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. 2022 Mar 5;17:505–515. doi: 10.2147/COPD.S346456

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© 2022 Ding et al.

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Comparison of two lung function test parameters and imaging parameters. (A) Comparison of FEV1/FVC and DL_CO/VC. (B) Comparison of R₅, R₂₀, R₅-R₂₀. (C) Comparison of Fres and Ax. (D) Comparison of X₅. (E) Comparison of LC and EI of whole lungs. (F) Comparison of MED and MLD of whole lungs. Notes: *P < 0.05 compared with NS (no smoking); ^#P < 0.05 compared with FS (quit smoking).

Abbreviation: FEV1/FVC the ratio of forced expiratory volume occupancy in the first second, KCO the ratio of carbon monoxide diffusion to alveolar ventilation, R₅ resistance at 5 Hz, R₂₀ resistance at 20 Hz, R₅-R₂₀ resistance at 5Hz-resistance at 20Hz, X₅ reactance at 5 Hz, Fres resonant frequency, A_X reactance area, EI emphysema index, MED mean emphysema density, MLD mean lung density, LC lung capacity, NS, no significance.