## aproximate n [Power / Sample Size]

Dear Imph,

beside to all what Helmut has told you you may find in the /doc directory of the package a PDF file "BE_power_sample_size_excerpt.pdf" which has some small further informations about the sample size estimation.

You may obtain an approximation of n by using the large sample approximation.

See P. Zhang

“A simple formula for sample size calculation in equivalence studies.”

J. Biopharm. Stat. 2003 Aug;13(3):529-38

This approximate number is in many cases relatively close to the exact value, and is used in PowerTOST as starting value of the iterative search of the sample size.

beside to all what Helmut has told you you may find in the /doc directory of the package a PDF file "BE_power_sample_size_excerpt.pdf" which has some small further informations about the sample size estimation.

You may obtain an approximation of n by using the large sample approximation.

See P. Zhang

“A simple formula for sample size calculation in equivalence studies.”

J. Biopharm. Stat. 2003 Aug;13(3):529-38

This approximate number is in many cases relatively close to the exact value, and is used in PowerTOST as starting value of the iterative search of the sample size.

—

Regards,

Detlew

Regards,

Detlew

### Complete thread:

- Choosing formula for sample size Imph 2021-10-20 11:03 [Power / Sample Size]
- Exact (Owen’s Q) Helmut 2021-10-20 11:36
- Exact (Owen’s Q) Imph 2021-10-20 12:53
- Exact (Owen’s Q) Helmut 2021-10-20 13:26
- Exact (Owen’s Q) Imph 2021-10-24 10:41
- n iteratively from power Helmut 2021-10-24 10:54
- aproximate nd_labes 2021-10-24 19:26

- Exact (Owen’s Q) Willem Talloen 2022-09-01 15:48
- PowerTOST & FDA Helmut 2022-09-01 16:31

- Exact (Owen’s Q) Imph 2021-10-24 10:41

- Exact (Owen’s Q) Helmut 2021-10-20 13:26

- Exact (Owen’s Q) Imph 2021-10-20 12:53

- Exact (Owen’s Q) Helmut 2021-10-20 11:36