Background
Methods
Participants and demographic data
Apparatus and driving scene
Statistical analysis
Results
Demographics
Demographics/Clinical variable | Young(N = 29) | Old(N = 27) | Significance |
---|---|---|---|
Age in years [mean ± SD] | 31.5 ± 4.2 | 70.3 ± 3.8 | t(54) = −35.951, p < 0.001 |
MoCA score [mean ± SD] | 29.2 ± 1.0 | 28.5 ± 1.4 | U = 286.0, p = 0.069 |
Trail making test A (sec) [mean ± SD] | 21.7 ± 5.6 | 36.9 ± 12.7 | U = 73.5, p < 0.001 |
Trail making test B (sec) [mean ± SD] | 45.3 ± 13.6 | 84.4 ± 31.4 | t(54) = −5.962, p < 0.001 |
Clock drawing test [mean ± SD] | 6.9 ± 0.4 | 6.6 ± 0.9 | ns |
Timed up & Go (sec) [mean ± SD] | 7.4 ± 0.8 | 7.8 ± 0.8 | t(54) = −2.048, p = 0.045 |
Years of driving experience [mean ± SD] | 12.0 ± 4.6 | 46.8 ± 7.1 | t(54) = −21.935, p < 0.001 |
Weekly mileage [mean ± SD] [range] | 247.5 ± 282.3 [4 - 1186] | 128.4 ± 112.1 [8 – 466] | ns |
Best far visual acuity [mean ± SD] | 1.16 ± 0.13 | 0.93 ± 0.25 | U = 187.5, p < 0.001 |
Contrast sensitivity (binocular) [mean ± SD] | 1.95 ± 0.00 | 1.91 ± 0.11 | U = 333.5, p = 0.033 |
Mesopic visual acuity [number (%)] | Χ2(4) = 7.996, p = 0.092 | ||
Contrast 1:2 | 28 (96.6) | 19 (70.4) | |
Contrast 1:2.7 | 0 (0) | 3 (11.1) | |
Contrast 1:5 | 1 (3.4) | 2 (7.4) | |
Contrast 1:23 | 0 (0) | 1 (3.7) | |
Nothing seen | 0 (0) | 2 (7.4) | |
Glare sensitivity [number (%)] | Χ2(4) = 24.059, p < 0.001 | ||
Contrast 1:2 | 29 (100) | 11 (40.7) | |
Contrast 1:2.7 | 0 (0) | 5 (18.5) | |
Contrast 1:5 | 0 (0) | 4 (14.8) | |
Contrast 1:23 | 0 (0) | 1 (3.7) | |
Nothing seen | 0 (0) | 6 (22.2) |
Visual exploration behavior
Driving on a straight stretch
DWELL[%](SD) | DURATION[s](SD) | ||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|
Young | Old | Age | Light | Age x light | Young | Old | Age | Light | Age x light | ||
Street
| Day | 48.2 (8.5) | 55.5 (11.7) | F(1,43) = 3.0 p = 0.090 η2 = 0.085 | F(1,43) = 1.5 p = 0.229 η2 = 0.033 | F(1,43) = 1.0 p = 0.330 η2 = 0.022 | 0.8 (0.3) | 1.1 (0.4) | F(1,43) = 7.7 p = 0.008 η2 = 0.152 | F(1,43) = 3.1 p = 0.085 η2 = 0.068 | F(1,43) = 0.2 p = 0.682 η2 = 0.004 |
Night | 52.7 (14.3) | 55.9 (13.7) | 1.0 (0.4) | 1.2 (0.6) | |||||||
Road signs
