A Comparative Analysis of Usability Evaluation Methods on Their Versatility in the Face of Diversified User Input Methods

Every command consists of an action and an object, suggesting that a usability problem can occur whenever the user is unable to identify an appropriate action and/or the object associated with his/her current goal. The recent shift from mouse-based to touch-based interaction demands that any usability evaluation method be sensitive to not only object-related but also action-related usability problems. This study involved a total of 32 participants, four kinds of tasks differing in the difficulty of identifying objects and executing actions, and four qualitative methods of usability evaluation. Analyses of sets of observation data with concurrent and retrospective protocol by the same participant and interpretive protocol by a new participant indicate that while the oral instruction method seems least appropriate, the newly-devised narration method seems to have better prospects than the observation and the think aloud method for the usability evaluation of touch-based interaction.