Organization of content is one of the biggest challenges when building a new website or improving the user experience of an existing website. Logical and intuitive organization of information is essential for creating a good user experience. However, websites and apps suffer from overlapping information categories and confusing labels fairly regularly, especially if your website has been around for a few years. If your content cannot be easily found or accessed, no matter how pretty your website or app is, it will create a poor user experience and your conversion rates will go down.

How do you validate the effectiveness of your product’s content organization? How do you ensure you have proper structuring and labeling? Fortunately, we have a fast and effective technique called tree testing, which helps you create categories and labels that make sense to your audience. Tree testing is an excellent technique for testing the information architecture of your website or app.

If you’re planning a tree test for the first time, this article is for you.

What is tree testing?

Tree testing is a powerful method in evaluating the hierarchical structure and findability of your content. You may wonder why this testing has the word tree in it. A typical website/mobile app consists of a hierarchy of categories and subcategories, all of which branch out from the homepage/home screen. This hierarchy of content visually looks like a tree. Tree testing is assessing findability within the hierarchy of a website or app and is a fast and effective technique for testing categories and labels with your audience.

How tree testing works

Tree testing is a task-based activity. Test participants are asked to find the locations of specific elements in the existing structure. You can analyze where your users would expect to find the information, and you can make improvements to your product based on this behavior.

How is tree testing different from card sorting?

Despite the fact that card sorting and tree testing share the same goal of content categorization, they each approach this goal from a different angle and are used at different times in the content strategy process. In card sorting, users are given a list of content items and asked to group and label them. Card sorting is an excellent technique for understanding how your audience thinks. However, it won’t be very helpful for creating an exact categorization scheme you should follow. Why? Because test participants create their own categories and group items within those categories. It’s not always possible to design the scheme that exactly aligns with the categories proposed by users.

cards stacked on top of each other compared to cards arraigned in two rows.
Closed card sorting. Image by IDF.

Tree testing asks testers to work with a predefined structure of categories and highlight where they believe an item is most likely to be located. That’s why tree testing is often called “reverse” card sorting. Tree testing is incredibly useful as a follow-up to card sorting because it helps to evaluate a hierarchy according to how it performs in a real-world scenario (when users try to complete a specific task such as finding content on a website or in the app).

What to remember when conducting tree testing

Tree testing preceded navigation design and helps you to structure information logically.  Unlike traditional usability testing, tree testing doesn’t require interaction with the actual products; instead, a simplified text version of the product’s structure is used. To conduct a tree test, you need to prepare two things: a) the hierarchy and b) the tasks or instructions which explain to test participants what they should attempt to find. The goal of tree testing is to find an answer to the question, “Can users find what they are looking for?”

Conduct tree testing prior to building a prototype

Tree testing is normally conducted early on in the design process. The perfect moment for tree testing is the moment when you define a structure of your website/app in its most basic form (i.e. sketches or lo-fi wireframes) and are ready to design individual pages.

Have a complete tree

Your tree should be a complete list of all your main content categories and their subcategories. Even if you are interested in testing only a specific section of the tree, excluding the other sections is risky because it assumes that users are familiar with your product field and will know the relationship between sections.

a spreadsheet organizing a website into different columns
A high-level organization of a website. Image by nngroup.

Prepare a set of tasks

The tasks you ask test participants to complete are just as important as the tree itself. Each task should test a category label by asking the user to find something contained within that category.

As an example, here is the task for evaluating the Brands category on the cosmetic eCommerce website tree.

3 different boxes for a menu, brands, and american crew with arrows connecting each to show the website navigation process.
Tree testing task. Image by loop11.

Here are a few essential things to remember when preparing tasks:

  • Decide which categories and labels you want to target. Ideally, you should include tasks that target key website goals and user tasks, such as finding the most critical information.
  • Have the right answer for each task. For each task you prepare, you should also define the correct answer(s), corresponding to where the information is actually located within the tree. This information allows the testing tool to calculate success rates for each task automatically.
  • Prevent priming. When writing the task instructions, avoid using terms or asking questions that give away the answers.

Short and effective test sessions

Tree-testing shouldn’t take longer than 20 minutes. Don’t ask test participants to complete more than ten tasks. The more test participants interact with the hierarchy, the more familiar the structure becomes so they will remember where they’ve seen things before, and this will hurt outcomes from the sessions.

Use special tools for tree testing

While it’s possible to conduct tree testing using a pen and paper, it’s recommended to use online services designed specifically for tree testing because they are very helpful in processing and analyzing results. Userzoom and Treejack are both good options for conducting tree testing.

web page lists with the connecting pages arraigned in a vertical row.
Visualizations make it simpler to analyze tree test results. The results of tree testing in Userzoom.

Conduct a few pilot runs

It’s possible to conduct both moderated and unmoderated tree testing. Many companies prefer to conduct remote, unmoderated studies because such studies are less expensive. Test participants receive assignments and complete them on their computers in their own chosen environment. But this format has one major flaw – the remote unmoderated format isn’t perfect for capturing the full context of user behavior.  It’s recommended to conduct at least a few moderated pilot sessions before running bulk testing. This approach will help you mitigate the risk of missing important details. You will be able to adjust the instructions and get more valuable insights from the sessions. 

If you run a moderated in-house tree testing session, you should ask participants to talk through their rationale. By asking a series of “why” questions, you will find the rationale behind their decisions.

Measure data

Once you’re done tree testing, you’ll want to analyze the results. Make sure to analyze the results, introduce appropriate changes in the content organization, and validate the changes by conducting a series of tree testing.

According to ExperienceUX, there are some measures that you might want to look for in your results:

  • Success: the percentage of users that completed the task vs. failed attempts.
  • Directness: the percentage of users completing the task without hesitation and getting the correct answer the first time.
  • Time: the time it took users to complete a task.

You can also measure the number of attempts to complete a task (known as backtracks). This metric will indicate where items are difficult to find. These results should help you decide whether any problems with your structure relate to the organization of your content or its labeling.

Conclusion

Tree testing is a quick, simple, and inexpensive way to evaluate your content organization. It can help you understand where your users will expect to find content on the site/in the app. It’s impossible to create a perfect structure of content right from the first attempt. Thus, be ready to iterate and validate your design decisions during each design iteration.