Driving

Question 1

What is the ‘Chain of Causality’ by Rizzo and Kellison (2010)?

Answer 1

A conceptual framework in which cognitive abilities and impairments determine specific driving behaviors and safety errors which predict crashes. (SEE lecture slides)

Driving behavior is safe or unsafe as a result of errors at one or more stages in driving tasks

Question 2

What is metacognition related to driving?

Answer 2

Metacogntion = awareness of cognitive and behavioral performance.
In driving: awareness of (1) cognitive functions, (2) driving behavior, (3) vehicular performance, (4) road conditions, (5) rules of the road, (6) self-impairment and (7) compensatory strategies to mitigate effects of impairments

Question 3

What aspects other than those proposed in the Chain of Causality are of relevance while driving? (7)

Answer 3

• emotional state
• personality (risk taking)
• level of arousal (e.g. sleepiness, fatigue)
• psychomotor factors
• general mobility
• metacognition
• drug effects

Question 4

Name 3 patientgroups in who show increased crash risk

Answer 4

1. Severe TBI
2. Dementia - later stages (discrepancies across studies possibly due to earlier diagnosis nowadays)
3. Progressive neurological conditions (PD, MS)

Question 5

Why is information derived from crash records difficult to interpret? (3)

Answer 5

• Crashes are multifactorial
• Self-reports and police records are incomplete
• Minor crashes are often not reported

Question 6

Name 4 factors affecting driving abilities on which evaluation of fitness to drive is based

Answer 6

1. Motor impairment
2. Visual impairment
3. Cognitive impairments
4. Emotions and personality

Question 7

What could be a reason for the sometimes weak association between motor impairment and driving ability?

Answer 7

People with severe motor impairments don’t drive and people with minor impairments adapt -> so you don’t get to take this group into account that much

Question 8

What kind of reaction times appear (not) to be an important predictor of safety to drive?

Answer 8

Simple reaction time (=measure of motor speed) appears NOT to be an important predictor

Complex reaction time appears to be an important predictor

Question 9

How are visual impairments measured in assessing safety to drive? (3 aspects?)

Answer 9

Assessment of:

• Visual acuity
  
  • > be able to read a number plate at 20 m
• Visual fields
  
  • > field of at least 120 degrees horizontal
• Visual inattention
  
  • > visual inattention tests

Question 10

What are two predictors of driving safety with regard to visual impairments?

Answer 10

• Constrast sensitivity
• Useful field of view
  (= area in which visual information can be acquired and processed without eye and head movement)

Question 11

What is the Useful Field Of View measurement?

Answer 11

Composite measure combining three measures of visual processing and cognition:

• visual processing speed
• divided attention
• selective attention

Poor UFOV measures associated with poor driving performance and increased crash rates

Equipment often only available at special driving-assessment centres

Question 12

Name 6 relevant cognitive functions involved in driving

Answer 12

1. Visual perception
2. Attention
3. Spatial awareness
4. Speed of information processing
5. Executive functions
6. Time estimation

Question 13

Name 3 important aspects of automatic attention processes in driving + meanings

Answer 13

1. Vigilance (sustained attention)
   = ability to maintain attention over prolonged period of
   time during which infrequent response-demanding
   events occur
2. Focussed attention
   = control of focus of attention
   
   • necessary to be aware of marked changes in
     environment during saccades or blinks (‘change
     blindness’)
3. Shifting (flexibility)
   = shifting focus of attention among relevant tasks

Question 14

Name 2 motivations to use cognitive assessments in the context of driving abilities

Answer 14

1. Identification of patients for referal to on-road driving evaluation
2. Identification of functions that are of concern (to be checked out especially at on-road driving evaluation)

Question 15

Why is it important to do an on-road driving evaluation at the appropriate time?

Answer 15

In recovering conditions -> referral when cognitive recovery is sufficient

In degenerative conditions -> should be an identification of when patients start to be a risk (assessment should not be to early or to late)

Question 16

What were the results of the study by Korteling and Kaptein (1996) about the use of neuropsychological tests used to assess fitness to drive in patients wih TBI?

Answer 16

31% of variance in driving performance accounted by combining perceptual speed, time estimation, coma duration and reported driving experience

71% accuracy in classifying participants in safe and unsafe drivers when comparing predicted performance with on-road performance

46% of unfit drivers predicted to be fit

-> Conclusion (by Classen et. al., 2009, review): neuropsychological tests are not sufficiently predicitve of driving performance to replace on-road test

Question 17

What specifity/sensitivity levels have been found of neuropsychological testing as a predictor of safe driving in MS patients?

