Error specific restrictions for older drivers: promoting continued independence and public safety

Abstract

Objectives: To describe a population of older drivers with driving restrictions, their most common restrictions, and to compare restricted drivers to their safe and unsafe counterparts. Safe drivers are those who do not commit hazardous errors or traffic violations. Unsafe drivers are those who commit hazardous errors and/or traffic violations that place them in hazardous situations. Restricted drivers are those who have committed traffic or rule violations only under certain driving conditions.

Design: A retrospective, cross-sectional study with mixed methodology.

Setting: A clinical driving evaluation program within an academic geriatrics department.

Participants: Drivers age 60+ (N=108) referred for clinical driving evaluation and who consented to allow their data to be used for research purposes.

Intervention: Drivers performing at an intermediate level driving fitness were issued error specific driving restrictions.

Measurement: Driving evaluation included clock drawing test (CDT), mini-mental status exam (MMSE), Trailmaking, geriatric depression scale (GDS), and simulated driving.

Results: The three most common restrictions were limited driving distance (N=8), limited driving time (N=8), and daytime only driving (N=8). Safe, restricted, and unsafe drivers significantly differed on MMSE (F[2,104]=10.75, p<0.001), Trailmaking Part B (F[2,76]=9.96, p<0.001), CDT (F[2,98]=29.88, p<0.001), and total number of hazardous errors (F[2,97]=39.06, p<0.001). Tukey's test indicated safe and restricted drivers scored significantly better than unsafe drivers on MMSE (safe: p<0.001; restricted: p=0.008), CDT (p<0.001), and hazardous errors (p<0.001). Restricted and unsafe drivers required significantly more time to complete Trailmaking B than safe drivers (p=0.004).

Conclusion: Preliminary data indicate restricted drivers perform more like safe than unsafe drivers. Driving simulation is instrumental in discerning error specific limitations and categorizing patients as conditionally safe. This clinical evaluation pilots an effective alternative to premature driving cessation.