Fig. 4

Percent predicted FVC decline 3 years before and 5 years after pirfenidone initiation (pirfenidone-treated population). (a) Slope analysis of the decline in percent predicted FVC in the 3 years before and 5 years after initiation of pirfenidone treatment and (b) Sensitivity analysis of the decline in percent predicted FVC in the population of patients who initiated pirfenidone treatment at or after inclusion in the PROOF registry. FVC forced vital capacity, SE standard error