Validation: concept, & considerations. Beni Kaufman. Will be presenting:. Review The concept Validation Components and their measurement experimental design of PCR validation Process vs. Modular validation. References:. Guidance for Industry: Bioanalytical Method Validation.
U.S. Department of Health and Human Services, Food and Drug Administration (FDA), Center for Drug Evaluation and Research (CDER), Center for Veterinary Medicine (CVM) May 2001
Analytical Environmental Immunochemical Consortium (AEIC) Biotech Consensus Paper; S. Charlton, R. Giroux, D. Hondred, C. Lipton, K. Worden
Discuses components… avoid criteria!
Selectivity may be affected by:
do not use r2774, 02-08-2006, 15Hr 58Min.mxp
Measured by error rate:
% false positive = False positives/ # of negatives
% false negative = False negatives/# of positives
% Recovery =100 (observed/actual)
the deviation of the mean from the true value)
Two concepts of sensitivity:
In PCR the dose response is derived from the amplification efficiency - We optimize the assay for a maximal dose response (~100% amp. Efficiency)
Limit of quantification (LOQ), The lowest amount of target analyte that can be quantified with acceptable levels of precision and accuracy.
The LOD will be lowest spike detected with an acceptable confidence level.
The LOQ will be the lowest spike that can be differentiated from zerowith an acceptable confidence level
Effectiveness is measured as changes in the precision or accuracy:
Where the Relative Standard Deviation of Reproducibility (RSDr) is given as:
RSDr = 2(1-0.5lnC) ~ 2C-0.1505
(C= concentration or quantity) And
HORRAT = RSDr(observed)/RSDr(expected)
HORRAT is expected to be close to 1
Usually part of the assay optimization, prior to the validation process.
Can take away some of the edge…
(For example: from 2% to 0.01% at -0.5X increments).
(3 different dates (?) Astrological effect)
(… from 2% to 0.01% at -0.5X increments).
The testing process is made of a number of consecutive steps, all can be validated, some have to be validated
The recognition that many of the applications – steps, in the testing process require independent validation of their function
For better efficiency
Brought about the idea of Modular Validation
A. Holst-Jensen, J-AOAC, 1995
Validate each step (module).
Once, validated, different modules can be combined in to a process that no longer require validation
DNA is DNA!?
IT IS NOT.
All affect the out come of the testing process, therefore, the validation is of the whole process and only in the context of the given matrix, instrumentation, & standards…
Any deviation…will require