power analysis for prop trend test

Breslow & Day has a nice three page discussion in volume 2 of their  
"Statistical Methods in Cancer Research". See pages 285-7. Most of the  
gain in power comes from the decrease in degrees of freedom and only  
if the trend is approximately linear. Alternatives that are quadratic  
are not well detected.

Failing that,  the usual answer is simulate it.

David Winsemius
On Mar 2, 2009, at 6:12 PM, Bill Hyman wrote:

>
> Hi all,
>
> Is there any way we can to power analysis for prop trend test? Many  
> thanks!
>
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