Fig. 1From: Clinical characterization and outcomes of impulse oscillometry-defined bronchodilator response: an ECOPD cohort-based studyStudy flow chart. Abbreviations: ECOPD = Early Chronic Obstructive Pulmonary Disease; IOS, Impulse oscillometry; CT, computed tomography; CPET, cardiopulmonary exercise testing. BD, bronchodilatorBack to article page