Yes, but why? [Power / Sample Size]

posted by DavidManteigas – Portugal, 2017-12-28 15:59  – Posting: # 18114
Views: 21,544

Hi all,

I think the answer to the first question of this post is "because you were very pessimistic on your assumptions regarding sample size" which is something very common in BABE trials (at least, this is my perception).

In this case, given your simulations above and the expected probability of approximately 12% of the studies having power greater then 95% having in consideration the initial assumptions, post hoc power means nothing. But if you had 100 studies instead and 90% of the had >95% power although the sample size was calculated assuming expected power of 80%, some questions and conclusions might be drawn from those results, don't you think? From my understanding of the initial question, this was the case found. So I think that they should start by reviewing how they define their assumptions for the sample size, namely why they assume GMR=1.10 instead of the "normal" 0.95/1.05.

Regards,
David

Complete thread:

Activity
 Mix view
Bioequivalence and Bioavailability Forum |  Admin contact
19,817 posts in 4,200 threads, 1,361 registered users;
online 8 (0 registered, 8 guests [including 6 identified bots]).
Forum time (Europe/Vienna): 14:00 UTC

A big computer, a complex algorithm and a long time
does not equal science.    Robert Gentleman

The BIOEQUIVALENCE / BIOAVAILABILITY FORUM is hosted by
BEBAC Ing. Helmut Schütz
HTML5