Australian Helmet Experience
Summary: This paper is from the Proceedings of Velo Australis, a conference held in Fremantle, Australia, October
30, 1996. We have no comment on the content.
Is There Any Reliable Evidence That
Australian Helmet Legislation
Bicycle Federation of Australia
2 Barsden St, Cottesloe 6011, Western Australia
It is far from clear what effect, if any, Australian bicycle
helmet legislation has had on reducing the risk of head injury
to cyclists involved in crashes.
Many early reports of the effectiveness of the legislation are
seriously flawed. This is because of the very serious inadequacies
of the crash injury databases available, and because of the extreme
difficulty of apportioning any changes in injury rates with time
to one particular factor when there are very many other factors
changing at the same time.
The Australian helmet legislation was introduced as part of a
Ten-Point road safety package. The Federal government gave states
"Black-Spot" road safety money on condition that helmet
legislation, and other measures such as 0.05% blood alcohol limits,
Compulsory helmet legislation was introduced first in Victoria
effective on 1st July 1990. Helmets became compulsory in Western
Australia on 1st January 1992. Like many cyclists, I have long
promoted helmet wearing and I did not oppose the legislation as
I believed that compulsory helmet wearing would be effective.
Australian cyclists have had to "wear" the inconvenience
of the legislation. Almost nothing of the resultant Black-Spot
funds went to bicycle safety. In WA only $69,350 out of $28.3M
(0.2%) was spent on bicycle facilities. The evidence so far indicates
that our initial belief in the effectiveness of the legislation
may well have been ill-founded, and our hopes for road safety
and equity improvements as a result of the Federal funding package
The prime function of bicycle helmets is to protect the wearers
from injury to the head in the event of a crash. With the exception
of a minor advantage of an increase in conspicuity, helmets should
not decrease the risk of crashes occurring. There is the contrary
"risk compensation hypothesis" advanced by Hillman (1993a,
1993b), which suggests that people wearing helmets may adopt more
risky behaviour patterns than they would when not protected by
helmets. If valid, this would tend to increase crash rates as
wearing rates increased.
The intended purpose of the legislation in Australian states has
been to reduce head injury rates by increasing the proportion
of cyclists wearing helmets. Helmet wearing rates have increased
substantially amongst Australian cyclists as a result of the legislation,
but there is little data on how effectively helmets are secured
or fitted. Wearing rates vary amongst different age groups, and
in different geographical locations, and for different trip purposes.
Wearing rates are also affected by community perception of enforcement
levels. The available helmet usage data are limited.
The effect, if any, of the legislation in reducing head injury
risks is considerably more indirect than the effect on wearing
rates, and is very much harder to evaluate.
An Ideal Data Set
An ideal study to decide if our helmet legislation has been effective
would require complete and reliable data on all injuries to cyclists
caused by all bicycle crashes, and analogous data for all other
classes of road users for comparison. This should be available
as time series on an annual basis or more frequently, for a considerable
time period both before and after the introduction of legislation.
The methods for the collection of the data should not have changed
with time. The data should be available as soon as possible after
the end of each year to allow the effects of recent policy changes
to be studied.
It is also essential to have a reliable record of bicycle usage
if absolute injury rates are to be compared as a function of time.
If people ride more, or if usage drops, the expected number of
injuries will change even if the risk of injury to each individual
cyclist remains the same.
Bicycle Usage and Exposure Data
It is known that bicycle usage rates change significantly with
time, between states, between different age-groups, and between
different trip purposes and trip lengths. However, there are
no ongoing reliable measures of exposure of Australian cyclists
to travel risks, due to the very serious problems of measuring
both bicycle usage and cyclists' exposure to traffic levels and
vehicle speeds. It is estimated (B. Robinson, 1992, 1994) that
about 7% of vehicle trips in Australian cities and towns are taken
by bicycle. This is probably higher than the proportion of public
About 6% of trips in Perth are taken by bicycle, (DoT, 1995).
