Assumptions… [Power / Sample Size]

posted by Rocco_M – Mexico, 2019-09-09 18:35 (1661 d 19:58 ago) – Posting: # 20560
Views: 5,909

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:

UA Flag
Activity
 Admin contact
22,957 posts in 4,819 threads, 1,639 registered users;
102 visitors (0 registered, 102 guests [including 7 identified bots]).
Forum time: 13:33 CET (Europe/Vienna)

Nothing shows a lack of mathematical education more
than an overly precise calculation.    Carl Friedrich Gauß

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