Multivariate Model of Associations between 6MWT distance and Number of Acute Exacerbations and COPD-Related Hospitalizations Adjusting for FEV1 % Predicted and Prednisone for AE in Previous Year.*

FEV1 denotes forced expiratory volume in 1 second; AE acute exacerbation; ref reference group; and 6MWT denotes 6-minute walk test.*N = 168.§Rate ratios calculated for a MCID of 30 m for 6MWT. The regression coefficients (SE) in natural log risk per 30-m decrease in 6MWT distance predicting AEs and COPD-related hospitalizations are 0.0674 (0.0308) and 0.1624 (0.0502), respectively.