{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,12]],"date-time":"2026-09-12T02:24:49Z","timestamp":1789179889843,"version":"build-2803163510"},"reference-count":63,"publisher":"MDPI AG","issue":"23","license":[{"start":{"date-parts":[[2025,12,4]],"date-time":"2025-12-04T00:00:00Z","timestamp":1764806400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100012550","name":"National Research, Development and Innovation Fund","doi-asserted-by":"publisher","award":["TKP2021-NKTA"],"award-info":[{"award-number":["TKP2021-NKTA"]}],"id":[{"id":"10.13039\/501100012550","id-type":"DOI","asserted-by":"publisher"}]},{"name":"University of Debrecen, Medical Faculty"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Nutrients"],"abstract":"<jats:p>Background\/Objectives: Big data analysis has revolutionized medical research, making it possible to analyze vast amounts of data and gain valuable insights that were previously impossible to obtain. Our knowledge of the characteristics of vitamin D sufficiency is primarily based on data from a limited number of observations, generally spanning a few years at most. Methods: Here at the Medical Faculty of the University of Debrecen, the big data approach has allowed us to analyze trends in vitamin D status using nearly 60,000 25-hydroxyvitamin D (25(OH)D) concentration results from 2000 onwards. Results: Apart from analyzing the well-known phenomenon of seasonality in 25(OH)D concentration, we observed a trend in test requests, which increased from a few hundred in 2000 to almost 10,000 in 2020. Of particular interest is the change in the gender gap in test requests. In previous years, test requests were primarily from women, but by the end of the analysis period, a significant number of requests were from men as well. Since the data set includes all age groups, we analyzed 25(OH)D concentration for incremental age sets of five years, from a few months to 100 years old. The prevalence of vitamin D insufficiency (&lt;75 nmol\/L) was clearly demarcated among various years of observation, age groups, sexes, and seasons. Our data was particularly valuable for analyzing the effect of the methodology used for 25(OH)D determination. Three different methodologies were used during the study period, and clear, statistically significant bias was observed. Conclusions: Our results clearly demonstrate the effect of the methodology used to determine 25(OH)D concentrations on vitamin D status, explicitly highlighting the urgent need to standardize the various platforms used to measure this important analyte and its consequences for public health.<\/jats:p>","DOI":"10.3390\/nu17233808","type":"journal-article","created":{"date-parts":[[2025,12,4]],"date-time":"2025-12-04T16:07:38Z","timestamp":1764864458000},"page":"3808","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Exploring Vitamin D Trends Through Big Data Analysis"],"prefix":"10.3390","volume":"17","author":[{"given":"Szilvia","family":"Racz","sequence":"first","affiliation":[{"name":"Department of Medical Imaging, Faculty of Medicine, Kalman Laki Doctoral School of the University of Debrecen, University of Debrecen, 4032 Debrecen, Hungary"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9884-9202","authenticated-orcid":false,"given":"Miklos","family":"Emri","sequence":"additional","affiliation":[{"name":"Department of Medical Imaging, Faculty of Medicine, University of Debrecen, 4032 Debrecen, Hungary"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ervin","family":"Berenyi","sequence":"additional","affiliation":[{"name":"Department of Medical Imaging, Faculty of Medicine, University of Debrecen, 4032 Debrecen, Hungary"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1466-7052","authenticated-orcid":false,"given":"Laszlo","family":"Horvath","sequence":"additional","affiliation":[{"name":"Department of Pharmaceutical Surveillance and Economics, Faculty of Pharmacy, University of Debrecen, 4032 Debrecen, Hungary"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0002-7188-2082","authenticated-orcid":false,"given":"Bela","family":"Toth","sequence":"additional","affiliation":[{"name":"Department of Pharmaceutical Surveillance and Economics, Faculty of Pharmacy, University of Debrecen, 4032 