Are the Metrology Vocabulary (JCGM VIM) and the ISO and CLSI Vocabulary for Medical Laboratories Divergent?
Round 1
Reviewer 1 Report
Comments and Suggestions for AuthorsThis article is devoted to the analysis of an important problem of metrology – the problem of the unity of terminology in different documents, standards, recommendations. The problem exists all over the world, especially at the level of terminology in different countries, since linguistic differences of peoples and historical traditions leave their impact. It is well known problem, old problem, not new. The most correct approach is to organize global international conferences of specialists from all or most countries of the world, based on the results of which a unified opinion on the terminology and units of measured quantities is formulated, as was once done with the International System of Units. The opinions of individual private specialists are important here, but cannot be decisive, since they have a subjective component.
In this aspect, the article is contradictory. On the one hand, it discusses an important problem of terminology using specific examples from documents. On the other hand, individual topical issues, terms, concepts and definitions are highlighted, but there is no general systemic coverage of the problem. In particular, one of the problems is the dominant use of English in terminology, but it is known that in the English language, the polysemy of words is its highlight, its specialty, its basis. However, scientific (not necessarily metrological) terminology must be strictly unambiguous. For example, in our country, measurement error is considered separately as incorrect operator actions, and measurement inaccuracy, which contains a random and systematic component arising due to the imperfection of measuring devices and methods. These are different concepts (error and inaccuracy), but in the English-language metrological terminology, measurement error dominates. However, the author does not consider this and many other similar questions. Moreover, the author presents his own opinion as the most correct. On some questions I can agree, on others - not. When reading the article, the author's selectivity and methodology are not clear.
Therefore, one of the main my comments: the materials and methods section is composed incorrectly, in my opinion. Here I would like to see what methodology the author used to perform his analysis. How did he evaluate the terminology discrepancies and errors? Is the author expressing his personal opinion or did he use some well-founded and generally recognized scientific approach to the analysis? Different specialists may have different views on the problem... That is why the Materials and Methods section exists. It is to explain the chosen tool. However, the presented section is essentially a continuation of the Introduction section and explains the situation, but does not provide a methodology for its analysis. It needs to be rewritten.
It would also be correct to collect and present the problematic issues separately, and to provide a separate section "Author's opinion". Many sections now are presented as the mixed composition of the situation and the author's opinion. In the article there are also no references to the publications of other authors, to university textbooks, to dictionaries, etc., where metrological terminology is also given and discussed. It is not explained what the known position of other authors is on the controversial issues under discussion. In a serious analytical article, it is important to present different opinions.
Author Response
Reviewer 1's remarks are important, allowing us to better clarify the nature of the grant and its methodology.
Comments 1
The opinions of individual private specialists are important here, but cannot be decisive, since they have a subjective component. In this aspect, the article is contradictory. On the one hand, it discusses an important problem of terminology using specific examples from documents.
Response 1
The article contains not only opinions, but a report on recent experience in discussing various papers. That is why it originates from specific examples, not from a general analysis of the problem.
Comments 2
On the other hand, individual topical issues, terms, concepts and definitions are highlighted, but there is no general systemic coverage of the problem. In particular, one of the problems is the dominant use of English in terminology, but it is known that in the English language, the polysemy of words is its highlight, its specialty, its basis.
Response 2
The polysemy of the English language is certainly a real problem. However, today technical standards originate in English and are translated only later and not in all cases. ISO itself provides the definition for each word. The article does not get into language issues, but simply assumes that there is a hierarchy of sources, in which the Vocabulary produced by BIPM is at the top, although it is itself evolving and being discussed. At the level immediately below for medical laboratories stands ISO 15189, below that all other documents, including CLSI guides.
Comments 3
These are different concepts (error and inaccuracy), but in the English language metrological terminology, measurement error dominates. However, the author does not consider this and many other similar questions.
Response 3
The article is not aimed at the prevailing use of terms and meanings, which is very interesting but not included in our field, but at consistency within norms, in relation to the hierarchy of norms.
