The use of think-aloud evaluation methods in design

This paper reports on two studies in which teams of two or three trainee designers evaluated a user interface by observing a user working through some set tasks. These users were instructed to think aloud as they worked. The instruction received by the designers took the form of a brief how-to-do-it manual. Study 1 demonstrates that this method is effective. Study 2 found that more problems were detected by the designers of the system than other groups. Also, designers cannot predict the problems users will experience in advance of user testing.