From metabolic profiles to clinical interpretation: multivariate approaches to population-based and personalized reference intervals and reference change values
Abstract
Interpretation of laboratory test results is a comparative process that requires reference data. Such data are derived for each analyte separately, without accounting for, the interrelationships among analytes. Physicians use test panels containing multiple analytes to enhance clinical significance and improve the accuracy of decision-making. However, current interpretation practices apply reference intervals and reference change values in a univariate manner – that is, each analyte in the panel is interpreted independently and no reference data are available to interpret the panel as a whole. Yet, metabolism is a network of biomolecules, each of which is related to others. Therefore, a multivariate approach – based on the correlations among biomolecules – can provide a more informative reference than univariate approaches and can be used more effectively in the interpretation of laboratory data. This concept can be summarized by a motto: Combine single tests into meaningful groups, but interpret the group as a single clinical entity. In this opinion paper, we present a practical approach for obtaining reference data for both reference intervals and reference change values to interpret laboratory test panels composed of related analytes.
Acknowledgments
The authors utilized ChatGPT (GPT-4, OpenAI) to improve the language and clarity of the manuscript and to assist with the explanation of certain concepts including the Python code provided in the Supplemental File. All scientific content, analyses, and interpretations were conceived, conducted, and written by the authors.
-
Research ethics: Not applicable.
-
Informed consent: Not applicable.
-
Author contributions: The authors have accepted responsibility for the entire content of this manuscript and approved its submission.
-
Use of Large Language Models, AI and Machine Learning Tools: The authors utilized ChatGPT (GPT-4, OpenAI) to improve the language and clarity of the manuscript.
-
Conflict of interest: The authors state no conflict of interest.
-
Research funding: None declared.
-
Data availability: None declared.
References
1. Coskun, A, Sandberg, S, Unsal, I, Serteser, M, Aarsand, AK. Personalized reference intervals: from theory to practice. Crit Rev Clin Lab Sci 2022;59:501–16. https://doi.org/10.1080/10408363.2022.2070905.Search in Google Scholar PubMed
2. Siest, G, Henny, J, Gräsbeck, R, Wilding, P, Petitclerc, C, Queraltó, JM, et al.. The theory of reference values: an unfinished symphony. Clin Chem Lab Med 2013;51:47–64. https://doi.org/10.1515/cclm-2012-0682.Search in Google Scholar PubMed
3. Coskun, A. Diagnosis based on population data versus personalized data: the evolving paradigm in laboratory medicine. Diagnostics 2024;14:2135. https://doi.org/10.3390/diagnostics14192135.Search in Google Scholar PubMed PubMed Central
4. Coskun, A, Lippi, G. Personalized laboratory medicine in the digital health era: recent developments and future challenges. Clin Chem Lab Med 2024;62:402–9. https://doi.org/10.1515/cclm-2023-0808.Search in Google Scholar PubMed
5. Horowitz, GL, Altaie, S, Boyd, JC, Ceriotti, F, Garg, U, Horn, P, et al.. EP28-A3c: defining, establishing, and verifying reference intervals in the clinical laboratory; approved guideline—third edition. Clin Lab Stand Inst 2010;28:12. Available from: https://clsi.org/shop/standards/ep28/.Search in Google Scholar
6. Coskun, A. Prediction interval: a powerful statistical tool for monitoring patients and analytical systems. Biochem Med (Zagreb) 2024;34:020101. https://doi.org/10.11613/bm.2024.020101.Search in Google Scholar PubMed PubMed Central
