Bioequivalence and Bioavailability Forum • Interim Analysis and Power

Interim Analysis and Power [Two-Stage / GS Designs]

posted by Emrah Soner Özdeş – Turkey, 2014-12-26 09:55 (3832 d 05:03 ago) – Posting: # 14178
Views: 7,659

Herr Schütz;

❝ Please help me understand the details. I get on basis of Cmax:

❝ PE=88.31% and CV=27.5% with N1=24, and assuming balance you'll have a power of about 65% (alpha 5%, GMR 95% as per Potvin and not 88.31%). Where did I go wrong here?

It seems that I need to check my calculations for power value since point estimator and CV values are same with the one you calculated. Could you advice a reliable formula to check my calculations ?

❝ I assume you wrote in your protocol that your way through the decision tree would be dictated by Cmax and not AUCt? You'll be going into stage 2 before declaring success or failure.

No it will be dictated by both Cmax and AUCt. Assuming that both endpoints are outside the 90% CI and power is below 80% for only one endpoint ? What would be the next step ?

Thanks in advance

Emrah

Complete thread:

Interim Analysis and Power Emrah Soner Özdeş 2014-12-24 07:38
- Interim Analysis and Power Helmut 2014-12-24 16:22
  - Interim Analysis and Power Emrah Soner Özdeş 2014-12-25 08:36
- Interim Analysis and Power ElMaestro 2014-12-25 12:32
  - Interim Analysis and PowerEmrah Soner Özdeş 2014-12-26 08:55
    - R-code & some thoughts Helmut 2014-12-26 17:51
      - R-code & some thoughts Emrah Soner Özdeş 2014-12-29 07:49