Neurofilament ELISA validation
Open accessAbstract
Background Neurofilament proteins (Nf) are highly specific biomarkers for neuronal death and axonal degeneration. As these markers become more widely used, an inter-laboratory validation study is required to identify assay criteria for high quality performance.Methods The UmanDiagnostics NF-light (R)enzyme-linked immunoabsorbent assays (ELISA) for the neurofilament light chain (NfL, 68kDa) was used to test the intra-assay and inter-laboratory coefficient of variation (CV) between 35 laboratories worldwide on 15 cerebrospinal fluid (CSF) samples. Critical factors, such as sample transport and storage, analytical delays, reaction temperature and time, the laboratories' accuracy and preparation of standards were documented and used for the statistical analyses.Results The intra-laboratory CV averaged 3.3% and the inter-laboratory CV 59%. The results from the test laboratories correlated with those from the reference laboratory (R=0.60, p<0.0001). Correcting for critical factors improved the strength of the correlation. Differences in the accuracy of standard preparation were identified as the most critical factor. Correcting for the error introduced by variation in the protein standards improved the correlation to R=0.98, p<0.0001 with an averaged inter-laboratory CV of 14%. The corrected overall inter-rater agreement was subtantial (0.6) according to Fleiss' multi-rater kappa and Gwet's AC1 statistics.Conclusion This multi-center validation study identified the lack of preparation of accurate and consistent protein standards as the main reason for a poor inter-laboratory CV. This issue is also relevant to other protein biomarkers based on this type of assay and will need to be solved in order to achieve an acceptable level of analytical accuracy. The raw data of this study is available online.
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During a PubMed search up to February 2013, only 2 published articles were found that mention using Gwet's AC1 method as part of a study [28,29].
“During our research of PubMed (up to February 2013), we found only 2 published articles that mention using Gwet’s AC1 method as part of a study [28,29].”
From A comparison of cohen's Kappa and gwet's AC1 when calculating inter-rater reliability coefficients: A study conducted with personality disorder samples (2013) · cites this paper as [28]
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References 20 · Cited by 105
Research works printed but not linked: 2
- NA Verwey, WM van der Flier, K Blennow, C Clark, S Sokolow, PP De Deyn, D Galasko, H Hampel, T Hartmann, E Kapaki, L Lannfelt, PD Mehta, L Parnetti, A Petzold, T Pirttila, L Saleh, A Skinningsrud, JC v. Swieten, MM Verbeek, J Wiltfang, S Younkin, P Scheltens, and MA Blankenstein. A worldwide multicenter comparison of assays for CSF biomarkers in Alzheimer disease. Ann Clin Biochem. (in press).
- G Shaw. Neurofilaments. Springer-Verlag, 1998.
- Authors
- Petzold, A., Altintas, A., Andreoni, L., Bartos, A., Berthele, A., Blankenstein, M. A., Buee, L., Castellazzi, M., Cepok, S., Comabella, M., Constantinescu, C. S., Deisenhammer, F., Deniz, G., Erten, G., Espiño, M., Fainardi, E., Franciotta, D., Freedman, M. S., Giedraitis, V., Gilhus, N. E., Giovannoni, G., Glabinski, A., Grieb, P., Hartung, H.-P., Hemmer, B., Herukka, S.-K., Hintzen, R., Ingelsson, M., Jackson, S., Jacobsen, S., Jafari, N., Jalosinski, M., Jarius, S., Kapaki, E., Kieseier, B. C., Koel-Simmelink, M. J. A., Kornhuber, J., Kuhle, J., Kurzepa, J., Lalive, P. H., Lannfelt, L., Lehmensiek, V., Lewczuk, P., Livrea, P., Marnetto, F., Martino, D., Menge, T., Norgren, N., Papuć, E., Paraskevas, G. P., Pirttilä, T., Rajda, C., Rejdak, K., Ricny, J., Ripova, D., Rosengren, L., Ruggieri, M., Schraen, S., Shaw, G., Sindic, C., Siva, A., Stigbrand, T., Stonebridge, I., Topcular, B., Trojano, M., Tumani, H., Twaalfhoven, H. A. M., Vécsei, L., Van Pesch, V., Vanderstichele, H., Vedeler, C., Verbeek, M. M., Villar, L. M., Weissert, R., Wildemann, B., Yang, C., Yao, K., & Teunissen, C. E.