Comments 4
Moreover, the author presents his own opinion as the most correct. On some questions I can agree, on others - not. When reading the article, the author's selectivity and methodology are not clear
Response 4
The author's only opinion in this article is the usefulness of consistency among the standards for the harmonization of their practical consequences. The opinions of the author and fellow contributors are expressed in the moments of drafting and discussion of the standards, not excluding the BIPM Vocabulary itself.
Comments 5
Therefore, one of the main my comments: the materials and methods section is composed incorrectly, in my opinion. Here I would like to see what methodology the author used to perform his analysis. How did he evaluate the terminology discrepancies and errors? Is the author expressing his personal opinion or did he use some well-founded and generally recognized scientific approach to the analysis?
That is why the Materials and Methods section exists. It is to explain the chosen tool. However, the presented section is essentially a continuation of the Introduction section and explains the situation, but does not provide a methodology for its analysis. It needs to be rewritten.
Response 5
The materials and methods section will be rewritten to better represent the activity performed.
Two paragraphs are moved to the introduction.
The following paragraph is added:
In reviewing and commenting on the draft documents proposed by ISO and CLSI, we noted differences with standards of higher hierarchy, such as VIM and ISO 15189. We recorded the reasons presented by ISO or CLSI for decisions on our comments.
Comments 6
It would also be correct to collect and present the problematic issues separately, and to provide a separate section "Author's opinion". Many sections now are presented as the mixed composition of the situation and the author's opinion.
Response 6
Opinions on individual terms and definitions of the author, and colleagues who relate to each other, are expressed in the moments of drafting and discussion of standards, not excluding the BIPM Vocabulary itself. In the article, opinions are collected in the “Discussion” section, while in the “Results” are collected the data that emerged from the normative work, especially in the table.
Comments 7
In the article there are also no references to the publications of other authors, to university textbooks, to dictionaries, etc., where metrological terminology is also given and discussed. It is not explained what the known position of other authors is on the controversial issues under discussion. In a serious analytical article, it is important to present different opinions.
Response 7
The highest-level source of terminology guidance is the BIPM Vocabulary. Numerous articles are known about the validity of BIPM proposals, but we find little on the specific topic covered in the article, harmonization in ISO and CLSI. On the contrary, we have recorded decisions of individual groups in ISO and CLSI in blatant violation of the principle of harmonization with BIPM and ISO 15189, without justifications based on the literature, but only on exquisitely personal views linked to “common usage.” Since these are data extracted from the draft comment process, the views of others, except those of the ISO Secretariat or CLSI Committee, are not available.
Reviewer 2 Report
Comments and Suggestions for AuthorsThe author discusses the important problem of defining precise, coherent, and clear vocabulary for all standards, guidelines, and other essential documents used in various laboratories, with a particular focus on medical laboratories. The issue is very important, and a detailed discussion provides insight into the problems of the harmonization process. The importance of the discussed problem can't be denied.
Yet, the paper suffers several issues that must be handled before being published.
1) Citation format must be unified.
2) All mentioned documents should be added to the references list (in particular the mentioned standards must be added with full reference data).
3) In order to make the reading process easier, I also encourage an author to add the citation references in Table 1. It may seem a bit unorthodox but can be very useful.
4) Some minor typo errors were noticed. Please correct them. In particular in abstract: ("easurement", "pomparability").
5) Lines 344-349 contain redundant phrases.
6) Some of the sentences present an emotionally saturated attitude. While I understand the frustration of the author (who obviously was engaged in the editing processes of some of the mentioned documents), the reception of such comments may work somehow against the paper.
Comments on the Quality of English LanguageThe language is proper. The text is easy to understand. Some minor issues should be corrected.
Author Response
The reviewer's comments are very welcome; they will be accommodated as far as possible.
Comments 0
The author discusses the important problem of defining precise, coherent, and clear vocabulary for all standards, guidelines, and other essential documents used in various laboratories, with a particular focus on medical laboratories. The issue is very important, and a detailed discussion provides insight into the problems of the harmonization process. The importance of the discussed problem can't be denied.
Response 0
Thank you.
