Bioequivalence and Bioavailability Forum • two-stage design power 90% in sample size adaption

two-stage design power 90% in sample size adaption [Two-Stage / GS Designs]

posted by ElMaestro – Denmark, 2012-08-02 13:29 (4707 d 08:46 ago) – Posting: # 9021
Views: 15,063

Hi Yvonne and dlabes,

❝ They argue that the same may take place if the target power is changed. Let me cite: "In particular, we have not considered cases where the desired power used in the method is anything other than 80%. Increasing the power used in the methods from 80 to 90% would be expected to have similar direction of effect as decreasing the GMR used in the methods from 0.95 to 0.90".

They are right. The alpha may go a little up.
Example: T/R=0.9 at CV=0.3 and N1=24 (method B). Alpha is around 0.0529 (Montague's paper) with target power 0.8 but with target power 0.9 alpha increases to 0.0543 (1 million sims).

—
Pass or fail!
ElMaestro

Complete thread:

two-stage design power 90% second stage Yvonne 2012-08-02 09:50
- two-stage design power 90% second stage ElMaestro 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 adaptionElMaestro 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