Teaching

1. Improving Road safety:
From public health to psychology
© WHO, 2007
Aymery Constant, PhD
Maître de conférence / Lecturer
EHESP / French School of Public Health
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Mobility
• Every person has to move during lifetime
• Going to school, work, shopping, travel...
• Different transportation modes: motorized and
non motorized
But this is not a safe activity

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Road mortality and injuries:
A major public health issue
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Road traffic crashes
• 1.2 million deaths a year (road mortality)
• 20-50 million injuries/disabilities (road
injuries)
• 11th leading cause of death
• Account for 2.1% of all deaths globally

5. Global status report on road safety 2013
© WHO, 2007

6. Drowning
7.3%
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Distribution of global injury mortality by cause
Suicide
16.9%
Violence
10.8%
War
3.4%
Poisoning
6.7%
Falls
7.5%
Fires
6.2%
Road traffic injuries
22.8%
Other intentional injuries
0.2%
Other unintentional injuries
18.1% Road traffic injuries
account for 23% of
all fatal injuries
worldwide
Source: WHO Global Burden of Disease project, 2002, Version 1

7. Indicators of road traffic safety
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8. Absolutes Figures
• Number of injuries indicating the number of people injured in
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road traffic crashes
Not very useful for making
comparisons. A large proportion of
slight injuries are not reported
• Number of deaths indicating the number of people who die as
a result of a road traffic crash
Gives a partial estimate of the magnitude of
the road traffic injury problem, in terms of
death

9. • Fatalities per 10 000
vehicles
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showing ratio of fatalities to number of motor
vehicles. Shows probability of vehicle involvement
in fatal crashes
It omits non-motorized transport and
declines with motorization
Relative figures
• Fatalities per 100 000
pop
impact of road traffic crashes on human
population as a public health problem.
Useful for estimating severity of crashes.
Might decline in countries with very large
populations

10. Others indicators
• Fatalities per
vehicle-kilometre
travelled
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Useful for making international
comparisons, decreases with motorization
Does not take into account non-motorized
travel
• Disability-adjusted life
years (DALYs)
Estimate healthy life years lost to
disability and mortality.
DALYs combine both mortality and
disability but do not include mental
health consequences

11. Distribution of road fatalities
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12. ROAD TRAFFIC DEATH RATES PER 100 000
POPULATION (WHO, 2012)
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Evolution of road mortality
over time
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Brazil

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India

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Vietnam

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TRENDS (WHO, 2012)

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Key points
Decreasing trends in road traffic deaths in high-income
countries, despite high levels of motorization
(number of motor vehicle per capita)
Increasing or stable trends in most low- and
middle-income countries, despite low to average (but
increasing) levels of motorization
Traffic injuries and deaths represent a serious threat to
development in low-income countries, and jeopardise
the pursuit of equity in health

21. Differences in road fatalities
between low-middle and high
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income countries
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France

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Brazil

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Thailand

25. Proportion of road deaths by transportation
0% 20% 40% 60% 80% 100%
Australia
Delhi, India
Kenya
Malaysia
Netherlands
Sri Lanka
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modes
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Pedestrians
Motorized 4-wheelers
Bicyclists Motorized 2-wheelers
USA

26. Vulnerable road users
 Pedestrians, cyclists,
motorcyclists and moped riders
are considered as vulnerable
since they benefit from little
or no external protective
devices that would absorb
energy in a collision.
 They constitute with almost no
exception the weak party in a
road traffic crash
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27. Vulnerable road users
 Half of the road fatalities occurring each year concern
vulnerable road users (VRUs). They predominate in low
and middle income countries, where levels of
motorization are low
 With children and elderly being overrepresented among
victims
 Safety of VRUs became a health priority for
International Agencies such as the WHO and the UN in
2004 (WHO report on road safety, 2004)
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28. Road deaths, 2012
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29. Impact of policies toward VRUs
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Thailand
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Back to Thailand…

