Aaaaargh. My half yearly scream of just *please* show me (grant reviewer) you (applicant) have done a power analysis. I honestly don't want much - just something to show you have thought through whether your data gathering + analysis experiment has some hope in working.
It's just not good enough to either (a) not talk about it at all (they will send it to reviewers like me) or (b) imply that you get a pass because you will be doing nearly all the cases in country / hospital / region or the maximum mice you can fund.
For (b) I firstly don't buy you will be able to do all (no one ever is) and secondly the point of a power calculation is whether you have some hope of making an inference. If you can't get enough samples to have that hope then ... its a pretty pointless study.
As I've often said, this is about showing that you (the applicant) aren't fooling *yourself* about what is inferable or not. You can always 'fudge' a power calculation (via setting an effect size) it's just the honesty about the effect size with yourself I want to see
I would literally give more marks for power calculations done on the back of the envelope and using your mobile phone to take a picture of the envelope. It's not that hard to do a power calculation. it is a sentence.
"Assuming the effect size of the treatment is similar to Wibble's study of Wobble (ref), we calculate that there is a 80% chance of us observing an effect with this sample size". Not "we will do 50 patient samples which is the maximum yearly number in our hospital".
