Fig. 3From: Psychometric properties of the patient-reported outcomes measurement information system scale v1.2: global health (PROMIS-GH) in a Dutch general populationThe overall impact of Differential Item Functioning of Global08 (fatigue) for age on the Test Characteristic Curve (TCC). The TCC shows the relation between the total item scores (y-axis) and theta (x-axis) (N = 4370)Back to article page