Assumptions… [Power / Sample Size]

posted by Rocco_M – Mexico, 2019-09-09 16:35  – Posting: # 20560
Views: 2,090

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
20,456 posts in 4,296 threads, 1,413 registered users;
online 17 (0 registered, 17 guests [including 12 identified bots]).
Forum time (Europe/Vienna): 20:32 CEST

No one wants to learn from mistakes, but we cannot learn enough
from successes to go beyond the state of the art.    Henry Petroski

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