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As mentioned in How many participants?, the tree you’re testing may serve more than one user group. As discussed in Chapter ~, Writing Tasks, Different tasks for different user groups in Chapter 7, there are two basic methods to testing multiple types of users:
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To recruit for this test, you would typically identify qualified participants first, then point them to the study. In other words, the qualifying step would be done before they start the test. For more on this, see ~“Screening Screening for specific participants” participants later in this chapter.
Identifying in the same test
If you’re targeting several user groups with the same test, you first need to make sure that each user group can reasonably perform the tasks you’ve set. For more on this, see Chapter ~, Writing Tasks Different tasks for different user groups in Chapter 7.
Because they’re all doing the same test, you need a way to identify each participant’s user group. This is usually done by adding a survey question to the test. Later, when you’re analyzing the results, you can filter them by this question to compare between the user groups.
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For more on how to filter results by user group, see Chapter ~, Analyzing Results Analyzing by user group or other criteria in Chapter 12.
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Next: Using web ads