Hi everyone,
I want to use MI to analyze an RCT with a primary survival outcome and several multilevel (and survival) secondary outcomes. However, I’m stuck with the question whether I need one or two imputation models because of the specifics of survival / multilevel MI (e.g., considering the multilevel structure which is unnecessary for the survival outcomes). Hu et al. (2016) write a bit about a joint modelling approach when the outcome of the survival analysis really is termination of follow-up, e.g., because of death. However, my outcome is not correlated with the end of follow-up and a clinical parameter (relapse).
Would a joint MI approach, imputing via one model for both survival and multilevel outcomes, be correct or should I favor performing two separate MIs?