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. 2018 Sep 12;13:2859–2868. doi: 10.2147/COPD.S167379

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© 2018 Llanos et al. This work is published and licensed by Dove Medical Press Limited

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Identification of the study population.

Note: ^aParticipants with spirometry-defined COPD were identified using the 2016 GOLD COPD clinical diagnosis standards, requiring participants to have an FEV₁/FVC ratio <0.70 after inhaling a β2-adrenergic bronchodilator medication.

Abbreviations: ACO, asthma–COPD overlap; FEV₁/FVC, forced expiratory volume in 1 second/forced vital capacity; GOLD, Global Initiative for Chronic Obstructive Lung Disease; NHANES, National Health and Nutrition Examination Survey.