Inter-laboratory, time, and fitness-for-purpose aspects of effective validation Original Research Article

This paper reviews current approaches to validation of analytical chemical methods. It identifies some shortcomings of existing validation schemes such as insufficient coverage of variability in space or time, and mismatches between validation criteria and intended use of the method, e.g. the use in regulatory control. A general statistical modelling approach for combining different aspects of validation is recommended, and illustrated with an example. This type of modelling, based on components of variation, is advocated as the basis for the development of new statistically underpinned validation schemes which integrate current validation and quality assurance activities.