Bioequivalence and Bioavailability Forum

Dear Srinetram,

in addition to Dan I recommend you the R-package PowerTOST which contains the functions sampleN.scABEL() and sampleN.RSABE() which allows you the sample size estimation for the EMA or FDA recommended methods with arbitrary anticipated CV's and point estimators, aka GMR's.

You will find that your expectation "EMA method requires higher sample size than FDA method" is fulfilled.

But your explanation " ... one have to meet the 95% Upper confidence interval ..." is at least somewhat vague or false if you mean "as compared to the usual 90% confidence intervals".
The reason behind is that the EMA method is more stringent then the FDA. This is best explained by the "implied BE limits". Read Helmut's excellent lectures about sample size planning to get further insight.