Cyclists make up about 17% of road crash hospitalisations Australia-wide
and 19% in WA, (FORS, 1995). About 80% of cyclists hospitalised
in WA are injured in single-vehicle crashes; ie those not involving
a motor vehicle, (O'Neill, 1991).
For motor vehicle transport, accurate and readily available fuel
sales data can be used as a monitor of short-term usage fluctuations.
There is no equivalent parameter available to estimate changes
in average bicycle use. There is considerable anecdotal and survey
information to suggest that bicycle usage has been inhibited by
the helmet legislation, but reliable statewide estimates of this
Police "Reported-Crash" Data
The most common injury data set available for road safety research
is the various state police "reported crash" data bases.
Unfortunately, it has long been known in Australia that the vast
majority of bicycle crashes resulting in injury are not reported
to the police. Overall only 2.2% to 3.5% of WA crashes resulting
in injury to cyclists are recorded by the police (Hendrie and
Ryan, 1994). This is very similar to the 1977 Geelong Bikeplan
study estimate of only 3% of injury crashes being reported. The
reporting rate rises with the severity of injury. In WA, fatal
bicycle crashes are reliably reported to police, only about 20%
of those requiring admission to hospital are reported, and only
0.5% of minor injury crashes are reported. Australia-wide, only
20% of road crashes resulting in hospitalisation of cyclists are
recorded by the police (FORS, 1995). Single-vehicle bicycle crash
injuries are rarely recorded by the police. Hence these data
are very seriously biased towards bicycle/motor-vehicle crashes
which comprise only about 20% of hospitalisation crashes. As
well, cyclists injured while not wearing a helmet may well be
far less likely to report the crash post-legislation than before.
It can not be assumed that reporting rates, especially for head
injuries, will be unaffected by legislation.
Injury Compensation Scheme Data
In Victoria, the Transport Accident Commission has records of
claims for injury compensation, and this has been used by Victorian
researchers. However, this is also a self-reported data set,
and may well suffer from some of the same defects as the police
reported crash data sets, especially with regard to head injury
reporting. TAC records for hospitalised cyclists (Cameron et
al, 1994) omit about 80% of those recorded by hospitals and about
56% of those recorded by the police (FORS, 1993). This means
that changes in reporting levels and practices can significantly
influence apparent injury rates derived from the TAC data. Compensation
scheme data are a useful intermediate between the police and hospital
data. However, only Victoria's scheme is a true no-fault system,
so that claim rates in other states may well be substantially
Hospital Admission Data - The Most Reliable Data Source
WA is unique in Australia in having available a published long-term
annual series of data on essentially all admissions to hospital
since 1971. This has been of invaluable assistance to bicycle
policy formulation, and provides the data upon which the majority
of this study is based. Publications from this data set on bicycle
crash injuries include Lugg (1982), Brooks and O'Neill (1988),
and O'Neill (1991).
These data are far more reliable than the police or injury compensation
scheme data, as they are collected with almost complete coverage.
They are free of many of the reporting-rate problems that beset
the other data sets. The coding practices may have changed over
time, and the proportion of "unspecified road users"
amongst the admissions has been decreasing as coding reliability
has increased. Evidence from South Australia and elsewhere suggest
that changes in hospital procedures, for instance for concussion,
may have affected the reliability of hospital records of head
injury (Marshall and White, 1994)
Hospital admission data have very little information about the
location or type of crash, so they are of limited use for detailed
crash location procedures. Combining information from both the
police records and the hospital records can be particularly valuable.
There is also a weak point in that the release of the hospital
data is often delayed by a year or so in WA. It would be very
useful for road safety policy if the data were available on a
far more rapid turnaround.
WA hospital admission data for cyclists' injuries can be presented
as absolute numbers admitted to hospital (Fig. 1), or as a proportion
of all vehicle crash hospitalisations (Fig. 2). Ratios of different
parameters can be extremely useful to compensate at least in part
for the large number of factors which affect injury rates.
Figure 1. Absolute numbers of
hospitalised cyclists (apart from
those recorded as "unspecified road
Data on Other Contemporaneous Road Safety Measures
Total road crash fatalities and injuries in Australia fell sharply
over the period of the introduction of the helmet legislation.