| Day | 18.5 (6.3) | 17.4 (12.2) | F(1,43) = 0.3 p = 0.616 η2 = 0.006 | F(1,43) = 2.2 p = 0.146 η2 = 0.049 | F(1,43) = 0.0 p = 0.899 η2 = 0.000 | 0.6 (0.2) | 0.7 (0.4) | F(1,43) = 2.3 p = 0.138 η2 = 0.050 | F(1,43) = 1.6 p = 0.222 η2 = 0.034 | F(1,43) = 0.1 p = 0.742 η2 = 0.003 |
Night | 20.9 (9.3) | 19.5 (10.1) | 0.7 (0.3) | 0.8 (0.2) | |||||||
Environment
| Day | 4.2 (5.0) | 1.5 (1.9) | F(1,43) = 5.3 p = 0.026 η2 = 0.110 | F(1,43) = 0.0 p = 0.873 η2 = 0.001 | F(1,43) = 0.9 p = 0.363 η2 = 0.019 | 0.5 (0.3) | 0.3 (0.2) | F(1,43) = 2.5 p = 0.118 η2 = 0.056 | F(1,43) = 0.1 p = 0.740 η2 = 0.003 | F(1,43) = 2.9 p = 0.095 η2 = 0.063 |
Night | 3.2 (4.3) | 2.2 (3.9) | 0.4 (0.4) | 0.4 (0.4) | |||||||
Rear
-view mirror
| Day | 6.0 (4.6) | 3.3 (5.1) | F(1,43) = 6.3 p = 0.015 η2 = 0.129 | F(1,43) = 6.8 p = 0.013 η2 = 0.136 | F(1,43) = 0.2 p = 0.696 η2 = 0.004 | 0.6 (0.3) | 0.3 (0.4) | F(1,43) = 3.6 p = 0.066 η2 = 0.076 | F(1,43) = 0.6 p = 0.445 η2 = 0.014 | F(1,43) = 4.1 p = 0.050 η2 = 0.086 |
Night | 3.9 (3.3) | 1.8 (2.3) | 0.5 (0.4) | 0.5 (0.5) | |||||||
Side mirror left
| Day | 0.1 (0.3) | 0.1 (0.7) | F(1,43) = 2.6 p = 0.696 η2 = 0.004 | F(1,43) = 3.7 p = 0.062 η2 = 0.078 | F(1,43) = 0.1 p = 0.775 η2 = 0.002 | 0.1 (0.1) | 0.1 (0.2) | F(1,43) = 0.1 p = 0.795 η2 = 0.002 | F(1,43) = 3.8 p = 0.059 η2 = 0.081 | F(1,43) = 0.5 p = 0.473 η2 = 0.012 |
Night | 0.0 (0.0) | 0.1 (0.3) | 0.0 (0.0) | 0.02 (0.1) | |||||||
Side mirror right
| Day | 1.7 (2.1) | 1.4 (1.5) | F(1,43) = 0.9 p = 0.357 η2 = 0.020 | F(1,43) = 1.3 p = 0.265 η2 = 0.029 | F(1,43) = 0.1 p = 0.769 η2 = 0.002 | 0.4 (0.4) | 0.4 (0.4) | F(1,43) = 0.0 p = 0.835 η2 = 0.001 | F(1,43) = 4.5 p = 0.040 η2 = 0.094 | F(1,43) = 0.35 p = 0.558 η2 = 0.008 |
Night | 1.4 (2.3) | 0.9 (2.2) | 0.3 (0.3) | 0.2 (0.4) |
Driving on a narrow lane along a road repair
DWELL[%](SD) | DURATION[s](SD) | ||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|
Young | Old | Age | Light | Age x light | Young | Old | Age | Light | Age x light | ||
Street
| Day | 48.4 (11.0) | 54.4 (11.9) | F(1,43) = 1.3 p = 0.259 η2 = 0.030 | F(1,43) = 3.5 p = 0.067 η2 = 0.076 | F(1,43) = 1.5 p = 0.230 η2 = 0.033 | 1.1 (0.4) | 1.4 (0.4) | F(1,43) = 3.0 p = 0.089 η2 = 0.066 | F(1,43) = 2.5 p = 0.124 η2 = 0.054 | F(1,43) = 1.3 p = 0.262 η2 = 0.029 |