Debrecen, Hungary"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sandor","family":"Barat","sequence":"additional","affiliation":[{"name":"Department of Laboratory Medicine, Faculty of Medicine, University of Debrecen, 4032 Debrecen, Hungary"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Edit","family":"Kalina","sequence":"additional","affiliation":[{"name":"Department of Laboratory Medicine, Faculty of Medicine, University of Debrecen, 4032 Debrecen, Hungary"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Luca","family":"Jozsa","sequence":"additional","affiliation":[{"name":"Department of Laboratory Medicine, Faculty of Medicine, University of Debrecen, 4032 Debrecen, Hungary"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Amrit","family":"Bhattoa-Buzas","sequence":"additional","affiliation":[{"name":"Department of Laboratory Medicine, Faculty of Medicine, University of Debrecen, 4032 Debrecen, Hungary"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1439-3285","authenticated-orcid":false,"given":"William","family":"Grant","sequence":"additional","affiliation":[{"name":"Sunlight, Nutrition, and Health Research Center, 1745 Pacific Ave., Suite 504, San Francisco, CA 94109, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4909-0065","authenticated-orcid":false,"given":"Harjit","family":"Bhattoa","sequence":"additional","affiliation":[{"name":"Department of Laboratory Medicine, Faculty of Medicine, University of Debrecen, 4032 Debrecen, Hungary"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,12,4]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"737","DOI":"10.1111\/nure.12156","article-title":"Big data and systematic reviews in nutritional epidemiology","volume":"72","author":"Satija","year":"2014","journal-title":"Nutr. Rev."},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Gospodarska, E., Ghosh Dastidar, R., and Carlberg, C. (2023). Intervention Approaches in Studying the Response to Vitamin D3 Supplementation. Nutrients, 15.","DOI":"10.3390\/nu15153382"},{"key":"ref_3","doi-asserted-by":"crossref","unstructured":"Pilz, S., Trummer, C., Theiler-Schwetz, V., Grubler, M.R., Verheyen, N.D., Odler, B., Karras, S.N., Zittermann, A., and Marz, W. (2022). Critical Appraisal of Large Vitamin D Randomized Controlled Trials. Nutrients, 14.","DOI":"10.3390\/nu14020303"},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"3037","DOI":"10.1007\/s00394-019-02142-x","article-title":"Time trends of vitamin D concentrations in northern Sweden between 1986 and 2014: A population-based cross-sectional study","volume":"59","author":"Summerhays","year":"2020","journal-title":"Eur. J. Nutr."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"1519","DOI":"10.3945\/ajcn.2008.26182","article-title":"Serum 25-hydroxyvitamin D status of the US population: 1988\u20131994 compared with 2000\u20132004","volume":"88","author":"Looker","year":"2008","journal-title":"Am. J. Clin. Nutr."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"97","DOI":"10.1210\/jc.2012-2643","article-title":"Variability and reproducibility of circulating vitamin D in a nationwide U.S. population","volume":"98","author":"Major","year":"2013","journal-title":"J. Clin. Endocrinol. Metab."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"670","DOI":"10.1016\/j.clinbiochem.2014.02.004","article-title":"Seasonal vitamin D changes and the impact on health risk assessment","volume":"47","author":"Rosecrans","year":"2014","journal-title":"Clin. Biochem."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"113","DOI":"10.1515\/jomb-2015-0014","article-title":"Blood Sampling Seasonality as an Important Preanalytical Factor for Assessment of Vitamin D Status","volume":"35","author":"Bonelli","year":"2016","journal-title":"J. Med. Biochem."},{"key":"ref_9","first-page":"409","article-title":"Seasonal variation of serum vitamin D among Greek female patients with osteoporosis","volume":"29","author":"Papadakis","year":"2015","journal-title":"In Vivo"},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"860","DOI":"10.1093\/ajcn\/85.3.860","article-title":"Hypovitaminosis D in British adults at age 45 y: Nationwide cohort study of dietary and lifestyle predictors","volume":"85","author":"Hypponen","year":"2007","journal-title":"Am. J. Clin. Nutr."