Two tests and one reference [General Sta­tis­tics]

posted by Helmut Homepage – Vienna, Austria, 2018-06-26 13:13 (824 d 19:44 ago) – Posting: # 18967
Views: 8,659

Hi libaiyi,

» […] the goal is to prove the equivalence of any two of them (T1 and R or T2 and R). Will the CI still determined as 95% or 90%?

If this is a pivotal study (say you want to demonstrate BE of a capsule (T1) and a tablet (T2) to R which is either a tablet or a capsule) IMHO, you should employ Bonferroni’s 95% which preserves the familywise error rate at 1-(1-0.05/2)2=4.9375%. Reason: When both products are approved, based on ABE a patient my switch from R to T1 or from R to T2.
Slightly off topic: Another story would be one test and two references of different regions. If we ignore tourists, we have two different populations of patients. Then we don’t have to adjust α and go with the 90% CI.

» I also want to know how to select the suitable design between latin squares and William design when there exists three treatment, R T1 T2.

That’s a matter of taste. Williams’ designs are variance-balanced even for carryover (which is not part of the model). Hence, some people (see there) prefer them over Latin Squares. BTW, the EMA’s GL states the six-sequence Williams’ design for the story mentioned above.
More important than the design is the evaluation (see this post).

Dif-tor heh smusma 🖖
Helmut Schütz

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

Complete thread:

 Admin contact
21,081 posts in 4,397 threads, 1,468 registered users;
online 5 (0 registered, 5 guests [including 2 identified bots]).
Forum time: Monday 08:58 CEST (Europe/Vienna)

A central lesson of science is that to understand complex issues
(or even simple ones), we must try to free our minds of dogma and
to guarantee the freedom to publish, to contradict, and to experiment.
Arguments from authority are unacceptable.    Carl Sagan

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