ANOVA fixed and random effects [General Sta­tis­tics]

posted by Babe_Ruth – USA, 2019-02-08 19:53 (755 d 09:10 ago) – Posting: # 19891
Views: 3,669

I appreciate the knowledge and perspectives, ElMaestro! I was thinking of writing a "Hi" in my initial post, but thought it would detract from the central questions, haha.

» That might do, but why not crossover? You'd gain information or at least have an opportunity to impress an agency with design complications :-) and you'd potentially have less deficiency letters.

The sponsor specified this fixed-sequence design in their protocol.A little more context regarding this study: Phase I, healthy subjects, with SAD (n=30), food effect (n=12), and MAD (n=24) parts. I don't know why they designed it to have all subjects take the drug under fasted and then fed conditions. I can't think of any advantage fixed sequence over 2 sequence in this study. Have you ever seen instances where one sequence is advantageous over two sequence?

» If you do it your way, then the most straightforward evaluation is a (paired) t-test approach or equivalently a linear model with two fixed effect (Condition, subject). It will give the exact same result.

Interesting, I'll look into this. Lots of terms and names I don't know in your last few paragraphs :D

Typically, I focus on specific PK sections of the study, but I'm working on learning the study design and stats aspects, so I can pull a bigger picture together.

Edit: Also, one last question. Somebody proposed the ANOVA model with terms for treatment condition (Fasted and Fed) as fixed effects, and subject nested within treatment condition (fasted and fed) as a random effect. Does this random effect make sense?

Complete thread:

 Admin contact
21,366 posts in 4,462 threads, 1,493 registered users;
online 9 (1 registered, 8 guests [including 4 identified bots]).
Forum time: Friday 05:04 CET (Europe/Vienna)

The statistician has no magic touch by which
he may come in at the stage of tabulation
and make something of nothing.    W. Edwards Deming

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