Bioequivalence and Bioavailability Forum

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

posted by Yvonne – 2012-08-02 11:50 (5062 d 12:13 ago) – Posting: # 9018
Views: 19,335

Dear all,

Can someone help me with the following question. We are currently planning for a two-stage design (potvin method C).

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 , would a sample size calculation based on 90% power be accepted by the 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 .


Regards,
Yvonne

Complete thread:

• two-stage design power 90% second stageYvonne 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 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