Statistical Analysis
Tumor
REGRESSION, DISEASE, ADVERSE EVENTS, TUMOR
We hypothesized that median intracranial PFS be prolonged from 8 months in the gefitinib-alone group to 12 months in the gefitinib plus chemotherapy group. Assuming a hazard ratio (HR) of 0.67 for gefitinib plus chemotherapy vs gefitinib alone, with 80% power and 1-sided α value of 10%, our estimated sample size was 160 patients.Intention-to-treat analysis was performed. Intracranial PFS, PFS, and OS were estimated using Kaplan-Meier curves, and differences between groups were compared with a stratified log-rank test. Hazard ratios and 95% CIs were evaluated with Cox proportional hazards regression models. Tumor overall objective response rate, disease control rate, and incidence of adverse events were compared with the Fisher exact test between the 2 treatment groups. All end points are reported as 2-sided 