Statistical analysis
REGRESSION, EVENTS, EVENT
Continuous and discrete variables were summarized at baseline using means (standard deviations) and counts (percentages). Non-normally distributed continuous variables were alternatively summarized using their median and interquartile ranges. The primary efficacy analysis was based on the first occurrence of an event (PU), and we planned an intention-to-treat analysis. We estimated incidence rates (per 1000 person-days of follow-up) and 95% confidence intervals (95% CI) for each study outcome. We conducted a time-to-event analysis to contrast survival and hazard functions between groups. Survival was non-parametrically estimated using the Kaplan–Meier method, and differences between groups were evaluated using the log-rank test. We estimated hazard ratios (HRs) and 95% CI using Cox regression analysis upon testing the proportional-hazard assumption based on Schoenfeld residuals.An interim analysis was planned after reaching the first half of the expected sample size (750 participants) or recorded events (n = 45) by an independent researcher with access to the whole database, including the codes of the study experimental arms