7. Coşkun, A, Sandberg, S, Unsal, I, Cavusoglu, C, Serteser, M, Kilercik, M, et al.. Personalized reference intervals in laboratory medicine: a new model based on within-subject biological variation. Clin Chem 2021;67:374–84. https://doi.org/10.1093/clinchem/hvaa233.Search in Google Scholar PubMed
8. Coskun, A, Sandberg, S, Unsal, I, Yavuz, FG, Cavusoglu, C, Serteser, M, et al.. Personalized reference intervals – statistical approaches and considerations. Clin Chem Lab Med 2021;60:629–35. https://doi.org/10.1515/cclm-2021-1066.Search in Google Scholar PubMed
9. Barabási, AL, Oltvai, ZN. Network biology: understanding the cell’s functional organization. Nat Rev Genet 2004;5:101–13. https://doi.org/10.1038/nrg1272.Search in Google Scholar PubMed
10. Jeong, H, Tombor, B, Albert, R, Oltvai, ZN, Barabási, AL. The large-scale organization of metabolic networks. Nature 2000;407:651–4. https://doi.org/10.1038/35036627.Search in Google Scholar PubMed
11. Zhu, Q, Qin, T, Jiang, YY, Ji, C, Kong, DX, Ma, BG, et al.. Chemical basis of metabolic network organization. PLoS Comput Biol 2011;7:e1002214. https://doi.org/10.1371/journal.pcbi.1002214.Search in Google Scholar PubMed PubMed Central
12. Fraser, CG. Reference change values. Clin Chem Lab Med 2012;50:807–12. https://doi.org/10.1515/cclm.2011.733.Search in Google Scholar PubMed
13. Hochberg, Y, Tamhane, AC. Multiple comparison procedures. New York, USA: John Wiley and Sons, Inc. 605 Third Ave.Search in Google Scholar
14. Chuah, TY, Lim, CY, Tan, RZ, Pratumvinit, B, Loh, TP, Vasikaran, S, et al.. Functional reference limits: describing physiological relationships and determination of physiological limits for enhanced interpretation of laboratory results. Ann Lab Med 2023;43:408–17. https://doi.org/10.3343/alm.2023.43.5.408.Search in Google Scholar PubMed PubMed Central
15. Stiksma, J, Grootendorst, DC, Van Der Linden, PWG. CA 19-9 as a marker in addition to CEA to monitor colorectal cancer. Clin Colorectal Cancer 2014;13:239–44. https://doi.org/10.1016/j.clcc.2014.09.004.Search in Google Scholar PubMed
16. van Manen, L, Groen, JV, Putter, H, Vahrmeijer, AL, Swijnenburg, RJ, Bonsing, BA, et al.. Elevated CEA and CA19-9 serum levels independently predict advanced pancreatic cancer at diagnosis. Biomarkers 2020;25:186–93. https://doi.org/10.1080/1354750x.2020.1725786.Search in Google Scholar PubMed
17. Shibutani, M, Maeda, K, Nagahara, H, Ohtani, H, Sakurai, K, Toyokawa, T, et al.. Significance of CEA and CA19-9 combination as a prognostic indicator and for recurrence monitoring in patients with stage II colorectal cancer. Anticancer Res 2014;34:3753–8.Search in Google Scholar
18. Barlési, F, Gimenez, C, Torre, JP, Doddoli, C, Mancini, J, Greillier, L, et al.. Prognostic value of combination of cyfra 21-1, CEA and NSE in patients with advanced non-small cell lung cancer. Respir Med 2004;98:357–62. https://doi.org/10.1016/j.rmed.2003.11.003.Search in Google Scholar PubMed
19. Okamura, K, Takayama, K, Izumi, M, Harada, T, Furuyama, K, Nakanishi, Y. Diagnostic value of CEA and CYFRA 21-1 tumor markers in primary lung cancer. Lung Cancer 2013;80:45–9. https://doi.org/10.1016/j.lungcan.2013.01.002.Search in Google Scholar PubMed
20. Hachem, S, Yehya, A, El Masri, J, Mavingire, N, Johnson, JR, Dwead, AM, et al.. Contemporary update on clinical and experimental prostate cancer biomarkers: a multi-omics-focused approach to detection and risk stratification. Biology (Basel). 2024;13:762. https://doi.org/10.3390/biology13100762.Search in Google Scholar PubMed PubMed Central
21. Xu, H, Lien, T, Bergholtz, H, Fleischer, T, Djerroudi, L, Vincent-Salomon, A, et al.. Multi-omics marker analysis enables early prediction of breast tumor progression. Front Genet 2021;12:670749. https://doi.org/10.3389/fgene.2021.670749.Search in Google Scholar PubMed PubMed Central