},{"key":"ref_11","doi-asserted-by":"crossref","unstructured":"Kroll, M.H., Bi, C., Garber, C.C., Kaufman, H.W., Liu, D., Caston-Balderrama, A., Zhang, K., Clarke, N., Xie, M., and Reitz, R.E. (2015). Temporal relationship between vitamin D status and parathyroid hormone in the United States. PLoS ONE, 10.","DOI":"10.1371\/journal.pone.0118108"},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"548","DOI":"10.1007\/BF03654812","article-title":"Vitamin D concentration and deficiency across different ages and genders","volume":"24","author":"Lippi","year":"2012","journal-title":"Aging Clin. Exp. Res."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"1003","DOI":"10.1177\/14034948221092287","article-title":"Low vitamin D levels among children and adolescents in an Arctic population","volume":"51","author":"Malyavskaya","year":"2023","journal-title":"Scand. J. Public Health"},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"248","DOI":"10.4274\/jcrpe.galenos.2019.2019.0097","article-title":"Vitamin D Status Across Age Groups in Turkey: Results of 108,742 Samples from a Single Laboratory","volume":"12","author":"Aksu","year":"2020","journal-title":"J. Clin. Res. Pediatr. Endocrinol."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"713","DOI":"10.1007\/s00198-005-1867-7","article-title":"Estimates of optimal vitamin D status","volume":"16","author":"Heaney","year":"2005","journal-title":"Osteoporos. Int."},{"key":"ref_16","doi-asserted-by":"crossref","unstructured":"Smirnova, D.V., Rehm, C.D., Fritz, R.D., Kutepova, I.S., Soshina, M.S., and Berezhnaya, Y.A. (2022). Vitamin D status of the Russian adult population from 2013 to 2018. Sci. Rep., 12.","DOI":"10.1038\/s41598-022-21221-4"},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"1044","DOI":"10.3945\/ajcn.114.103689","article-title":"Standardizing 25-hydroxyvitamin D values from the Canadian Health Measures Survey","volume":"102","author":"Sarafin","year":"2015","journal-title":"Am. J. Clin. Nutr."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"454","DOI":"10.3945\/ajcn.115.127985","article-title":"The vitamin D status of the US population from 1988 to 2010 using standardized serum concentrations of 25-hydroxyvitamin D shows recent modest increases","volume":"104","author":"Schleicher","year":"2016","journal-title":"Am. J. Clin. Nutr."},{"key":"ref_19","doi-asserted-by":"crossref","unstructured":"Rabenberg, M., Scheidt-Nave, C., Busch, M.A., Thamm, M., Rieckmann, N., Durazo-Arvizu, R.A., Dowling, K.G., Skrabakova, Z., Cashman, K.D., and Sempos, C.T. (2018). Implications of standardization of serum 25-hydroxyvitamin D data for the evaluation of vitamin D status in Germany, including a temporal analysis. BMC Public Health, 18.","DOI":"10.1186\/s12889-018-5769-y"},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"716","DOI":"10.1016\/j.nutres.2015.06.005","article-title":"Vitamin D deficiency is common among adults in Wallonia (Belgium, 51 degrees 30\u2019 North): Findings from the Nutrition, Environment and Cardio-Vascular Health study","volume":"35","author":"Hoge","year":"2015","journal-title":"Nutr. Res."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"1079","DOI":"10.1038\/sj.ejcn.1602825","article-title":"Vitamin D status and health correlates among German adults","volume":"62","author":"Hintzpeter","year":"2008","journal-title":"Eur. J. Clin. Nutr."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"1186","DOI":"10.1017\/S1368980018003816","article-title":"Vitamin D status in a multi-ethnic population of northern Norway: The SAMINOR 2 Clinical Survey","volume":"23","author":"Petrenya","year":"2020","journal-title":"Public Health Nutr."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"163","DOI":"10.1530\/EC-15-0037","article-title":"Rising trend in vitamin D status from 1993 to 2013: Dual concerns for the future","volume":"4","author":"McKenna","year":"2015","journal-title":"Endocr. Connect."},{"key":"ref_24","doi-asserted-by":"crossref","unstructured":"Nielsen, N.O., Jorgensen, M.E., Friis, H., Melbye, M., Soborg, B., Jeppesen, C., Lundqvist, M., Cohen, A., Hougaard, D.M., and Bjerregaard, P. (2014). Decrease in vitamin D status in the Greenlandic adult population from 1987\u20132010. PLoS ONE, 9.","DOI":"10.1371\/journal.pone.0112949"},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"626","DOI":"10.1001\/archinternmed.2008.604","article-title":"Demographic differences and trends of vitamin D insufficiency in the US population, 1988\u20132004","volume":"169","author":"Ginde","year":"2009","journal-title":"Arch. Intern. Med."