Night | 47.2 (12.6) | 48.7 (14.5) | 1.3 (0.4) | 1.4 (0.6) | |||||||
Road signs
| Day | 6.8 (4.0) | 4.9 (3.7) | F(1,43) = 3.4 p = 0.069 η2 = 0.075 | F(1,43) = 0.1 p = 0.806 η2 = 0.001 | F(1,43) = 0.1 p = 0.819 η2 = 0.001 | 1.4 (0.6) | 0.8 (0.5) | F(1,40) = 3.0 p = 0.092 η2 = 0.070 | F(1,40) = 0.2 p = 0.678 η2 = 0.004 | F(1,40) = 2.8 p = 0.100 η2 = 0.066 |
Night | 6.4 (4.8) | 4.9 (4.4) | 1.2 (0.7) | 1.1 (0.9) | |||||||
Road repair
| Day | 22.2 (6.7) | 21.1 (9.0) | F(1,43) = 0.7 p = 0.409 η2 = 0.016 | F(1,43) = 14.7 p < 0.001 η2 = 0.255 | F(1,43) = 2.8 p = 0.099 η2 = 0.062 | 0.8 (0.2) | 0.9 (0.2) | F(1,43) = 1.8 p = 0.192 η2 = 0.029 | F(1,43) = 7.8 p = 0.008 η2 = 0.606 | F(1,43) = 0.3 p = 0.606 η2 = 0.006 |
Night | 26.1 (10.4) | 31.2 (13.6) | 1.0 (0.2) | 1.1 (0.7) | |||||||
Environment
| Day | 1.1 (2.4) | 0.4 (0.7) | F(1,43) = 0.1 p = 0.828 η2 = 0.001 | F(1,43) = 0.0 p = 0.860 η2 = 0.001 | F(1,43) = 1.8 p = 0.191 η2 = 0.039 | 0.3 (0.3) | 0.2 (0.3) | F(1,41) = 0.0 p = 0.932 η2 = 0.000 | F(1,41) = 3.2 p = 0.080 η2 = 0.069 | F(1,41) = 1.3 p = 0.267 η2 = 0.029 |
Night | 0.4 (1.1) | 1.4 (5.4) | 0.1 (0.2) | 0.2 (0.4) | |||||||
Rear
-view mirror
| Day | 3.6 (2.8) | 1.4 (2.0) | F(1,43) = 13.4 p = 0.001 η2 = 0.237 | F(1,43) = 3.4 p = 0.074 η2 = 0.072 | F(1,43) = 0.8 p = 0.387 η2 = 0.017 | 0.7 (0.3) | 0.4 (0.4) | F(1,43) = 7.3 p = 0.010 η2 = 0.145 | F(1,43) = 2.6 p = 0.116 η2 = 0.056 | F(1,43) = 1.5 p = 0.224 η2 = 0.034 |
Night | 2.5 (2.0) | 1.0 (1.8) | 0.5 (0.2) | 0.4 (0.4) | |||||||
Side mirror left
| Day | 2.0 (1.8) | 1.3 (1.5) | F(1,43) = 3.4 p = 0.071 η2 = 0.074 | F(1,43) = 10.3 p = 0.003 η2 = 0.193 | F(1,43) = 0.1 p = 0.721 η2 = 0.003 | 0.5 (0.3) | 0.5 (0.5) | F(1,43) = 0.6 p = 0.460 η2 = 0.013 | F(1,43) = 0.8 p = 0.371 η2 = 0.019 | F(1,43) = 5.1 p = 0.029 η2 = 0.106 |
Night | 1.3 (1.2) | 0.7 (1.0) | 0.4 (0.3) | 0.3 (0.4) | |||||||
Side mirror right
| Day | 0.3 (0.6) | 0.3 (0.6) | F(1,43) = 1.7 p = 0.201 η2 = 0.038 | F(1,43) = 0.7 p = 0.403 η2 = 0.016 | F(1,43) = 2.6 p = 0.114 η2 = 0.057 | 0.2 (0.3) | 0.2 (0.4) | F(1,43) = 1.1 p = 0.304 η2 = 0.025 | F(1,43) = 1.7 p = 0.206 η2 = 0.037 | F(1,43) = 2.4 p = 0.145 η2 = 0.049 |
Night | 0.4 (0.7) | 0.0 (0.1) | 0.2 (0.3) | 0.0 (0.1) |
Overtaking an incoming car and car ahead