Comments 1
Yet, the paper suffers several issues that must be handled before being published. 1) Citation format must be unified.
Response 1
All references have been reviewed, corrected and updated with https://www.mdpi.com/authors/references. Any minor errors entrusted to the Editors.
Comments 2
2) All mentioned documents should be added to the references list (in particular the mentioned standards must be added with full reference data).
Response 2
Since these are documents under discussion, not yet published, unfortunately it is not possible to provide an exact citation. Citing the earlier version, which is also readily available, would not be correct.
Comments 3
3) In order to make the reading process easier, I also encourage an author to add the citation references in Table 1. It may seem a bit unorthodox but can be very useful.
Response 3
See Comment 2
Comments 4
4) Some minor typo errors were noticed. Please correct them. In particular in abstract: ("easurement", "pomparability").
Response 4
Done. Thank you.
Comments 5
5) Lines 344-349 contain redundant phrases.
Response 5
Done, thank you.
Comments 6
6) Some of the sentences present an emotionally saturated attitude. While I understand the frustration of the author (who obviously was engaged in the editing processes of some of the mentioned documents), the reception of such comments may work somehow against the paper.
Response 6
Good point. In fact, the work with ISO and CLSI was by no means negative; many of our remarks on terminology were accepted. The article reports those that still find obstacles, in the hope that the discussion will remain heated and lead to improvements in the guidance documents. Paragraph 5 has been rewritten considering this recommendation.
Reviewer 3 Report
Comments and Suggestions for AuthorsIt is always of interest to hear opinions from the user community about the Joint Guides for Metrology (JCGM) and this paper is a good example from, as the author claims, one of the largest measurement industries, namely medical laboratories. Most of the following comments I have are editorial but a couple of interesting points are worth highlighting: (i) how best to term and treat nominal (and ordinal) properties and concepts and (ii) emphasising conformity assessment in metrological vocabularies.
Line 2 Does the author mean by "the metrology vocabulary", the JCGM VIM? If so, then the title of the essay could be modified to make this clearer.
Line 3 Add "...for medical laboratories".
Line 12 Explain the abbreviation CLSI: Clinical and Laboratory Standards Institute
Lines 13, 22, 55, 63, 66, 159, 244, 318, 446, 453, 466: "ISO" here appears to refer to ISO/TC 212. This should be made explicit since ISO is also part of the JCGM WG2 VIM work. Could the author please add a brief explanation of the relations between ISO and the Joint Committee for Guides in Metrology (JCGM) where the latter includes WG2 which is charged with drafting the VIM? ISO is one of the 7 organisations composing the JCGM and should have every opportunity of contributing to the VIM.
Line 13: add "... of the JCGM"
Line 61: This manuscript is also concerned with regulatory issues (line 37), so a discussion could be usefully added to include conformity assessment terminology (e.g. ISO 17000, where terms such as "examination", "measurand", "quality characteristic" etc could be relevant).
Line 65: "some chapters" - please specify which documents you are referring to.
First line of Table 1: "Measurand" - the quantity intended to be measured - is a metrological term (in the VIM). "Quality characteristic" (as in ISO 17000 Conformity Assesment) - the quantity intended to be assessed - is a better term if the main focus on regulation. Secondly, note that these terms refer to "quantity" which in my opinion is not synonymous with "analyte": the respective terms would better be: "concentration" and "object".
Midline of Table 1, Lines 189 & 219: The other JCGM working group - WG1 GUM - produces guides to the expression of measurement uncertainty. The GUM is a good forum for considering these error-related terms.
Line 77: Exactly - the same comment I have at line 72: 'Measurand' - the quantity intended to be measured - is a metrological term (in the VIM). 'Quality characteristic' (as in ISO 17000 Conformity Assesment) - the quantity intended to be assessed - is a better term if the main focus on regulation. Note that these terms refer to "quantity" which in my opinion is not synonymous with "analyte": the respective terms would better be: "concentration" and "object".
