Fig. 2
From: Validation of a method to assess emphysema severity by spirometry in the COPDGene study
Distribution of ESI values across the different emphysema subgroups as assessed by CT. White bars represent the percentages for NE (no emphysema, %LAA-950insp < 6), light gray bars for ME (moderate emphysema, 6 ≤ %LAA-950insp < 14), and dark gray bars for SE (severe emphysema, %LAA-950insp ≥ 14). Data in the table represent absolute numbers (percentages). The Goodman and Kruskal’s Gamma for the corresponding contingency table is G = 0.82, p < 0.001