Figure 1
From: Epidemiology, genetics, and subtyping of preserved ratio impaired spirometry (PRISm) in COPDGene
Distribution of spirometry in COPDGene. Legend: Forced expiratory volume in the first second (FEV1) is plotted on the x-axis while FEV1/FVC ratio is plotted on the y-axis. Dashed lines represent fixed-threshold criteria used to delineate Preserved Ratio Impaired Spirometry (PRISm) subjects (highlighted in blue-upper left quadrant), control (upper right quadrant), and COPD (lower left quadrant) subjects.