Assumptions… [Power / Sample Size]

posted by Rocco_M – Mexico, 2019-09-09 16:35 (496 d 12:53 ago) – Posting: # 20560
Views: 3,739

Gracias and sorry for confusion. Here is what I think I am not getting. When you run a FIM, you do not have two populations. You have a treatment and (perhaps) a control. So if you have a geometric CV, say, CV1 calculated from that one treatment sample in the FIM. [It is not pooled variance, is it? There is only one sample] there and then use it to design a parallel follow-up, do you need to assume that the CV of the other arm, call it CV2, is equal to CV1, and then CVp = pooled(CV1,CV2) as input into sample size formula, eg, sampleNTOST?

Much apology if I am missing this point. I do not seem to understand what are the components of the pooled variance that go into the sample size computation.

Complete thread:

Activity
 Admin contact
21,303 posts in 4,441 threads, 1,487 registered users;
online 5 (0 registered, 5 guests [including 4 identified bots]).
Forum time: Monday 04:29 CET (Europe/Vienna)

I believe there is no philosophical high-road in science,
with epistemological signposts. No, we are in a jungle
and find our way by trial and error,
building our road behind us as we proceed.    Max Born

The Bioequivalence and Bioavailability Forum is hosted by
BEBAC Ing. Helmut Schütz
HTML5