Hello Anon,
From my perspective, I believe the explanation of Established and Standardised tests versus Established and Non-Standardised tests are described in Section 7 of the GHTF Document N7. I would not put too much emphasis on the examples, because already this was written back in 2009/2010, published in 2012, which is already 10 years ago. In the IVD world, some tests 10 years could be equated as a lifetime as the development progresses relatively quickly. Though I would agree there is still some ambiguity and interpretation which could be made as standardised versus non-standardised. Reading through the GHTF N7 document one difference is the non-standardised test results can not be used interchangeably between devices. I also read standardised versus non-standardised is having say chemistry-type tests which are all done the same way versus assays or genetic which can be done different ways, i.e. immuno, PCR, FiSH. I think you will have differing opinions in that regard as well. And then of course do not forget the third one which is a Novel type of assay.
For me stating whether a tests assay is Established and Standardised or Established and Non-standardised (or Novel) is made through the scientific validity of the test analyte. This is talked about and described in both of the documents which you reference. In addition, this is a component needed as part of the EU IVDR performance evaluation as well. From my perspective, an Established and Standardised test would have acceptance criteria clearly defined in established documents, such as ISO standards or Common Specifications (for the EU). Whereas maybe Non-standardised tests there are industry accepted criteria or values for the test which might be published by a healthcare organisation, e.g. ACC. As always it depends on the IVD test assay, but I would use the examples in the GHTF N7 document loosely and rely more on how you define your test in the scientific validity. Ultimately, the performance evaluation needs to prove the "trueness" of a test, so established standards is easier to do (and easier to support in scientific validity) than say a novel test where there is no defined accepted results or trueness. Read the end of Section 7.1 in the GHTF document where it talks about having sufficient clinical evidence - this is where standard test methodologies help support clinical evidence.
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Richard Vincins ASQ-CQA, MTOPRA, RAC
Vice President Global Regulatory Affairs
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Original Message:
Sent: 11-Jul-2022 00:35
From: Anonymous Member
Subject: Standardized test?
This message was posted by a user wishing to remain anonymous
Hi All,
I'm looking for some assistance in categorizing an IVD product as per GHTF/SG5/N7:2012 and MedTech Europe Clinical Evidence Requirements for CE certification under the IVDR (second edition, November 2021) in terms of Established & Standardized vs Established and non-Standardized.
The definitions of these groups has caused me a little confusion as i believe the product i refer to could perhaps fall within either group. The IVD I refer to is a Tissue Typing assay (HLA) assay for the purposes of identifying best matches for transplantation or transfusion.
Such devices are well established. In terms of definition as a standardized test:
1) An international reference material exists in the form of the IMGT reference database for such devices.
2) More than one commercial test exists
3) Standardized devices/tests produce equivalent results for the analyte regardless of the method/manufacturer.
Where i have been thrown somewhat is the definition of non-standardized tests in the GHTF document which states as an example of a non-standardized test: ".....and cell markers (e.g. CD4, T-cells)."
Would appreciate some opinion on whether the IVD i refer could be considered standardized?
Much appreciated