Summary: a) The purpose of the present study was to illustrate how driver capability could be measured based on the presence of assistance during on-road evaluation. As an objective, this study explored the potential of a new method to measure declines in driver independence (steering/braking assistance) and safety (driving cues) for driver fitness determinations. b) A study at the Adaptive Driving Program (ADP) was conducted through a medical record review of 132 clients served in 2009. Following creation of an enumerated list of unique errors committed in baseline driving sessions, follow-up analysis focused on the association between assistance during on-road evaluation and case outcomes. The analysis also involved associations between assistance and five classes of errors reported among all clients. c) Findings showed that the proposed measures of driver independence and safety were associated with 90% of clients that did not pass on-road evaluation and a majority of errors related to tracking vehicle position within a lane. Though documented assistance showed low association to four out of five classes of errors, the potential for detection of these assistedevents may be 60-80% of all errors in each class except for lane changes.
OBJECTIVESNearly all driving evaluations involve a report that either enumerates or scores performance based on errors committed under observation. The challenge of driver capability measurement relates to the complexity of the many factors which contribute to a "Swiss cheese" model of risk (Sheridan, 2008), where potentially negligible, individual errors (holes) line up undetected to allow crash risk to pass through protections and become a crash realized. In each scenario of a committed driving error, factors such as the driving maneuver, posted traffic signals and signs, road obstacles, road quality, weather conditions, presence of other road users, and pedestrians are among the many issues complicating a direct question: Is my client fit to drive based on today's demonstration of driver capability?Physicians face great difficulty when advising concerns with driving, especially when they are voiced from family members and friends who are unable to reach an agreement with the license holder (the patient). In order to ease the tension between physicians and their patients, a (Certified) Driver Rehabilitation Specialist can provide additional evidence to assist in the determination of fitness to drive. Physicians surveyed in a study (Jang et al., 2007) had reported that 75% viewed the act of reporting to present a conflict of interest in the physician-patient relationship, and 45% were not confident with the responsibility of reporting. The AMA ADReS Guidelines (Carr, 2010) define a standard for primary care physicians to assess driving related skills for patients who are known to be driving.
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PROCEEDINGS of the Seventh International Driving Symposium on Human Factors in Driver Assessment, Training, and Vehicle DesignAny recommendations for driver cessation should be based on th...