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"150","DOI":"10.1093\/ajcn\/nqz037","article-title":"Vitamin D status in the United States, 2011\u20132014","volume":"110","author":"Herrick","year":"2019","journal-title":"Am. J. Clin. Nutr."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"1711","DOI":"10.1007\/s00394-018-1717-y","article-title":"No improvement in vitamin D status in German infants and adolescents between 2009 and 2014 despite public recommendations to increase vitamin D intake in 2012","volume":"58","author":"Kunz","year":"2019","journal-title":"Eur. J. Nutr."},{"key":"ref_28","doi-asserted-by":"crossref","unstructured":"Horvath, L., Mirani, S., Girgis, M.M.F., Racz, S., Bacskay, I., Bhattoa, H.P., and Toth, B.E. (2023). Six years\u2019 experience and trends of serum 25-hydroxy vitamin D concentration and the effect of vitamin D3 consumption on these trends. Front. Pharmacol., 14.","DOI":"10.3389\/fphar.2023.1232285"},{"key":"ref_29","doi-asserted-by":"crossref","unstructured":"Tuuminen, T., Sorsa, M., Tornudd, M., Lahteenmaki, P.L., Poussa, T., Suonsivu, P., Pitkanen, E.M., Antila, E., and Jaakkola, K. (2022). Long-term nutritional trends in the Finnish population estimated from a large laboratory database from 1987 to 2020. Sci. Rep., 12.","DOI":"10.1038\/s41598-022-09131-x"},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"363","DOI":"10.1007\/s11154-016-9404-x","article-title":"Vitamin D: Musculoskeletal health","volume":"18","author":"Bhattoa","year":"2017","journal-title":"Rev. Endocr. Metab. Disord."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"577","DOI":"10.1016\/j.ijcard.2016.12.053","article-title":"Vitamin D and cardiovascular disease: From atherosclerosis to myocardial infarction and stroke","volume":"230","author":"Muscogiuri","year":"2017","journal-title":"Int. J. Cardiol."},{"key":"ref_32","doi-asserted-by":"crossref","unstructured":"Munoz, A., and Grant, W.B. (2022). Vitamin D and Cancer: An Historical Overview of the Epidemiology and Mechanisms. Nutrients, 14.","DOI":"10.3390\/nu14071448"},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"5","DOI":"10.1016\/j.jsbmb.2017.01.003","article-title":"Seasonal variations of U.S. mortality rates: Roles of solar ultraviolet-B doses, vitamin D, gene exp ression, and infections","volume":"173","author":"Grant","year":"2017","journal-title":"J. Steroid Biochem. Mol. Biol."},{"key":"ref_34","doi-asserted-by":"crossref","unstructured":"Grant, W.B., Fakhoury, H.M.A., Karras, S.N., Al Anouti, F., and Bhattoa, H.P. (2019). Variations in 25-Hydroxyvitamin D in Countries from the Middle East and Europe: The Roles of UVB Exposure and Diet. Nutrients, 11.","DOI":"10.3390\/nu11092065"},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"1911","DOI":"10.1210\/jc.2011-0385","article-title":"Evaluation, treatment, and prevention of vitamin D deficiency: An Endocrine Society clinical practice guideline","volume":"96","author":"Holick","year":"2011","journal-title":"J. Clin. Endocrinol. Metab."},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"1907","DOI":"10.1210\/clinem\/dgae290","article-title":"Vitamin D for the Prevention of Disease: An Endocrine Society Clinical Practice Guideline","volume":"109","author":"Demay","year":"2024","journal-title":"J. Clin. Endocrinol. Metab."},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"18","DOI":"10.1093\/ajcn\/84.1.18","article-title":"Estimation of optimal serum concentrations of 25-hydroxyvitamin D for multiple health outcomes","volume":"84","author":"Giovannucci","year":"2006","journal-title":"Am. J. Clin. Nutr."},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"305","DOI":"10.1359\/jbmr.090728","article-title":"Bone mineralization defects and vitamin D deficiency: Histomorphometric analysis of iliac crest bone biopsies and circulating 25-hydroxyvitamin D in 675 patients","volume":"25","author":"Priemel","year":"2010","journal-title":"J. Bone Miner. Res."