Dear Michael,
Thank you very much for a such quick reply! Would you mind if I ask you some
more details.
Because my database is multi-record one (datas are annualy recorded for each
ID), I want to distinguish covariate between baseline and endpoint.
How can I restrict the subjects to "smokers at baseline", and to "smoker at
endpoint"?
e.g. make analysis only among subjects who are smokers (smoke==1) at the
time of the baseline(_t0==0).
* stcox Exposure Covariate1 Covariate2 if smoke==1 ??
e.g. make analysis only among subjects who are smokers at the time of the
endpoint.
* stcox Exposure Covariate1 Covariate2 if smoke==1 ??
I am using "stcox" and "sts graph(Kaplan-Meier)" commands.
Thank you in advance.
Tastauhiko KUBO
----- Original Message -----
From: "Michael McCulloch" <[email protected]>
To: <[email protected]>
Sent: Tuesday, October 07, 2008 10:36 AM
Subject: Re: st: restrict subjects for analysis from multi-record data
Hello Tatasuhiko,
If you are using the command -stcox-, then you restrict using the
-if- command, for example:
stcox MainExposure Covariate1 Covariate2 if smoke==1
Distinguishing between baseline and endpoint would need other
variables, which can also be used after -if-.
Michael
>Dear colleges,
>
>I am now making a survival analysis using the multi-record data.
>
>Now, I want to restrict the subjects for analysis regarding their life
>styles.
> >> e.g. make analysis only among subjects who are smokers (smoke==1) at
>the time of the baseline(_t0==0).
> >> e.g. make analysis only among subjects who are smokers at the time
> of
>the endpoint.
>
>In this case what command should be used to restrict the subjects?
>
>
>Thank you.
>
>
>From Tatasuhiko KUBO
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