Accepted time deviations in Ambulatory PK intervals [Regulatives / Guidelines]
Hi ElMaestro and Researcher101,
» As I see it, one can make a case for saying that the way to deal with time point deviations should be API-specific as well as time-specific.
Agree. The later in the profile, the less critical deviations are.
» Some CROs define a window in terms of time (for each time point)…
See this post and followings. I don’t comprehend why too early sampling should be performed. PK calculations (regardless whether by NCA or by modeling) should always be performed based on the actual time points – otherwise the estimates will be biased.
Extremely nasty in modeling. Both OLS and maximum likelihood approaches require that the independent variable is free of any error. It’s a misconception that errors in the independent variable only increase the residual error. If one wants to deal with that, it get’s really, really tricky (
orthogonal regression, where the selection of appropriate weights is black magic).
» As I see it, one can make a case for saying that the way to deal with time point deviations should be API-specific as well as time-specific.
Agree. The later in the profile, the less critical deviations are.
» Some CROs define a window in terms of time (for each time point)…
See this post and followings. I don’t comprehend why too early sampling should be performed. PK calculations (regardless whether by NCA or by modeling) should always be performed based on the actual time points – otherwise the estimates will be biased.
Extremely nasty in modeling. Both OLS and maximum likelihood approaches require that the independent variable is free of any error. It’s a misconception that errors in the independent variable only increase the residual error. If one wants to deal with that, it get’s really, really tricky (
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Dif-tor heh smusma 🖖
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Dif-tor heh smusma 🖖
Helmut Schütz
![[image]](https://static.bebac.at/img/CC by.png)
The quality of responses received is directly proportional to the quality of the question asked. 🚮
Science Quotes
Complete thread:
- Accepted time deviations in Ambulatory PK intervals Researcher101 2020-11-20 17:59 [Regulatives / Guidelines]
- Accepted time deviations in Ambulatory PK intervals ElMaestro 2020-11-21 10:08
- Accepted time deviations in Ambulatory PK intervals Researcher101 2020-11-22 11:52
- Accepted time deviations in Ambulatory PK intervalsHelmut 2020-11-23 11:49
- Accepted time deviations in Ambulatory PK intervals ElMaestro 2020-11-21 10:08