'Think-Aloud"Advantages and Disadvantages

Some participants will naturally verbalize what they are going through as they work through a usability test session. These people are gold; having a running commentary (something researchers call a "verbal protocol") from participants as they "think aloud" while they perform tasks offers many insights to why a problem exists and how someone tries to work around it Asking participants to think aloud during their sessions also reveals important clues about how they are thinking about (lie product or system they are using

and whether the way it works matches up with the way it was designed Farticipants always filter to some extent, however, so they may consciously or unconsciously leave things out as they talk. Likewise, it is impossible to know wrythmg that is going through a participants' mind during the session (it is of course likely that you don't want to know everything, just what pertains to your product, anyway). Thinking aloud can also help participants think through the design problem and form ideas for recovering While this J'n * a wa>'s vvhat they would do in real life, their doing so will giv e you ideas about how to remedy design problems.

One important reason to avoid asking participants to think aloud is significant]3re measuring ,ime 0n tasks" Thinking aloud slows performance