Line 83: item 2.6 of the VIM can be criticised on (at least) two points:
(i) "examination" implies inspection (see ISO/IEC definition below) which is an action in the context of conformity assessment, while metrology (à la VIM) deals with quality-assured measurement which is only a subset of CA. (Historically it was a medical doctor (the late R Dybkaer) who introduced this terminology, but he was thinking mainly of clinical examinations. Nominal properties do not exclusively belong to a test situation nor are they necessarily extensive.)
The ISO/IEC 17000 definition §4.3 inspection
examination of a product design, product (3.3), process or installation and determination of its conformity with specific requirements or, on the basis of professional judgement, with general requirements
NOTE Inspection of a process may include inspection of persons, facilities, technology and methodology.
(ii) IUPAC (and thereafter the VIM) chose to refer only to nominal properties, but many aspects of ordinal properties can be dealt with at the same time.
As at line 83, I would not recommend using 'examining' when referring to 'nominal' properties: an examination - which either involves a test or is extensive - is only a particular kind of classification of nominal properties; there are many other nominal classifications which are neither tests nor extensive. By the way, 'examining' (or more correctly ' classification') is the act of observation of an attribute (e.g. quality characteristic - the property intended to be assessed, in conformity assessment) rather than analogous to the 'measurand', the quantity intended to be measured [Pendrill 2019].
L R Pendrill 2019, Quality Assured Measurement – Unification across Social and Physical Sciences , Springer Series in Measurement Science and Technology, ISBN: 978-3-030-28695-8 (e-book), https://doi.org/10.1007/978-3-030-28695-8
Line 95: As at the 1st line of Table 1, I would also object to replacing 'analyte' by 'measurand' on purely metrological grounds: Note that 'measurand' refer to "quantity" which in my opinion is not synonymous with "analyte": the respective metrological terms would better be: "concentration" and "object".
Line 114 Please explain the choice of term "lemma" in this context.
Line 126 Current procedures in the EU - such as the MID and MDR - have different modules of conformity. Which organisation can make the "examination" varies: in some modules examination is done by a laboratory while in other modules a manufacturer can do the examination. Note (as at line 83) that "examination" and "measurement" are not synonyms (even for nominal properties).
Line 132 Recent advances (e.g. Pendrill 2019) have proposed a metrological (logistic regression) approach to nominal and ordinal properties (not covered by the text in lines 135 ff). That approach has recently led to significant improvements in clinical studies of correlations between cognition and biomarkers for Alzheimer's disease [Göschel et al. 2024)].
I have already mentioned at line 83, IUPAC (and EURACHEM and the VIM) chose to refer only to nominal properties, but many aspects of ordinal properties can be dealt with at the same time.
Chemists such as Ellison have given the impression that this field is "complex", "confusing" and "difficult". I am however confident that solutions exist and that, in fact, once understood, things often become simple and easy in hindsight.
Göschel et al. 2024, “Plasma p-Tau 181 and GFAP reflect 7T MR-derived changes in Alzheimer’s disease: a longitudinal study of structural and functional MRI and MRS”, Alzheimer's & Dementia, DOI: 10.1002/alz.14318
Line 137. Stating that "semi-quantitative examples are often quantitative expressed semi-quantitatively" is difficult to challenge and not particularly informative.
Line 160. I repeat my comments at line 133.
Line 206 Replace the word "practises" by: '...adopts the term "measurement error" in several guides...'
Line 208. Note that all terms mentioned in the 1st paragraph of this section 3.2 coming from VIM3 are metrological terms. But there is one exception, namely "maximum permissible error", which belongs to the conformity assessment of measurement. (VIM WG2 has repeatedly declared that conformity assessment is out of scope for their part.) Please add some words of explanation in the text here.
Line 223 As at Line 208. I would use the term 'conformity' rather than 'operational'. In any case, metrology is often justified as an activity in support of conformity assessment, rather than as purely academic. VIM WG2 has unfortunately repeatedly declared that conformity assessment is out of scope for their part.
Line 227 See my comment at line 223
Line 228. As at line 208, it is important to make it clear which terms belong to the conformity assessment of measurement, as opposed to purely metrological terms. (VIM WG2 has repeatedly declared that conformity assessment is out of scope for their part.) Please add some words of explanation to the text here.
