Statistics analysis
hemorrhagic transformation, hemorrhagic
REGRESSION, SECONDARY
We first compared the differences in late lesion, non-hemorrhagic and hemorrhagic growth between the patients that were randomized to receive IVT with EVT or direct EVT using Mann-Whitney U test. Next, we determined the association between (intention to) administering IVT and lesion, non-hemorrhagic or hemorrhagic evolution using univariable linear regression. We investigated the influence of successful treatment (eTICI: 2 b-3) on the lesion, non-hemorrhagic and hemorrhagic volumes on the complete study population and within each of the treatment arms.Primary outcome was the 90-day modified Rankin Scale (mRS) and the secondary outcome was defined as favorable functional outcome (mRS ≤ 2). We assessed the influence of late lesion, non-hemorrhagic, and hemorrhagic growth on functional outcome using univariable and multivariable ordinal logistic regression after adjusting for confounders (baseline, clinical and imaging characteristics that were associated with functional outcome at the significance level of p < 0.1). To assess the influence of IVT on these associations, we performed unadjusted interaction analysis by introducing a multiplicative term of IVT with the parameter under consideration. We also repeated these analyses with favorable functional outcome as the outcome variable. Lastly, to remove the confounding effect of hemorrhagic transformation on the association between late lesion growth and outcome, we performed univariable and multivariable ordinal regression in the sub-group of patients that did not suffer from a hemorrhagic transformation.Statistical analyses were performed using SPSS (IBM SPSS Statistics, version 26, 2019) and R (Version 4.0.2 [2020-06-22]) using RStudio (Version 1.2.5033 2009–2019 RStudio, Inc.) packages: MASS, dplyr, reshape, ggeffects, foreign, ggplot2, DescTools, ggpubr. A P ≤ 0.05 was considered statistically significant.