

CARRS-Q also concluded that injury severity was lower for cyclists wearing a helmet.  However limiting the analysis only to the very small percentage of the most serious injuries will give a false representation of any association between helmet use and crash severity.

CARRS-Q also analysed Australian bicycle fatality data it obtained from:

“ … published reports and on relevant websites. Primary references will include the Australian Transport Safety Bureau reports, “Cycle safety: A national perspective.” (2004), “Deaths of cyclists due to road crashes” (2006) and “Road Deaths Australia 2008: A statistical summary” (2009). Some of the detailed data (such as helmet wearing) is dated and any fatalities occurring in off-road riding are not included.” (CARRS-Q, 2011, page 34)


From this data CARRS-Q concluded that:

“… the number of cyclists killed per year has approximately halved since 1991 (when helmet legislation was introduced in most jurisdictions.” (CARRS-Q, 2011, page 35)

Here is the graph used by CARRS-Q, generated from the data analysed, to justify this claim:

(Source: CARRS-Q, 2011, page 35)

Despite CARRS-Q’s claims, what the above graph clearly shows is that there was no clear drop in fatalities at the time helmet laws were introduced, followed by a constant plateau as helmet laws remained constant, which would be the expected result if helmet laws had any effect on injuries and no effect on cycling participation. In fact, what the graph shows is that while there was an initial drop in 1992, the number of cyclist fatalities in 1993 actually exceeded the number of fatalities immediately before the introduction of the helmet laws. Coincidentally, the penalty for not wearing a helmet was introduced in 1993. What follows is an unsteady but gradual decline in fatalities. This graph more appropriately supports the contention that helmet laws have simply continued to reduce the number of cyclists since their introduction.

CARRS-Q admits that:

“First and foremost in a discussion of the effectiveness of bicycle helmets, it should be noted that the datasets from which these reports are created do not record the helmet use of injured persons.  Direct comparisons of the outcomes of injured persons wearing or not wearing helmets are therefore not possible.” (CARRS-Q, 2011, page 36)

So what does the CARRS-Q analyses of existing data, and all the previous research discussed in previous posts actually prove?

CARRS-Q makes the headline-grabbing claim that current helmet wearing rates are halving the number of cyclists’ head injuries in Queensland.  This claim makes a number of rather dubious assumptions. In its conclusion CARRS-Q says that, because only crashes can be examined and there is no way to randomly assign helmeted and unhelmeted participants to certain road conditions:

“ … it can always be argued that the riders who wear helmets are somehow intrinsically safer riders than those who do not, or that those who ride on footpaths are somehow different than those who ride on the road or that people who chose to cycle would have been healthier anyway.” (CARRS-Q, 2011, page 41)

The actual conclusions that can be drawn from the above fall significantly short of CARRS-Q’s bold claim.

There are some consistent findings in the research discussed above and in previous posts, including the peer-reviewed research CARRS-Q chose to ignore. Such as:

  • Children and youths are most likely to suffer a cycling related crash that is serious enough, or possibly serious enough, to be reported.
  • Children who do crash are most likely to suffer a minor head laceration that is superficial (i.e. lots of blood, nothing seriously hurt, the type of inury that an adult would have avoided by instinct or experience, for example holding their hands out break their fall).
  • Children, especially teenagers, are also the most likely not to wear a helmet.
  • Children, especially teenagers, are also most likely to give up cycling if helmet wearing is mandatory.
  • Helmet wearing significantly reduces the number of people choosing to cycle across all age groups.
  • Significantly increased numbers of people cycling make cycling safer for those that cycle, however that increased safety is likely to diminish if cycling becomes the most popular form of road transport.
  • The biggest killer of cyclists is motor vehicles, specifically articulated or rigid trucks.
  • Cycling is inherently a safe means of transport.
  • In social economic cost terms, increasing cycling will result in savings across the areas of health, transport infrastructure, pollution and productivity that outweigh any costs that can be associated with cycling-related injury.
  • The possible decreased likelihood of a serious head injury that can be attributed to wearing a helmet, is probably negated by the likelihood of a neck injury.

