fig8

Figure 8. Receiver Operating Characteristic (ROC) curves for DS3, GRAF, and Combined (DS3 + GRAF) models predicting fracture risk during enzyme replacement therapy. Panels (A-C) depict ROC curves for each age-at-treatment group: A: < 18 years; B: 18-49 years; and C: ≥ 50 years. Each panel compares the predictive performance of the DS3 score (continuous), GRAF score (ordinal 1-3), and the combined logistic model incorporating both measures. The area under the curve (AUC) is shown for each model. The combined model modestly improved discrimination relative to single predictors, particularly in adults who began therapy before age 50, as indicated by the bootstrap-derived ΔAUC and P-values. Dashed diagonal lines represent the reference line for random classification. GRAF: Gaucher risk assessment for fracture; DS3: disease severity scoring system.