Two participants perform an activity and help each other as they would naturally. They are encouraged to explain what they are thinking about while working on the tasks.
1. Select and recruit participants that are representative of the end user.
2. Prepare the testing session, schedule tests so participants are in pairs, prepare prototype and test materials, set up and test video/ audio recording, design the scenario and tasks for the user test.
3. As a moderator, explain to users that the idea is to test the system. Ask them to perform the tasks and mention that the thought process is important and that they should talk aloud explaining what they are doing and why.
4. As notetaker, make sure you take notes and facilitate setting up/updating the test when needed.
5. Analyze the video recordings.
In the testing phases of a project, this can be done with sketchy designs and/or high fidelity prototypes.
Having two participants that test the system, allows to gain different viewpoints on the same design.
If the participants have trouble with a specific task, avoid helping them, let them gure it out themselves.
An overview of what works and what doesn’t in the design.
Improve the design where it had problems during the test.
KEMP, J. A. M.; VAN GELDEREN, T. Co-discovery exploration: an informal method for the iterative design of consumer products. Usability evaluation in industry, 1996, 139-146. SIAU, Keng. Evaluating the usability of a group support system using co-discovery. The Journal of Computer Information Systems, 2003, 44.2: 17.