Published opinion varies on the weighting given to different
factors, but an economic recession and safety measures like speed
cameras, drink-driving enforcement and publicity campaigns have
all played a part. Pedestrian fatalities in Victoria fell from
159 in 1989 to 93 in 1990, the year of the helmet law. Driver
fatalities fell 32% that year as well. Road safety improvements
of this magnitude at the same time as the helmet legislation make
it hard to recognise and disentangle the effects of different
factors. Indeed, using the same "one-parameter logic"
as many of the initial helmet effectiveness reviews, it is possible
to "show" in Figure 3. that helmet legislation has substantially
reduced pedestrian fatalities in Victoria. But this is clearly
impossible. Failure to recognise external factors such as other
road safety and usage changes has devalued many Australian evaluations
of helmet effectiveness.
Figure 3: Does helmet legislation reduce pedestrian fatalities
?? The hazards of attributing changes only to one specific factor
Graphical and statistical comparisons with other data sets can
be useful for recognising common trends and discrepancies, as
shown in Fig 4.
A bicycle helmet offers protection only to a very limited part
of the body so only some injuries can be prevented or minimised
by helmet wearing. One parameter which should show the most clear
effect of helmet wearing rates is the ratio of head injuries (intracranial
(brain), scalp and skull injuries) to other injuries not preventable
by helmet wearing.
The WA data on head injuries to cyclists are compiled from all
18 injury fields, but show similar trends to those from only the
primary diagnosis field (Legge and Hendrie, 1996). They show
a long-term trend of reduction in the proportion of head injuries
to total injuries amongst hospitalised cyclists (Fig 5). However
no significant effect of the legislation can be observed. This
is the most convincing evidence that helmet legislation has not
Figure 4. Comparison with changes from 1981 rates for WA cyclist
hospital admissions, admissions of all other WA vehicle users,
and total Australian road crash fatalities. 1992 legislation
Figure 5. Percentage of head injuries amongst hospitalised cyclists
in WA. It is not possible to discern from the graph the year
of introduction of the legislation in WA (1-Jan-1992)
Cameron et al (1994) fitted a logistic regression to the pre-law
data and extrapolated it beyond the helmet law introduction.
Post-law, the only significant change from the regression line
was the 1992/93 point which lies below their 95% confidence limits.
It is likely that changes in reporting rates, hospital procedures
or some other factor can account for this discrepancy in an otherwise
relatively smooth trend (Fig 6).
Figure 6. Percentage of head injuries to other injuries in TAC
hospital admissions in Victoria.
South Australia and Queensland
The absence of analogous long-term trend information from studies
in SA (Marshall and White, 1994) (see Fig 7) and Qld (King and
Fraine, 1994), make it hard to verify the published information
claiming positive head injury reduction from the helmet legislation,
particularly given the demonstrated head injury reduction rates
over time shown in all data. D. Robinson (1996b) shows similarly
that head injury rates in Queensland do not show any significant
effect from the legislation.
Fig 7. Percentage of hospitalised cyclists with head injuries,
The SA data provide estimates of potentially preventible injuries
(PPI), plus an allowance for the uncertainty of the treatment
of suspected concussion (C) cases. Again, the data seem to show
a long-term downwards trend and little or no significant effect
of the helmet legislation.
The Qld data reported by King and Fraine (1994) are based on a
small sample area, and provide little information on the existing
trends in head injury reporting amongst hospital admissions.
It would be wise to view the Qld data when it is presented as
all-of-state data and with adequate time coverage before and after
the introduction of the legislation.
