Train participants to think aloud

When usability testing I instruct my participants to think out loud. However, despite their best effort, they would still forget to narrate their thinking time-to-time.

Think-aloud is a skill. Even if we instruct participants to think aloud they still need some training until they get into the habit.

We can remind them in many different ways.

We can ask about their thoughts directly:

• "What's on your mind?"
• "What's going on in your head?"

We can point out the fact that they stopped talking

• "You seemed to have paused for a moment..."

Or we can simply mirror their last words or actions before they went silent.

"So you clicked there and..."

I find that mirroring is the most effective way to condition participants to think aloud continuously. It reminds them of their duty, but it does so with minimal interference to their thought process. It is such a delicate nudge that participants often don't even notice that I said something. I was just holding their trail of thought for them until they were ready to pick it up again.