Tree Testing VS. Card Sorting

You have most probably already heard about these two techniques. They are the most profound methods when working on improving an Information Architecture of a website. They are both similar and very different, but there is no doubt that tree testing and card sorting complement each other perfectly. Let’s find out what are the main differences between these two methods and how you can benefit from using them in this card sorting vs. tree testing comparison.

We can start with a short description of each technique, in case you need to refresh your memory:

Card sorting is maybe the most known one. In card sorting the tester gets a pack of cards and his/her task is to group them into categories. Card sorting can be performed offline with paper and a pen or online with the help of the online card sorting tool. There are 3 types of card sorting: Open, Closed and Hybrid. Which one to choose depends on the goals of your study and whether you define the names of categories or not. Card-sorting is a good way to design Information Architecture, see what content items go best together, and how users expect them to be sorted and labeled. However, it won’t help you to evaluate the results of an existing IA and tell if your categorization would actually work when it comes to navigating the website.

That is when you’ll need tree-testing (or Treejack) . Tree testing is sometimes called a reverse card sort. Instead of grouping cards into categories, testers get a set of tasks and an existing information architecture. Their goal is to click through the IA labels and try to find the solution to each task.

Card sorting and tree testing can be seen as two different sides of the same coin. That means you will get the best results when you use both at the same time. The ongoing discussion is which one should be first in order to get the best results.

The theory we trust and do follow is the following:

we use card sorting as a first step to get an idea of how people think. With the insights we gathered from a card sort we are able to create our own structure (tree). And as a final step we evaluate the structure with the help of tree testing.

PS: If you’d like to learn more about card sorting, we recommend visiting www.card-sorting.com