Figure 7
From: Exhaled carbon monoxide in asthmatics: a meta-analysis
eCO levels in mild + moderate persistent and severe persistent asthmatics. The WMD of eCO levels between mild + moderate persistent asthmatics and healthy subjects is 0.84 ppm (95%CI: 0.48 to 1.20) using the random effects model. Test for heterogeneity I 2 = 62%. The WMD of eCO levels between severe persistent asthmatics and healthy subjects is 2.20 ppm (95%CI: 0.29 to 4.10) using the random effects model. Test for heterogeneity I 2 = 68%. SD: standard deviation; IV: inverse variance; CI: confidence interval; WMD: weighted mean difference; eCO: exhaled carbon monoxide.