Williams design 3-way [Design Issues]

posted by Brus – Spain, 2021-06-10 14:33 (351 d 06:39 ago) – Posting: # 22402
Views: 4,070

Hi Helmut,

» 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.


IMHO, in my 3x4x6 design proposal,


Eeach formulation is administered once per subject, occurs the same number of times in each period, and any formulation is preceded equally often by each of the other formulations. In this way it is a balanced design. What benefit does williams design bring?

» What is your idea behind such a design?

Make a balanced design with as few sequences as possible.

» 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.

Will Simple Latin Square be accepted by EMA assessors? Will my proposal design be accepted by EMA assessors?

Best regards,

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