Fig. 1From: A preference-based item response theory model to measure health: concept and mathematics of the multi-attribute preference response modelSchematic illustration of the Guttman/Rasch data structure. Representation of the raw data (top) and after sorting of the columns (health states) and the rows (patients) in order to arrive at the hierarchical Guttman/Rasch data structure (a check indicates that this health state is preferred over the next health state, a cross indicates a misfit)Back to article page