Bioequivalence and Bioavailability Forum

Power<50% [Power / Sample Size]

posted by BEQool  – 2024-03-01 15:26 (420 d 00:45 ago) – Posting: # 23887
Views: 2,860
(edited on 2024-03-01 15:36)

❝ If any of the metrics shows power <50%, the study will fail (see this article).

Hello, is the statement above always true?

For example, in a hypothetical (and very unrealistic ) scenario for Cmax with PE=95%, CV=110%, 36 subjects in a 2x2x3 design we get the following 90% CI:
CI.BE(pe=0.95,n=36,design="2x2x3",CV=1.1)
   lower    upper
0.701628 1.286294

Widened acceptance limits are (the maximum ones):
scABEL(CV=1.1)
    lower     upper
0.6983678 1.4319102

So we pass the study although the power is <50%:
power.scABEL(theta0=0.95,n=36,design="2x2x3",CV=1.1)
  0.23718

Why do we pass the study if the power is below 50%?

BEQool

Complete thread:

• Sequential Sample Size and Power Estimate in R xpresso 2023-09-19 13:40 
  • IUT Helmut 2023-09-19 14:04
    • IUT xpresso 2023-09-19 14:18
      • power is analytically accessible Helmut 2023-09-19 15:46
    • Power<50%BEQool 2024-03-01 14:26
      • Power<50% Helmut 2024-03-01 14:44
        • Power<50% BEQool 2024-03-01 23:02