Statistical analysis
VTE
REGRESSION
All statistical analyses will be governed by a comprehensive statistical analysis plan, authored by the study statisticians and agreed by the independent Trial Steering Committee (TSC).The main analysis will be according to the intention-to-treat principle and will compare the rates of VTE at 90 days, measured at an individual level, using hierarchical (multilevel) logistic regression, adjusting for any other prespecified strongly prognostic individual baseline covariates and site-level baseline covariates, with site itself as a random effect. This will be performed independently by the Edinburgh Clinical Trials Unit who will have sole access to the final REDCap dataset. The findings will be assessed for robustness against any missing data, first using multiple imputation assuming this data are missing at random and, if appropriate and the data permit, further sensitivity analyses will be attempted under any plausible missing data mechanisms not missing at random. Secondary outcomes will be analysed in a similar fashion with generalised linear models appropriate to the distribution of the outcome. Safety data will be summarised descriptively.