COL1A2 and idiopathic pulmonary fibrosis: Patients with idiopathic UIP (P < 0.01) and idiopathic NSIP (P < 0.05) had a significantly higher expression of type I procollagen in fibroblasts compared with control, while there was no significant difference between CVD-associated UIP and control (1.0 [0–3], 1.0 [0–1.5], 1.0 [0–1.5] and 0.0 [0–1] for idiopathic UIP, CVD-associated UIP, idiopathic NSIP and control, respectively).