4 options for running a card sort

3 min read Andrew Mayfield

This morning I eavesdropped a conversation between Amy Worley (@worleygirl) and The SemanticWill™ (@semanticwill) on “the twitters“.

Aside from recommending two books by Donna Spencer (@maadonna), I asked Nicole Kaufmann, one of the friendly consultants at Optimal Usability, if she had any advice for Amy about reorganising 404 books into categories that make more sense.

I don’t know Amy’s email address and this is much too long for a tweet. In any case I thought it might be helpful for someone else too so here’s what Nicole had to say:

In general I would recommend having at least three sources of information (e.g. 1x analytics + 1 open card sort + 1 tree test, or 2 card sorts + 1 tree test) in order to come up with a useful and reliable categorisation structure.

Here are four options for how you could consider approaching it (starting with my most preferred to least preferred):

Option A

  • Pick the 20-25 cards you think will be the most difficult and 20-25 cards that you think will be the easiest to sort and test those in one open card sort.
  • Based on the results create one or two sets of categories structures which you can test in a one or two closed card sorts. Consider replacing about half of the tested cards with new ones.
  • Based on the results of those two rounds of card sorting, create a categorisation structure and pick a set of difficult cards which you can turn into tasks which you can test in a tree test.
  • Plus: Categorisation is revised between studies. Relative easy analysis.
  • Minus: Not all cards have been tested. Depending on the number of studies needs about 80-110 participants. Time intensive.

Option B

  • Pick the 20-25 cards you think will be the most difficult and 20-25 cards that you think will be the easiest to sort and test those in one open card sort.
  • Based on the results do a closed card sort(s) excluding the easiest cards and adding some new cards which haven’t been tested before.
  • Plus: Card sort with reasonable number of cards, only 40-60 participants needed, quick to analyse.
  • Minus: Potential bias and misleading results if the wrong cards are picked.

Option C

  • Create your own top level categories (5-8) (could be based on a card sort) and assign cards to these categories, then pick random cards within those categories and set up a card sort for each (5-8).
  • Based on the results create a categorisation structure and a set of task which will be tested in a tree test.
  • Plus: Limited set of card sorts with reasonable number of cards, quick to analyse. Several sorts for comparison.
  • Minus: Potential bias and misleading results if the wrong top categories are picked. Potentially different categorisation schemes/approaches for each card sort, making them hard to combine into one solid categorisation structure.

Option D

  • Approach: Put all 404 cards into 1 open card sort, showing each participant only 40-50 cards.
  • Plus: All cards will have been tested
  • Do a follow up card sort with the most difficult and easiest cards (similar to option B).
  • Minus: You need at least 200-300 completed responses to get reasonable results. Depending on your participant sources it may take ages to get that many participants.

Published on August 1, 2012

Andrew Mayfield