Handbook of Usability Testing: How to Plan, Design, and Conduct Effective Tests, Second Edition

Chapter 7. Find and Select Participants

The selection and acquisition of participants whose background and abilities are representative of your product's intended user is a crucial element of the testing process. After all, your test results will only be valid if the people who participate are typical users of the product, or as close to that criterion as possible. If you test with the "wrong" people, it does not matter how much effort you put into the rest of the test preparation. Your results will be questionable and of limited value.

Selecting participants involves identifying and describing the relevant behavior, skills, and knowledge of the person(s) who will use your product. This description is known as the user profile of the target audience and should have been developed in the early stages of the product development. Then, once that has been determined, you must ascertain the most effective way to acquire people from this target audience to serve as participants within your constraints of time, money, resources, and so on.

Characterize Users

Now your first thought might be that the information describing the user profile should already exist and be written down somewhere within your organization, because the design and makeup of any product is supposed to be predicated on knowing the end user. While this is so in theory, experience shows that this information is rarely collected systematically or written down. Or, if it is written down, it does not quite make it to the desks ...