PERFORMANCE-BASED DRIVING EVALUATION OF THE ELDERLY DRIVER - SAFETY, RELIABILITY, AND VALIDITY

Background. Our driving population is aging and faces increased risk f or injury and death from motor vehicle crashes. Clinicians are often a sked to judge the driving safety of their patients without adequate gu idelines. This article describes the development of a systematic perfo rmance-based road test for measuring driving skills of elderly drivers and its correlation with cognitive measures. Methods. This was a pros pective, masked, observational study in which a driving instructor's g lobal scores (''criterion standard'') and cognitive test scores were c orrelated with research driving scores created by two independent rese arch raters sitting in the back seat of the car during each driving te st. A convenience sample of 30 licensed drivers with a broad range of cognitive skills, over age 60, were studied on a closed course and in traffic. Results. Statistically significant correlations were observed between the ''criterion standard'' and closed course scores (r = .35, p < .05) and between the ''criterion standard'' and in-traffic scores (r = .64, p < .01). Significant correlations were obtained between in -traffic and cognitive test scores, e.g., Mini-Mental State Exam (r = .72, p < .01). Inter-rater reliability on the closed course was .84 an d on the in-traffic component was .74. Internal consistency for the cl osed course was .78 and for in-traffic was .89. Conclusion. This study documented the safety, reliability, and validity of a systematic road test for elderly drivers with a range of cognitive skills. Larger stu dies are needed to determine the cognitive factors that independently predict driving performance.