Hel­mert trans­for­ma­tion? [Software]

posted by Helmut Homepage – Vienna, Austria, 2022-04-04 14:23 (53 d 03:44 ago) – Posting: # 22907
Views: 652

Hi Shatha,

» I have 2 treatments, 2 periods, crossover, multiple dose, steady state study.
» The last 3 pre-dose concentrations should be used for steady state verification for each subject in each period.

You can’t verify anything in science.
In statistics you can only try reject a properly stated [image] null hypothesis – which is in your case what? Any test at level \(\small{\alpha}\) has an unavoidable false positive rate. Do you want to exclude \(\small{(100\times\alpha)\%}\) of subjects although they are in (pseu­do) steady state?

» I need your help to perform this verification using Helmert transformation method …

Do you have a reference demonstrating its application in PK? Never came across this approach in 40+ years. See there why statistical tests are nonsense – essentially because we don’t have a proper null.

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