Card Sorting
Asking users to group content, which reveals their mental model of a domain rather than your org chart.
Definition
Participants group items into categories that make sense to them. Open sorts let them name the groups; closed sorts use predefined categories to test an existing structure.
Established research. Originates in published research and has been replicated. The effect is real. Its size in your product still needs measuring.
Which variant to run
| Variant | Question it answers |
|---|---|
| Open | How do users naturally group this content, and what do they call the groups? |
| Closed | Does our proposed structure match how users think? |
| Hybrid | Does our structure work, and what is missing from it? |
Running one
- Use 30 to 60 items. Fewer produces thin data; more exhausts participants.
- Label items in the users' words, not internal terminology.
- Fifteen to thirty participants gives reasonably stable clusters for a quantitative analysis.
- Analyse with a similarity matrix or dendrogram rather than by eye.
- Follow up with tree testing, because a sort tells you how people group and a tree test tells you whether they can find things.
In practice
Sorts reveal vocabulary
Information architectureThe names participants give their groups in an open sort are frequently more valuable than the groupings themselves, because they are the labels the navigation should use.
Continue from here
Each link says what the connection is, so you can tell a principle from an alternative from a thing people mix this up with.
Applies when you are designing
Principles behind this
The reasoning this solution is an application of.
- Match Between System and the Real WorldHeuristic
- Mental ModelsMental model
Often used with
These usually appear in the same screen or the same decision.
- Tree TestingResearch method
Sorting proposes a structure, tree testing checks whether people can navigate it.
- Research PlanTemplate
- FigJamTool
- Optimal WorkshopTool
Short definition
The one-paragraph version, for when that is all you need.
- Information ArchitectureTerm
- TaxonomyTerm
Related concept
Connected closely enough to change how you apply this.
- NavigationPattern
- Affinity MappingResearch method
- Information ArchitectureResearch method