DWELL[%](SD) | DURATION[s](SD) | ||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|
Young | Old | Age | Light | Age x Light | Young | Old | Age | Light | Age x Light | ||
Street
| Day | 32.7 (7.1) | 33.9 (7.1) | F(1,43) = 0.6 p = 0.447 η2 = 0.000 | F(1,43) = 2.9 p = 0.098 η2 = 0.062 | F(1,43) = 4.3 p = 0.044 η2 = 0.091 | 1.0 (0.3) | 1.1 (0.3) | F(1,43) = 0.9 p = 0.360 η2 = 0.019 | F(1,43) = 3.3 p = 0.077 η2 = 0.071 | F(1,43) = 2.0 p = 0.169 η2 = 0.044 |
Night | 33.3 (10.3) | 28.6 (10.8) | 1.2 (0.3) | 1.2 (0.4) | |||||||
Road signs
| Day | 0.4 (0.7) | 0.2 (0.4) | F(1,43) = 0.2 p = 0.632 η2 = 0.005 | F(1,43) = 0.0 p = 0.908 η2 = 0.000 | F(1,43) = 4.0 p = 0.052 η2 = 0.085 | 0.3 (0.4) | 0.2 (0.4) | F(1,40) = 0.0 p = 0.938 η2 = 0.000 | F(1,40) = 1.0 p = 0.321 η2 = 0.025 | F(1,40) = 2.1 p = 0.160 η2 = 0.049 |
Night | 0.2 (0.5) | 0.4 (0.8) | 0.2 (0.5) | 0.4 (0.7) | |||||||
Car ahead
| Day | 20.1 (5.7) | 23.2 (5.0) | F(1,43) = 7.1 p = 0.011 η2 = 0.000 | F(1,43) = 60.3 p < 0.001 η2 = 0.584 | F(1,43) = 1.0 p = 0.332 η2 = 0.022 | 0.9 (0.3) | 1.1 (0.2) | F(1,43) = 8.8 p = 0.005 η2 = 0.170 | F(1,43) = 45.7 p < 0.001 η2 = 0.515 | F(1,43) = 4.4 p = 0.042 η2 = 0.093 |
Night | 28.8 (6.2) | 34.5 (10.3) | 1.3 (0.4) | 1.7 (0.7) | |||||||
Incoming car
| Day | 17.0 (4.6) | 16.3 (5.6) | F(1,43) = 2.5 p = 0.124 η2 = 0.054 | F(1,43) = 0.2 p = 0.651 η2 = 0.005 | F(1,43) = 4.9 p = 0.032 η2 = 0.102 | 2.0 (1.0) | 2.6 (1.3) | F(1,42) = 4.2 p = 0.048 η2 = 0.190 | F(1,42) = 0.2 p = 0.670 η2 = 0.004 | F(1,42) = 0.0 p = 0.951 η2 = 0.000 |
Night | 14.7 (5.1) | 19.7 (9.2) | 2.1 (0.8) | 2.7 (1.5) | |||||||
Environment
| Day | 3.2 (2.2) | 2.2 (2.2) | F(1,43) = 2.1 p = 0.153 η2 = 0.047 | F(1,43) = 9.1 p = 0.004 η2 = 0.174 | F(1,43) = 0.8 p = 0.371 η2 = 0.019 | 0.7 (0.3) | 0.5 (0.3) | F(1,41) = 0.9 p = 0.337 η2 = 0.022 | F(1,41) = 0.6 p = 0.459 η2 = 0.013 | F(1,41) = 1.7 p = 0.195 η2 = 0.041 |
Night | 1.7 (2.0) | 1.4 (1.2) | 0.5 (0.4) | 0.5 (0.3) | |||||||
Rear
-view mirror
| Day | 6.3 (3.6) | 5.4 (3.2) | F(1,43) = 3.6 p = 0.061 η2 = 0.079 | F(1,43) = 130.1 p < 0.001 η2 = 0.752 | F(1,43) = 3.7 p = 0.061 η2 = 0.079 | 0.6 (0.3) | 0.7 (0.2) | F(1,43) = 0.0 p = 0.972 η2 = 0.000 | F(1,43) = 4.1 p = 0.050 η2 = 0.086 | F(1,43) = 4.9 p = 0.033 η2 = 0.101 |
