S × F interaction [Design Issues]

posted by Helmut Homepage – Vienna, Austria, 2023-06-07 12:34 (116 d 18:36 ago) – Posting: # 23580
Views: 530

Hi Brus,

❝ I don't understand the subject-by-formulation effect, …

You are not alone.

❝ … can it only be studied in full replicated designs?


❝ If the subject-by-formulation effect is the change between test and reference difference means from one subject to another, in a 2x2 design it should be possible to study it. Right?

No. In a 2×2×2 crossover we have already aliased effects (are victims of confounding). See this article.
Adding S × F will not work. Didn’t try it yet. Either you get zero degrees of freedom in a fixed effects model or a mixed-effects model will collapse.

❝ And in that case it could also be measured in partial replicate. Right?


Dif-tor heh smusma 🖖🏼 Довге життя Україна! [image]
Helmut Schütz

The quality of responses received is directly proportional to the quality of the question asked. 🚮
Science Quotes

Complete thread:

UA Flag
 Admin contact
22,763 posts in 4,775 threads, 1,628 registered users;
10 visitors (0 registered, 10 guests [including 2 identified bots]).
Forum time: 07:11 CEST (Europe/Vienna)

The object of statistics is information.
The objective of statistics is the understanding of information
contained in data.    Irwin and Marylees Miller

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