NCA with bear? [RSABE / ABEL]

posted by yjlee168 Homepage – Kaohsiung, Taiwan, 2015-03-09 15:24 (2631 d 06:37 ago) – Posting: # 14555
Views: 25,978

Dear Astea,

» [...] But if it is so, why can't we use NCA data received manually for the latest statistical analyses in BEAR?
» I tried to use NCA data contained unequal numbers of subjects in different periods and BEAR didn't show errors while doing statistics.
» For example, we omit one of the period from the study for the N'th subject. Will the statistics compilated by BEAR be correct in such a case?

Really? I have no idea right now. No error with omitting one of the periods from a subject? I am not sure about that. A very good question.

» By the way, what is the reason for which BEAR couldn't calculate NCA for subjects with all zero concentrations in one of the period? In my mind, all individual pharmacokinetic parameters should be calculated independently for each period? :confused:

You are right about the procedures of NCA. However, when doing NCA, it also calculates some other parameters. For example, clearance (CL) is calculated with Dose*F/AUC0-inf. For all zero concentrations, AUC0-inf is zero. So it crashes. Also to estimate the terminal phase elimination rate constants (kel), it requires none-zero data from terminal phase to perform linear regression (to get a slope). It certainly stops the run at this step too.

» And the last question: am I right when thinking that for calculation CI of Cmax/AUC0t I can simply change the columns AUC0INF and lnAUCOINF for Cmax/AUC0t and ln Cmax/AUC0t respectively?

Smart way. It should work well. You have to remember to change the name of parameters with all output files.

All the best,
-- Yung-jin Lee
bear v2.9.1:- created by Hsin-ya Lee & Yung-jin Lee
Kaohsiung, Taiwan
Download link (updated) -> here

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