Figure 1

Flow chart for selection of study participants. PFT = pulmonary function test; Normal = FEV₁/FVC ≥ 70% and FEV₁ ≥ 80% predicted; Restrictive = FEV₁/FVC ≥ 70% and FEV₁ < 80% predicted; Obstructive = FEV₁/FVC < 70%; Non-user = person who did not use healthcare resources at all with first-listed and secondary diagnosis of COPD; User = person who used any kind of healthcare resource with first-listed and secondary diagnosis of COPD.