Tree testing

What it is

Tree testing is a user testing technique for determining how easy it is to find topics in a website. Tree testing uses a simplified text version of the site structure, instead of testing on the website itself.  This keeps the focus on evaluating the information structure, without the distractions of the website’s design and navigation.  Tree testing is also sometimes called reverse card sorting.

Why it’s useful

Tree testing is a useful way to test whether your groupings of information, topic labels and information structure make sense to users.  Tree testing is used to inform information architecture, menu structures and navigation for a website or online tool.

Tree testing answers  these questions:

  • Could users find items in the tree?
  • Could they find those items directly, without having to go back?
  • If they couldn't find items, where did they get lost?
  • Could they choose between topics quickly, without too much thought?
  • Which parts of the tree worked well, and which didn’t?

When to do it

Tree testing is useful in the prepare and develop phases.

How to do it

  1. Identify what you want to achieve with tree testing.
  2. Select your participants.  See: Recruiting users for some guidance around numbers.
  3. Give the participant a task to find something, e.g. “Look for information on..."
  4. Show them a list of the top-level topics.
  5. They choose a topic.
  6. Show them a list of subtopics.
  7. The particpant continues choosing topics - moving down through the tree, backtracking if necessary – until they find a topic that satisfies the task.  Or until they give up.
  8. The participant does several tasks, starting each task at the top of the tree.
  9. Once several participants have completed the test, the results are analysed for each task.