Additional file 1 of Small airway dysfunction in Chinese patients with idiopathic pulmonary fibrosis

Additional file 1: Table S1. Clinical characteristic differences between patients with SAD and without SAD. Table S2. Univariate logistic regression analysis of the risk factors as categorical variables for SAD. Figure S1. Forest plot of univariate analysis of the risk factor as continuous variables for SAD. Figure S2. ROC curves of spirometry parameters in predicting SAD. A, FEV1; B, FVC; C, FEV1/FVC; D, FEV3/FVC; E, PEF.