Re-testing [Outliers]

posted by Helmut Homepage – Vienna, Austria, 2014-01-08 17:16 (3362 d 05:09 ago) – Posting: # 12151
Views: 13,165

Hi Dan & all,

❝ […] but rather a re-dose study (you administer test and reference in a cross-over design in the outlying subjects together with a certain number of other study participants). However this is only possible for FDA submissions.

See FDA’s guidance, Section VII.C:

[…] deletion of outlier values is generally discouraged, particularly for nonreplicated designs. With replicated crossover designs, the retest character of these designs should indicate whether to delete an outlier value or not. Sponsors or applicants with these types of data sets may wish to review how to handle outliers with appropriate review staff.

I have strong doubts whether the FDA would accept a re-testing study following a replicate study. In Balakotu’s case Subject II might be excluded, but not Subject I. Don’t be tempted to try that without talking to the OGD’s review staff before – keep RTR in mind!
Only fully replicated 4-period studies (RTRT|TRTR) are “fool-proof”.

If you are interested in a statistical approach (not recommended for beginners):

Schall R, Endrényi L, Ring A. Residuals and Outliers in Replicate Design Crossover Studies. J Biopharm Stat. 2010;20(4):835–49. doi 10.1080/10543401003618876

Dif-tor heh smusma 🖖🏼 Довге життя Україна! [image]
Helmut Schütz

The quality of responses received is directly proportional to the quality of the question asked. 🚮
Science Quotes

Complete thread:

UA Flag
 Admin contact
22,550 posts in 4,724 threads, 1,606 registered users;
18 visitors (0 registered, 18 guests [including 8 identified bots]).
Forum time: 22:26 CET (Europe/Vienna)

That which is static and repetitive is boring.
That which is dynamic and random is confusing.
In between lies art.    John Locke

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