2.4. Statistical Analysis:
The data were compiled and summarized in a Microsoft Excel (2019)
spreadsheet, and subsequent statistical analysis was conducted using
SPSS software version 22. Quantitative variables were summarized by mean
and standard deviation, while categorical variables were represented
through frequency and percentage. The normality of numerical data
distribution was assessed through the Kolmogorov–Smirnov test, and
variance homogeneity was evaluated using the Levene test. We employed
Kaplan–Meier survival curves to determine overall survival rates, and
differences between survival curves were compared via the log-rank test.
Additionally, we utilized a Cox regression analysis to investigate the
impact of independent variables on overall survival. Statistical
significance was established at a threshold of 0.05, with results
considered significant if the p-value was less than 0.05. All reported
findings include a 95% confidence interval to ensure accuracy and
reliability.