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Dear Sir,
what should one do if no peak or concentration less than LLOQ occures
between two measurable concentrations?
Should we consider that as 0.000 or as Missing Samples for AUC
calculation.
Kindly let me know this at your earliest at deshmukh.trupti.-at-.gmail.com
Thanks
Trupti
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The following message was posted to: PharmPK
Dear Trupti,
First of all, the values must be confirmed. Wasn't it any equipment
failure
or process problem?
Best regards,
DIOGO DE O. SILVA
Doutor em Ciencias Farmaceuticas
Quimico Industrial
(11)82393095
DYEDRA Servicos Cientificos Ltda.
Empresa reconhecida pelo CRQ-IV Regiao/SP
CNPJ: 05.767.019/0001-81
Sao Paulo - SP, Brasil
www.dyedra.com
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Dear Trupti,
Do not consider it as missing sample. Missing sample has altogether a
different meaning. I think you can repeat analyse in duplicate the
said sample along with previous and next sample point for confirming
value. Then only you can take some decision on it.
Dr. Mandar Mote
Head Bio-analytical
CRO
Cadila Pharmaceuticals Ltd.
Ahmedabad.
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HI,
This could be an analytical error, if you have SOP for repeat
analysis then move ahead with that.
Or the one way out is consider it as 0.0 and analyze with software
for AUC calculation////// I suppose no problem should encounter.
Hiren
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The following message was posted to: PharmPK
It could happend due to a certein reason. In this case, it is better
to treat that timepoint as missing sample than 0.000, because
WinNonlin can use measurable points to get AUC.
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Dear Trupti,
It could be a sample processing error or instrument malfunction. As
per my knowledge goes we should not consider it as 0 or missing
sample. Better to do repeat analysis of that sample in duplicate
along with its above and below time point sample to confirm the
correctness of the analysis provided if you have sufficient sample
volume.
Other wise we cann't do anything other than putting it as bad
chromatogram.
If you use 0.0 conc.for calculation you will get a different value
other than the actual.
hope this helps you
Rajareddy kallem
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The following message was posted to: PharmPK
It could also be a pre analytical error--incorrect labeling, incorrect
sampling time. Do not always assume it is an analytical error.
Ed O'Connor, PhD
Technical Director, Immunoanalytical
Tandem Laboratories
115 Silvia Street
West Trenton, New Jersey
609-228-0243
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Dear Sir,
what should one do if no peak or concentration less than LLOQ
occures between two measurable concentrations?
Should we consider that as 0.000 or as Missing Samples for AUC
calculation .
Kindly let me know this at your earliest at deshmukh.trupti.-at-.gmail.com
Thanks
Trupti
Back to the Top
The following message was posted to: PharmPK
Investigate.
1) Rule out Pre analytic errors
a) query the clinic or instudy site
2) Look for evidence of:
a) circulating target ( receptors, platelets?)
b) additional compartment
c) circulating antibody
3) check for evidence of an analytical error
a) wrong sample
b) incorrect handling
4) Reassay going back to the original sample
Ed O'Connor, PhD
Technical Director, Immunoanalytical
Tandem Laboratories
115 Silvia Street
West Trenton, New Jersey
609-228-0243
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