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Hi,
I am using WinNonlin version 5.2.There are four methods in the NCA
settings tab of the Model options dialogue for the calculation of area
under the curve (AUC) i.e Linear Trapezoidal, Linear trapezoidal with
Linear/Log Interpolation, Linear/Log trapezoidal and Linear Up and Log
down method.
Can any one suggest me the criteria/ ponits to consider for the
selection of the method of calculation of AUC, among four. Is there
any reference for the same??
Thanks in Advance and with regards,
Sharath P
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Dear Sharath,
Kindly refer WinNonlin(R) User's Guide "Noncompartmental analysis
model" options (page nos ~164 to 170) to answer your questions.
Regards
Venkatesh
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The following message was posted to: PharmPK
Dear Sharath
For the log-trapezoidal rule the you underlying assumption is that the
plasma concentration decline mono-exponentially between two measured
concentrations. The method is successful for descending data thus, may
be preferable for drugs with longer half life or for the decreasing
concentrations (down swing) in plasma level time curve. However, since
to calculate the accurate AUC, the permitted bias is 2% the calculation
of AUC with linear trapezoidal rule is usually acceptable.
Nadeem Irfan Bukhari
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The following message was posted to: PharmPK
Dear Nadeem!
> [...]. However, since to calculate the accurate AUC, the
> permitted bias is 2% the calculation of AUC with linear
> trapezoidal rule is usually acceptable.
>
Bias to what?
Where do you get this 2% from?
Best regards,
Helmut
Ing. Helmut SchAtz
BEBAC - Consultancy Services for
Bioequivalence and Bioavailability Studies
Neubaugasse 36/11
1070 Vienna, Austria
e-mail helmut.schuetz.at.bebac.at
web http://bebac.at/
contact http://bebac.at/Contact.htm
forum http://forum.bebac.at
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The following message was posted to: PharmPK
Dear Nadeem!
> [...]. However, since to calculate the accurate AUC, the
> permitted bias is 2% the calculation of AUC with linear
> trapezoidal rule is usually acceptable.
>
Bias to what?
Where do you get this 2% from?
Best regards,
Helmut
Ing. Helmut SchAtz
BEBAC - Consultancy Services for
Bioequivalence and Bioavailability Studies
Neubaugasse 36/11
1070 Vienna, Austria
e-mail helmut.schuetz.-at-.bebac.at
web http://bebac.at/
contact http://bebac.at/Contact.htm
forum http://forum.bebac.at
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It appears the student is confused which is quiet normal in
pharmacokinetics otherwise calculation of AUC value does not require
computation of percentage bias.
s.o.o
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The following message was posted to: PharmPK
Dear Nadeem!
> [...]. However, since to calculate the accurate AUC, the
> permitted bias is 2% the calculation of AUC with linear
> trapezoidal rule is usually acceptable.
>
Bias to what?
Where do you get this 2% from?
Best regards,
Helmut
Ing. Helmut SchAtz
BEBAC - Consultancy Services for
Bioequivalence and Bioavailability Studies
Neubaugasse 36/11
1070 Vienna, Austria
e-mail helmut.schuetz.-at-.bebac.at
web http://bebac.at/
contact http://bebac.at/Contact.htm
forum http://forum.bebac.at
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