Bioequivalence and Bioavailability Forum • A better place to start.

A better place to start. [Two-Stage / GS Designs]

posted by ElMaestro – Denmark, 2017-11-14 01:04 (1959 d 16:24 ago) – Posting: # 17976
Views: 7,919

Hi d_labes,

❝ But that's not the problem Helmut has described, at least as I understand it. Here we initiate a stage 2 from the perspective of the AUC evaluation where it is not neccessary to initiate one.

Best I can come up with is as follows:
The only thing that determines the need for for stage 2 is the CV.
AUCt is generally having a lower CV than Cmax (for the record, I said 'generally', I did not say 'always'). Often it is about 5-20 percentage points.

So run the sims in the usual fashion, but add 5-20 points on the CV for the power and sample size estimation.

—
Pass or fail!
ElMaestro

Complete thread:

Two PK metrics: Inflation of the Type I Error Helmut 2017-11-12 11:57 [Two-Stage / GS Designs]
- Two PK metrics: Inflation of the Type I Error? d_labes 2017-11-12 17:46
- A place to start ElMaestro 2017-11-12 21:43
  - A place to start? d_labes 2017-11-13 16:02
    - A place to start? Helmut 2017-11-13 16:51
      - Scientific gut feeling d_labes 2017-11-15 10:34
        
        Five minutes gone - power.tsd.2m() arose d_labes 2017-11-15 13:15
    - A better place to start.ElMaestro 2017-11-14 00:04
      - Nope Helmut 2017-11-14 00:21
        
        Nope nobody 2017-11-14 08:11
        I've meditated hard ElMaestro 2017-11-14 12:41