Help using Base SAS procedures

SAS Proc MIANALYZE help needed!

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SAS Proc MIANALYZE help needed!

I have a question on the SAS proc MIANALYZE.

I have a dataset containing missing data, and I used proc MI (MCMC) to generate 5 imputations

Then I ran logistic regression to the imputed dataset (by_imputation), and then ran proc MIANALYZE to combine the results.

One of my variables, Education, was in 3 categories (<high school (ref), high school, >high school). The proc MIANALYZE give me the p-value of each dummy comparing to the ref categories (HS vs <HS; >HS vs <HS). However, I would like to know the overall p-value (Type-3 analysis) of Education itself to the outcome instead of two separate p-values (Education1, Education2).

The Type-3 result normally appears in the un-imputed logistic regression, but I couldn’t find it in the proc MIANALYZE.

How could I obtain an overall p-value for the variable Education in this situation?

I tried treating Education as continuous when I ran logistic and then proc MIANALYZE; however, the result doesn’t seem appropriate. Initially, when Education was treated as categorical, Education1 was significant (HS vs <HS), and the Type 3 (Education overall) in the each imputed logistic was significant (whereas Education2 - >HS vs <HS was not significant). However, when Education was treated as continuous, its p-value became very insignificant, probably due to it’s not an increasing trend (HS – the middle category was causing the significance).

I looked at the SAS proc MIANALYZE manual, and it only showed categorical variables (they call it classification) in 2 categories but not 3. 

Thank you for your help.

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