22. García-Bilbao, A, Armañanzas, R, Ispizua, Z, Calvo, B, Alonso-Varona, A, Inza, I, et al.. Identification of a biomarker panel for colorectal cancer diagnosis. BMC Cancer 2012;26:12–43.10.1186/1471-2407-12-43Search in Google Scholar PubMed PubMed Central
23. Sikaroodi, M, Galachiantz, Y, Baranova, A. Tumor markers: the potential of “omics” approach. Curr Mol Med 2010;10:249–57. https://doi.org/10.2174/156652410790963277.Search in Google Scholar PubMed
24. Mergen, EK, Karahan, S. Comparison of univariate and multivariate reference interval methods. J Clin Lab Anal 2025:e70070. https://doi.org/10.1002/jcla.70070.Search in Google Scholar PubMed PubMed Central
25. Grams, RR, Johnson, EA, Benson, ES. Laboratory data analysis system. 3. Multivariate normality. Am J Clin Pathol 1972;58:188–200. https://doi.org/10.1093/ajcp/58.2.188.Search in Google Scholar PubMed
26. Winkel, P, Lyngbye, J. The normal region-a multivariate problem. Scand J Clin Lab Invest 1972;30:339–44. https://doi.org/10.3109/00365517209084299.Search in Google Scholar PubMed
27. Winkel, P. Patterns and clusters. Multivariate approach for interpreting clinical chemistry results. Clin Chem 1973;19:1329–38. https://doi.org/10.1093/clinchem/19.12.1329.Search in Google Scholar
28. Boyd, JC, Lacher, DA. The multivariate reference range: an alternative interpretation of multi-test profiles. Clin Chem 1982;28:259–65. https://doi.org/10.1093/clinchem/28.2.259.Search in Google Scholar
29. Solberg, HE. Multivariate reference regions. Scand J Clin Lab Invest Suppl 1995;222:3–5. https://doi.org/10.3109/00365519509088443.Search in Google Scholar PubMed
30. Hekking, M, Lindemans, J, Gelsema, ES. A computer program for constructing multivariate reference models. Comput Methods Progr Biomed 1997;53:191–200. https://doi.org/10.1016/s0169-2607(97)00018-7.Search in Google Scholar PubMed
31. Lado-Baleato, Ó, Cadarso-Suárez, C, Kneib, T, Gude, F. Multivariate reference and tolerance regions based on conditional transformation models: application to glycemic markers. Biom J 2023;65:e2200229. https://doi.org/10.1002/bimj.202200229.Search in Google Scholar PubMed
32. Hoermann, R, Larisch, R, Dietrich, JW, Midgley, JEM. Derivation of a multivariate reference range for pituitary thyrotropin and thyroid hormones: diagnostic efficiency compared with conventional single-reference method. Eur J Endocrinol 2016;174:735–43. https://doi.org/10.1530/eje-16-0031.Search in Google Scholar
33. Young, DS, Mathew, T. Nonparametric hyperrectangular tolerance and prediction regions for setting multivariate reference regions in laboratory medicine. Stat Methods Med Res 2020;29:3569–85. https://doi.org/10.1177/0962280220933910.Search in Google Scholar PubMed
34. Dong, X, Mathew, T. Central tolerance regions and reference regions for multivariate normal populations. J Multivariate Anal 2015;134:50–60. https://doi.org/10.1016/j.jmva.2014.10.009.Search in Google Scholar
35. Yakymiv, AL. Multivariate regular variation in probability theory. J Math Sci 2020;246:580–6. https://doi.org/10.1007/s10958-020-04763-8.Search in Google Scholar
36. Coskun, A. Bias in laboratory medicine: the dark side of the moon. Ann Lab Med 2024;44:6–20. https://doi.org/10.3343/alm.2024.44.1.6.Search in Google Scholar PubMed PubMed Central
37. Aarsand, AK, Webster, C, Fernandez-Calle, P, Jonker, N, Diaz-Garzon, J, Coskun, A, et al.. The EFLM biological variation database. https://biologicalvariation.eu/[Accessed August 2025].Search in Google Scholar
Supplementary Material
This article contains supplementary material (https://doi.org/10.1515/cclm-2025-0786).
© 2025 Walter de Gruyter GmbH, Berlin/Boston