3 Statistical analysis
Continuous variables are expressed as mean ± standard deviation and
compared with the unpaired t-test. Dependent continuous variables were
compared with paired t-test. Categorical variables are expressed as
percentile value and compared with the Chi-square or Fisher’s exact test
as appropriate. Multivariate logistic regression analysis was performed
to adjust the influence of covariates. A general linear model (analysis
of covariance) was applied to evaluate the impact of RFCA on LAA flow
volume while controlling the effect of covariates. Estimated means
calculated by general linear model are presented as mean values with
95% confidence intervals. Results were considered to be significant if
the p-value was <0.05 on a two-tailed test. All statistical
analyses were performed using IBM SPSS Statistics software, Version 24.0
(IBM, Armonk, NY).