Re: How to overlay 2 survival plots with adjustment of confounders

Chung-Li — Thu, 01 Jun 2017 06:39:15 GMT

Sanjay,

Thank you for trying to help!

The SAS I'm using is in version 9.4.

Regarding to the data, it's a traditional survival data which contains

#1 event variable: allcause, 0 as not dead, 1 as dead

#2 follow-up time: followtime

#3 main independent variable: NewSurgeIndex: 1, 2, and 3 represent 3 different groups

#4 other confounders: sex age bmi_1 smoke alcohol ldl_c meansbp nightdaysbpratio

Again, what I'm trying to do is to estimate survival probability for NewSurgeIndex with adjusting for confounders.

Moreover, in order to make these three groups comparable, so I need to draw these three survival curves on the same graph.

Actually, I've came out one way to achieve this:

ODS GRAPHICS ON;
PROC PHREG DATA=one PLOTS(OVERLAY)=SURVIVAL;
		CLASS NewSurgeIndex;
	MODEL followtime*allcause(0)= sex age bmi_1 smoke alcohol ldl_c 
				  meansbp nightdaysbpratio NewSurgeIndex;
	BASELINE COVARIATES=one OUT=Pred1 SURVIVAL=_ALL_/ DIRADJ GROUP=NewSurgeIndex;
ODS GRAPHICS OFF;

However, very welcome if you have any better idea!

Re: How to overlay 2 survival plots with adjustment of confounders

Rick_SAS — Thu, 01 Jun 2017 09:24:59 GMT

Using a categorical variable in the CLASS statement is the usual way to compare groups. As you've seen, this also overlays the various groups on the ODS graphics that the procedure creates.

Re: How to overlay 2 survival plots with adjustment of confounders

Chung-Li — Wed, 07 Jun 2017 02:25:26 GMT

Thank you Rick!
Now I can use it more confidently.

topic Re: How to overlay 2 survival plots with adjustment of confounders in Statistical Procedures

Re: How to overlay 2 survival plots with adjustment of confounders

Re: How to overlay 2 survival plots with adjustment of confounders

Re: How to overlay 2 survival plots with adjustment of confounders