Bioequivalence and Bioavailability Forum • Power for PE outside the acceptance range

Power for PE outside the acceptance range [Power / Sample Size]

posted by d_labes – Berlin, Germany, 2016-01-13 12:59 (3819 d 21:23 ago) – Posting: # 15821
Views: 14,276

Dear Jay,

❝ ... But what may be the probable reason for such huge difference between post hoc power of Cmax and AUC.

Simple enough: PE for AUC not outside acceptance range.

For Cmax with PE outside acceptance range you could even have a very large number of subjects in your study without rising your post-hoc power:

library(PowerTOST)

power.TOST(CV=0.2101, theta0=1.278, n=18, design="2x3x3")

[1] 0.02239529

power.TOST(CV=0.2101, theta0=1.278, n=102, design="2x3x3")

[1] 0.005853529

power.TOST(CV=0.2101, theta0=1.278, n=1002, design="2x3x3")

[1] 5.443279e-06

On the contrary power is even decreasing.

The post-hoc power is useless because it is a 1:1 function of the BE test.

BE for AUC_t, AUC_inf proven
BE for C_max not proven

Full stop.

(Count up: post 992)

Edit: power.TOST() calls changed to partial replicate design after Helmut's post below

—
Regards,

Detlew

Complete thread:

Post hoc Power Jay 2016-01-08 06:49
- Post hoc Power ElMaestro 2016-01-08 15:07
- Post hoc Power Helmut 2016-01-09 14:21
  - Post hoc Power Jay 2016-01-11 10:59
    - PE outside the acceptance range Helmut 2016-01-11 14:02
      - PE outside the acceptance range Jay 2016-01-13 08:24
        
        Power for PE outside the acceptance ranged_labes 2016-01-13 11:59
        PE at border of the AR: power ≡ 0.05 Helmut 2016-01-13 12:38
        
        PE at border of the AR: power ≡ 0.05 ? d_labes 2016-01-13 13:21
        
        PE at border of the AR: power ≤0.05! Helmut 2016-01-14 01:29
        
        UMP - uniformly more powerful test d_labes 2016-01-15 20:08
        PE at border of the AR: power ≤0.05! zizou 2016-01-24 22:12
        
        Smoothing artifact Helmut 2016-01-25 14:15