31. Regulations in Thailand
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In Europe
Death risk for 100 million person / kilometres travelled:
 13.8 for motorised two-wheelers
 6.4 for pedestrians
 5.4 for bicyclists
 0.7 for car users
 0.07 for bus and coach passengers.
Source: European Transport Safety Council
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Helmet use
According to Reviews conducted by Authors from the
Cochrane Collaboration:
- Helmets are effective in reducing head injuries in
motorcyclists who crash by 69% and death by 42% (Liu et al.,
2009)
- Helmets provide a 63 to 88% reduction in the risk of
head, and severe brain injury for all ages
(Thompson, Rivara, & Thompson, 2009)

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Road fatalities: Florida
Helmet law for motorcyclists was lifted
Source: NHTSA (USA)

35. Europe standardized rates
Source: CARE Database / EC
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of query: August 2008

36. From Islamabad, Pakistan
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39. Conclusion
 High rates of mortality among VRUS might be due to several
interacting factors :
 Road infrastructure not adapted (bicycle lanes;
separation between VRU and motorized traffic; etc.)
 Few/No policies towards VRU
 Risk behaviours and/or poor law enforcement
 Absence of protective behaviour (helmet use..)
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40. Constant & Lagarde
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41. What can be done?: An example of intervention
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study towards cyclists
Investigating Helmet Promotion for Cyclists:
Results from a Randomised Study with Observation of
Behaviour, Using a Semi-Automatic Video System

42. Helmet use
 In France, helmet is not mandatory for cyclists
 The efficacy of lawful mandatory helmet use is in dispute,
because:
 of possible negative side-effects such as risk compensation
 and possible decline in the number of cyclists (see
Robinson, BMJ)
 We launched a randomized comparative study that
measured for the first time the efficacy of non legislative
interventions to promote helmet use among cyclists
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43. Methods
 Participants were recruited in a borrow-a-bike municipal
program. They completed a questionnaire on their attitudes
toward road safety and helmet use.
 They were assigned to one of the four groups:
 Control group
 Group #1: They received an information on helmet benefit
 Group #2: They received a helmet
 Group #3: They received both
An ID coloured code was put on their rear mudguard.
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44. Recruitment center
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45. Municipality Bicycles
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(Not good
looking) helmets
were given to
groups #2 and #3

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standardized
brochures were
given to groups #1
and #3

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49. Outcomes
 Five automatized observation sites were deployed in the
urban centre of Bordeaux. Two of them made observations in
both directions, leading to a total of seven observation spots
 A first camera was programmed to detect moving objects,
isolate cyclists, and calculate speed
 A second synchronised high-definition camera
automatically took a photo of each detected cyclist from
behind at a 45 degree angle.
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50. were connected to the main
our settings via the
INSERM
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54. Data collection
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55. Data collection
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An ignored risk:
Umbrella and Cycling

63. Conclusion
 Helmet wearing rate ?
 Efficiency of information to promote helmet use?
 Duration of effect ?
 Cues to improve helmet wearing rates ?
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Road injuries: Risk Factors
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65. Male gender
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67. Road deaths affect primarly young
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people
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Risk factors
Behaviours
• A study estimate that more than 90% of collisions occur
because of human factor (see above)
• Some Risky road behaviour increase the likelihood of traffic
crashes
• Excessive speed
• Driving while alcohol-intoxicated
• Sleepy driving

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Risk factors
• Some behaviours increase the severity of a crash
• Seats-belts not used (4-wheel drivers)
• Helmet not used, no protective clothes (2-wheel drivers)
• Insufficient car protection
• Some behaviours increase both
• Excessive speed
• Driving while alcohol-intoxicated

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Effect of alcohol in traffic
 Alcohol directly weakens driver skills:
- less attention and visual detection
- longer reaction time
- problem with keeping course
 Accident risk increases exponentially depending on Blood
Alcohol Content (BAC):
- 0,5 g/l: 1,5 times higher than sober
- 0,8 g/l: 2 times higher than sober
- 1,3 g/l: 15 times higher than sober
- 1,8 g/l: 50 times higher than sober
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Accident risk of drink drivers at
different BAC-levels

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Risk factors
Road and environmental factors
• Traffic density
• Time (day/night; week-end/other; vacations; other)
• Reduced visibility (absence / poor street lighting)
• Type of road (highway, rural roads..), quality of the road surface
• Road engineering and infrastructure
• Unforgiving infrastructures
• Protection for pedestrians/cyclists (bicycle lanes, traffic island..)

