Statistical Analysis
MONGOL, EVENT
As a feasibility trial, approximately 2000 patients were expected to be enrolled during the study period. For feasible noninferiority purposes, the noninferior margin (Δ) for the primary efficacy end point was set at 1.185 according to a previous publication.Sequential noninferiority analyses were used for the primary end points to explore the feasibility of the coprimary end points and fixed-sequence testing procedure. The end points were analyzed using a fixed-sequence testing procedure in order of (1) safety end point between the rivaroxaban 2.5 mg and enoxaparin groups, (2) safety end point between the rivaroxaban 5 mg and enoxaparin groups, (3) efficacy end point between the rivaroxaban 5 mg and enoxaparin groups, and (4) efficacy end point between the rivaroxaban 2.5 mg and enoxaparin groups. The noninferiority analysis was to be followed by a superiority analysis if noninferiority analysis was concluded.Baseline demographic characteristics, including self-reported race and ethnicity (categorized by Han, Tujia, Miao, and other minority [eg, Hui, Mongol]) were collected prior to randomization. We collected this information to determine whether the racial and ethnic backgrounds of study participants were similar among groups. The baseline characteristics are presented as the mean and SD for continuous variables and frequency and percentage for categorical variables. Survival analyses were based on the time to the first event. The cumulative incidence of the time-to-event end points is expressed as Kaplan-Meier curves over 6 months after randomization. Cox proportional hazard models were used to estimate hazard ratios (HRs) and 2-sided 95% CIs. The The noninferiority analyses for primary end points were sequential, and 1-sided α = .025 was applied for each successive step. For the other analyses, the common 2-sided tests with α = .05 were used. All statistical analyses were conducted using SAS software version 9.4 (SAS Institute). Data were analyzed from November 2021 to November 2022.