Bioequivalence and Bioavailability Forum • T/R ratio for estimation of sample size in BE study of NTI drugs

T/R ratio for estimation of sample size in BE study of NTI drugs [Power / Sample Size]

posted by mahmoud-teaima – 2017-10-24 21:18 (2742 d 12:14 ago) – Posting: # 17916
Views: 9,040

Salam to all,
Pease, advise me about what is the best T/R ratio to be used for estimating sample size for a BE study of NTI drugs? knowing that the GL to be followed set the 90% CI acceptance range to (90-111.11) for Cmax if a "2x2x2" design be followed.
I'm confused to use T/R ratio of 0.95 or 0.975?!

+++++++++++ Equivalence test - TOST +++++++++++

            Sample size estimation

-----------------------------------------------

Study design:  2x2 crossover 

log-transformed data (multiplicative model)



alpha = 0.05, target power = 0.8

BE margins = 0.9 ... 1.1111 

True ratio = 0.95,  CV = 0.0945



Sample size (total)

 n     power

40   0.808788 



+++++++++++ Equivalence test - TOST +++++++++++

            Sample size estimation

-----------------------------------------------

Study design:  2x2 crossover 

log-transformed data (multiplicative model)



alpha = 0.05, target power = 0.8

BE margins = 0.9 ... 1.1111 

True ratio = 0.975,  CV = 0.0945



Sample size (total)

 n     power

20   0.820356

Greetings.

—
Mahmoud Teaima, PhD.

Complete thread:

T/R ratio for estimation of sample size in BE study of NTI drugsmahmoud-teaima 2017-10-24 19:18
- T/R ratio for estimation of sample size in BE study of NTI drugs Helmut 2017-10-24 23:15
  - T/R ratio for estimation of sample size in BE study of NTI drugs ElMaestro 2017-10-25 12:34
    - T/R ratio for estimation of sample size in BE study of NTI drugs nobody 2017-10-26 14:03
      - Defaults in PowerTOST d_labes 2017-10-26 14:49