Answer 17

Cognitive abiloties can predict safety to drive in people with MS:

• 88% predictive accuracy
• 84% correct classifications
• high 89% specifity (identification of fit drivers to be fit)
• low 25% sensitivity (identification of unfit drivers to be unfit)

Question 18

What specifity/sensitivity levels have been found of neuropsychological testing as a predictor of safe driving in PD patients?

Answer 18

Correct classification of: (2 studies)

• 68% of patients as safe or marginal drivers
• 72% of patients as safe or unsafe drivers
• > statistical model better in predicting safe drivers

Question 19

What and can neuropsychological tests predict fitness to drive in dementia?

Answer 19

Many studies focus on MMSE of MoCa

• relationship found to be low
• MMSE found to be not sufficiently reliable

Better option: testing of driving skills recommended in patients with scores lower than 24

Study: only large effect size with visuospatial skills assessment

Question 20

Name 3 tests/test batteries appropriate for patients with various aetiologies in predicting fitness to drive

Answer 20

1. Cognitive Behavioral Drivers Inventory
2. Rookwood Driving Battery
3. DriveSafe

Question 21

What are 3 problems with using neuropsychological measures to assess fitness to drive?

Answer 21

1. Elderly drivers more often misclassified
2. Some tests shown to be only sensitive in specific patient groups
3. Often low sensitivity for detecting unsafe drivers

Question 22

If neuropsychological assessment is not a good enough predictor of fitness to drive, then what can it be used for in this context? (3)

Answer 22

1. Identification of those patients with preserved cognition, i.e. those with very minor cognitive deficits
2. Identification of those patients who are clearly so unlikely to be safe to drive that a road test is unappropriate
   - > 2 groups identified who do not have to undero an on-road assessment
3. Npsy assessment also useful to determine the timing when recommend patients to take on-road assessment

Question 23

What are 4 general problems with available studies on the neuropsychological assessment to estimate fitness to drive?

Answer 23

1. Often small sample sizes
2. Inclusion of tests assessing abilities thought to be relevant for driving (i.e. no accepted set of tests or standard)
3. Predictors identified depend on what else has been assessed in that study
4. Many studies are retrospective

Question 24

What are 5 downsides of on-road assessment (= golden standard)?

Answer 24

1. Development of road tests to ensure that novice drivers know and can apply rules of the road -> but not to test experienced drivers with impairements
2. Road testing carry risks inherent in the real world road environment
3. Road tests depend on weather, daylight, traffic and driving course -> very random
4. Lack of evidence on the accuracy of a single road test in relation to driving ability in daily life
5. Considerable differences in standards between different on-road assessors, both between and within centres

Question 25

What are advantages (3) and disadvantages (4) of using a driving simulator to assess driving abilities?

Answer 25

Advantages:
- safe of risks associated with on-road testing
- exact replication of (experimental) road conditions
under which driving is assessed
- good face validity

Disadvantages:
- abilities assessed in simulators may not correspond to
on-road driving, i.e. no predicition of on-road driving
(lack of validation)
- very expensive, rarely available
- no clear standards of simulator settings and test
conditions yet
- simulator adaptation syndrome (i.e. autonomic
symptoms including nausea and sweating)

Question 26

What are 4 associated consequences of being told one can no longer drive (in PD patients)?

Answer 26

1. loss of independence
2. depression
3. low self-esteem
4. reduced activities

Question 27

Why is it that , despite regulations, many patients continue or resume driving without assessment and advice? (3)

Answer 27

• Partly on purpose, partly by not knowing
• Partly because medical practitioners are often unaware of regulations
• Partly because medical practitioners find regulations difficult to use

Question 28

Name three possible driving retraining programmes and related study outcomes

Answer 28

1. Training of Useful Field of View (UFOV)
   - > better UFOV in patients with UFOV training than in patients with traditional visual perception training, BUT no difference in on-road driving
2. Driving lessons
   - > not evaluated yet (expensive)
3. Training on a driving simulator
   - > stroke patients recieving driving simulator training vs. cognitive training: significant difference in proportion allowed to resume driving (73% simulator vs 42% cognitive)