Table S2. The diagnostic methods distribution of ILD patients.
| Subtype of ILD | Surgical lung biopsy (n=24, 28.2%) | Bronchoscopy (n=24, 28.2%) | HRCT (n=9, 10.6%) | Serum autoantibody test + muscle/labial gland biopsy (n=28, 32.9%) |
|---|---|---|---|---|
| IIP | 22 | 28 | 9 | 0 |
| IPF | 11 | 0 | 9 | 0 |
| Possible IPF | 0 | 7 | 0 | 0 |
| Non-IPF | 11 | 21 | 0 | 0 |
| NSIP | 11 | 7 | 0 | 0 |
| Cellular NSIP | 6 | 4 | 0 | 0 |
| Fibrotic NSIP | 5 | 3 | 0 | 0 |
| Others IIP | 0 | 7 | 0 | 0 |
| CTD-ILD | 2 | 3 | 0 | 28 |
| PM/DM-ILD | 0 | 0 | 0 | 19 |
| RA-ILD | 1 | 1 | 0 | 1 |
| Sjogren’s syndrome-ILD | 0 | 0 | 0 | 1 |
| SLE-ILD | 0 | 1 | 0 | 1 |
| SSc-ILD | 0 | 1 | 0 | 1 |
| Mixed CTD-ILD | 0 | 0 | 0 | 5 |
| Undifferentiated | 1 | 0 | 0 | 0 |
28.2% of patients were separately diagnosed based on the surgical lung biopsies or bronchoscopy, 32.9% of patients were diagnosed based on immunological markers and muscle/labial gland biopsy, and 10.6% patients were diagnosed by HRCT. ILD, interstitial lung disease; IIP, idiopathic interstitial pneumonia; IPF, idiopathic pulmonary fibrosis; NSIP, non-specific interstitial pneumonia; CTD, connecting tissue diseases; PM/DM, polymyositis/dermatomyositis; RA, rheumatoid arthritis; SLE, systemic lupus erythematosus; SSc, systemic scleroderma; HRCT, high-resolution computed tomography.