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. 2021 Feb 12;16:305–320. doi: 10.2147/COPD.S285338

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© 2021 Leung et al.

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Current vs former smoking as a risk factor for COPD across nine sites. Results are shown for men and women and for the whole cohort. COPD was defined by airflow limitation (FEV1/FVC < LLN); ES (95% CI) is the adjusted odds ratio and 95% confidence interval, aOR (95% CI), adjusted for age, school years, asthma, childhood hospitalization, and dusty job exposure. There is no significant site heterogeneity demonstrated.