Line 230 Check this sentence: some words seem to be missing...
Line 257 As mentioned, the VIM has chosen not to include conformity assessment terminology (unfortunately). Many of the performance terms in this paragraph can be associated with attributes of the various elements of a measurement system (object, instrument, operator, environment and method). Analysis of such measurement systems - e.g. in proficiency testing and other interlaboratory experiments - are essential parts of measurement conformity which in turn supports general product conformity assessment [Pendrill 2019].
Line 283 As at line 257.
Line 290 See my comments at Line 133. All of the regular metrological performance terms can be also applied to ordinal and nominal properties provided a logistic regression transformation is made first.
Line 397 Note that recent work on the metrology of categorical observations (line 133) has shown how reference procedures (as opposed to material) can in fact be defined, provided one first applies a logistic regression transformation to the raw data.
Author Response
The Reviewer's comments are very accurate and thorough. Many thanks for the material corrections to be made to the text. On the conceptual issues, due reflection will be made.
Comments 1
It is always of interest to hear opinions from the user community about the Joint Guides for Metrology (JCGM) and this paper is a good example from, as the author claims, one of the largest measurement industries, namely medical laboratories. Most of the following comments I have are editorial but a couple of interesting points are worth highlighting: (i) how best to term and treat nominal (and ordinal) properties and concepts and (ii) emphasising conformity assessment in metrological vocabularies.
Response
Thank you. I respond below to the comments point by point.
Comments 2
Line 2 Does the author mean by "the metrology vocabulary", the JCGM VIM? If so, then the title of the essay could be modified to make this clearer.
Response 2
The title is completed by proposing the citation.
Comments 3
Line 3 Add "...for medical laboratories".
Response 3
The title is completed by proposing the specification.
Comments 4
Line 12 Explain the abbreviation CLSI: Clinical and Laboratory Standards Institute
Response 4
The text has been completed.
Comments 5
Lines 13, 22, 55, 63, 66, 159, 244, 318, 446, 453, 466: "ISO" here appears to refer to ISO/TC 212. This should be made explicit since ISO is also part of the JCGM WG2 VIM work. Could the author please add a brief explanation of the relations between ISO and the Joint Committee for Guides in Metrology (JCGM) where the latter includes WG2 which is charged with drafting the VIM? ISO is one of the 7 organisations composing the JCGM and should have every opportunity of contributing to the VIM.
Response 5
ISO participates in the work of JCGM WG2 VIM. However, individual ISO document drafting and review groups act completely independently, often leaking incomplete knowledge of metrology documents and even other ISO documents themselves, such as ISO 15189 or ISO 18113.
The text has been completed with “ISO/TC 212“ where needed.
Comments 6
Line 13: add "... of the JCGM"
Response 6
Done
Comments 7
Line 61: This manuscript is also concerned with regulatory issues (line 37), so a discussion could be usefully added to include conformity assessment terminology (e.g. ISO 17000, where terms such as "examination", "measurand", "quality characteristic" etc could be relevant).
Response 7
ISO 17000 is certainly an interesting and essential source for the whole chain of documents on compliance verification. However, it does not appear to be currently under review, and our organizations (SIPMeL and WASPaLM) do not participate directly in the work of ISO/CASCO, so ISO 17000 remains outside the scope of the article.
Comments 8
Line 65: "some chapters" - please specify which documents you are referring to.
Response 8
Text modified.
Comments 9
First line of Table 1: "Measurand" - the quantity intended to be measured - is a metrological term (in the VIM). "Quality characteristic" (as in ISO 17000 Conformity Assesment) - the quantity intended to be assessed - is a better term if the main focus on regulation. Secondly, note that these terms refer to "quantity" which in my opinion is not synonymous with "analyte": the respective terms would better be: "concentration" and "object".
