What are 'validation' and 'regulatory acceptance' of alternative methods and why are these formal processes sometimes necessary?
The use of methods (a generic term covering descriptions such as assay, test, technique, tool, strategy, approach etc.), that are not confirmed as suitable for a specific purpose, may give unreliable and irrelevant results. This leads to waste of time, money and resources, including animal lives and may create data that are misleading or incorrect. In addition, this may slow down discovery, and could have serious consequences for consumer protection and workers' safety (for example, if the assay is used for the assessment of the safety of chemicals).
It is therefore of utmost interest to a researcher to ensure that the methods that are used are fit for the purpose.
Scientific research and methods used in research are continually evolving and improving. Methods developed in, and for, basic research are typically built to obtain answers to unique or novel questions. Therefore, these methods are "tailor-made" for a specific scientific purpose for one-time use. However, their fitness to address the question at hand needs to be confirmed one way or another.
The assessment of their validity can take a number of forms. These include general knowledge of the method, the scientific principles on which it is based, historical data from using the method and the use of so-called pilot studies (when using in vivo (animal) methods) with smaller numbers of animals before embarking on a full scale study.
The validity of the used methods is further scrutinised during scientific peer-reviews when the results are presented for publication in scientific journals.
Due to the uniqueness of the questions in the area such as basic research, a 'formal validation process' is in most cases not practical and would potentially result in unnecessary animal use, due to the fact that the results of such a validation would not necessarily be applicable to the next novel question. However, in the area of regulatory testing a formal validation is often a necessity.