Data abstraction and analysis
Infants’ characteristics and information were collected from the electronic medical records. Gross findings of the AE tract and associated complications were obtained from the FE reports. Airway malacia was diagnosed when there was greater or equal to 50% reduction in the luminal diameter during spontaneous breathing. Categorical variables are reported as frequency and percentage, while continuous variables are reported with median and interquartile range. All data analyses were performed using Stata 13.1 software.