Fig. 3. Subgroup analyses of the risk of “partly controlled asthma” or “uncontrolled asthma” according to baseline asthma duration and baseline air trapping.

The subgroup analyses were evaluated in the per-protocol population to reduce possible statistical biases caused by missing data imputation.

p-MDI, pressurized metered dose inhalers; FP/FOR, fluticasone propionate/formoterol fumarate; DPI, dry powder inhalers; FP/SAL, fluticasone propionate/salmeterol xinafoate; RR, relative risk; CI, confidence interval; RV/TLC, residual volume/total lung capacity.