Response 9
Certainly “quantity” is not at all synonymous with “analyte,” we try to make the point. The observation is not quite clear. In the terms of ISO 17000 we do not find “ Quality characteristic,” which is seen instead in ISO 9000:2015. In any case, discussion of this topic (while useful) would perhaps be best opened in the context of standards revision, rather than in the article that seeks to limit itself to remarks about harmonization of terms.
Comments 10
Midline of Table 1, Lines 189 & 219: The other JCGM working group - WG1 GUM - produces guides to the expression of measurement uncertainty. The GUM is a good forum for considering these error-related terms
Response 10
Appreciable remark. A reference to GUM is added (in 4.Discussion).
JCGM 100:2008(E) Evaluation of measurement data - Guide to the expression of uncertainty in measurement (2008). Bureau International des Poids et Mesures (BIPM): Sèvres Cedex FR, 2008.
DOI: https://doi.org/10.59161/JCGM100-2008E
Comments 11
Line 77: Exactly - the same comment I have at line 72: 'Measurand' - the quantity intended to be measured - is a metrological term (in the VIM). 'Quality characteristic' (as in ISO 17000 Conformity Assesment) - the quantity intended to be assessed - is a better term if the main focus on regulation. Note that these terms refer to "quantity" which in my opinion is not synonymous with "analyte": the respective terms would better be: "concentration" and "object".
Response 11
Certainly “quantity” is by no means synonymous with “analyte,” we try to highlight that. However, in the terms of ISO 17000 we do not find “Quality characteristic,” which is seen instead in ISO 9000:2015. Discussion on the topic would be useful, but it should be opened in the context of standards revision, rather than in the article, which merely remarks on harmonization of terms.
Comments 12
Line 83: item 2.6 of the VIM can be criticised on (at least) two points: (i) "examination" implies inspection (see ISO/IEC definition below) which is an action in the context of conformity assessment, while metrology (à la VIM) deals with qualityassured measurement which is only a subset of CA. (Historically it was a medical doctor (the late R Dybkaer) who introduced this terminology, but he was thinking mainly of clinical examinations. Nominal properties do not exclusively belong to a test situation nor are they necessarily extensive.)
The ISO/IEC 17000 definition §4.3 inspection examination of a product design, product (3.3), process or installation and determination of its conformity with specific requirements or, on the basis of professional judgement, with general requirements
NOTE Inspection of a process may include inspection of persons, facilities, technology and methodology.
Response 12
The reference to ISO/IEC 17000:2020 “6.3 inspection” is interesting; it could be used in discussions on document writing. So far, it does not seem that VIM and IUPAC consider it, apart from VIM4 5.24 [VIM3: 2.44] verification and VIM4 5.25 [VIM3: 2.45] validation, very briefly. The article is limited to comparisons with VIM and IFCC-IUPAC; it does not reach the comparison with ISO/IEC 17000:2020.
Comments 13
(ii) IUPAC (and thereafter the VIM) chose to refer only to nominal properties, but many aspects of ordinal properties can be dealt with at the same time.
Response 13
I very much agree that the management of ordinal results would deserve a more comprehensive treatment. We have already proposed this to the BIPM group, but it is beyond the scope of the article.
Comments 14
As at line 83, I would not recommend using 'examining' when referring to 'nominal' properties: an examination - which either involves a test or is extensive - is only a particular kind of classification of nominal properties; there are many other nominal classifications which are neither tests nor extensive. By the way, 'examining' (or more correctly ' classification') is the act of observation of an attribute (e.g. quality characteristic - the property intended to be assessed, in conformity assessment) rather than analogous to the 'measurand', the quantity intended to be measured [Pendrill 2019].
L R Pendrill 2019, Quality Assured Measurement – Unification across Social and Physical Sciences , Springer Series in Measurement Science and Technology, ISBN: 978-3- 030-28695-8 (e-book), https://doi.org/10.1007/978-3-030-28695- 8
Response 14
Interesting observation, useful in discussing the revisions of the BIPM and IFCC-IUPAC documents. The article is limited to finding the points of inconsistency between documents. For now, we do not intend to discuss the choice of ISO and IUPAC for the term “review.” Thank you for the reference to Pendrill's book.
