Fig. 10From: Can roflumilast, a phosphodiesterase-4 inhibitor, improve clinical outcomes in patients with moderate-to-severe chronic obstructive pulmonary disease? A meta-analysisEffect of roflumilast vs. placebo on incidence of COPD exacerbation (patients per total). CI, confidence interval; COPD, chronic obstructive pulmonary disease; M.-H., Mantel-HaenszelBack to article page