When redesigning a website, it can be quite a challenge to figure out how to structure the new site navigation and reorganize content.
But no matter what part of the design process you’re in, card sorting and tree testing research methods can help you define and validate information architecture through feedback from real users. These methods save you a ton of time and development costs by preventing major usability problems that have to be fixed further down the line during your project — or even after the new site launches.
There are 4 major types of card sorting: open, closed, hybrid, and tree testing. All of them can be done the old-fashioned way using actual paper cards or easy-to-create prototypes with real-life users, or they can be conducted online as surveys or with remote users via video calls and screensharing.
“Wherever you are in the design process, card sorting and tree testing can help you define and validate information architecture through feedback from real users.”
Conducting research in-person and online both have their pros and cons, but the important thing is to be sure to involve users whenever you can in your process.
Open card sorting
Open card sorting is a research method to employ early in the process of your redesign. This method helps you take that initial swing at organizing content and figuring out how users would group things on your site. When you haven’t yet spent hours and hours creating your information architecture, open card sorting can get you heading in the right direction.
This method gives you great information on what language users identify with the content and how their brains work. At such a broad level, the data you get is more for your consideration and less directly indicative of what absolutely must be grouped on your new site. This kind of research can help you better understand your users’ perspectives.
How it works:
- Create your “cards” by putting 1 topic or piece of content on each card
- Give the users your stack of cards and ask them to group the cards and make labels for each group
- When you have some results, analyze how users grouped cards and what they named the groups to understand how a user might organize your content. How users sort should influence how content items are grouped in your future site design.
Protip: Try to keep your stack of cards for open sorting under 40 cards. Too many cards means users become frustrated or tired — and they won’t finish your test.
Closed card sorting
Closed card sorting is similar to open card sorting, with the exception that the group names are provided for users to sort into. If you’re far enough into the design process to have some idea of how content should be grouped, this is a great method for validating your ideas. It’s a lot cheaper to do a quick card sort and rearrange your content at this stage than to have to redesign after the site has launched.
Closed card sorting is a good method to use when you already have a hypothesis about how the site navigation model should work. It can be especially helpful to do a quick closed sort after you do an open sort helps you generate the groupings. For the best user experience, test as much as you can.
How it works:
- Create your “cards” by putting one topic or piece of content on each card
- Create your “groups” or category names for users to sort into
- Give users your stack of cards and ask them to sort them into the groups
- Analyze where each card tends to land and how users are sorting content. Is it different from how you sorted the content into those groups?
- Adjust your information architecture design
Protip: For a closed card sort, you can test with up to 50 cards since users don’t also have to create category names.
Hybrid card sorting
Hybrid card sorting, as you might have guessed, is a mixture of open and closed sorting. You provide the user with groups, but the user can edit the group names or create new groups if the ones you provide don’t make sense for them.
Use hybrid card sorting when you have some idea of groups but you’re open to new ideas and new wording. Many participants will stick with what you provided them, but occasionally a few will submit new ideas you might not have thought of that can help you understand their perspective.
How it works: The steps for hybrid card sorting are the same as closed sorting — but users can rename or create new groups for cards.
Protip: If you’ll be conducting an online hybrid card sort, check that your card sort software or website can support this feature. Hybrid card sorting tools are a little more rare than open and closed. At Four Kitchens, we’ve used Concept Codify’s (currently free!) tool for all 3 kinds of card sorting above.
Tree testing bridges the gap between information architecture and usability testing on a prototype or set of wireframes. This type of testing is done on a simplified text-only version of a site’s navigation structure without any navigation aids or visual design.
“Tree testing helps you validate your model before you spend time building a higher fidelity prototype or wireframe.”
Tree testing is best used when you have a site navigation model drafted up already and want to do some very basic task testing before investing any time in visual or interaction design. It can help you validate your model before you spend time building a higher fidelity prototype or wireframe.
How it works:
- Create your site navigation model: outline major categories, subcategories, and pages
- Create tasks for users to complete within your navigation model. These tasks are usually best as “finding” scenarios, testing if a user can find a piece of content within the structure you have designed.
- Input the site navigation model into a system of some sort. It could be a specific testing system like the tree testing product from Optimal Workshop (if you are sending the test out as a survey), or it could be a very basic HTML prototype of your navigation (if you want to conduct the research in-person).
- Give the users the prototype and tasks. Make sure to only give 1 task at a time so the participant isn’t overwhelmed.
- Ask users to tell you when they believe they’re on the right card or page where they’d find the content that the task prompted them to look for
- Analyze the results: where did users think they’d find your content? What paths did they try first? Where did they back up and try a different path? How long did it take them? If you tested in-person, did they express frustration?
Protip: I think this is best done using a digital tool like Treejack from Optimal Workshop, or with a bare bones HTML prototype, because it can be tough to manage this type of testing on paper.
Sort all the things
These 4 information architecture research methods can be used in combination with each other to help guide you through the process of redesigning and restructuring your site content and navigation. Alternatively, each method can be used on its own or in combination with other user research methods like surveys or usability testing to ensure that your site is navigable, usable, and delightful for your end users. Happy redesigning!