Night | 4.6 (3.2) | 2.3 (2.0) | 0.6 (0.2) | 0.6 (0.3) | |||||||
Side mirror left
| Day | 2.5 (1.7) | 2.6 (1.6) | F(1,43) = 0.8 p = 0.371 η2 = 0.019 | F(1,43) = 9.9 p = 0.003 η2 = 0.187 | F(1,43) = 5.3 p = 0.026 η2 = 0.003 | 0.7 (0.3) | 0.7 (0.3) | F(1,43) = 0.8 p = 0.372 η2 = 0.019 | F(1,43) = 3.8 p = 0.057 η2 = 0.082 | F(1,43) = 0.0 p = 0.973 η2 = 0.067 |
Night | 2.4 (1.5) | 1.5 (1.4) | 0.6 (0.3) | 0.6 (0.3) | |||||||
Side mirror right
| Day | 0.5 (1.1) | 0.5 (0.8) | F(1,43) = 0.4 p = 0.536 η2 = 0.006 | F(1,43) = 1.9 p = 0.171 η2 = 0.043 | F(1,43) = 0.8 p = 0.376 η2 = 0.018 | 0.2 (0.4) | 0.3 (0.4) | F(1,43) = 0.0 p = 0.987 η2 = 0.000 | F(1,43) = 1.35 p = 0.251 η2 = 0.030 | F(1,43) = 0.4 p = 0.530 η2 = 0.009 |
Night | 0.4 (0.8) | 0.2 (0.5) | 0.2 (0.3) | 0.2 (0.4) |
Avoiding collision with a parked car
DWELL[%](SD) | DURATION[s](SD) | ||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|
Young | Old | Age | Light | Age x light | Young | Old | Age | Light | Age x light | ||
Street
| Day | 26.3 (11.9) | 30.5 (15.6) | F(1,43) = 0.0 p = 0.901 η2 = 0.000 | F(1,43) = 3.1 p = 0.085 η2 = 0.067 | F(1,43) = 2.4 p = 0.125 η2 = 0.054 | 1.0 (0.8) | 1.3 (0.7) | F(1,39) = 0.2 p = 0.638 η2 = 0.006 | F(1,39) = 5.3 p = 0.027 η2 = 0.119 | F(1,39) = 3.7 p = 0.063 η2 = 0.086 |
Night | 25.8 (13.1) | 22.0 (12.6) | 1.0 (0.6) | 0.8 (0.4) | |||||||
Road signs
| Day | 0.0 (0.0) | 0.0 (0.0) | F(1,43) = 0.6 p = 0.427 η2 = 0.015 | F(1,43) = 38.4 p < 0.001 η2 = 0.472 | F(1,43) = 0.6 p = 0.427 η2 = 0.015 | 0.0 (0.0) | 0.0 (0.0) | F(1,37) = 1.3 p = 0.268 η2 = 0.033 | F(1,37) = 36.2 p < 0.001 η2 = 0.494 | F(1,37) = 1.3 p = 0.268 η2 = 0.033 |
Night | 6.7 (6.3) | 5.1 (6.5) | 0.6 (0.6) | 0.4 (0.5) | |||||||
Parked car
| Day | 50.4 (11.3) | 51.6 (17.7) | F(1,43) = 4.6 p = 0.039 η2 = 0.096 | F(1,43) = 0.3 p = 0.573 η2 = 0.007 | F(1,43) = 6.6 p = 0.014 η2 = 0.132 | 1.6 (0.7) | 1.6 (0.6) | F(1,42) = 6.4 p = 0.014 η2 = 0.136 | F(1,42) = 12.9 p = 0.001 η2 = 0.234 | F(1,42) = 9.32 p = 0.004 η2 = 0.182 |
Night | 42.5 (12.1) | 56.6 (17.1) | 1.6 (0.4) | 2.6 (1.4) | |||||||
Environment
| Day | 1.5 (2.5) | 0.9 (3.0) | F(1,43) = 0.3 p = 0.590 η2 = 0.007 | F(1,43) = 2.7 p = 0.108 η2 = 0.059 | F(1,43) = 0.5 p = 0.472 η2 = 0.012 | 0.2 (0.2) | 0.1 (0.2) | F(1,43) = 0.8 p = 0.380 η2 = 0.018 | F(1,43) = 1.1 p = 0.312 η2 = 0.024 | F(1,43) = 1.1 p = 0.312 η2 = 0.024 |
