A method for testing the comprehension of static traffic signs

A method to test the comprehension of static traffic signs is developed. The objective is to design a method that is easy to apply that will provide information that can be used for identifying signs that drivers and pedestrians do not understand very well, developing alternatives for these poorly understood signs, and testing the understandability of these alternative signs.;A critical examination is made of previous test methods that try to assess driver or pedestrian comprehension. This information along with an examination of meanings that are misapplied to traffic signs, how signs are designed, and other material gathered from a state-of-the-art review is used to formulate an initial test method. The method proposed simulates the recall and deduction processes that take place when a driver or pedestrian attempts to understand a traffic sign. This initial method is used to test signs thought to cause comprehension problems along with candidate replacement signs. The results of the first test are used to identify deficiencies in the test method. These deficiencies are analyzed and corrected, and the test is repeated a second time. The second set of results are analyzed and a cross validation is performed to assess the validity of the method. The calculated correlation coefficients show the method to be very reliable. However, it must be pointed out that the method is somewhat dependent on the ability of the user to choose an appropriate test audience and correctly categorize the various responses given by the subjects to the open-ended questioning format and post-test debriefing.