Table of Contents
International Journal of Vehicular Technology
Volume 2013, Article ID 705086, 12 pages
Research Article

Evaluation of a Navigation Radio Using the Think-Aloud Method

1Driver Interface Group, University of Michigan Transportation Research Institute, 2901 Baxter Road, Ann Arbor, MI 48109-2150, USA
2Advanced Vehicle Safety and Dynamics Research Office, Korea Automobile Testing and Research Institute, 200 Samjon-ro, Songsan-myeon, Hwaseong-si, Gyeonggi-do 445-871, Republic of Korea

Received 10 October 2012; Accepted 26 December 2012

Academic Editor: Motoyuki Akamatsu

Copyright © 2013 Paul A. Green and Jin-Seop Park. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


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.