Night | 0.5 (1.6) | 0.5 (1.8) | 0.1 (0.2) | 0.1 (0.2) | |||||||
Rear
-view mirror
| Day | 4.2 (4.5) | 2.3 (3.8) | F(1,43) = 3.4 p = 0.071 η2 = 0.074 | F(1,43) = 0.6 p = 0.437 η2 = 0.014 | F(1,43) = 0.1 p = 0.825 η2 = 0.001 | 0.3 (0.3) | 0.2 (0.4) | F(1,43) = 1.7 p = 0.199 η2 = 0.042 | F(1,43) = 1.1 p = 0.299 η2 = 0.028 | F(1,43) = 0.3 p = 0.616 η2 = 0.007 |
Night | 3.5 (4.3) | 1.9 (3.3) | 0.4 (0.5) | 0.3 (0.4) | |||||||
Side mirror left
| Day | 3.9 (3.9) | 3.0 (4.3) | F(1,43) = 1.7 p = 0.201 η2 = 0.038 | F(1,43) = 2.1 p = 0.157 η2 = 0.046 | F(1,43) = 0.1 p = 0.706 η2 = 0.003 | 0.4 (0.4) | 0.3 (0.4) | F(1,42) = 2.1 p = 0.159 η2 = 0.047 | F(1,42) = 0.3 p = 0.569 η2 = 0.008 | F(1,42) = 3.0 p = 0.091 η2 = 0.067 |
Night | 3.2 (2.0) | 1.9 (3.4) | 0.5 (0.4) | 0.3 (0.4) | |||||||
Side mirror right
| Day | 0.7 (1.9) | 0.0 (0.0) | F(1,43) = 5.7 p = 0.022 η2 = 0.116 | F(1,43) = 0.0 p = 0.889 η2 = 0.000 | F(1,43) = 0.3 p = 0.573 η2 = 0.007 | 0.1 (0.3) | 0.0 (0.0) | F(1,43) = 5.8 p = 0.021 η2 = 0.118 | F(1,43) = 0.2 p = 0.642 η2 = 0.005 | F(1,43) = 0.0 p = 0.939 η2 = 0.000 |
Night | 0.6 (1.2) | 0.1 (0.5) | 0.1 (0.3) | 0.0 (0.1) |
Driving performance
Young(N = 28) | Old(N = 25) | Significance | ||||
---|---|---|---|---|---|---|
Age | Light | Light x Age | ||||
Driving speed [km/h] (SD)
| Day | 82.0 (2.4) | 78.5 (3.1) | F(1,51) = 18.8 p < 0.001 η2 = 0.269 | F(1,51) = 2.1 p = 0.162 η2 = 0.038 | F(1,51) = 1.2 p = 0.278 η2 = 0.023 |
Night | 82.1 (2.4) | 79.5 (3.8) | ||||
Driving speed variance [km/h] (SD)
| Day | 2.4 (2.5) | 12.7 (12.5) | F(1,51) = 30.4 p < 0.001 η2 = 0.373 | F(1,51) = 2.8 p = 0.099 η2 = 0.052 | F(1,51) = 1.2 p = 0.279 η2 = 0.023 |
Night | 4.0 (5.4) | 20.0 (26.4) | ||||
Lane-keeping [degree] (SD)
| Day | 0.4 (0.2) | 0.7 (0.3) | F(1,51) = 19.2 p < 0.001 η2 = 0.274 | F(1,51) = 10.4 p = 0.002 η2 = 0.169 | F(1,51) = 1.5 p = 0.229 η2 = 0.028 |
Night | 0.5 (0.3) | 0.9 (0.4) | ||||
Lane-keeping variance [degree] (SD)
| Day | 0.2 (0.1) | 0.6 (0.7) | F(1,51) = 13.4 p = 0.001 η2 = 0.209 | F(1,51) = 0.8 p = 0.384 η2 = 0.015 | F(1,51) = 0.1 p = 0.705 η2 = 0.003 |
Night | 0.2 (0.2) | 0.7 (1.1) |