Table 3.
Study details of included studies on Alzheimer’s disease
| Authors (year) | Number of participants (n) AD/controls (C) | Age (years) mean ± SD AD/controls (C) | Driving assessment | Cognitive/motor assessments | MMSE mean ± SD for AD/controls (C) | Main findings |
|---|---|---|---|---|---|---|
| Barco et al. (2015) | 60 AD/32 C | AD: 74.2 ± 8.5/C: 70.7 ± 8.1 | On-road | AD8, SBT, Clock drawing, TMT, Maze test, UFOV, Visual closure test | – | 62% of AD patients failed the on-road test versus 3% of controls AD patients who failed made more errors in driving straight and turning compared to pass group |
| Bhalla et al. (2007) | 84 AD/44 C | AD (safe): 75.3 ± 7.2/AD (unsafe): 77.3 ± 5.7/C: 73.6 ± 9.1 | On-road | – | – | 19% of AD patients were classified as unsafe drivers versus none of the controls |
| Bieliauskas et al. (1998) | 9 AD/9 C | AD: 70.4 ± 6.0/C: 71.7 ± 4.6 | On-road | MMSE, Visual search test, Reaction time test, Figure-ground perception test, WCST, SILS | AD: 19.4 ± 3.1/C: 27.9 ± 1.5 | AD patients made more total driving errors compared to controls Errors in turning were the most frequent |
| Bixby et al. (2015) | 75 AD/no C | 76.6 ± 6.3 | On-road | – | – | Ratings by clinicians and spouses were poorly associated with driving performance. Ratings by adult children were most related to driving |
| Brown et al. (2005) | 31 AD/24 C | AD: 76.9 ± 5.4/C: 72.0 ± 10.3 | On-road | – | AD: 25.1 ± 3.6/C: 29.1 ± 1.2 | AD patients performed worse compared to controls on the road test |
| Brown et al. (2005) | 50 AD/25 C | AD (mild): 73.2 ± 8.3/AD (very mild): 77.1 ± 5.3/C: 72.4 ± 10.2 | On-road | – | AD (mild): 21.5 ± 3.9/AD (very mild): 24.9 ± 3.6/C: 29.1 ± 1.2 | AD patients had worse overall driving scores compared to controls 9/50 (18%) were classified unsafe by driving instructor versus none of the controls Prediction by physician was associated with driving test |
| Carr et al. (2011) | 99 AD/no C | 74.2 ± 9.0 | On-road | AD8, Visual acuity, Pelli–Robson, SBT, Clock drawing, TMT, Digit span, UFOV, Visual perceptual test, SMT, Rapid pace walk, 9-hole peg test | – | 65% of AD patients failed the on-road test Combination of clinical tests was able to accurately classify safe/unsafe drivers (AD8, CDT, TMT-A, SMT; sensitivity = 67%, specificity = 94%) |
| Cox et al. (1998) | 29 AD/21 C | AD: 72.0 ± 8.6/C: 70.1 ± 10.0 | Simulator | MMSE | AD: 21.2 ± 4.6/C: 28.7 ± 9.6 | AD patients more often drove off the road, drove slower, had less brake pressure, and had more difficulty turning left compared to controls |
| Dawson et al. (2009) | 40 AD/115 C | AD: 75.1 ± 7.7/C: 69.4 ± 7.0 | On-road | MMSE, CFT, WAIS-R block design, BVRT, TMT, ALVT, JLO, COWA, UFOV, Pelli–Robson, Visual acuity, SFM, Get-up-and-Go | AD: 26.5 ± 2.9/C: not reported | AD patients made more total driving errors compared to controls Lane violations were the most common error |
| Duchek et al. (1998) | 78 AD/58 C | Not reported | On-road | BNT, WMS, BVRT, WFT, WAIS information, bock design, digit symbol, Visual search task, Visual monitoring task, UFOV | – | Error rate and reaction time during visual search were the best predictors of driving performance |
| Duchek et al. (2003) | 50 AD/58 C | AD (mild): 74.2 ± 7.8/AD (very mild): 73.7 ± 7.0/C: 77.0 ± 8.6 | On-road | – | – | 41% of mild AD and 14% of very mild AD patients were rated as unsafe drivers. Lane changing and signaling were more impaired with increasing dementia severity |