Comments 15
Line 95: As at the 1st line of Table 1, I would also object to replacing 'analyte' by 'measurand' on purely metrological grounds: Note that 'measurand' refer to "quantity" which in my opinion is not synonymous with "analyte": the respective metrological terms would better be: "concentration" and "object".
Response 15
Certainly “quantity” is by no means synonymous with “analyte,” we try to highlight that. However, in the terms of ISO 17000 we do not find “Quality characteristic,” which is seen instead in ISO 9000:2015. Discussion on the topic would be useful, but it should be opened in the context of standards revision, rather than in the article, which merely remarks on harmonization of terms.
Comments 16
Line 114 Please explain the choice of term "lemma" in this context.
Response 16
“measuring range” is a lemma, as is ”measuring interval.” VIM3 does not contain “analytical measuring interval,” used and abbreviated by CLSI as “AMI.”
Comments 17
Line 126 Current procedures in the EU - such as the MID and MDR - have different modules of conformity. Which organisation can make the "examination" varies: in some modules examination is done by a laboratory while in other modules a manufacturer can do the examination. Note (as at line 83) that "examination" and "measurement" are not synonyms (even for nominal properties).
Response 17
“Examination” as a service for medical diagnosis is defined by ISO 15189 and performed by laboratories, not manufacturers. Manufacturers provide examination materials, not examinations, according to ISO 15189. Our version has been accepted. IUPAC is moving toward the use of “measurement” for nominal properties as well (Possolo A, Hibbert D, Stohner J, Bodnar O, Meija J. A brief guide to measurement uncertainty (IUPAC Technical Report). Pure and Applied Chemistry. 2024;96(1): 113-134. https://doi.org/10.1515/pac-2022-1203)
Comments 18
Line 132 Recent advances (e.g. Pendrill 2019) have proposed a metrological (logistic regression) approach to nominal and ordinal properties (not covered by the text in lines 135 ff). That approach has recently led to significant improvements in clinical studies of correlations between cognition and biomarkers for Alzheimer's disease [Göschel et al. 2024)] .
I have already mentioned at line 83, IUPAC (and EURACHEM and the VIM) chose to refer only to nominal properties, but many aspects of ordinal properties can be dealt with at the same time. Chemists such as Ellison have given the impression that this field is "complex", "confusing" and "difficult". I am however confident that solutions exist and that, in fact, once understood, things often become simple and easy in hindsight.
Göschel et al. 2024, “Plasma p-Tau 181 and GFAP reflect 7T MR-derived changes in Alzheimer’s disease: a longitudinal study of structural and functional MRI and MRS”, Alzheimer's & Dementia, DOI: 10.1002/alz.14318
Response 18
Thank you for the reports of the literature. The ordinal results certainly deserve a better treatment than those so far available and used in the article. We will treasure them and present them at the earliest opportunity in ISO and CLSI.
Comments 19
Line 137. Stating that "semi-quantitative examples are often quantitative expressed semi-quantitatively" is difficult to challenge and not particularly informative.
Response 19
I agree with the Reviewer. Unfortunately, the definition of ISO 18113 is exactly that, perhaps too hasty in order to get rid of the thorny issue.
Comments 20
Line 160. I repeat my comments at line 133.
Response 20
Thank you for the reports of the literature. The ordinal results certainly deserve a better treatment than those so far available and used in the article. We will treasure them and present them at the earliest opportunity in ISO and CLSI.
Comments 21
Line 206 Replace the word "practises" by: '...adopts the term "measurement error" in several guides...'
Response 21
Done. Thank you.
Comments 22
Line 208. Note that all terms mentioned in the 1st paragraph of this section 3.2 coming from VIM3 are metrological terms. But there is one exception, namely "maximum permissible error", which belongs to the conformity assessment of measurement. (VIM WG2 has repeatedly declared that conformity assessment is out of scope for their part.) Please add some words of explanation in the text here.
