Bioequivalence and Bioavailability Forum • two-stage design power 90% second stage

two-stage design power 90% second stage [Two-Stage / GS Designs]

posted by ElMaestro – Denmark, 2012-08-02 12:17 (5077 d 23:48 ago) – Posting: # 9019
Views: 18,114

Hello Yvonne,

❝ My question is, if we go into the second stage and we have to do a sample size calculation, can we use a power of 90% (instead of 80%)? And of course more importantly :-D , would a sample size calculation based on 90% power be accepted by the authorities?

Yes, this will be acceptable to many authorities.

❝ In theory the power is the companies risk and not the consumers risk and thus no extra inflation of alpha would occur in a two stage design (because of a different use of power) or am I wrong here :confused: .

You probably need to prove that the overall alpha is preserved under or at 0.05. A simulation study is recommended for this purpose.

—
Pass or fail!
ElMaestro

Complete thread:

two-stage design power 90% second stage Yvonne 2012-08-02 09:50 [Two-Stage / GS Designs]
- two-stage design power 90% second stageElMaestro 2012-08-02 10:17
  - two-stage design power 90% second stage Yvonne 2012-08-02 11:47
    - two-stage design power 90% second stage ElMaestro 2012-08-02 11:54
- two-stage design power 90% in sample size adaption d_labes 2012-08-02 10:33
  - two-stage design power 90% in sample size adaption ElMaestro 2012-08-02 11:29
    - two-stage design power 90% in sample size adaption Yvonne 2012-08-02 12:06
      - two-stage design power 90% in sample size adaption ElMaestro 2012-08-02 16:59
- Are simulations sufficient? …lenghty post! Helmut 2012-08-02 17:39
  - adjusted alpha = 0.045 d_labes 2012-08-03 11:33
    - adjusted alpha = 0.038 Helmut 2012-08-03 14:26
      - adjusted alpha by sims? d_labes 2012-08-03 15:48
        
        Yeah but, no but, yeah but, no but… Helmut 2012-08-03 16:39
        
        Yeah but, no but ... d_labes 2012-08-07 14:42
        
        Yeah but, no but ... Helmut 2012-08-07 15:14