Statistical analysis
Statistical analysis was performed using the NCSS (Number Cruncher
Statistical System) 2007 (Kaysville, Utah, USA). Continuous variables
were presented as mean ± standard deviation and median with
interquartile ranges as appropriate and categorical variables as
frequency and percentage. To test the normality of distribution, the
Kolmogorov Smirnov test was used. Differences between the two groups
were evaluated using Student’s t-test for normally distributed variables
and Mann-Whitney U test for variables without normal distribution. The
Chi-square or Fisher’s exact test was used to compare categorical
variables as appropriate. The Wilcoxon Signed Ranks Test was used in the
evaluation of hemoglobin measurements before and after the procedure.
Survival analysis with a log-rank test was conducted for the combined
end-point of death between the two groups, and Kaplan-Meier curves were
created. Logistic regression analysis was used to evaluate the
independent effects of the baseline variables on procedure failure and
mortality. The odds ratios (OR) and 95% confidence intervals (CI) were
calculated. A p-value <0.05 was considered significant.