A one-two punch could still knock us out. Could d
Post# of 148238
The board has talked continuously about the death rate in the "control group," but we should have been more careful to say the "available-for-control population." Consider as follows:
We've discussed population severity comparability, changes in SOC, stress of high load periods and the need to consider the results from the specific hospitals in the trial. I stand by my comment that 28% to 35% (OK, 36%) reflects the sense of this board on that number. Of course, the board could be wrong.
But what if we knew the perfectly-case-comparable death rate at our trial hospitals was at the low end at 28%? Unfortunately, that's not the relevant comparison. We might have also randomly drawn a really healthy 131 patients from the pool of potential controls at those hospitals - there is a 20% chance you would draw 30 or less (23%) deaths. That's the one-two punch we can't handle.
Of course it's equally likely such randomness would work in our favor. I don't think I've been fully recognizing the size of that risk, though. However, it in no way changes prior "significance boundary" calcs, as they refer to observed results.