| Fitten et al. (1995) | 13 AD/24 C | AD: 70.0 ± 7.4/C: 71.8 ± 6.8 | On-road | MMSE, Clock drawing, Visual tracking, Vigilance, Divided attention, Short-term memory task | AD: 23.2 ± 2.6/C: 29.2 ± 0.9 | AD patients drove slower, had lower driving scores and committed more errors than controls |
| Fox et al. (1997) | 19AD/no C | 74.3 ± 6.4 | On-road | MMSE, JLO, BVRT, TMT, VFDT, WAIS-R picture completion, block design, digit symbol substitution | 21.3 ± 2.8 | 63% of AD patients failed the on-road test Neuropsychological tests were not associated with total driving score |
| Frittelli et al. (2009) | 20 AD/19 C | AD: 72.0 ± 5.5/C: 68.9 ± 6.3 | Simulator | MMSE, Visual reaction task | AD: 22.3 ± 3.8/C: 29.1 ± 1.5 | AD patients had worse simulated driving performance compared to controls |
| Hunt et al. (1997) | 65 AD/58 C | AD: 73.7 ± 7.8/C: 76.8 ± 8.6 | On-road | – | – | 29% of AD patients were classified as unsafe drivers versus 3% of controls |
| Lafont et al. (2010) | 20 AD/56 C | AD: 73.3 ± 4.9/C: not reported for total sample | On-road | MMSE, BVRT, Semantic fluency, Cancellation test, DSST, Go/No go test, Stroop, Stop signal, Finger tapping, Reaction time task | AD: 26.4 ± 2.2/C: 29.0 ± 1.1 | 6/20 (30%) AD patients versus 1/56 (2%) controls were judged unsafe drivers Cognitive functioning (e.g., speed of processing) was associated with an increased risk of unsafe driving (DSST cutoff <25, sensitivity = 75%, specificity = 92%) |
| Lincoln et al. (2006) | 42 AD/33 C | AD: 71.0 ± 8.9/C: 68.5 ± 5.7 | On-road | MMSE, SDSA, SORT, Stroop, TEA, VOSP, Letters and Cube, BADS, AMIPB, Balloons test | AD (median): 23/C (median): 29 | 27% of AD patients were judged as unsafe drivers versus none of the controls Composite battery of cognitive tests was predictive of driving safety (cutoff = 5, sensitivity = 67%, specificity = 100%) |
| Manning et al. (2014) | 75 AD/47 C | AD: 76.7 ± 6.2/C: 71.9 ± 7.8 | On-road | MMSE, Clock drawing | AD: 25.1 ± 2.8/C: 29.5 ± 0.7 | AD patients had a higher error rate on the road test compared to controls (54.7% versus 14.9%) Clock drawing had low predictive value of driving performance |
| Ott et al. (2005) | 50 AD/no C | 75.7 ± 6.6 | On-road | – | 23.7 ± 4.0 | 18% of AD patients were classified as unsafe drivers |
| Ott et al. (2008) | 84 AD/128 C | AD: 75.7 ± 7.0/C: 73.5 ± 9.1 | On-road | – | AD: 24.1 ± 3.6/C: 29.1 ± 1.1 | 15% of AD patients failed the on-road test versus none of the controls |
| Ott et al. (2008) | 88 AD/45 C | AD: 75.8 ± 6.9/C: 73.6 ± 9.0 | On-road | MMSE, Maze task, CFT, TMT, Finger tapping task, HVLT | AD: 24.0 ± 3.5/C: 29.1 ± 1.1 | 19% of AD patients were unsafe drivers versus 2% of controls Road navigation was associated with maze navigation Composite battery with maze task, HVLT and TMT-A correctly classified 78.2% of all subjects as safe/unsafe |
| Paire-Ficout et al. (2016) | 18 AD/18 C | AD: 72.7 ± 4.8/C: 74.5 ± 5.4 | On-road | MMSE, Verbal fluency, BVRT, Cancellation test, Digit symbol substitution, Go/No go test, Stroop, Stop signal, Finger tapping, Reaction time task, Rotation task | AD: 26.7 ± 1.9/C: 29.3 ± 0.9 | AD patients showed planning difficulties during left turns and were slower compared to controls |
| Piersma et al. (2016) | 81 AD/45 C | AD: 72.3 ± 9.4/C: 76.3 ± 4.7 | On-road and simulator | MMSE, TMT, Clock drawing, Cube drawing, Maze test, ATAVT, Traffic test, Reaction time, Hazard perception test | AD: 23.2 ± 3.7/C: 28.8 ± 1.1 | 50.6% of AD patients failed the on-road assessment versus 4.4% of controls AD patients had worse lane keeping on the driving simulator compared to controls |
