Fig. 3

ROC Curves for Patients with Severe Disease. A ROC curve was generated for all 12 variables (i.e., 10 self-assessment variables and 2 blood test parameters) that showed strong correlation with disease severity (blue line, AUC = 0·72, p < 0·0001). Then, separate ROC curves were generated for the 10 variables in the final self-assessment scale (green line, AUC = 0·71, p < 0·0001) and for the same 10 variables, in the older-aged (not less than 65 years old) patients (red line, AUC = 0·75, p < 0·0001). ROC, receiver operating characteristic; AUC, area under the (ROC) curve