Fig. 5

Receiver operating characteristic curve analysis for distinguishing clusters. Receiver operating characteristic (ROC) curve analysis of percentage of predicted forced vital capacity (%FVC), percentage of predicted forced expiratory volume in one second (%FEV1), arterial partial pressure of oxygen (PaOâ‚‚), erythrocyte sedimentation rate (ESR), extent of consolidation in the lower lobes, and Krebs von den Lungen-6 (KL-6) were shown. These ROC curves provided the diagnostic utility of clinical and radiological evaluation in differentiating clusters 1 and 2. ESR, erythrocyte sedimentation rate;Â %FEV1, percentage of predicted forced expiratory volume in one second; %FVC, percentage of predicted forced vital capacity; KL-6, Krebs von den Lungen-6;Â PaOâ‚‚, arterial partial pressure of oxygen.