Sample size and statistical analysis
CRBD
GASTROINTESTINAL CANCER
Sample size calculation was performed using the PASS 15.0 (NCSS LLC., Kaysville, U.T., USA). The current results showed that CRBD occurred in 70% of male patients undergoing laparoscopic radical resection of gastrointestinal cancer (based on our unpublished pilot data). Assuming a rounded 40% rate of CRBD in the magnesium group, we calculated a total sample size of 104 male patients (52 in each group) with a two-sided alpha level of 0.05, a power of 0.8, and a 20% dropout.The data are expressed as mean ± standard deviation, median (interquartile range, IQR), number (proportion), relative risk (RR), and 95% confidence interval (95% CI). Continuous data were checked for normality using the Shapiro–Wilk test. The continuous normally distributed variables were compared using Student’s t-test; whereas the Mann–Whitney and Wilcoxon tests were used for non-normally distributed variables. Two or more proportions were compared using the chi-square test or Fisher’s exact test as appropriate. Repeated measures ANOVA was used for analyzing the differences between variables over a period. Statistical analysis was carried out using SPSS v26.0 (IBM Corp., Armonk, N.Y., USA).