These findings boil down to a couple of salient points:

First, the difference in the effect of helmet laws on children and adults means that any non-age group specific assessment of helmet wearing rates for crash victims is flawed. There are significant differences in cyclist injury rates for children compared to adults.  Children cyclists are much more likely to suffer injury:

(Source: CARRS-Q, 2011, page 37)

New research by CARRS-Q itself, confirms that teenagers and other cyclists who fail to wear helmets (in jurisdictions where they are required to wear them by law) are much greater risk takers.

Any change in the age demographic of riders over a period of time is going to significantly change the injury statistics over that same period of time. Unlike the efficacy of helmets which should be clear between a time when helmets were not mandatory and helmets were mandatory (e.g. pre- and post-introduction of mandatory helmet laws), changes in the age demographic of cyclists will evoke a gradual change in statistics, such as can be seen in the graph discussed above, entitled Figure 16: ‘Numbers of cyclist (rider and pillion) fatalities in Australia and Queensland from 1991 to 2009’.

Secondly, on a community scale, the economic advantages from increased cycling far outweigh the possible disadvantages of reduced helmet use.

Thirdly, there is no clear, unequivocal evidence that wearing a bicycle helmet provides any significant protection from serious or life-threatening injuries including neck injuries. It is only clear that helmets protect from minor injuries to the head such as superficial lacerations (cuts and bruises etc.)

Fourthly, the lack of real, unequivocal evidence allows political agendas to pick and choose certain findings, so that bad policy decisions can appear to be supported by ‘science’.

This concludes our comprehensive assessment of the CARRS-Q document used by the former Queensland Government to boost support for mandatory bicycle helmet laws.

CARRS-Q Research – Part Six

Source: Sydney Morning Herald

Image Source

Why you should dismiss the CARRS-Q bicycle helmet research

Do Helmet Laws Discourage Cycling?

This is the sixth post in a series (Read Part OnePart TwoPart ThreePart Four, Part Five) looking at the non-peer reviewed CARRS-Q publication entitled “Bicycle Helmet Research“, published in 2011 and widely relied upon to support mandatory helmet laws for cyclists.  This publication was commissioned by the State Government to support its policy of mandatory helmet laws in Queensland, Australia, in the face of criticisms of its lack of support for Brisbane’s public bike hire scheme.

Two key findings of the CARRS-Q publication are that mandatory helmet laws:

“discouraged people from cycling twenty years ago when it was first introduced … [however] there is little evidence that it continues to discourage cycling.” (CARRS-Q, 2011, page 53)


“ … there is little evidence that there is a large body of people who would take up cycling if the legislation was changed.” (CARRS-Q, 2011, page 53)

The CARRS-Q publication doesn’t address the fact that only two bicycle hire schemes in the world are failing, in Brisbane and Melbourne both where helmet use is mandatory; or that the CEO of one of those schemes admits there’s no doubt mandatory helmet laws are affecting the scheme.

While the above effects on bike hire schemes are not research based, CARRS-Q also doesn’t address the continuing decline in Australian children riding to school or anywhere else.  Australian modal share of cycling has only gone from 1.1% in 2000 to 1.5% in 2009. (Australian Bicycle Council, National Cycling Strategy 2011 – 2016, page 14)

The CARRS-Q publication says that:

[c]ensus data from South East Queensland suggests that the number of journeys to work by bicycle fell after the introduction of helmet legislation … although the most recent available data suggests the absolute numbers now exceeds pre-legislation trip numbers. Measured as a proportion of mode share, bicycle trips to work have fallen from 1.6% pre-legislation … to 1.1% post-legislation.” (CARRS-Q, 2011, page 20)

So, after 20 years, the best that CARRS-Q can claim is that “absolute numbers” of cycling rates in South East Queensland now exceed what they were immediately before helmet laws were introduced.

