Free association is a technique frequently used for the collection of social representations, notably in the structural approach. Two methods are commonly used for analysing the associations produced. The rank-frequency method, which cross-tabulates the frequency of an item with its appearance ranking; the importance-frequency method (or ranked associations), which replaces the appearance ranking criterion with an importance ranking criterion which consists in ranking a posteriori the elements named. We carried out a comparative analysis of these two methods based on a collection of free association corpora concerning the representations of cancer ( $$N = 55$$ N = 55 ), palliative care ( $$N = 259$$ N = 259 ) and academic success ( $$N = 138$$ N = 138 ). The results indicate that many subjects (82.96 %) make changes to the spontaneously produced representation during the ranking of elements. These modifications directly affect the representational fields and the organisation of the representation. The a posteriori ranking of the representational elements allows the available knowledge on the object of representation to be re-contextualised and the accent to be placed on the functional aspect of the social element which is specific to social representations and not to prototypes.