Bioequivalence and Bioavailability Forum • Decision scheme 'without' power check

Decision scheme 'without' power check [Two-Stage / GS Designs]

posted by d_labes – Berlin, Germany, 2011-10-26 16:51 (5359 d 02:43 ago) – Posting: # 7547
Views: 21,732

Dear ElMaestro,

❝ Alpha2 only kicks in when and if you know you are going into stage 2. Until then it is alpha1 everywhere. That would at least be least my understanding and intuition.

That would mean what in my last scheme hiding the power check step?

If we are going to stage 2 is clear (n_est > n₁).
Calculate sample size with alpha₁ because we here don't know if we are going to stage 2? That would be against my intuition.
if n_est ≤ n₁ -> stop: fail with BE evaluated at alpha₁?

—
Regards,

Detlew

Complete thread:

2-stage design - power evaluation d_labes 2011-10-12 11:10 [Two-Stage / GS Designs]
- No opinions out there? d_labes 2011-10-26 09:14
  - Opinion yes, answer no ElMaestro 2011-10-26 11:15
    - Decision scheme without (?) power check d_labes 2011-10-26 13:00
      - Decision scheme without (?) power check ElMaestro 2011-10-26 13:20
        
        Decision scheme 'without' power checkd_labes 2011-10-26 14:51
        
        Decision scheme 'without' power check ElMaestro 2011-10-26 15:24
        
        Numerical example d_labes 2011-10-26 16:28
        
        Numerical example ElMaestro 2011-10-26 16:49
        
        Potvin C with unsymmetrical alphas d_labes 2011-10-27 14:54
        
        Potvin B, C, or D? Helmut 2011-10-27 22:52
        Two-stage (classical Pocock) and the FDA Helmut 2011-10-31 02:36
- Weirdo paper ElMaestro 2011-11-30 18:04
  - Weirdo paper Helmut 2011-11-30 23:45
    - Weirdo paper ElMaestro 2011-12-01 07:16