cox model

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cox model

Medic
I need a R-code for a situation that is well described in the sas help. I
would be very grateful for the help!
"Time-dependent variables can be used to model the effects of subjects
transferring from one treatment group to another. One example of the need
for such strategies is the Stanford heart transplant program. Patients are
accepted if physicians judge them suitable for heart transplant. Then, when
a donor becomes available, physicians choose transplant recipients
according to various medical criteria. A patient’s status can be changed
during the study from waiting for a transplant to being a transplant
recipient. Transplant status can be defined by the time-dependent covariate
function z=z(t) as:
z(t)= 0 (if the patient has not received the transplant at time t)
and 1 (if has received)

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PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.
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Re: cox model

David Winsemius
It's also "well described" in the help materials for the obvious
recommended package that ships with every copy of R. My copy sits at
http://127.0.0.1:29434/library/survival/doc/timedep.pdf. Therneau's S
package was first ported to R by Thomas Lumley and later Therneau took
over maintenance.

--

David.

On 11/3/18 12:51 PM, Medic wrote:

> I need a R-code for a situation that is well described in the sas help. I
> would be very grateful for the help!
> "Time-dependent variables can be used to model the effects of subjects
> transferring from one treatment group to another. One example of the need
> for such strategies is the Stanford heart transplant program. Patients are
> accepted if physicians judge them suitable for heart transplant. Then, when
> a donor becomes available, physicians choose transplant recipients
> according to various medical criteria. A patient’s status can be changed
> during the study from waiting for a transplant to being a transplant
> recipient. Transplant status can be defined by the time-dependent covariate
> function z=z(t) as:
> z(t)= 0 (if the patient has not received the transplant at time t)
> and 1 (if has received)
>
> ______________________________________________
> [hidden email] mailing list -- To UNSUBSCRIBE and more, see
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.

______________________________________________
[hidden email] mailing list -- To UNSUBSCRIBE and more, see
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.
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Re: cox model

Jeff Newmiller
In reply to this post by Medic
Stop re-posting this question.  It only irritates people... it does not improve your chances of getting help.

What does improve your chances is reading the Posting Guide and following the advice given there. Your question amounts to asking someone to figure out what theory you should apply to a problem domain... which is not really on topic here, though someone might recommend something to you anyway.

The better strategy would be to seek out (elsewhere) what textbook/papers you want to apply (SAS should suggest references if they claim to implement solutions) and then use Google or rseek.org to find contributed packages that implement some or all of the steps in that approach. You can also peruse the Task Views on CRAN. When you get error messages trying to apply those tools in R, ask here how to resolve those problems, since this list is about the language not your problem domain.

On November 3, 2018 12:51:23 PM PDT, Medic <[hidden email]> wrote:

>I need a R-code for a situation that is well described in the sas help.
>I
>would be very grateful for the help!
>"Time-dependent variables can be used to model the effects of subjects
>transferring from one treatment group to another. One example of the
>need
>for such strategies is the Stanford heart transplant program. Patients
>are
>accepted if physicians judge them suitable for heart transplant. Then,
>when
>a donor becomes available, physicians choose transplant recipients
>according to various medical criteria. A patient’s status can be
>changed
>during the study from waiting for a transplant to being a transplant
>recipient. Transplant status can be defined by the time-dependent
>covariate
>function z=z(t) as:
>z(t)= 0 (if the patient has not received the transplant at time t)
>and 1 (if has received)
>
>______________________________________________
>[hidden email] mailing list -- To UNSUBSCRIBE and more, see
>https://stat.ethz.ch/mailman/listinfo/r-help
>PLEASE do read the posting guide
>http://www.R-project.org/posting-guide.html
>and provide commented, minimal, self-contained, reproducible code.

--
Sent from my phone. Please excuse my brevity.

______________________________________________
[hidden email] mailing list -- To UNSUBSCRIBE and more, see
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.
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Re: cox model

David Winsemius
In reply to this post by Medic
It's also "well described" in the help materials for the obvious
recommended package that ships with every copy of R. My copy sits at
http://127.0.0.1:29434/library/survival/doc/timedep.pdf. Therneau's S
package was first ported to R by Thomas Lumley and later Therneau took
over maintenance.

--

David.

On 11/3/18 12:51 PM, Medic wrote:

> I need a R-code for a situation that is well described in the sas help. I
> would be very grateful for the help!
> "Time-dependent variables can be used to model the effects of subjects
> transferring from one treatment group to another. One example of the need
> for such strategies is the Stanford heart transplant program. Patients are
> accepted if physicians judge them suitable for heart transplant. Then, when
> a donor becomes available, physicians choose transplant recipients
> according to various medical criteria. A patient’s status can be changed
> during the study from waiting for a transplant to being a transplant
> recipient. Transplant status can be defined by the time-dependent covariate
> function z=z(t) as:
> z(t)= 0 (if the patient has not received the transplant at time t)
> and 1 (if has received)
>
> ______________________________________________
> [hidden email] mailing list -- To UNSUBSCRIBE and more, see
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.

______________________________________________
[hidden email] mailing list -- To UNSUBSCRIBE and more, see
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.