Comparisons with Head-Injuries of Other Road Users
Comparisons with the proportions of head injury amongst other
road users can be useful (D.Robinson, 1996a). In WA, the proportion
of head injuries amongst pedestrians decreased during the mid
1980s, in line with that shown amongst hospitalised cyclists (Fig
8). The common trend in both probably reflect changes in hospital
procedures. Hodge (1996) suggests that since the 1980s the use
of CT scanning of head injuries of patients who attend emergency
departments has resulted in a significant change in their diagnosis
and management. People who attend with brief loss of consciousness
are less likely to be admitted with a diagnosis of concussion
and held in hospital for observation. It is no longer at all
appropriate to attribute the long-term decline in head injury
rates to increasing bicycle helmet wearing, unless it is proposed
that this has also been protective of pedestrians at the same
time. The divergence between WA pedestrian and cyclist rates
in 1991 (before the legislation) is so far unexplained, and should
receive further study. It may just be random variation.
Fig 8. Analogous head injury percentage plots for both hospitalised
cyclists and pedestrians in WA.
Costs of Helmet Legislation
WA's helmet legislation has diverted resources from preventing
bicycle crashes into increasing helmet wearing rates. For instance,
about 50% of the WA Police Bicycle Safety Section's time is devoted
to enforcing the helmet law. At the same time, about 80% of cyclists
on the road at night are riding without lights, with very little
chance of getting apprehended. There is a very strong case that
enforcement should be directed to crash prevention measures.
While helmet legislation has been introduced, many residential
streets have been made far less safe for cyclists by uncontrolled
traffic-management which discounts our needs. This has significantly
increased the risk of bicycle crashes by introducing squeeze-points
recognised as hazardous in the Geelong Bikeplan in 1977. Reduction
of known generic hazards for cyclists is a recognised crash prevention
countermeasure, however very little has been done, and many more
hazards are being created than rectified.
Apart from the helmet legislation, Federal, state and local governments
have very largely ignored and discounted bicycle safety. By any
parameter; either per user, per trip, per crash hospitalisation
or per km, bicycle transport and safety is grossly under-resourced.
In WA, many cyclists regard Bikewest as a largely powerless organisation,
frequently ignored and over-ruled by other road and planning authorities.
Commitments to provision of facilities for bicycle transport
have not been fulfilled, while cyclists still get tickets for
not wearing helmets. Resources should be devoted to prosecuting
traffic engineers who endanger cyclists with poor road and path
design and motorists who speed rather than cyclists who fail to
The helmet legislation has discouraged people from using bicycle
transport. This has decreased community fitness levels, increased
risks of serious diseases due to exercise deficit, and hence probably
increased community health costs (Roberts et al, 1995). It is
likely that these disbenefits are far more significant than any
possible injury prevention benefit from helmet legislation.
A detailed overall review of Australia's helmet legislation and
its effectiveness should be carried out using all available data
from all states. In particular, it is crucial that reliable hospital
admission data be used, rather than incomplete surrogates like
police reported-crash data and injury compensation scheme claims.
It is requested that other states follow the invaluable lead
of the WA Health Department in collecting data on road crash hospital
admissions and making it readily available to researchers .
It is also crucial that a nationwide database of hospitalised
road crash victims, including bicyclists, be established. Apart
from aiding road safety policy, this would help to overcome the
very serious misallocation of road safety funding which arises
from the use of police "reported crash" data to allocate
"Black-Spot" funding and other resources within road
authorities. The Federal Office of Road Safety was publishing
nationwide hospital admission data from the National Injury Surveillance
Unit for 1990, and 1991 (FORS, 1993, 1995). Unfortunately, FORS
has discontinued publication of this valuable comparison between
the Police "estimates" and the actual hospitalisation
figures. It is vital that all states make hospital admission
data available in the time frame that is needed for road safety
Should Others Introduce Helmet Legislation?
Any countries or jurisdictions considering the introduction of
compulsory helmet wearing laws should look very closely at the
available data to see if it still supports such a move in light
of the ambiguous Australian experience. It is essential that
reliable evaluation methodologies be recognised, and the common
shortcomings of both databases and interpretation which bedevilled
the early Australian evaluations be avoided.
Resources devoted, on the European model, to improving facilities
for cyclists and to reducing urban speed limits are likely to
be far more cost-effective than the introduction of helmet legislation.
These measures must be considered as a valid alternative to helmet
legislation or as a vital and integral part of such legislation.
