Statistical Analysis
cancer, death
CANCER, RELAPSE
Patients who underwent randomization and for whom residual serum samples were available for measurement of p53-Ab levels were included in this analysis. Relapse and death-related outcomes were assessed according to randomization group (ie, whether supplements were taken) as an intention-to-treat analysis. Effects of vitamin D and placebo on the risk of relapse or death were estimated using Nelson-Aalen cumulative hazard curves. A Cox proportional hazards model was used to determine hazard ratios (HRs) and 95% CIs. The p53-immunoreactive subgroup included patients who were p53-Ab (+) in serum and p53-IHC [3+] in cancer cells. To clarify whether vitamin D supplementation affected outcomes in the p53-immunoreactive subgroup but not in the non–p53-immunoreactive subgroup, 