Quantitative and Qualitative Analysis of a Japanese Road Sign Recognition Task

Abstract

Occupational therapists use the Road Sign Recognition task (RSR) to assess driving capabilities. The Japanese Version of the Stroke Drivers' Screening Assessment (JSDSA), frequently used to specifically evaluate Japanese individuals' driving ability post-stroke, includes the RSR. However, the RSR in the J-SDSA utilizes signs and illustrations of overseas, making it less suitable for Japan. Therefore, this study developed an RSR using Japanese signs and actual driving photographs to investigate the relation of age, driving experience, and history of safe driving education on task difficulty. The RSR, consisting of 10 questions, was administered to 167 participants, including 62 older adults, 69 young adults, and 36 driving instructors with a driver's license. The results showed that the correct answers in the RSR were the highest in the order of instructors, young adults, and older adults. Similarly, the time required for the RSR was the shortest for instructors followed by young and older adults. The Rasch analysis indicated that the top three most difficult and easiest questions for older adults and young adults were the same. However, the questions deemed difficult or easy for instructors differed from the other two groups. This study indicated that age, driving experience, and safe driving education play important roles in RSR. The findings also highlight the necessity of understanding the examinee's background when applying the RSR to assess driving ability.