[R] Discrimination and calibration of Cox model

[David Winsemius]

On Feb 7, 2012, at 11:07 PM, cmh wrote:

> I have been working on fitting Cox model for prediction by using rms  
> package.
> I want to measure model's calibartion and discrimination.  
> Discrimination was
> measured by using validate() in rms, Dxy can be transferred to  
> Harrell's c
> index. But in this way, I cannot get 95%CI of c index. How can I do  
> this in
> R? And by the way, what value should be in c index to present the  
> model's
> well?

Harrell has answered this question several times on this list. It  
shouldn't be that difficult to search them out.
>
> Calibration was using calibrate() in rms, but I cannot get the  
> calibration
> plot which presented the concorance of predicted and observed events  
> in Cox
> model. How can I do this calibration plot of Cox model in R.
>
There _are_ worked examples on the help pages.

>
>
> --


David Winsemius, MD
West Hartford, CT