Figure 1. Cohort Development and Participant Classification in the CAPTURE Trial.

The number of patients approached for enrollment was not available because these data were not collected at all study sites. Not all patients approached were eligible because screening included queries related to self-reported prior chronic obstructive pulmonary disease (COPD) diagnosis, recent myocardial infarction, recent respiratory infection treated with antibiotics, and cataract surgery. CAPTURE indicates COPD Assessment in Primary Care To Identify Undiagnosed Respiratory Disease and Exacerbation Risk; FEV₁, forced expiratory volume in the first second of expiration; FVC, forced vital capacity.

^aAt analysis time, it was found that FEV₁ prediction inputs (sex, race, age, and height) recorded during spirometry sometimes disagreed with the values recorded separately in the study forms, and the correct values could not be verified. Patients with a resulting discrepancy of greater than 5% in the FEV₁ predicted value were excluded from the analysis.