Reverse Haddon Matrix:
A Planning Tool for Prevention Research
Mary E. Aitken MD MPH,
Beverly K. Miller, M Ed, Hope Mullins, MPH
University of Arkansas for Medical Sciences
Arkansas Children’s Hospital, Little Rock, Arkansas
• Approximately 10 million ATVs in use; 79%
for leisure, 21% for work/chores
• Used for farming, industry, military/law
enforcement, medical, transportation
• 800+ deaths and 400,000 injuries annually
costing $22.3B in 2007
• About 20% deaths and 30% of injuries
occur in children under 16 years of age
All-terrain Vehicles
GAO, All-terrain Vehicles: How They are Used, Crashes, and
Sales of Adult-sized Vehicles for Children’s Use, 2010
ATV Injury TrendsATV Injury Trends, United States
US CPSC, 2010
Safety Challenges
• Evidence base: Strong
• Message: ―Buckle Up‖
• Exposure: Universal
• Policy approach: Clear
• Policy evidence: Strong
• Evidence base: Limited
• Message: Complex and
controversial
• Exposure: Limited
• Policy approach: Complex
• Policy evidence: Muddled
Motor Vehicle Safety ATV Safety
Human
Factors
Vehicle
Factors
Physical
Environment
Socio-
economic Environment
Pre-event Driver training
experience, size, maturity
Vehicle size, HP,
safety features, stability
Weather,
Site of use, obstacles
Training,
Legislation (helmets, etc)
Event Helmet use,
other protective gear
Trauma
systems
Post-
event
Healthcare/
EMStraining
Road/trail
accessibility
Trauma
systems,Insurance,
Health Care,
Rehabilitation
Trail designVehicle size,
speed
GPS or other
signaling devices
Haddon Matrix for ATV Injury
Key Messages,
Skimpy Evidence Base
• Use an age-appropriate ATV
• Wear a helmet
• Get training
• No passengers
Reverse Haddon Matrix
Human Vehicle Physical Socio-Economic
Pre-Crash How do distractions
(passengers, other) affect
risk of ATV crash?
Differential for
experience/maturity?
How does training impact
risk of ATV crash?
How do
alcohol/impairment impact
ATV crash risk for different
age groups?
To what extent does
protective gear reduce risk
of crash?
How does driving
experience influence risk
of ATV crash for children?
To what extent are
crashes due to novice
drivers?
Physical readiness and
maturity assessments
from the industry, 4-H, and
– has anyone evaluated
them?
Are crashes of novice
How does vehicle stability
differ and influence crash
risk?
Do other vehicle
modifications (speed
governors, etc) affect
crash risk?
Are newer vehicles safer
(and how)?
Does maintenance of
vehicles substantially
impact crash risk?
What is lifetime risk of
crash for a vehicle?
Crash rate per vehicle mile
driven—more appropriate
measure of exposure/risk.
Are ATVs with smaller
motors involved in fewer
or less severe crashes? If
so, is it a machine or
human issue?
Are ATVs regulated by
American industry safer
than those unregulated
from foreign markets?
Are there minimum
standards for a trail for
public use? Signage?
Slope grades and
conditions? Are there
standardized criteria and
consistency from place to
place?
Do different surfacing
materials matter?
Are groomed trails safer?
If so, would encouraging
their use improve injury
rates or just increase
exposure?
Do we really know the
barriers to not having
training or are we
speculating?
Access to training
barriers—
cost/time/convenience?
Awareness—does general
education work? Dose?
Training for kids?
Appropriate or risky?
Evaluation of policies:
Deterrence to riding:
insurance, liability,
prohibition
Modify riding behavior:
require training,
experience, protective
gear
Reverse Haddon Matrix
• Use of the reverse matrix approach
revealed gaps in knowledge and evidence
• Several areas were identified for research:
– Impact of education and training
– Helmet use (effectiveness and barriers to use)
– Gaps in understanding of machine/rider
interaction and performance in real-world use
– Effectiveness of state level policy approaches
Impact of Education
Hunter Safety Education Project
• Targeted high exposure rural youth
• Convenience sample of AR hunter safety course
• Improved short-term knowledge about
helmet/safety gear, passenger, use on roads
• Next questions:
– Does knowledge improvement translate to behavior
change?
– Is education alone (no hands-on training) effective?
Williams J Rural Health, epub October 2010
Engineering Questions: Helmets
• Helmets worn in <20% of fatal ATV crashes
• Reported helmet use in rural youth riders is very low
• Little is known about the performance characteristics of protective gear
– Helmet effectiveness—reduction of 42% for mortality; 62% reduction in any head injury
Rodgers, Accident Anal Prev,1990
Helmet Effectiveness
• National study of ATV riders of all ages admitted to trauma centers
• Unhelmeted riders: – 62% increased risk for any TBI
(OR=1.62, 95% CI 1.49-1.76, p<.001)
– 3 times more likely to sustain severe TBI (OR=3.19, 95% CI 2.68-3.79, p>.001)
– more than twice as likely to die in hospital (OR=2.58, 95% CI 1.81-3.67, p<.001)
• Next questions: – What are barriers to helmet use among adult and child riders?
