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Where did the need for this series of ISO Standards originate?
The validation and verification of an analytical method will ensure that our results are reliable and robust due to the standardization and verification of the methods used in the laboratory. It will also allow the team in charge of carrying them out to be evaluated and challenged.
The ISO 16140 series of standards is a response to the standardization of the two processes and consists of six parts. Each of them will contain valuable information for method validation and verification processes.
- In the 1st part we will be able to look up the definitions of the terms that will help us to better understand the other parts.
- The 2nd part outlines the protocol to be followed for the validation of a registered alternative method.
- While the 3rd part covers the protocol for verifying a reference method or a validated alternative method in a single laboratory.
- Parts 4 to 6 include the protocols for the validation of in-house methods, for the interlaboratory factorial validation of non-registered methods, and for the validation of alternative methods for confirmation and typing, respectively.
For validation, the part to be consulted will depend on several factors, such as whether it is a qualitative or quantitative method, whether it is a reference or alternative method, and also whether the method is registered or not. The last variable would be if it is intended to be performed in a single laboratory or in multiple laboratories.
Depending on our answers to each variable, we should look at parts 2, 4 or 5.
However, if what we are interested in is verification, we should simply refer to part 3 of the series.
The scope of this series of ISO Standards covers not only human food and animal feed samples, but also environmental samples from production and primary production sites.
Is validation the same as verification?
These are concepts that may be confused or taken as the same, but they are not.
On the one hand, a validation establishes the performance characteristics for a method that meets the performance requirements for a specific use and are equivalent to the reference method.
On the other hand, verification demonstrates that a method implemented by a laboratory performs according to specifications which are usually determined during the methodvalidation, and is therefore suitable for its intended use.
In other words, the performance of a method is validated, and its proper use is verified.
In order to use a method in a laboratory, a validation followed by verification must be performed.
The validation is usually carried out by interlaboratory studies, and the information from these studies will help us to choose the food items necessary to perform the verification.
The verification consists of 2 stages; the first is the implementation verification and the second is the food item verification.
During the first one, we will demonstrate that the laboratory can perform the method correctly. During the second, the laboratory shows that it can analyze the items it declares within its scope.
I want to implement a method in my laboratory. How can I perform the verification?
The procedure for verification will depend on the type of method, whether it is qualitative or quantitative.
For qualitative methods, the estimated LOD50 or eLOD50, which refers to the level of detection with a 50% probability of detection, should be determined for both the implementation verification and the item verification. The difference between one verification or another will be found in the items to be selected for each one.
On the other hand, for quantitative methods, only the standard deviation for intralaboratory reproducibility or SIR will be determined for the implementation verification.
For the item verification, however, only the estimated deviation or eBias needs to be determined.
When the acceptability criterion is met for each of these characteristics, the method would be successfully verified.
To learn more about ISO 16140-3 and this series of Standards, you are invited to watch our CondalabTalk Verify alternative methods in your laboratory according to ISO 16140-3.
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