It is crucial that a good and extensive data base of regional
or national hospital admissions, and if possible hospital casualty
department treatments be assembled for the decade or so preceding
the legislation. This is needed to allow a reliable comparison
with data collected after the introduction of any legislation.
It is fair to say that, so far, there is no convincing evidence
that Australian helmet legislation has reduced the risk of head
injury in bicycle crashes. It is not clear why the legislation
has not been more effective.
Acknowledgments I would like to acknowledge the foresight
of the WA Health Department in collecting its invaluable Hospital
Morbidity data set; the regular cooperation of Peter Somerford;
encouragement, assistance and provision of WA data from Delia
Hendrie and Matthew Legge of Roadwatch; and useful suggestions
from Dorothy Robinson and Ian Roberts.
Brooks, B.H, and O'Neill, M, (1988). "Bicycle hospitalisations,
WA, 1981-1987", Health Statistics Unit, Health Department
Cameron, M., Newstead, S., Vulcan, P., and Finch, C. (1994), "Effects
of the compulsory bicycle helmet wearing law in Victoria during
its first three years". Proc. ARRB Workshop on Pedestrian
and Bicycle Safety, Melbourne.
DoT (1995). Metropolitan Transport Strategy, Department of Transport,
FORS (1993). "Road crashes resulting in hospitalisation,
Australia, 1990". Federal Office of Road Safety, Canberra.
FORS (1995). "Road crashes resulting in hospitalisation,
Australia, 1991". Federal Office of Road Safety, Canberra.
FORS (1996) "Road fatalities Australia, 1995 statistical
summary", Federal Office of Road Safety, 1996
Geelong Bikeplan (1977). Main report, Geelong Regional Commission.
Hendrie, D, and Ryan, G.A., 1994 "A 'best' estimate of
the number of pedal cyclists injured in Western Australia: Some
policy implications". Proc. 17th ARRB conference, Brisbane.
Part 5, 253-268
Hillman, M. (1993a). "Cycle helmets; the case for and
against". Policy Studies Institute, London.
Hillman, M. (1993b). "The case for and against promoting
helmet wearing". Proc. 21st Summer meeting, PTRC European
Transport, Highways and Planning; Traffic Management and Road
Safety. 13-17th September, 1993. University of Manchester.
Hodge, J (1996). Emergency Department, Fremantle Hospital. Personal
communication 10th October.
King, M. and Fraine, G. (1994) "Bicycle Helmet legislation
and enforcement in Queensland 1991-1993. Effects on helmet wearing
and crashes". Proc. ARRB Workshop on Pedestrian and
Bicyclist Safety and Travel, Melbourne.
Legge, M, and Hendrie, D., (1996). "Road Injury Database;
Subset of WA Health Department Hospital Morbidity Database".
Unpublished. Road Accident Prevention Unit, University of Western
Lugg, M, (1982) "Hospital morbidity statistics, pedal
cycle accidents, 1971-1980". Statistics Branch, Public
Health Department of WA.
Marshall, J., and White, M., (1994). "Evaluation of the
compulsory helmet wearing legislation for bicyclists in South
Australia". Office of Road Safety report series 8/94
O'Neill, M., (1991) "Bicycle hospitalisations, WA, 1988-1990",
Health Services Statistics Unit, Health Department of WA.
Roberts, I, Owen, H., Lumb, P, MacDougall, C. (1995) "Pedalling
health. Health benefits of a modal transport shift". Adelaide.
Robinson, B.W. (1992), "Bicycle usage and safety in Australia.
An estimate of current levels and trends". Proc. AusBike
92, 97-99. Melbourne
Robinson, B.W. (1994). "Bicycle usage and safety in Australia;
a 1994 review". Bicycle Federation of Australia
Robinson, D.L. (1996a). "Head injuries and bicycle helmet
laws". Accident analysis and prevention. 28/4 463-475
Robinson, D.L, (1996b) "Head injuries, helmet laws and
health". Proc. Velo Australis, Perth (this volume)
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