Figure 3.

(A) Annual exacerbation rates in patients with moderate, severe, and very severe COPD receiving B/F or placebo and (B) annual exacerbation rate ratios between B/F and placebo, by disease severity. Vertical lines represent 95% confidence intervals. Moderate COPD was defined as FEV₁ 80%–50% predicted, severe COPD as FEV₁ 50%–30% predicted, and very severe COPD as FEV₁ <30% predicted, according to GOLD 2016 criteria (12-month data set; Calverley et al and Szafranski et al studies only).⁹,¹²

Abbreviations: B/F, budesonide/formoterol; COPD, chronic obstructive pulmonary disease; FEV₁, forced expiratory volume in 1 s.