Suppose I have a dataset, and I want to use it to analyse the association between BMI and stroke. The dataset has some missingness for BMI(independent variable) and some missingness for covariates such as blood pressure. There are many complete covariates and suppose the dataset could be imputed.
My question is whether I could impute the BMI (independent variable) and missed covariates using other complete covariates? A coauthor said that what I could impute is only covariates, not independent variable. Is it right?
If the outcome (dependent variable) is also missed, could I impute that? (impute independent and dependent variables and covariates using other complete variables?)