Transcript Slide 1

Medically At-Risk Drivers
Evidence-Based Decisions
Change of Focus:
Older Drivers
vs.
Medically At-Risk Drivers
In 2008 WA introduced new laws requiring the
Mandatory Reporting of Medical Conditions.
All drivers with a long term medical condition
that has the potential to impair driving ability
must notify the licensing department.
Crash Involvement Rate
Rate of MVAs per Kilometre Driven
Driver Age Group
Sources: COTA National Seniors, ACT (2004) Cerrelli , E. (1989) Older Drivers: The Age Factor in Traffic Safety.
Age - Illness Association
Australians Aged 65+
• 80 % have at least 1 chronic
condition
• 50% have at least 2 chronic
conditions
• Co-morbidities & polypharmacy are the norm
Sources: ABS (2008); Freedman, Martin & Schoeni (2002)
Increased At Fault Crash Risk
At Fault Crash Risk By Diagnosis
Source: Diller, E et al. (1998)
Prevalence of Cognitive Impairment
1 in 4 people over 65 years have
cognitive impairment
Source: *(CSHA, 1991)
Diagnosis Inadequate For Fitness To
Drive Decisions
eg.
In the early stages of dementia:
2/3 will be unsafe to drive
but
1/3 remain safe to drive
Revoking licence based on diagnosis alone
is discriminatory to those who are still safe
But... how do you best determine at what
point someone becomes unsafe?
This publication is intended for use by
any health professional involved in
assessing fitness to drive, including:
Medical Practitioners
(GPs & Specialists)
Occupational Therapists
Physiotherapists
Psychologists
Optometrists
Categories of Medical Conditions
EPISODIC
PERSISTENT
(eg. MI, Epilepsy, Hypoglycaemia)
(eg. Head injury, dementia)
No question about driving
ability when an event occurs
No question about likelihood
of event - it is ongoing
Assessment question is
“likelihood of the event”
Assessment question is
“competence of the driver”
Assessment Issue:
Judgement about the risk level
Assessment Issue:
Measurable outcome impairment
Science unlikely
Consensus guidelines =
Suggested best practice
Evidence based driving
evaluations = best practice
™
DriveABLE
S.I.M.A.R.D.
Screen for Identifying Medically At -Risk Drivers
D.C.A.T.
DriveABLE Cognitive Assessment Tool
D.O.R.E.
DriveABLE On-Road Evaluation
Motor Speed and Control
Assesses the time between the appearance of a visual stimulus
in an unpredictable location & driver’s response.
Shifting of attention, response speed, and accurate movements
are involved in task performance.
Measures:
Reaction time
Motor speed
Movement Accuracy
Span of Attentional Field
Driving requires an ability to attend to the road ahead while
simultaneously responding to events occurring in the periphery.
Measures:
Ability to maintain focus on centrally presented items;
While simultaneous identifying peripheral visual stimulus
Spatial Judgement & Decision Making
Turns, merges, & crossing traffic are associated with high crash rates
Difficult for cognitively impaired drivers due to impaired judgement
& decision making
Complex task requiring speed, gap & acceleration judgments
Measures:
• Spatial judgement
• Response time
• Collision rate
Speed of Attentional Shifting
Assesses how quickly the driver can shift focus of
attention from one stimulus to another.
Measures:
Time to respond when attention is
• Correctly focused
• Inappropriately focused
• Left unfocused
Disengagement of attention
Executive Function
Higher cognitive function related to our ability to organise, plan,
prioritise, manage & make decisions.
Evaluates how well driver can hold information in working memory
while responding to other stimuli.
Identification of Driving Situations
Series of short videos of real driving scenes
The driver makes decisions about each driving scenario
Provides information about the driver’s interpretation of
road situations
Measure:
Ability to identify hazardous
situations & take appropriate
action
DriveABLE On Road Evaluation
Specifically designed to identify the errors known to
be related to competence decline
Protects those drivers who remain competent from
being unfairly penalised
DriveABLE
Driven by Research
Assessment Date: May 27, 2004
Name:
The Driver
Address:
123 My Road
Anytown, Anywhere
Assessment Language:
Date of birth:
Age:
Health Care #:
Driver's License #:
English
June 22, 1927
73
1234567
99999
Phone:
555-5555
Referred by:
Physician, MD
Phone:
555-5555
Fax:
555-5555
________________________________________________________________________________________
Cognitive Assessment Report
Performance Outcome:
Age-normed performance was commensurate with a decline in driving ability.
Summary of Findings:
In-Office Competence Assessment:
Mr. Driver was given sufficient individualized practice on each task to enable a valid assessment and
appeared cooperative and effortful during testing.
Assessment Outcome Measures (in Standard Scores)
Well Below Below Average Above
Motor Speed/Control
0.0
Span of Attentional Field
*-5.2
Spatial Judgment and Decision Making
*-1.6
Speed of Attentional Shifting
*-3.4
Executive Function
*-2.7
Identification of Driving Situations
*-10.7
Overall Performance: 99% predicted probability of road test failure.
Mr. Driver’s overall performance outcome indicates cognitive abilities have declined and driving
performance may be compromised.
Validation Field Testing
Accuracy of predicting Road Test Results
In Office
Road Test Results
Pass
Fail
Predict
Pass
30%
3%
In-determinant
25%
18%
2%
21%
Predict
Fail
43%
Needed road
test95%
to resolve
5%
competence
Error
Accuracy
Rate
51%
Pass/Fail
Identified
*Florida
www.DriveABLE.com.au