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Risk factors
Vehicle characteristics
• Roadworthiness
• Lighting
• Braking
• Handling
• Speed management
• Etc.

75. The psychology of road traffic
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Crashes
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76. The Haddon Matrix
 Conceptual model that applies basic principles of public
health to the problem of traffic safety. extremely useful and
effective tool for revealing where and when to best conduct
traffic safety interventions
• Highlight injuries in terms of causal and contributing
factors, as well as in terms of a time sequence consisting
of pre-event, event, and post-event phases.
© WHO, 2007
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77. The Haddon Matrix
 Consists of four (or three) columns representing the
causal agents in the crash: the driver, the vehicle, and
the physical and socio-economic environment
 Three rows representing time phases:
 pre-crash (before a potential vehicle collision),
 crash (the actual event),
 and post-crash (the immediate aftermath).
© WHO, 2007
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78. Haddon Matrix
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Factors
Vehicles and equipment Environment
Phase Human
Pre-crash Crash
prevention
Information
Attitudes
Impairment
Police enforcement
Roadworthiness
Lighting
Braking
Handling
Speed management
Road design and
road layout
Speed limits
Pedestrian
facilities

79. Haddon Matrix
© WHO, 2007
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Factors
Vehicles and equipment Environment
Phase Human
Pre-crash Crash
prevention
Information
Attitudes
behaviourt
Police enforcement
Roadworthiness
Lighting
Braking
Handling
Speed management
Road design and
road layout
Speed limits
Pedestrian
facilities
Crash Injury
prevention
during the
crash
Use of restraints
Impairment
Occupant restraints
Other safety devices
Crash protective design
Crash-protective
roadside objects
Forgiving
infrastructure

80. Haddon Matrix
© WHO, 2007
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Factors
Vehicles and equipment Environment
Phase Human
Pre-crash Crash
prevention
Information
Attitudes
behaviour
Police enforcement
Roadworthiness
Lighting
Braking
Handling
Speed management
Road design and
road layout
Speed limits
Pedestrian
facilities
Crash Injury
prevention
during the
crash
Use of restraints
Impairment
Occupant restraints
Other safety devices
Crash protective design
Crash-protective
roadside objects
Forgiving
infrastructure
Post-crash Life
sustaining
First-aid skill
Access to medics
Ease of access
Fire risk
Rescue facilities
Congestion

81. Haddon Matrix
© WHO, 2007
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Factors
Vehicles and equipment Environment
Phase Human
Pre-crash Crash
prevention
Information
Attitudes
behaviour
Police enforcement
Roadworthiness
Lighting
Braking
Handling
Speed management
Road design and
road layout
Speed limits
Pedestrian
facilities
Crash Injury
prevention
during the
crash
Use of restraints
Impairment
Occupant restraints
Other safety devices
Crash protective design
Crash-protective
roadside objects
Post-crash Life
sustaining
First-aid skill
Access to medics
Ease of access
Fire risk
Rescue facilities
Congestion

82.  Psychological and sociological models are of interest
in studying human factors influencing the likelihhod
of a crash before its occurrence (pre-crash)
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Information
Attitudes
Norms
Police
enforcement
Behaviours

83. Theory of planned behaviour (TPB)
 Azjen (1991) suggested various factors combine to form an
intention to act a certain way.
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Attitudes toward
behaviour
Subjective
norms
Perceived
behavioural
control
Intention to
behave in a
certain way
Behaviour

84. Application of the TPB to road safety
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85. Application of the TPB to road safety
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86. Application of the TPB to road safety
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87. Application of the TPB to road safety
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Predict intention
Predict self reported
behaviour
Do not predict actual
behaviour

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Develop and evaluate intervention
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How to reduce road fatalities ?
Evidence-based interventions
• Usually, preventive interventions are assessed through
longitudinal studies
• The statistical unit is a target population
• An outcome of interest is assessed before and after a
preventive intervention (number of fatalities or head injuries
when testing helmet law)
• Ecological or “before-after” studies

