The results showed that observed changes in decorin concentrations allowed for accurate differentiation between children with JIA and healthy children (AUC = 0.813, p = 0.026), as presented in Figure 6a, and moderate differentiation between patients before and after treatment (AUC = 0.743, p < 0.0001), as shown in Figure 6b. Here, DCN is linked to juvenile idiopathic arthritis.