Evaluation of a Navigation Radio Using the Think-Aloud Method

Abstract

In this experiment, 13 licensed drivers performed 20 tasks with a prototype navigation radio. Subjects completed such tasks as entering a street address, selecting a preset radio station, and tuning to an XM station while “thinking aloud” to identify problems with operating the prototype interface. Overall, subjects identified 64 unique problems with the interface; 17 specific problems were encountered by more than half of the subjects. Problems are related to inconsistent music interfaces, limitations to destination entry methods, icons that were not understood, the lack of functional grouping, and similar looking buttons and displays, among others. An important project focus was getting the findings to the developers quickly. Having a scribe to code interactions in real time helped as well as directed observations of test sessions by representatives of the developers. Other researchers are encouraged to use this method to examine automotive interfaces as a complement to traditional usability testing.