93. Recent changes in French road safety
14 000
12 000
10 000
8 000
6 000
4 000
2 000
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0
number of fatalities
Number of road fatalities

94. Recent changes in French road safety
14 000
12 000
10 000
8 000
6 000
4 000
2 000
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0
number of fatalities
40,00%
35,00%
30,00%
25,00%
20,00%
15,00%
10,00%
5,00%
0,00%
speed excesses %
fatalities up to 2001 fatalities from 2001

95. The case of France
• France is a high income country
• Good infrastructure (highway, rural roads) and vehicles
• High level of motorization
• Numerous information campaigns against risky road
behaviours since the 70’s
• Road fatalities in 1976: 16 000
• Decrease in road fatalities: 1975 -2001: - 2% on average
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• 2002 - 2009: -44.4%

96. Automatic Speed cameras In France
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98. Influence on attitudes towards
road safety and road behaviours
 How attitudes toward traffic safety have changed between
2001 and 2004?
 How road behaviours have changed between 2001 and
2007
 What are the determinants of these changes?
 Relevance: Providing useful insights into what occurred in
this remarkable period and help assessment of whether
observed behavioural changes are stable.
© WHO, 2007
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99. Methods: a prospective study in
the GAZEL cohort
 Participants: Current employees or recent retirees of the
French national electricity and gas company, who volunteered to
participate in a research cohort, known as the GAZEL cohort.
 The same questionnaire was used to assess behaviours
and attitudes toward road safety in 2001, 2004 and 2007
 Data was also available from the cohort database (gender, age,
occupational category, alcohol consumption, etc.)
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100. Study on attitudes and road behaviors and
in the GAZEL cohort
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2001 2002 2004
First
Assessment
2003 2005 2006 2007

101. Study on attitudes and road behaviors and
in the GAZEL cohort
French government
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2001 2002 2004
First
Assessment
2003 2005 2006 2007
enact a zero
tolerance policy

102. Study on attitudes and road behaviors and
in the GAZEL cohort
French government
© WHO, 2007
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2001 2002 2004
First
Assessment
2003 2005 2006 2007
enact a zero
tolerance policy
Increased law enforcement:
-Automatic speed cameras
- Alcohol controls
Phoning and driving forbidden
End of indulgences (ticket fixing)
Legal sanctions harshened
Dramatic decreases in road
fatalities and in road injuries

103. Study on attitudes and road behaviors and
in the GAZEL cohort
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2001 2002 2004
First
Assessment
2003 2005 2006 2007
Second
Assessment
Third
Assessment
French government
enact a zero
tolerance policy

104. Influence of increased enforcement on attitudes
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105. Influence of increased enforcement on attitudes
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106. Conclusion 1
Increased traffic law enforcement measures led to increasing
support for current restrictions between 2001 and 2004.
Even if support for additional traffic law enforcement began to
wane slightly in 2004 (-4%), a large part of participants
remained in favour of strengthening law enforcement
related to speeding (61%) and drink driving (80%).
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107. Influence of increased enforcement on excessive speed
(reported speed at least 20 km/hour above the limit)
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108. Influence of increased enforcement DWI
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109. Conclusion 2
Between 2001 and 2007, the proportion of participants who
reported having driven at speeds at least 20 km/hour above the
limit decreased in built-up areas, on rural roads and on
highways
But the recent crackdown on road violations by the French
government has failed to deter DWI, despite declines in
overall alcohol consuption over the same period
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110. Unlike speeding, detection of DWI offenders cannot be achieved
through automated devices, thus limiting the probability of
being arrested for DWI.
DWI remained unchanged although attitudes and norms
rejecting such behaviour are very high in the population
And despite the fact that DWI is identifed by 92% of drivers as
a major cause of fatal crash (SARTRE Study)
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Conclusions

111. Safety is mainly about….
1) behaviour
2) behaviour change
3) and (in the case of road safety) law enforcement
© WHO, 2007
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Conclusions

112. First, change behaviours (hardest part of the job, really)
Then, health issues, and all related costs, will (hopefully)
decrease,
And finally, attitudes and norms will follow …
© WHO, 2007
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Implications for health actions and
prevention initiatives