Speedometer-reading performance of senior drivers with cognitive impairment: a comparison of analogue and digital...

With the deterioration of cognitive functions, the capability to obtain information with speed, one of the essential elements needed to perform safe driving, may be impacted. We aimed to compare the legibility of analogue and digital speedometers for senior drivers with cognitive impairment, and examined the demographic, cognitive, and driving-related variables that predict their speedometer-reading performance.

A total of 50 senior drivers with cognitive impairment were investigated and asked to complete an office-based speedometer-reading test using an iPad. Two general types of speedometers (analogue and digital) were tested in this study.

The age of the participants ranged from 61 to 92 years (mean (SD), 79.10 (6.973)), and 29 were male. The mean (SD) score of the Mini-Mental State Examination was 22.48 (6.089). The median (Q_L , Q_U ) scores of the analogue and digital speedometer-reading tests were 4 (4, 5.25) and 6 (6), respectively. Based on the result of the Wilcoxon signed-rank test, the score of the digital speedometer-reading test was significantly higher than that of the analogue one (Z = 4.399, P < 0.001). The results of multiple linear regression analyses show that the scores of the Mini-Mental State Examination (β = 0.358, P = 0.025), and the trail-making test-A (β = -0.443, P = 0.006) predicted the digital speedometer-reading performance, and they together explain 54.7% of the total variance.

A digital speedometer was found to be easier for absolute value reading for senior drivers with cognitive impairment, compared to an analogue speedometer. Senior drivers with subjective cognitive decline may also have impairments in obtaining the speed information through an analogue speedometer. General cognitive function and attention may influence the speed-reading performance on the digital speedometer.