[R] Power calculation

[Padmanabhan, Sudharsha]

HI,

I ran into trouble trying to do a power computation.

In the presence of interaction, I am simulating clinical trials in multiple 
centers.


Suppose I have 3 centers, each with 20 patients, 10 in active drug and 10 in 
placebo and I have efficacy data for the 60 patients, ie, initial and final 
response variable scores for all 60 subjects. How do I compute the power of 
the study? (May be using an f-test?)

Regards

Krishna S P