Card sorting - Part 1

David Humphreys and Tania Lang
January 30 2009

This month we include the first article in a three part series on card sorting by David Humphreys and Tania Lang and we share our tip of the month.

Card sorting

Part 1 - An introduction to card sorting

One of the most useful tools in the usability toolbox is card sorting. Anyone with a passing interest in usability has probably heard of it, but they might not really know its true value in the design process.

Card sorting is a great tool in that it gives you an insight into how users group information. Even better, users can also supply terminology that makes sense to them, which can help get you on your way to designing a truly great IA (information architecture).

So what is card sorting?

Card sorting is a user centred design tool that involves users sorting dozens of small cards into logical groups and giving those groups labels that make sense to them. On each card is written the name of a piece of content found on the site. All 50 or so cards together should be a comprehensive representation of the key site content or for the section of the site being redesigned.

The reason card sorting is such a powerful tool is that it is inexpensive and easy to do, but gives great information about the way your users think and how they group information i.e. their "mental model". It can be time consuming but if you prepare well you can start to see results quickly as you become more experienced.

Types of card sorting

  • Open card sorts – The participants are given the cards with no established groupings or categories and are asked to create totally new groups that make sense to them. If you are looking at redeveloping your entire IA then this is the type of card sort you should be looking at doing first.
  • Closed card sorts – The participants are given cards and a set of headings or groupings and are asked to sort the cards into these headings. You might use a closed card sort when you have already established the top level of your IA and want to do some further research on your 2nd level or you have evidence that your top level is working OK (say from usability testing) but users get lost in the lower levels of your IA.

The benefits for the information architect

Why bother with card sorting? Card sorting brings two main benefits:

  • It gives you an understanding of how users group information and what sort of content belongs together and helps you understand your user's "mental model".
  • It gives you suggestions and ideas on the common sorts of terms that they use to describe that information and a starting point for navigation names and link labels.

For example, every intranet we have tested always has a sizeable body of information that covers the interactions the organisations have with their staff. Things like pay, hiring staff, exiting staff, training and development, equity programs, counselling services and investigations are all generally grouped under headings like 'HR' or 'Staff'; never under the name of the HR divisions which usually have names like 'Persons and Organisational Growth'; always important enough to be in a group of their own at 'top level'.

Which is why every intranet IA we've developed thus far has had a 'HR' or 'Staff' label at top level on the recommended site IA. It is important to users and they know what those words mean. Card sorting can tell you this but also provide a powerful tool when the business is trying to meddle in the IA for political reasons or for turf wars.

When should you do card sorting?

Card sorting should be done before any development of the IA happens. You will use the results to help you make decisions about what to group with what and what menu labels are meaningful for users. We usually design the IA after all user research activities are completed so we have an understanding of who the site's users are and what content is important to them. That way we can base the cards on actual user and business requirements and research.

In our next edition of Peak Newsability, we will discuss how to run a card sorting session.

Usability tip

Make sure your website's primary navigation is visually differentiated from any branded headers – otherwise users can struggle to find the nav items

The Gestalt psychology laws of similarity and proximity show that the mind will group together elements that are located spatially near each other, or are of similar colour, size, shape or brightness. So distinguish your primary nav by using contrasting colours or by tweaking the layout so it doesn't completely blend in and disappear.

Categories: Card sorting,Information Architecture