KOCOSS cohort data
airflow obstruction, COPD
COPD
We used data from the KOCOSS cohort (registered on ClinicalTrials.gov with identifier CT02800499), an ongoing, prospective observational cohort of COPD, which has been recruiting patients from 48 referral hospitals in Korea since 2012.Patients with COPD in the KOCOSS cohort were eligible if they were aged ≥ 40 years and exhibited a fixed airflow obstruction, as defined by a post-bronchodilator forced expiratory volume in 1 s (FEV