The population of South East Queensland before helmet laws were introduced was 2.83 million. It is now 4.51 million, an increase of over 66%. The only conclusion to draw from this 20 year stagnation of absolute cycling numbers is that, around about the time of helmet laws being introduced, something happened that severely curtailed cycling in Australia.

The CARRS-Q publication also relies on Melbourne research that:

“ … demonstrated a doubling in the use of bicycles by adults in metropolitan Melbourne.  However, there was a decrease in the use of bicycles by children.  A decrease in cycling exposure of 10% was observed in children (5-11 years) and an even larger decrease of 44% for teenagers (12-17).” (CARRS-Q, 2011, page 20)

What this Melbourne research actually found was that there was a significant decrease in the numbers of children and teenage cyclists as a result of helmet laws. As discussed in a previous post, the Melbourne study also noted a possible increase in adult cyclists but recognised that this was difficult to confirm as the there was 4 years between the two surveys relied upon for ascertaining the number of adult cyclists.  The first survey was conducted in 1987/88, about three years before helmet laws were introduced.

The CARRS-Q publication also relies on data from Melbourne, Perth and Sydney that shows that cycling rates have increased over the last 5 years. Given that helmet laws were introduced 20 years ago in these cities, and rates have only increased in the last 5 years, it is difficult to draw any correlations between these recent increases and the effect of helmet laws.

During the regime of mandatory helmet laws, an entire generation has attained an age historically popular for cycling.  Australians under the age of 25 cannot remember a time when helmets were not mandatory.  It is extremely dubious to rely on these recent increases as evidence that helmet laws do not affect cycling rates.  However this is exactly what the CARRS-Q publication does.

The CARRS-Q publication concludes that:

“It is reasonably clear that [helmet laws] discouraged people from cycling twenty years ago when it was first introduced.  Having been in place for that length of time in Queensland and throughout most of Australia, there is little evidence that it continues to discourage cycling.” (CARRS-Q, 2011, page 53)

One can only assume that CARRS-Q is referring to some type of evidence other than the woeful cycling rates mentioned above.  Some kind of research specifically asking would-be cyclists whether mandatory helmet laws are the cause of their choice not to cycle.  Recent Sydney-based research addresses exactly this question, and identifies that 23.6% of adults would cycle more often if they didn’t have to wear a helmet. (Rissel et al: The possible effect on frequency of cycling if mandatory bicycle helmet legislation was repealed in Sydney, Australia: a cross sectional survey, Health Promotion Journal of Australia, page 181)

Of specific interest is the Sydney report’s findings that mandatory helmet laws discourage 19% of non-cyclists from any type of cycling. In other words, here is research that shows that existing cyclists would ride more often, and non-cyclists would start riding, if helmet laws were repealed.

It should be noted that, while criticism can be made of this study on the grounds that the questions were too subjective, the results are in accord with ABS Census data:

Percentage of trips made to place of employment by bicycle before and after introduction of mandatory helmet laws: Queensland

(Source: Summary of Characteristics of Persons and Dwellings Queensland, census data collected 1981, 1986, 1991, 1996, 2001 and 2006, Australian Bureau of Statistics.)

Recent New Zealand research also confirms these findings, finding that regular cyclists ride half as often as they did prior to mandatory helmet laws.

(Clarke: Evaluation of New Zealand’s bicycle helmet law, New Zealand Medical Journal, 2012)

CARRS-Q has ignored significant research showing that helmet laws are directly responsible for significant reductions in cycling. This position removes all credibility the CARRS-Q publication has in comparing the social economic benefits of cycling, including health, traffic congestion, pollution and infrastructure, to the possible costs associated with head injuries if mandatory helmet laws were repealed.

The last post in this series will look at CARRS-Q’s use of existing police and hospital data and available bicycle fatality data.  While CARRS-Q relies on this data to support its stance in favour of mandatory helmet laws, it is clear that the data is unreliable and that CARRS-Q utilises a number of very dubious assumptions to reach its conclusions.

