Statistical analysis
Continuous variables are expressed as mean +/- SD, or median and
interquartile range (IQR). Two-sided unpaired Student t -test was
used to compare continuous variables that satisfied the normality
assumption. Non-parametric Wilcoxon test was used for data that deviated
from normality. Categorical and binary variables are presented as
frequencies (percentages). Chi-square and Fisher exact test were used to
compare the frequency distribution of categorical variables. Analysis of
variance (ANOVA) was used to analyse the differences among group means.
Two-tailed values of P < 0.05 were considered statistically
significant. The IBM SPSS Statistic version 25 software was used for the
statistical analysis (SPSS, Chicago, Illinois).