Re: st: RE: Power calculation for competing risks regression

[Richard Goldstein <richgold@ix.netcom.com>]

I disagree that a post-hoc power analysis is ever a good idea (see
http://www.stat.uiowa.edu/~rlenth/Power/ for more on this)

instead I recommend looking at the CI's and seeing whether anything of
substantive interest is included in the CI; if yes, you have
insufficient power; if no, I see no problem

Rich

On 8/22/11 11:29 AM, Hackney, David wrote:
> Hello all,
> 
> Does anyone have advice on power (or sample size) calculations for competing risks (stcrreg) in Stata? We did a competing risks regression and found that the HR for the variable of interest was non-significant and the reviewers (reasonably) asked for a post-hoc power analysis to provide support for our conclusion. There is no competing risk model specific power calculation which appears to be available, though I didn't know if one of the other power commands could be modified to accommodate competing events, or if a user-written program existed (I couldn't find one with the search function). Thanks.
> 
> David Hackney
> 
>  
> 
> PS.  My apologies if I have sent this multiple times, I'm just not sure if I have done it correctly.  Thanks.
> 
>  
> David N Hackney MD, MS
> Assistant Professor
> Division of Maternal-Fetal Medicine
> Department of Obstetrics and Gynecology
> University of Rochester Medical Center
> Phone (admin assistant): 585-275-7480 
> Fax: 585-256-1416
> david_hackney@URMC.rochester.edu
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