ANOVA fixed and random effects [General Sta­tis­tics]

posted by Babe_Ruth – USA, 2019-02-08 19:53  – Posting: # 19891
Views: 1,805

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?

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