Mea culpa! [Power / Sample Size]

posted by Helmut Homepage – Vienna, Austria, 2020-05-04 14:40 (1424 d 17:51 ago) – Posting: # 21395
Views: 7,990

Hi ElMaestro,

❝ the powerTOST package is excellent …


THX!

❝ … and I am not myself a very experienced user (yet) as I tend to rely on much less reliable code of my own making :-D


Sure. In line what Jaime once stated:

Never trust in any piece of software you haven't written yourself
(and even then you should be cautious…)


❝ So forgive me I am asking: I think the OP implied a partial replicate. TRR/RRT/RTR is not 3x6x3 but rather 2(trts)x3(seqs)x3(pers), …


Oops! You are absolutely right.

❝ ❝ 3 way crossover, reference replicate


❝ … is there a reason to plug in 3x6x3 in your code?


I screwed up! Of course, not a 3-period Williams’ design. Hence,

library(PowerTOST)
round(100 * CVfromCI(lower = 0.9625, upper = 1.2511,
                     n = 41, design = "2x3x3"), 2)

and

Unbalanced 2x3x3 design. n(i)= 14/14/13 assumed.
[1] 42.97

That’s reasonably close to the 42.6% given in the PAR. Sorry for the confusion caused!

@Alyssa: Can you please check whether the expanded limits are also given in the PAR? Based on CVwR 42.6% they should be close to

round(100 * scABEL(CV = 42.6 / 100), 1)
lower upper
 73.3 136.4


Dif-tor heh smusma 🖖🏼 Довге життя Україна! [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
22,957 posts in 4,819 threads, 1,636 registered users;
99 visitors (0 registered, 99 guests [including 7 identified bots]).
Forum time: 07:31 CET (Europe/Vienna)

With four parameters I can fit an elephant,
and with five I can make him wiggle his trunk.    John von Neumann

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