Statistical Analysis
Continuous variables were presented through means, standard deviations,
and medians, whereas categorical variables were presented as
proportions. Parameters with normal distribution were compared by
independent groups (independent samples) t-test whereas for the
parameters without normal distribution Mann Whitney U test was used.
Spearman’s rho correlation analysis was used to analyze the relationship
between two continuous variables that do not distributed normally.
Pearson’s correlation analysis was used in variables that distributed
normally. The χ² test was used for categorical variables and expressed
as observation counts (and percentages). Statistical significance was
accepted when two-sided p value was lower than 0.05. Statistical
analysis was performed using the MedCalc Statistical Software version
12.7.7 (MedCalc Software bvba, Ostend, Belgium; http://www.medcalc.org;
2013).