Will There Be Any Interfering Substances

The extent of validation required will depend on the nature of the intended analytical outcomes. Is the method quantitative (i.e., to allow a measure of quantity of some characteristic of the sample, whether it be active ingredient, impurities, or excipient) or is the method simply a determination of what is present (qualitative) In the forensic environment, both qualitative and quantitative data will most likely be required therefore, it is advisable to ensure that the validation covers both aspects. The extent to which validation is conducted and the parameters that should be included have been the subject of several guidance documents produced by a variety of industrial committees and regulatory or advisory bodies. 

ISO/lEC 17025 includes a section (2005 Section 5.4 Test and Calibration Methods and Methods Validation) dedicated to the test and caUbration of methods including method validation. Much of the material already covered by the ICH and FDA is again discussed, as is imcertainty in measurement, which will be discussed in this chapter in more detail later. Emphasis is placed on continuous review of validation data to verify that the intended purpose of the method is still being achieved. Table 8.1 can be used as a guideUne for the required validation elements. 

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