Applicable stages: design, code, test, and deployment.
Personnel needed for the evaluation: Usability experts: 1 Software developers: 0 Users: 4	Usability issues covered: Effectiveness: Yes Efficiency: No Satisfaction: Yes
Can be conducted remotely: No	Can obtain quantitative data: No

 Overview

During a usability test, besides letting the test users to verbalize their thoughts as in the thinking aloud protocol, the testers prompt them by asking direct questions about the product, in order to understand their mental model of the system and the tasks, and where they have trouble in understanding and using the system. This is a more natural way than the thinking-aloud method in letting the test user to verbalize their thoughts.

Providing the test users with the product to be tested (or a prototype of its interface) and a set of tasks to perform. Ask the participants to perform the tasks using the product, and explain what they're thinking about while working with the product's interface. Also ask them pointed, direct questions about the product; for example, "How would you send the email message?" Their response, either in terms of the product being tested or in other products from their past experience, will provide insights into their mental model of the product.