1: Anal Chim Acta. 2007 May 22;591(2):239-47. Epub 2007 Apr 7.

Improvement of the decision efficiency of the accuracy profile by means of a
desirability function for analytical methods validation. Application to a
diacetyl-monoxime colorimetric assay used for the determination of urea in
transdermal iontophoretic extracts.

Rozet E, Wascotte V, Lecouturier N, Préat V, Dewé W, Boulanger B, Hubert P.

Laboratory of Analytical Chemistry, Bioanalytical Chemistry Research Unit, Drug
Research Center, Université de Liège, B 36, B-4000 Liège, Belgium.
Eric.Rozet@ulg.ac.be

Validation of analytical methods is a widely used and regulated step for each
analytical method. However, the classical approaches to demonstrate the ability
to quantify of a method do not necessarily fulfill this objective. For this
reason an innovative methodology was recently introduced by using the tolerance
interval and accuracy profile, which guarantee that a pre-defined proportion of
future measurements obtained with the method will be included within the
acceptance limits. Accuracy profile is an effective decision tool to assess the
validity of analytical methods. The methodology to build such a profile is
detailed here. However, as for any visual tool it has a part of subjectivity. It 
was then necessary to make the decision process objective in order to quantify
the degree of adequacy of an accuracy profile and to allow a thorough comparison 
between such profiles. To achieve this, we developed a global desirability index 
based on the three most important validation criteria: the trueness, the
precision and the range. The global index allows the classification of the
different accuracy profiles obtained according to their respective response
functions. A diacetyl-monoxime colorimetric assay for the determination of urea
in transdermal iontophoretic extracts was used to illustrate these improvements.

PMID: 17481415 [PubMed - indexed for MEDLINE]

Related Links

    Using tolerance intervals in pre-study validation of analytical methods to
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2007] PMID:17420025

    Validation of analytical methods based on accuracy profiles. [J Chromatogr A.
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    Improvements in the determination of urea using diacetyl monoxime; methods with
and without deproteinisation. [Clin Chim Acta. 1980] PMID:7428175

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Suppl. 2006] PMID:16700153

    The chemistry of the diacetyl monoxime assay of urea in biological fluids. [Clin 
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