SABA are used for quick relief of asthma symptoms. To measure SABA use, at each clinical visit patients were asked to recall their usage of SABA therapy within the last 3 days of the scheduled visit. If usage was confirmed, the number of puffs used was recorded. For the purpose of summaries, an average daily usage was evaluated by dividing the total number of puffs recorded over 3 days by 3.
The during treatment (Weeks 4, 8, 12 and 16) average SABA use was estimated using a mixed-effect model for repeated measures (MMRM) with fixed effects (treatment, stratification factors, sex, visit, interaction of treatment and visit), covariates (height, baseline value), and patient as the random effect for the repeated measurements.
Negative change from baseline scores indicate improvement in asthma control.