Statistical analysis
REGRESSION, EVENTS
The main analysis at 18 months was identical to that at 3 months. The primary effective variable was the proportion of patients in each group with an mRS score of 0–2 at 18 months. The primary effective analysis involved the difference between the bridging therapy group (control) and the EVT alone group (test). A binomial comparison was used to test the one-sided null hypothesis that the difference in proportions was less than or equal to − 0.10 (H0: PThe treatment effect on dichotomized scores of the modified Rankin scale at 18 months (0 or 1 vs 2 to 6 and 0 to 3 vs 4 to 6) were analyzed with the use of logistic regression, with the odds ratio as the effect variable. An adjusted common odds ratio was applied for a better distribution of outcomes on the modified Rankin scale. All-cause mortality was assessed by means of the Kaplan–Meier method. For the analysis of quality of life, a utility value for each observed EQ-5D-5L health status profile was calculated with the use of an existing algorithm on the basis of valuations elicited by time trade-off techniques applied to the general Chinese population. An unstandardized regression parameter beta was estimated with the use of a multivariable linear regression model and represented the difference between the two treatment groups in the health utility score.As in the original trial, all effect variables were adjusted for potential imbalances between the two groups in the following prognostic variables at baseline: age, baseline NIHSS score, baseline ASPECTS score, onset to randomization time, and occlusion site. To assess the difference between the two treatment groups in the occurrence of long-term major vascular events, a rate ratio was calculated on the basis of person-years at risk. For subjects missing data for long-term major vascular events, analysis was performed with the use of a regression-based multiple imputation.Estimates of treatment effects were presented with 95% confidence intervals, unless specified otherwise. A two-tailed 