Figure 2

Airflow limitation, emphysema and air-trapping in subgroups defined based on symptoms and physical activity. Based on scores of COPD assessment test (CAT) and Life-Space Assessment (LSA), patients with COPD were classified into 4 groups. There were significant interactions between CAT and LSA on FEV1, In-LAV950%, and Ex-LAV856% (p = 0.04, 0.01 and 0.0001, respectively).