Proc MI var statement with categorical variables

[VioletaB]

Hello,

I want to use proc mi to impute missing data and i have following question:

In the code below i have in the var statement 2 categorical variables with no missing values and continuous variables that have missing data. 

proc mi data=data1 seed=38467 nimpute=50 out=data_mcmc;

  mcmc impute=monotone chain=multiple;

var treatment gender calcium_v1 calcium_v2 calcium_v3...calcium_v20;

run; 

In this case do i have to include 'by' statement with these 2 categorical variables OR create a dummy variable (0,1) for each category OR no updates are needed in this case? 

[SAS_Rob]

If you are going to use the MCMC statement then you will need to create dummy variables for the categorical variables. 

Unless you have a specific reason for doing so, you could avoid having to impute in two steps by simply using the FCS statement.  This would enable you to use the CLASS statement and avoid having to dummy code.