Hi all ,

Background:

I have a dataset with 698 participants. I'm interested in doing multivariate regression analysis.

I have 24 potential covariates (4 of them are continuous, 13 binomial, 7 categorical), 3 dependent variables (continuous: PL, VS, CE) and 1 independent variable (categorical - 6 categories; traj_alcohol). I have missing data on some of my variables (i.e., my potential covariates). I would like to perform multiple imputations and also to conduct univariate analyses with my potential covariates, DV and IV to know which one to include in my final regression model.

My two questions are:

1. Which imputation method to choose? I've tried to use "mvn" but it converted all my categorical variables into continuous ones. Should I impute my variables twice, once for those that are continuous and once for those that are categorical/binomial?

2. Should I impute before or after doing my univariate analyses?

Thank you!