Williams design 3-way [Design Issues]

posted by Helmut Homepage – Vienna, Austria, 2021-06-09 17:48 (346 d 16:03 ago) – Posting: # 22399
Views: 4,169

Hi Brus,

» I have a question on this topic that you mentioned a long time ago: […]

Please read the entire thread. What I posted in 2007 is obsolete. See also this article.

» According to what you said, 6 sequences had to be done with a 3-way study to get balanced sequences on the two 2x2 tablets. But, with following approach, balanced sequences would also be achieved:
»
» ABC
» BAC
» CAB
» CBA

That’s not balanced for carryover. However, since we cannot correct for unequal carryover anyway (see there), we have to avoid it by design, i.e., sufficiently long washouts between treatment periods.

» It's possible? What problems would it have?

What is your idea behind such a design? Actually a simple Latin Square (ABC|BCA|CAB) would do as well. If you want to make European assessors happy, opt for the 6-sequence Williams’ design.

Most important: Evaluate the study by the ‘Two at a Time’ approach.

» It is not williams square design, right?

Correct.

Dif-tor heh smusma 🖖 [image]
Helmut Schütz
[image]

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

Complete thread:

UA Flag
Activity
 Admin contact
22,091 posts in 4,630 threads, 1,566 registered users;
online 126 (0 registered, 126 guests [including 124 identified bots]).
Forum time: Sunday 09:51 CEST (Europe/Vienna)

Competence, like truth, beauty and contact lenses,
is in the eye of the beholder.    Laurence J. Peter

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