Statistical analysis
Statistical analyses were performed using commercially available
computer software (SPSS v 21.0, Chicago, IL, USA). Descriptive
statistical analyses were undertaken on patient characteristics and the
results of IEE. Nonparametric qualitative and quantitative comparisons
were performed using Pearson chi-square or Fisher’s exact test. For all
analysis, a two-sided P‐value of 0.05 or less was considered
statistically significant.