Tree testing
Tree testing is a way to evaluate the structure of your website or application, along with card sorting (and is basically a reverse variety of this study) – these two research methods are complementing each other and can provide a better understanding of how the users navigate within your service architecture.
In this kind of study users are asked to complete a specific task and indicate the needed category location in the “tree” – hierarchical category structure of the website or app. Tree testing provides some insights from the customers that can give you a better understanding of the effectiveness of your product’s navigation hierarchy.
Tree testing was pioneered by Donna Spencer in the 2000's and was performed with paper index cards back then. Nowadays, researchers can also use some online digital tools to conduct this kind of study.
You may use tree testing as a follow-up to the card sorting research. It will allow you to evaluate and compare the user-expected website structure and your current product architecture. This approach can be helpful in the advance of designing final page layouts and could let you explore how the menu categories should work.
Process
- First step is to create a study plan and think about all the questions you want to ask your participants. Prepare your website tree structure, get ready with goal-based tasks for users and define the key metrics of your future data analysis. It is also necessary to define the right answer for each task so you can easily calculate the success rate afterwards.
- Find the participants. It is recommended to use at least 50 participants for a tree test.
- Choose the tree testing method: weather it should be run offline or remotely online.
- Launch a pilot run with a small amount of participants. This step is optional but helpful to check if this testing makes any sense for your current situation at all.
- Run your tree test! You may follow-up participants with some survey questions about demographics and the actual product. Keep tree testing sessions from 15 to 20 minutes so it won’t be exhausting and try to ask the users to complete not more than 10 tasks.
- Final step is to analyze the results. Some metrics that are typically included into tree testing data are: success rate, directness, average time and the hierarchy path that was taken by users.
Tree testing is a great opportunity to enhance your product architecture and check if the structure of your product lets the users complete their goals.