2.4 Statistical analyses
Statistical analyses were performed with IBM SPSS Statistics 25.0
software (SPSS Inc. Headquarters, Chicago, IL, USA). Deviations from the
Hardy-Weinberg (H-W) equilibrium of the MTHFR C677T/A1298C
genotypes and the associations between categorical variables were tested
using the chi-square test. EFS and OS were analyzed according to the
Kaplan-Meier (K-M) method using the patient follow-up; differences were
compared using the log-rank (Mantel Cox) test. The K-M survival curves
were plotted using GraphPad Prism 8.0 (GraphPad Software, San Diego, CA,
USA). P -values < 0.05 were considered significant. All
data in our study have been recorded at SYSUCC for future reference
(RDDA2020001559, https://www.researchdata.org.cn).