CADReS Score Sheet for Geriatric Driving Assessment
What CADReS Is NOT
The Clinical Assessment of Driving Risk in the Elderly (CADReS) is not a validated or recommended tool for evaluating driving safety in older adults. Despite its name suggesting clinical utility, research demonstrates that CADReS has poor diagnostic accuracy with a sensitivity of 0.81 but specificity of only 0.32 and an area under the curve of just 0.57—barely better than chance 1.
Superior Assessment Approach
Clinicians should instead use a targeted multi-domain assessment focusing on cognitive function (particularly executive function), visual attention, and visuospatial abilities, as these predict on-road driving safety far more accurately than the CADReS tool 2, 3, 1.
Key Assessment Components
Cognitive Testing (Highest Priority)
- Trail-Making Test Part B: This executive function test shows the strongest correlation with actual driving performance and should be the primary cognitive screening tool 1
- Useful Field of View (UFOV) Divided Attention test: Combined with age, this visual attention measure achieves a C-statistic of 0.90 for predicting at-risk drivers 2
- NAB Driving Scenes test: When combined with UFOV, this further improves prediction of unsafe driving 2
- Mini-Mental State Examination: While less specific than executive function tests, MMSE scores combined with computerized maze tasks yield sensitivity of 0.61 and specificity of 0.84 1
Visual Function Assessment
- Visual acuity testing: This is one of the three best predictive parameters for on-road fitness 4
- Visual attention capacity: Different cognitive domains predict distinct aspects of driving—speed of processing specifically predicts safety errors during active driving tasks 3
Motor and Physical Assessment
- Physical flexibility testing: This ranks among the top three predictive tests for on-road outcomes 4
- Visuospatial construction abilities: These specifically predict baseline safety errors (errors occurring without secondary task demands) 3
Knowledge Assessment
- Road sign recognition: This practical test is among the best predictors of actual driving competence 4
Clinical Decision Algorithm
Step 1: Identify High-Risk Indicators
Ask directly about:
- Falling asleep while driving or drowsiness-related accidents 5
- Recent crashes or near-misses due to sleepiness, fatigue, or inattention 5
- History of hypoglycemia while driving (for diabetic patients) 5
- Syncope or unexplained falls (30% of older adults presenting with falls may have had syncope) 5
Step 2: Screen for Modifiable Risk Factors
- Medications: Review for sedating medications, anticholinergics, benzodiazepines, and other high-risk drugs 5, 6
- Sleep disorders: Screen for obstructive sleep apnea, particularly if AHI ≥20 events/hour with daytime sleepiness 7
- Metabolic issues: Check for hypoglycemia risk in diabetics, thyroid dysfunction, or other metabolic derangements 5, 6
- Comorbid conditions: Assess for depression, neurological disorders, and cognitive impairment 5
Step 3: Perform Targeted Testing
If any high-risk indicators are present:
- Administer Trail-Making Test Part B as primary screen 1
- Conduct UFOV Divided Attention testing if available 2
- Test visual acuity and physical flexibility 4
- Assess road sign knowledge 4
Step 4: Make Driving Recommendation
Immediate driving cessation if:
- Patient reports falling asleep while driving 7
- Recent drowsiness-related accident occurred 7
- Severe OSA (AHI ≥20) with treatment non-compliance 7
- Two or more episodes of severe hypoglycemia in past 12 months (increases crash risk by 12%) 5
Refer for formal on-road evaluation if:
- Trail-Making Test Part B shows significant impairment 1
- UFOV testing indicates divided attention deficits 2
- Multiple cognitive domains show decline 3
- Patient has cognitive impairment (MCI or dementia) but no immediate high-risk features 2
May continue driving with monitoring if:
- Mild OSA (AHI <20) without excessive daytime sleepiness 7
- Controlled medical conditions without functional impairment 5
- Normal performance on cognitive and functional testing 1
Critical Pitfalls to Avoid
Do not rely on age alone: Chronological age is a poor predictor of driving safety; functional assessment is essential 5
Do not use AHI alone for OSA patients: Clinical assessment of sleepiness is more important than the apnea-hypopnea index by itself 7
Do not overlook amnesia: Older adults may not recall loss of consciousness events, making history unreliable—consider syncope even when falls are reported 5
Do not assume hyperglycemia impairs driving: Unlike hypoglycemia, hyperglycemia lacks scientific evidence for driving impairment 5
Do not forget state reporting requirements: Familiarize yourself with local mandatory reporting laws for high-risk drivers 5
When to Refer
Refer to driving rehabilitation specialist when:
- Office-based testing suggests impairment but patient strongly desires to continue driving 5
- Patient has residual deficits after stroke or neurological event 5
- Adaptive equipment or restricted licensing might enable safe driving 5
Behind-the-wheel assessment remains the gold standard for determining actual driving competence, and office-based tools serve primarily as screening instruments to identify who needs formal evaluation 5.
Treatment Before Return to Driving
For patients with treatable conditions: