Statistical Analysis
Patient demographic and baseline clinical data were summarized with
standard descriptive statistics. All continuous study outcome data were
summarized using means (±SD). Post- vs pre-treatment measurements for
each drug therapy were compared using paired t-tests. Linear mixed
effects models were then used to compare outcome data between the
albuterol dose levels and saline placebo. Each model included fixed
effects indicator variables for the treatment period (1-3) and within
period treatment dose (1-6) to account for any potential temporal
effects on the outcome measurements. A random effect (random intercept)
for the study participant, robust standard errors, and an unstructured
covariance matrix were used in all models. Rates of occurrence for
categorical tolerability outcomes were calculated. All statistical
analyses were performed using STATA/SE 15.1 (StataCorp, College Station,
TX).