Categorical variables in Proc PHREG?

cbatzi01 — Fri, 16 Dec 2016 22:38:57 GMT

Hi,

I am using PROC PHREG for time to event analysis. I have a mix of continous and categorical variables to put into the model. Can I put the categorical variables in the class statement of the model, and be OK or do I need to create dummy variables for each of them?

Example:

proc phreg data=Tx1 outest=coxOutput covout plots=survival;
class DIAG_US product2 (ref='HMO') PlanGen (ref='Least Generous') rx_list4 (ref='mono') GDR_CD2 US_Cat(ref='no US') INDYR (ref='2004') ;
model bDMARDtm2*BLGC(0)=
rx_list4
US_Cat
DIAG_US
PlanGen
CIRASScore
OOP
ageonset
QCMI
QCMI6
Product2
INDYR
GDR_CD2
/ties=exact risklimits;
Format DIAG_US Diag_US_txt. product2 product2_txt. Fmastatus2 fmastatus2_txt. GDR_CD3 gdr_cd_txt. plangen plangen_txt. US_Cat US_Cat_txt. rx_list4 rx_List4_txt.;
run;

Thanks!
Chris

Re: Categorical variables in Proc PHREG?

Reeza — Fri, 16 Dec 2016 22:49:12 GMT

Yes, you can use CLASS variables, but you should verify the parameterization method. Typically, PARAM=REF is the one used.

Re: Categorical variables in Proc PHREG?

JacobSimonsen — Tue, 20 Dec 2016 10:19:57 GMT

I agree with Reeza. Most likely, you should use the param=glm option in the class statement.

topic Re: Categorical variables in Proc PHREG? in Statistical Procedures

Categorical variables in Proc PHREG?

Re: Categorical variables in Proc PHREG?

Re: Categorical variables in Proc PHREG?