Figure 5From: Predictors of exacerbation frequency in chronic obstructive pulmonary diseaseSurvival by year in COPD patient group 1, 2A and 2B, experiencing infrequent, mildly frequent and severely frequent exacerbations respectively. Note: Pgroup 1 – group 2 = 0.026, Pgroup 1 – group 2B = 0.009, Pgroup 2 A– group 2B = 0.561.Back to article page