Evaluating the Effectiveness of Think-Aloud Protocol and Impact Analysis on the Usability Testing for Healthcare Professionals

Abstract

For developing medical devices with high usability, it is important to understand and specify the context of use through usability testing. In this study, we have evaluated the effectiveness of think-aloud protocol and impact analysis as usability testing methods for healthcare professionals. An endotracheal tube cuff inflator was used for usability testing. First, five nurses were required to perform a cuff pressure management task using the current equipment. Besides, the think-aloud protocol and video-recording were used during the task to investigate usability problems of the current equipment. Next, the usability problems were classified into the order to be resolved by impact analysis. Then, a development equipment was prototyped and designed. Finally, ten nurses were required to perform the cuff pressure management task using the current equipment and the development equipment. As a result, the time required for the task in the case of the development equipment was shorter than that in case of current equipment. Furthermore, the subjective evaluation in the case of prototype equipment was higher than that in the case of development equipment. These data suggested that the usability of the development equipment was higher than that of the current equipment. From the above, it was considered that the combination of the think-aloud protocol and the impact analysis was effective for usability improvement of medical devices.