Concurrent Think-aloud Method (CTA)
During usability tests, participants are asked to narrate their thoughts. Applying the concurrent think-aloud method (CTA), the verbalization happens simultaneously while participants are interacting with the test product. This enables the moderator to develop a better understanding of which contents the participants are engaging with, what they are thinking, whether questions arise or what participants are feeling. This method is very well suited for identifying usability problems. Moreover, it also is time saving, as it is applied while participants are completing the test tasks.
The concurrent think-aloudmethod has also been criticized: experiments have shown that because of the simultaneous verbalization of thoughts, the completion of test tasks sometimes takes longer. CTA can also have an effect on the success of task completion. Because they are thinking aloud, some participants reflect more on what they are doing and are able to better organize their thoughts.
Also view: Retrospective Think-aloud