Performance-based measurements among elderly drivers and nondrivers.

Although driving is an important ability for maintaining independence in the later years, clinical factors that determine driving status are unknown. Aged male veterans (mean age, 70 years) were recruited from an outpatient clinic (N = 143), including 77 frequent drivers, 41 infrequent drivers, and 25 who drove rarely or not at all. There were 116 (84%) who completed a comprehensive performance-based assessment. There were no significant differences between the three groups in age, formal cognitive testing, or prevalence of stroke history. However, there were significant differences in grip strength, reaction time, static visual acuity, dynamic visual acuity, and peripheral vision. Using stepwise ordinal logistic regression, dynamic visual acuity, nondominant hand grip strength, and total horizontal peripheral visual field were significantly associated with driving frequency (P less than .05), and together explained approximately 45% of the variance. Subtle motor and visual deficits that can be detected by a performance-based assessment may play an important role in determining driving frequency in the elderly.