CARRS-Q Research – Part Five

Cycling without helmet laws is safe. Fear is unhealthy.

Why you should dismiss the CARRS-Q bicycle helmet research

Do Economic Benefits from Cycling Outweigh The Head Injuries Prevented By Helmets?

This is the fifth post in a series (Read Part OnePart TwoPart Three, Part Four) looking at the non-peer reviewed CARRS-Q publication entitled “Bicycle Helmet Research“, published in 2011 and widely relied upon to support mandatory helmet laws for cyclists.  This publication was commissioned by the State Government to support its policy of mandatory helmet laws in Queensland, Australia, in the face of criticisms of its lack of support for Brisbane’s public bike hire scheme.

The CARRS-Q publication relies on a series of Victorian reports to find that:

“These reductions represented a considerable saving each year, for example a reduction of 40 severe head injuries (assuming $408,000 each) per year translated to savings of just over $16m per year.” (CARRS-Q, 2011, page 18)

Other researchers in other States have been critical of this series of reports.  A West Australian study has found that:

“The magnitude of the decreases suggested by [the West Australian study] are below those found by Carr et al (1995) in Victoria [the fourth study discussed in Part Four]. Their findings were that the number of bicyclists hospitalised with a head injury had declined by 40% in the first four years of the helmet wearing legislation in Victoria. The findings of the present study suggested smaller reductions of between 11% and 21% in the number of bicyclists hospitalised with a head injury …”

“The study provided no clear answer as to whether the helmet wearing legislation had been an effective countermeasure in an economic sense …”

“In monetary terms, it is unlikely that the helmet wearing legislation would have achieved net savings of any sizeable magnitude. Under the assumptions used in the study, the most favourable estimate of the Net Present Value of the bicycle helmet legislation was $2.0 million, and this calculation excluded any costs associated with reduced cycling activity.” (Hendrie et al, Road Accident Prevention Research Unit, Department of Public Health, University of Western Australia: An economic evaluation of the mandatory bicycle helmet legislation in Western Australia, Insurance Commission of Western Australia Conference on Road Safety, 1999).

This West Australian study was not mentioned at all in the CARRS-Q publication.

The CARRS Q publication also reviews a huge number of reports all of which found clear economically significant social benefits for cycling. (CARRS-Q, 2011, Chapter 2)

These benefits are estimated to be between 40 cents per kilometre to NZ$2.14 per kilometre. (CARRS-Q, 2011, page 5)

In finding that head injuries economically outweigh other benefits, CARRS-Q also quoted a 2009 survey conducted for Sydney Metropolitan Cycle Network project, stating health benefits from cycling are only 1.42 cents per kilometre.  (CARRS-Q, 2011, page 5)

However here is the actual cost analysis republished in the CARRS-Q publication (CARRS-Q, 2011, page 10):

Table 1. Estimated impact of cycling per bicycle kilometre travelled (Table 1 from PricewaterhouseCoopers, 2009).

Type of impact Benefit (2008 c/bicycle km)
Decongestion benefit 24.28
Savings in user cost 16.39
Parking cost savings 1.00
Travel time costs 0.00
Bicycle crash cost -2.03
Health benefits 1.42
Air pollution reduction 1.73
Noise reduction 0.85
Infrastructure provision 3.91
Greenhouse gas reduction 0.66
Total Net Benefit 48.22

As can be seen from the actual figures, the total social economic benefit far outweighs the costs associated with cycling injuries.

