Rashmi Sinha describes free-listing as a method for discovering how participants naturally understand a domain, its scope, its boundaries, and the vocabulary they use for it. In a free-listing session, you simply ask participants to list everything that belongs to a category, "name all the types of products you can think of", and prompt them to keep going if they stop early. There's no sorting or grouping involved, just an open-ended list.
Two things make the resulting data useful. Average rank distance tells you how central or related items are to each other, based on how early participants list them and how close together they mention related items. Co-occurrence tells you how frequently different participants independently mention the same items, which reveals what's genuinely salient to the domain versus idiosyncratic to one person. Free-listing typically happens early, before or in place of card sorting, and can directly inform the terminology you use when preparing category cards for a later closed card sort.
Card sorting assumes you already have the right cards. Free-listing is how you find out whether the cards you were about to create even match how people think about the domain in the first place.
Correct: whether the team's assumed vocabulary and category boundaries actually match how specialist nurses think about the domain. Free-listing exists precisely to surface a domain's actual scope and vocabulary from the people who live inside it, rather than relying on outsiders' assumptions about what belongs and what it should be called.
In this specific situation, skipping free-listing carries real risk. If the IA team creates card-sorting cards based on their own guesses at clinical terminology, they could easily produce cards that use the wrong terms entirely, or that carve up the domain along boundaries that don't match how nurses actually think about it. The nurses in the card sort would then be reacting to a flawed starting point rather than revealing their genuine mental model, the card sort's results would be shaped as much by the team's mistaken assumptions as by the nurses' actual thinking.Given the specialized, unfamiliar vocabulary described here, running free-listing first is the stronger choice despite the limited budget. It's a relatively quick, low-cost method, the source material notes it can be conducted efficiently even verbally, and its output directly improves the quality of the cards used in the card sort that follows, which protects the value of that larger research investment rather than undermining it.