Interstitial lung disease with progressive fibrotic phenotype in diseases classified elsewhere

**Inclusion terms:** - Progressive fibrotic interstitial lung disease

**Code first:** - underlying disease, such as: - lung diseases due to external agents (J60-J70) - rheumatoid arthritis (M05.00-M06.9) - sarcoidosis (D86.-) - systemic connective tissue disorders (M30-M36)