Figure 4

Receiver-operating characteristic (ROC) curves show the diagnostic performance of E-I using dN2 as a functional test of airway obstruction (dN2 cut-off = 2.5% N2/l). The best threshold is reported, alongside the sensitivity and specificity: E-I _MLD = 90.01 (0.79; 0.63) – E-I _-850–1024 = −34.24 (0.65; 0.65) – E-I _-850–910 = −47.23 (0.81; 0.59).