Visual attention problems as a predictor of vehicle crashes in older drivers.

PURPOSE: To identify visual factors that are significantly associated with increased vehicle crashes in older drivers. METHODS: Several aspects of vision and visual information processing were assessed in 294 drivers aged 55 to 90 years. The sample was stratified with respect to age and crash frequency during the 5-year period before the test date. Variables assessed included eye health status, visual sensory function, the size of the useful field of view, and cognitive status. Crash data were obtained from state records. RESULTS: The size of the useful field of view, a test of visual attention, had high sensitivity (89%) and specificity (81%) in predicting which older drivers had a history of crash problems. This level of predictability is unprecedented in research on crash risk in older drivers. Older adults with substantial shrinkage in the useful field of view were six times more likely to have incurred one or more crashes in the previous 5-year period. Eye health status, visual sensory function, cognitive status, and chronological age were significantly correlated with crashes, but were relatively poor at discriminating between crash-involved versus crash-free drivers. CONCLUSIONS: This study suggests that policies that restrict driving privileges based solely on age or on common stereotypes of age-related declines in vision and cognition are scientifically unfounded. With the identification of a visual attention measure highly predictive of crash problems in the elderly, this study points to a way in which the suitability of licensure in the older adult population could be based on objective, performance-based criteria.

Visual/cognitive correlates of vehicle accidents in older drivers.

Older drivers have more accidents per miles driven than any other age group and tend to have significant impairments in their visual function, which could interfere with driving. Previous research has largely failed to document a link between vision and driving in the elderly. We have taken a comprehensive approach by examining how accident frequency in older drivers relates to the visual/cognitive system at a number of levels: ophthalmological disease, visual function, visual attention, and cognitive function. The best predictor of accident frequency as recorded by the state was a model incorporating measures of early visual attention and mental status, which together accounted for 20% of the variance, a much stronger model than in earlier studies. Those older drivers with a visual attentional disorder or with poor scores on a mental status test had 3-4 times more accidents (of any type) and 15 times more intersection accidents than those without these problems.

Motivational determinants of illicit drug use: an assessment of underlying dimensions and their relationship to behavior.

Principal components analysis was used to delineate motivational patterns associated with illicit drug use in a population of U.S. Navy enlisted men (n = 867) undergoing drug rehabilitation. Patients indicated which of 31 reasons for drug use were associated with various drugs. Four components emerged from this analysis, labeled Insight-Seeking, Therapeutic Needs, Sentience, and Pleasure-Seeking. Higher order factor analysis revealed the presence of a general factor, labeled General Sensation-Seeking. Multiple regression procedures were used to relate the derived dimensions to actual drug use behavior. The significant relationships observed among the factor analytic patterns in predicting overall drug involvement were shown to lead to increased explanation concerning interrelationships among personality needs and social resources. The findings suggested a number of hypotheses pertaining to increased understanding of motivational patterns underlying initiation and continuation of illicit drug use.