- Affiliations
- National Hospital for Neurology and Neurosurgery (GB)
- Fondazione Istituto Neurologico Nazionale Casimiro Mondino (IT)
- TUM Klinikum (DE)
- Vrije Universiteit Amsterdam (NL)
- University of Ferrara (IT)
- Universitat Autònoma de Barcelona (ES)
- University of Nottingham (GB)
- Innsbruck Medical University (AT)
- Istanbul University (TR)
- Hospital Universitario Ramón y Cajal (ES)
- Arcispedale Sant'Anna (IT)
- Ottawa Hospital (CA)
- Uppsala University (SE)
- Haukeland University Hospital (NO)
- Queen Mary University of London (GB)
- Heinrich Heine University Düsseldorf (DE)
- Technical University of Munich (DE)
- University of Eastern Finland (FI)
- Erasmus University Rotterdam (NL)
- Heidelberg University (DE)
- National and Kapodistrian University of Athens (GR)
- Medical University of Lublin (PL)
- University of Geneva (CH)
- Universität Ulm (DE)
- University of Bari Aldo Moro (IT)
- University of Szeged (HU)
- University of Gothenburg (SE)
- University of Florida (US)
- Umeå University (SE)
- Fujirebio (Belgium) (BE)
- University of Bergen (NO)
- Radboud University Nijmegen (NL)
- Corresponding author
- Petzold, Axel
- ORCID
- Petzold, Axel
- Berthele, Achim
- Blankenstein, Marinus A.
- Castellazzi, Massimiliano
- Comabella, Manuel
- Constantinescu, Cris S.
- Deisenhammer, Florian
- Erten, Gaye
- Espiño, Mercedes
- Fainardi, Enrico
- Franciotta, Diego
- Freedman, Mark S.
- Giedraitis, Vilmantas
- Gilhus, Nils Erik
- Giovannoni, Gavin
- Glabinski, Andrzej
- Hemmer, Bernhard
- Herukka, Sanna-Kaisa
- Hintzen, Rogier
- Ingelsson, Martin
- Jafari, Naghmeh
- Jarius, Sven
- Kornhuber, Johannes
- Kurzepa, Jacek
- Lalive, Patrice H.
- Lannfelt, Lars
- Lewczuk, Piotr
- Livrea, Paolo
- Martino, Davide
- Menge, Til
- Paraskevas, George P.
- Rajda, Cecília
- Rejdak, Konrad
- Rosengren, Lars
- Ruggieri, Maddalena
- Shaw, Gerry
- Tumani, Hayrettin
- Vécsei, László
- Vedeler, Christian
- Verbeek, Marcel M.
- Weissert, Robert
- Wildemann, Brigitte
- Yang, Cui
- Teunissen, Charlotte E.
- Venue
- Journal of Immunological Methods
- Publisher
- Elsevier BV
- Published
- 2010-01
- Volume
- 352
- Issue
- 1-2
- Pages
- 23-31
- ISSN
- 0022-1759 (ISSN-L)
- OpenAlex
- W2099058096
- Cited by
- 105
- References
- 20
- Citations by year
- 2026: 1 · 2025: 7 · 2024: 4 · 2023: 5 · 2022: 8 · 2021: 7 · 2020: 9 · 2019: 10 · 2018: 10 · 2017: 5 · 2016: 6 · 2015: 9 · 2014: 5 · 2013: 4 · 2012: 5
- FWCI
- 3.09
- Type
- journal article
- Language
- en
- Open access
- green
- discovery.ucl.ac.uk
- Licence
- Locations
- Journal of Immunological Methods (publishedVersion)
- PubMed (publishedVersion)
- Pure Amsterdam UMC (publishedVersion)
- Amsterdam UMC (VU Amsterdam) - Institutional Repository (publishedVersion)
- SZTE Publicatio Repozitórium (University of Szeged) (acceptedVersion)
- UCL Discovery (University College London) (submittedVersion)
- Digital Academic REpository of VU University Amsterdam (Vrije Universiteit Amsterdam) (submittedVersion)
- Digital Access to Libraries (Université catholique de Louvain (UCL), l'Université de Namur (UNamur) and the Université Saint-Louis (USL-B)) (submittedVersion)
- Florence Research (University of Florence) (submittedVersion)
- mediaTUM – the media and publications repository of the Technical University Munich (Technical University Munich) (submittedVersion)
- Radboud Repository (Radboud University) (submittedVersion)
- CINECA IRIS Institutional Research Information System (University of Bari Aldo Moro) (submittedVersion)
- Institutional Research Information System University of Ferrara (University of Ferrara) (submittedVersion)
- Data Archiving and Networked Services (DANS) (submittedVersion)
- Topics
- Health Sciences › Medicine › Physiology › Clinical Laboratory Practices and Quality Control
- Social Sciences › Decision Sciences › Statistics, Probability and Uncertainty › Reliability and Agreement in Measurement
- Life Sciences › Biochemistry, Genetics and Molecular Biology › Molecular Biology › Advanced Biosensing Techniques and Applications
- Keywords
- neurofilament light chain, neurofilament biomarkers, cerebrospinal fluid, interlaboratory validation, coefficient of variation, analytical accuracy, interobserver agreement, neuronal cell death, axonal degeneration
- MeSH terms
- Enzyme-Linked Immunosorbent Assay, Humans, Neurons, Reference Standards, Specimen Handling, Temperature, Time Factors, Reproducibility of Results, Biomarkers, Observer Variation, Neurofilament Proteins, Cell Death
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