| Rizzo et al. (1997) | 21 AD/18 C | AD: 71.5 ± 8.5/C: 71.9 ± 5.5 | Simulator | RCFT, TMT, WAIS-R block design, WAIS-R information, WAIS-R digit span, BVRT, COWA, Pelli–Robson, UFOV | – | No difference between AD patients and controls in number of crashes Cognitive and visual tests were predictive of crashes |
| Rizzo et al. (2001) | 18 AD/12 C | AD: 73.0 ± 7.0/C: 70.0 ± 4.7 | Simulator | RCFT, BVRT, TMT, COWA, WAIS-R block design, WAIS-R information, WAIS-R digit span, Facial Recognition, Pelli–Robson, UFOV | – | Six of 18 AD patients crashed during simulator test versus none of the controls Cognitive tests were predictive of crashes |
| Stein et al. (2011) | 17 AD/63 C | AD (mild): 71.2 ± 8.7/AD (very mild): 74.3 ± 12.2/C: 73.5 ± 6.9 | Simulator | – | – | AD patients had impaired vehicle control, difficulties lane keeping, drove slower, and made more judgmental errors compared to controls |
| Uc et al. (2004) | 32 AD/136 C | AD: 75.9 ± 6.2/C: 64.0 ± 11.4 | On-road | MMSE, COGSTAT, AVLT, BVRT, RCFT, JLO, WAIS-R block design, TMT part B, COWA, UFOV, SFM, Visual acuity, Contrast sensitivity | AD: 26.3 ± 2.9/C: not reported | AD patients performed worse on a route following task compared to controls Safety errors could be predicted by verbal memory, attention and visuospatial abilities |
| Uc et al. (2005) | 33 AD/137 C | AD: 76.1 ± 6.3/C: 64.3 ± 11.4 | On-road | MMSE, COGSTAT, AVLT, BVRT, RCFT, JLO, WAIS-R block design, TMT part B, COWA, UFOV, SFM, Visual acuity, Contrast sensitivity | AD: 26.1 ± 3.0/C: not reported | AD patients identified fewer landmark and traffic signs compared to controls and committed more safety errors |
| Uc et al. (2006) | 61 AD/115 C | AD: 73.5 ± 8.5/C: 69.4 ± 6.7 | Simulator | AVLT, RCFT, WAIS-R block design, BVRT, JLO, TMT part B, COWA, COGSTAT, UFOV, Contrast sensitivity, Visual acuity | AD: 25.6 ± 3.8/C: not reported | No differences in crash rates between AD patients and controls AD patients slowed down more abruptly compared to controls |
| Yamin et al. (2016) | 20 AD/21 C | AD: 78.5 ± 7.2/C: 77.0 ± 5.9 | Simulator | MMSE, DRS-2, VOSP, TEA, UFOV |
AD: 24.0 ± 4.9/C: 29.0 ± 1.3 | AD patients performed poorer on almost all driving outcome measures compared to controls |
| Yi et al. (2015) | 28 AD/no C | 65.6 ± not reported | Simulator | MMSE, DPT, TMT part B, RFMT | 24.1 ± 2.4 | AD patients performed best using single, simple auditory driving navigation instructions |
AD Alzheimer’s disease, AD8 Assessing Dementia-8 screening interview, ADL activities of daily living, AMIPB adult memory and information processing battery, ATAVT Adaptive Tachistoscopic Traffic Perception Test, AVLT Auditory Verbal Learning Test, BADS Behavioral Assessment of the Dysexecutive Syndrome, BNT Boston Naming Test, BVRT Benton Visual Retention Test, C controls, CDR Clinical Dementia Rating Scale, CFT Complex Figure Test, COGSTAT composite measure of cognitive impairment, COWA Controlled Oral Word Association, DPT Doors and People Test, DRS Dementia Rating Scale, DSST Digit Symbol Substitution Test, HVLT Hopkins Verbal Learning Test, JLO Judgement of Line Orientation Test, MMSE Mini-Mental State Examination, SBT Short Blessed Test, SDSA Stroke Drivers Screening Assessment, SFM Structure from Motion, SILS Shipley Institute of Living Scale, SMT Snellgrove Maze Test, SORT Salford Objective Recognition Test, TEA Test of Everyday Attention, TMT Trail Making Test, UFOV useful field of view, VOSP visual object and space perception battery, WAIS-III Wechsler Adult Intelligence Scale-III, WAIS-R Wechsler Adult Intelligence Scale-Revised, WCST Wisconsin Card Sorting Test, WFT Word Fluency Test, WMS Wechsler Memory Scale