Bioequivalence and Bioavailability Forum • ethics and power

ethics and power [Power / Sample Size]

posted by Ohlbe – France, 2011-11-01 23:57 (5342 d 11:20 ago) – Posting: # 7578
Views: 9,391

Dear Maestro and D. Labes,

❝ ❝ ❝ But I would not give a cut-off value as futile because I think that a target power of f.i. 0.778 is equal sufficient like 0.8.

❝ ❝ Personally, I would be inclined to think that if regulators want a 90% CI with two decimals then we should consider power in a similar strict fashion since there's an ethics perspective involved.

❝ ❝ ❝ (...) the sensitivity analysis of sample size planning Helmut is not tired to preach every time.

❝ ❝ Yeah, that guy talks a bloody lot doesn't he?

❝

❝ Really. But he should change his target audience to regulatory bodies :cool: .

He will have to change his target to Ethics Committees if they start asking for power to be higher than 80.00 %...

I have always been told that you can't give a result with more digits than whatever you have used to calculate it. To calculate a power of 80.00 % you would need to assume T/R = 0.9500 and an intra CV of, say, 23.45 % from you pilot study... Ridiculous.

El Maestro, I would consider differently the number of decimals expected for 90 % CI (where you have acceptance limits, which we know regulators now consider more and more as "death or life" limits for the product), and for power, where this thread shows that there is no universal acceptance threshold.

Regards
Ohlbe

—
Regards
Ohlbe

Complete thread:

When is a BE study futile? ElMaestro 2011-10-31 09:17
- When is a BE study futile? Dr_Dan 2011-10-31 09:46
  - When is a BE study futile? ElMaestro 2011-11-01 09:59
    - Power in the 2-stage design d_labes 2011-11-01 10:28
- When is a BE study futile? Dr_Dan 2011-10-31 12:55
- When is a BE study futile? Helmut 2011-10-31 14:41
  - When is a BE study futile? vinayshed 2011-11-01 05:59
- Minimum target power? d_labes 2011-11-01 10:04
  - ethics and power ElMaestro 2011-11-01 10:46
    - ethics and power d_labes 2011-11-01 11:28
      - ethics and powerOhlbe 2011-11-01 22:57
        
        ethics and power ElMaestro 2011-11-02 09:27
        
        ethics and power Ohlbe 2011-11-02 11:00
    - ethics and power Dr_Dan 2011-11-01 13:10
      - ethics and power ElMaestro 2011-11-01 13:53
        
        When does power become unethical? Dr_Dan 2011-11-02 10:55
        
        When does power become unethical? ElMaestro 2011-11-02 12:01