Assessment of older driver understanding of certain traffic control devices in Texas

Abstract

The purpose of this research was to assess older Texas drivers on their understanding of nine traffic control devices and identify the devices that are misunderstood by people 65 years and older. Additionally, older driver education programs were to be reviewed for traffic control device inclusion so that improvements could be recommended. To accomplish these objectives, a total of 200 subjects were surveyed in four Texas cities. Participants were shown graphical representations of each device and asked questions about various device aspects. The traffic control devices in this survey included five traffic control signal indications, two warning signs, one school sign, and one type of marking. The chosen devices have been shown to be problematic with the general population and have serious consequences if misunderstood and inappropriate driving actions are taken. Correct response rates were determined for each device aspect in question. Comprehension levels greater than 85 percent indicated an adequate device understanding, while comprehension levels below 85 percent suggested traffic control device aspects that are not well understood by older drivers. In general, the overall comprehension level was found to be less than desirable, especially for the complexities of traffic control signals and signs. Older drivers appear to have similar comprehension levels as that of the general Texas public. Recommendations vary for each device. Left-turn displays consisting of a circular red and a green arrow should no longer be used. A CROSSROAD TRAFFIC MUST STOP sign should be installed at all intersections with both yellow and red flashing intersection beacons. Three signs should be redesigned: Divided Highway Ends, Slow Down on Wet Road, and School Advance. Additional research should be conducted on School Advance signs with the new strong yellow-green legend color. Emphasis of right-of-way for circular green with green arrow displays and flashing intersection beacons is needed in older driver education programs and the licensing renewal process. Lastly, no action is needed for two-way left turn lane pavement markings.