Statistical Analysis
The primary endpoint was comparison of tissue outcomes between baseline and 24 weeks (six months) of treatment with mepolizumab. Statistical analyses were performed using SPSS version 26 (SPSS Inc., United States),24 and graphs were presented using GraphPad Prism 8 version 8.2.1 (GraphPad Software, United States).25 Descriptive statistics were given for demographics, baseline characteristics, and outcome measures. Mean and standard deviation (SD) were summarised for normally distributed continuous variables. Median and interquartile range (IQR) were summarised for continuous variables that were not normally distributed and for ordinal variables. Frequencies were summarised for nominal variables. Parametric results were expressed as mean±1 SD. Non-parametric results were expressed as median [IQR]. Paired samples t-test was utilised for continuous data. For ordinal data with less than four levels, data was transformed into binary nominal variables. Pairwise analysis for baseline versus Week 24 was performed using McNemar’s test for proportions. For variables scored by more than one reviewer, the average measures Intraclass Correlation Coefficient was calculated. All p -values were 2-tailed and a value of <0.05 was considered statistically significant.