The CARRS Q report also conceded that a Copenhagen study that controlled for (and therefore negated) factors such as age, gender, education, smoking status, cardiovascular conditions and body mass index still found that the benefits of cycling:

“… equated to a 40% lower chance of dying in a given year compared to non-cyclists.” (CARRS-Q, 2011, page 3)

Despite all of this, the CARRS-Q publication states that:

“… [other researchers] conclude that “the combined evidence presented in these studies [from countries without universal helmet legislation] indicates that the health benefits of bicycling far exceed the health risks from traffic injuries, contradicting the widespread misperception that bicycling is a dangerous activity  … Our conclusion differs somewhat: cycling does have significant health benefits and therefore should be encouraged in ways that reduce the risk of the most serious of injuries … protection of the individual by simple and cost-effective methods such as bicycle helmets should also be part of an overall package of measures.” (CARRS-Q, 2011, page 10)

(Ed: we covered this strange conclusion by CARRS-Q in an earlier post)

Although a great body of research confirms there are significant health benefits to cycling, CARRS-Q position is that this research overstates the benefits because:

  • Much of the work in this area has been carried out by “advocates.” (CARRS-Q, 2011, page 3)
  • People who cycle more may be less likely to smoke and more likely to engage in other forms of physical activity. (CARRS-Q, 2011, page 3)
  • People who are already healthy may be more likely to cycle. (CARRS-Q, 2011, page 3)
  • Not enough people in Australia currently cycle long enough or often enough for there to be a significant health increase. (CARRS-Q, 2011, page 4)
  • Costs relating to cycling crashes should be calculated not in terms of human capital, but in terms of willingness to pay. (CARRS-Q, 2011, page 7)
  • The ‘safety in numbers’ effect will not be as effective if cyclists and pedestrians outnumber motor vehicles, because cyclists and pedestrians won’t know how to behave around motor vehicles. (CARRS-Q, 2011, page 8)
  • Economic benefits don’t include health costs incurred from non-crash injuries from over-exertion, such as sprains and strains. (CARRS-Q, 2011, page 10)

CARRS-Q believes that the solution is to successfully encourage cycling while retaining helmet laws. This position denies the evidence that helmet laws reduce cycling.

In March 2012 the incumbent Queensland Government (responsible for commissioning the CARRS-Q publication) released an election commitment about cycling that states:

“Cyclists currently save the economy $63.9 million dollars per year in reduced congestion costs and $9.3 million in greenhouse gas emissions.” (On your bike: Getting more Queenslanders cycling, Queensland Labor Party, 2012, page 2)

This estimate of economic benefits, just for reduced congestion and greenhouse gas emissions not including personal health benefits, noise pollution or infrastructure provision, far outweighs the social health costs of head injury considered by CARRs-Q to be only $16 million per year. (CARRS-Q, 2011, page 18)

It is clear that the CARRS-Q publication fails to take a full account of all the social economic benefits of cycling in its assessment.  It is also clear that CARRS-Q took an extremely conservative view of the proven health benefits of cycling, choosing to compare this to an overestimation of possible costs associated with cyclists’ head injuries.   In this respect, the CARRS-Q publication fails to provide a proper, unbiased costs analysis of mandatory helmet laws.

The next post in this series will look at CARRS-Q’s claims that mandatory helmet laws do not discourage cycling.  This position is fundamental to CARRS-Q’s claims about cyclists’ head injury rates (which CARRS-Q denies could be primarily caused by fewer cyclists), and CARRS-Q’s dismissal of the likelihood of significant social economic gains from increased cycling if the helmet laws were repealed.

Australia’s Helmet Law Disaster

Read the full article at The Institute of Public Affairs

MHLs are not only unnecessary and unjust, they are inconsistent. Pedestrians and car occupants are each responsible for more hospital patient days for head injuries than cyclists. Despite this, few argue that compulsory walking and driving helmets are essential for safety.

After 20 years, the results are clear: the compulsory bike helmet experiment has failed. We need to amend the law to allow adults the freedom to choose if a helmet is necessary when they cycle.

Some will still choose to wear helmets at all times, and this is a totally reasonable decision. However in many situations it is perfectly safe to go without and Australia should join the rest of the world in allowing this simple freedom.

Take action today and start enjoying the ride! Read more