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. 2023 Apr 20;10(1):e001478. doi: 10.1136/bmjresp-2022-001478

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© Author(s) (or their employer(s)) 2023. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.

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PRISMA flow diagram.²² BD, bronchodilator; COPD, chronic obstructive pulmonary disease; FEV1, forced expiratory volume in 1 s; FVC, forced vital capacity; GOLD, Global Initiative for Chronic Obstructive Lung Diseases; PRISMA, Preferred Reporting Items for Systematic Reviews and Meta-Analyses.