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RegisterAUC vs. Cmax [Two-Stage / GS Designs]
Hi Nisha,
The Potvin methods and their derivatives all suffer from one drawback: It is extremely difficult to argue they are usefulk when there is undcertainty about the point estimate. They are almost only useful if the uncertainty is just on the CV.
The reason is that a fixed GMR is used for quantification of the second stage; if you plug in the observed GMR then the methods just outright fail.
Yes, I would write in the protocol that you go by the highest CV or the CV observed for Cmax.
❝ May I ask why it is not so commonly used?
The Potvin methods and their derivatives all suffer from one drawback: It is extremely difficult to argue they are usefulk when there is undcertainty about the point estimate. They are almost only useful if the uncertainty is just on the CV.
The reason is that a fixed GMR is used for quantification of the second stage; if you plug in the observed GMR then the methods just outright fail.
❝ What about a case in which AUC doesn't meet the BE criteria at stage I, but its power is >80% due to the low ISCV, while Cmax power is <80%? Could we still continue to stage II?
Yes, I would write in the protocol that you go by the highest CV or the CV observed for Cmax.
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Pass or fail!
ElMaestro
Pass or fail!
ElMaestro
Complete thread:
- Different power of AUC vs. Cmax at stage I - continuation rules Nisha 2015-09-17 13:28 [Two-Stage / GS Designs]
![[Mix]](https://static.bebac.at/img/mix.png "open in Mix view")
- Different power of AUC vs. Cmax at stage I - continuation rules ElMaestro 2015-09-17 13:56
- Different power of AUC vs. Cmax at stage I - continuation rules Nisha 2015-09-17 20:27
- AUC vs. CmaxElMaestro 2015-09-17 21:53
- Assumption Helmut 2015-09-18 00:15
- Different power of AUC vs. Cmax at stage I - continuation rules Nisha 2015-09-17 20:27
- Different power of AUC vs. Cmax at stage I - continuation rules ElMaestro 2015-09-17 13:56
Ing. Helmut Schütz