The effect of task assignments and instruction types on remote asynchronous usability testing.

Remote asynchronous usability testing involves users directly in reporting usability problems. Most studies of this approach employ predefined tasks to ensure that users experience specific aspects of the system, whereas other studies use no task assignments. Yet the effect of using predefined tasks is still to be uncovered. There is also limited research on instructions for users in identifying usability problems. This paper reports from a comparative study of the effect of task assignments and instruction types on the problems identified in remote asynchronous usability testing of a website for information retrieval, involving 53 prospective users. The results show that users solving predefined tasks identified significantly more usability problems with a significantly higher level of agreement than those working on their own authentic tasks. Moreover, users that were instructed by means of examples of usability problems identified significantly more usability problems than those who received a conceptual definition of usability problems.