Response 22
VIM4 3.28 [VIM3: 4.26; VIM2: 5.21; VIM1: 5.23] maximum permissible measurement error, maximum permissible error, limit of error, MPE: extreme measurement error, with respect to a known reference value, permitted by specifications or regulations for a given measurement, measuring instrument, or measuring system working at the rated operating conditions
Comments 23
Line 223 As at Line 208. I would use the term 'conformity' rather than 'operational'. In any case, metrology is often justified as an activity in support of conformity assessment, rather than as purely academic. VIM WG2 has unfortunately repeatedly declared that conformity assessment is out of scope for their part.
Response 23
From a practical point of view, we cannot distinguish metrology from compliance verification in laboratories, despite WG2's statements, which we do not find in VIM, however. The article is devoted to findings on term matches, not to the study of their correctness, appropriateness or other characteristics.
Comments 24
Line 227 See my comment at line 223
Response 24
Unfortunately, VIM defines several terms also used for compliance verification. According to the proposed article, it would be preferable for them to be consistent.
Comments 25
Line 228. As at line 208, it is important to make it clear which terms belong to the conformity assessment of measurement, as opposed to purely metrological terms. (VIM WG2 has repeatedly declared that conformity assessment is out of scope for their part.) Please add some words of explanation to the text here.
Response 25
We do not find the scope statement in VIM3 or VIM4. In contrast, conformity is found in VIM4 5.24 [VIM3: 2.44] verification , VIM4 6.15 [new] reliability review, and in citations 17. ISO/IEC 17000, Conformity assessment - Vocabulary and general principles, 19. ISO/IEC 17029, Conformity assessment - General principles and requirements for validation and verification bodies, 33. JCGM 106, Evaluation of measurement data - The role of measurement uncertainty in conformity assessment.
Comments 26
Line 230 Check this sentence: some words seem to be missing...
Response 26
Sentence rewritten for clarity.
The tendency in CLSI to propose method comparison procedures with a fairly high frequency is evident.
Comments 27
Line 257 As mentioned, the VIM has chosen not to include conformity assessment terminology (unfortunately). Many of the performance terms in this paragraph can be associated with attributes of the various elements of a measurement system (object, instrument, operator, environment and method). Analysis of such measurement systems - e.g. in proficiency testing and other interlaboratory experiments - are essential parts of measurement conformity which in turn supports general product conformity assessment [Pendrill 2019].
Response 27
We do not find this statement in VIM3 or VIM4, although something similar is found in Pendrill 2019 (page 95). However, from a practical point of view, we struggle in laboratories to distinguish metrology from compliance verification, despite WG2's claims. The article is devoted to findings on term matches, not to the study of their correctness, appropriateness or other characteristics. Our activity (as laboratories and as assessors) is exercised by combining metrology requirements with compliance requirements together, as argued in doctrinal terms even by Pendrill.
Comments 28
Line 283 As at line 257.
Response 28
Our activity (as laboratories and as assessors) is exercised by combining metrology requirements with compliance requirements together, as argued in doctrinal terms even by Pendrill.
Comments 29
Line 290 See my comments at Line 133. All of the regular metrological performance terms can be also applied to ordinal and nominal properties provided a logistic regression transformation is made first.
Response 29
Thank you for the reports of the literature. The ordinal results certainly deserve a better treatment than those so far available and used in the article. We will treasure them and present them at the earliest opportunity in ISO and CLSI.
Comments 30
Line 397 Note that recent work on the metrology of categorical observations (line 133) has shown how reference procedures (as opposed to material) can in fact be defined, provided one first applies a logistic regression transformation to the raw data.
Response 30
Commutativity testing is a very demanding task, which can be very expensive for laboratories. The choice of words must be very prudent, so as not to induce waste of resources (buying materials, spending a lot of time in testing) and risk of errors. The discussion on methodologies, which is very interesting, is beyond the scope of this article. It will certainly be taken up by us in the future.
Round 2
Reviewer 1 Report
Comments and Suggestions for AuthorsThe authors have made general corrections to the main part of my comments. The article can be published in this version.
Reviewer 3 Report
Comments and Suggestions for AuthorsThank you, authors, for your consideration of my comments.
