Statistical analysis
Continuous data are expressed as mean ± standard deviation or median
(interquartile range). Categorical data are presented as absolute values
and percentages. Tests for significance were conducted using the
unpaired t -test for continuous variables, and the chi-squared
test or Fisher’s exact test for categorical variables. To predict
sufficient ablation lesion formation, receiver-operating characteristic
curves were constructed for different impedance parameter cut-off
values. The area under each curve and 95% confidence interval were
determined using the bootstrap method. Pearson’s correlation coefficient
analysis was performed to assess correlations between continuous
variables. All analyses were performed using SPSS version 22.0 software
(SPSS, Inc., Chicago IL, USA).