1.1. Analysis.
Comparison 1 Alpha‐1 antitrypsin versus placebo, Outcome 1 Forced expiratory volume in 1 second (FEV1), change (mL or %).
Comparison 1 Alpha‐1 antitrypsin versus placebo, Outcome 1 Forced expiratory volume in 1 second (FEV1), change (mL or %).