– Does distribution of a helmet at the time of training increase adoption of helmet use?
Bowman et al, Injury Prevention, 2009
• Little is known about the real-life
performance characteristics of ATVs,
especially with children on board
• Qualitative studies demonstrate that
parents and youth do not understand or
acknowledge stability and other risks
Vehicle Stability and Performance
Engineering Research
Thorbole et al, SAEM, 2011
• State-level legislation widespread
• Impact of these policies is equivocal
• Analysis of patterns in policy in progress
• Next questions:
– Do helmet laws reduce head/brain injury?
– Do helmet and/or other laws decrease injury
and death?
Effectiveness of Policy
Next Steps Using Matrix Tool
Crash What is the extent of helmet and other
protective gear use in crashes? Helmet use at
time of crash declined 37% pre/post NC law
that includes mandatory helmet use for all
users among pts < 18yrs admitted to trauma
(McBride et al. 2011)
By how much does helmet & other protective
gear reduce injury in crashes? There is now
competing messages/information. Significant
decreases in close-head injury, spinal cord
injury, and soft-tissue injury but increase in
long-bone fractures suggesting that helmet
laws may be having positive impact. (Bansal et
al. 2008) although helmet use has not been
associated w/ decreasing spinal cord injury
(Orsay et al. 1994).
Helmet use did not reduce the number of
injuries, but did reduce severity. Helmet use
related to higher component GCS and FIM
communication scores and patients w/ higher
scores more likely discharged to home. Need
helmet design characteristics to confirm impact.
(Kute et al. 2007).
Nearly ½ of ATV-related head and neck injuries
involved skull fracture, perhaps signifying lack
of helmet use in this population or the severity
of trauma (Wand et al. 2007).
Children not wearing helmet had 5x greater
odds of severe head or neck injury and almost
4x great odds of severe chest injury. Odds of
severe chest injury are nearly 80% higher
under law implementation. (McBride et al.
2011)
How does the shifting of passengers during a
crash affect type and severity of injury?
Rollover proclivity studies similar to MV will be
helpful in determining likelihood and cause of
What types of injury and severity can result
from various scenarios of ATV size, speed?
Increases in engine size and top speeds have
been associated w/ increasing rate of injury
(Rogers and Adler 2001). Increase in weight
may be significant during rollovers and end-
over-end crashes ( 1993). These changes
may explain increase in long-bone fractures
and number of patients w/ extremity AIS
scores 3 of greater, although other injuries did
not increase (Bansal et al. 2008).
Can we predict number and severity of injuries
based on driver, machine, and terrain
characteristics?
95% of children injured have been shown to
be riding adults-sized ATVs (CPSC, 2005).
Children < 12 years larger portion injured and
more likely to have lower extremity fractures.
Older children more likely to have pelvic
fractures (Kellum et al. 2008).
Can we predict number and severity of injuries
based on application – work, recreation, or
racing?
Use of in a recreational area was found to be
a factor in increased mortality across genders
and age. (Krauss et al. 2010)
40% injuries in Utah registries (trauma, ED,
hospital, and death records) 2001 – 2005
occurred on off-road recreational land and
<1% occurred during farm or work activities.
(Finn & McDonald 2010)
Are weather and terrain
assumptions based on other
wheeled crashes?
47% crashes between 4 – 8
pm (Helmkamp et al. 2008).
What months? If most were
during non-DST months, were
crashes related to poor visibility
of environment due to
darkness?
To what extent are crashes a
result of intentionally risky
driving, such as through high
rates of speed, impaired
driving. 36 ATV-related spinal
consults; average age 13.7 yrs.
Of 24 pts. w/ neuro
abnormalities: 23 were on ATV
for recreation; 13 were under
the influence[12 alcohol]. Other
contributing factors: use of
ATV after sundown [7 cases].
Excessive speed or racing [10
cases] (Sanfilippo et al. 2008).
How do injury rates differ
between use on trails and
undersigned riding locations?
Overall culture of ATVs
evolving because of
organizations and rider clubs
sponsor education
emphasizing protective gear
(Bansal et al. 2008).
In , law requires training for use
in agri and forestry industries,
but not for recreational use by
children. Case studies of 4
peds trauma pts who had been
What is the extent of ATV injuries seen
by local physicians and hospitals? 6 of
10 patients w/ foot injuries were seen
at another facility before transfer to
ACH. 7 injuries occurred in rural areas
(Thompson et al. 2008).
Is the only lit I found that refers to
other hospitals. Other studies are from
trauma centers and identify methods of
transport only.
Are underinsured crash injuries more
or less likely to receive adequate care?
35% admissions for nonfatal injuries
did not have any form of health
insurance (Brandenburg 2007).Might
be interesting follow up for Jim in WV
since link between non-high school
grads and underinsured.
• Progress in prevention of ATV injury in
children remains elusive
• Use of a structured ―reverse Haddon
matrix‖ tool revealed gaps in evidence and
helped identify researchable questions
• The tool has also been helpful in tracking
developments in the field
• Applying such a tool may be helpful in
other emerging or challenging areas of IP
Conclusions
