Fig. 3

Exemplar Item Characteristic Curves (ICC) for items displaying the worst Statistical Misfit. Item characteristic curves for the items displaying the worst statistical misfit. The y-axis represents the scores expected by the Rasch model and the x-axis the depression measurement continuum of the sample. The ICC plots the observed scores in each of the 10 class intervals of depression (the black dots) and the scores expected by the Rasch model at each level of the measurement continuum (the curve). (a) item 49 “I lost weight without trying” of the 51-item bank indicating evident underestimation of depression as observed scores at higher person location logits are located below the expected curve and scores at lower person location logits higher than the expected curve. (b) item 41 “I felt hopeless” of the 28-item bank indicating marginal overestimation of depression as observed scores at higher person location logits are located above the expected curve and observed scores