},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"1340","DOI":"10.1001\/archinte.168.12.1340","article-title":"Independent association of low serum 25-hydroxyvitamin d and 1,25-dihydroxyvitamin d levels with all-cause and cardiovascular mortality","volume":"168","author":"Dobnig","year":"2008","journal-title":"Arch. Intern. Med."},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"521","DOI":"10.2337\/dc14-0180","article-title":"Serum 25-hydroxyvitamin D: A predictor of macrovascular and microvascular complications in patients with type 2 diabetes","volume":"38","author":"Herrmann","year":"2015","journal-title":"Diabetes Care"},{"key":"ref_41","doi-asserted-by":"crossref","unstructured":"Grant, W.B., Boucher, B.J., Cheng, R.Z., Pludowski, P., and Wimalawansa, S.J. (2025). Vitamin D and Cardiovascular Health: A Narrative Review of Risk Reduction Evidence. Nutrients, 17.","DOI":"10.3390\/nu17132102"},{"key":"ref_42","doi-asserted-by":"crossref","unstructured":"Grant, W.B., Wimalawansa, S.J., Pludowski, P., and Cheng, R.Z. (2025). Vitamin D: Evidence-Based Health Benefits and Recommendations for Population Guidelines. Nutrients, 17.","DOI":"10.3390\/nu17020277"},{"key":"ref_43","doi-asserted-by":"crossref","first-page":"73","DOI":"10.1016\/j.annepidem.2007.12.001","article-title":"Vitamin D Status: Measurement, Interpretation, and Clinical Application","volume":"19","author":"Holick","year":"2009","journal-title":"Ann. Epidemiol."},{"key":"ref_44","doi-asserted-by":"crossref","first-page":"2443","DOI":"10.1359\/jbmr.2000.15.12.2443","article-title":"Circaannual rhythms and interactions of vitamin D metabolites, parathyroid hormone, and biochemical markers of skeletal homeostasis: A prospective study","volume":"15","author":"Woitge","year":"2000","journal-title":"J. Bone Miner. Res."},{"key":"ref_45","doi-asserted-by":"crossref","first-page":"g3656","DOI":"10.1136\/bmj.g3656","article-title":"Vitamin D and mortality: Meta-analysis of individual participant data from a large consortium of cohort studies from Europe and the United States","volume":"348","author":"Schottker","year":"2014","journal-title":"BMJ"},{"key":"ref_46","doi-asserted-by":"crossref","first-page":"367","DOI":"10.1007\/s00394-013-0634-3","article-title":"Vitamin D supplementation, body weight and human serum 25-hydroxyvitamin D response: A systematic review","volume":"53","author":"Zittermann","year":"2014","journal-title":"Eur. J. Nutr."},{"key":"ref_47","doi-asserted-by":"crossref","first-page":"870","DOI":"10.1016\/j.bone.2009.07.015","article-title":"Serum 25-hydroxyvitamin D levels in vitamin D-insufficient hip fracture patients after supplementation with ergocalciferol and cholecalciferol","volume":"45","author":"Glendenning","year":"2009","journal-title":"Bone"},{"key":"ref_48","doi-asserted-by":"crossref","first-page":"69","DOI":"10.1007\/s00223-013-9729-3","article-title":"The effect of high-dose vitamin D supplementation on calciotropic hormones and bone mineral density in obese subjects with low levels of circulating 25-hydroxyvitamin d: Results from a randomized controlled study","volume":"93","author":"Wamberg","year":"2013","journal-title":"Calcif. Tissue Int."},{"key":"ref_49","doi-asserted-by":"crossref","first-page":"1101","DOI":"10.1007\/s00198-012-1944-7","article-title":"Effect of oral cholecalciferol 2,000 versus 5,000 IU on serum vitamin D, PTH, bone and muscle strength in patients with vitamin D deficiency","volume":"24","author":"Diamond","year":"2013","journal-title":"Osteoporos. Int."},{"key":"ref_50","doi-asserted-by":"crossref","unstructured":"Rybchyn, M.S., Abboud, M., Puglisi, D.A., Gordon-Thomson, C., Brennan-Speranza, T.C., Mason, R.S., and Fraser, D.R. (2020). Skeletal Muscle and the Maintenance of Vitamin D Status. Nutrients, 12.","DOI":"10.20944\/preprints202008.0685.v1"},{"key":"ref_51","doi-asserted-by":"crossref","first-page":"nzz087","DOI":"10.1093\/cdn\/nzz087","article-title":"The Role of Skeletal Muscle in Maintaining Vitamin D Status in Winter","volume":"3","author":"Mason","year":"2019","journal-title":"Curr. Dev. Nutr."},{"key":"ref_52","doi-asserted-by":"crossref","first-page":"3149","DOI":"10.1210\/jc.2004-0682","article-title":"Editorial: The determination of circulating 25-hydroxyvitamin D: No easy task","volume":"89","author":"Hollis","year":"2004","journal-title":"J. Clin. Endocrinol. Metab."},{"key":"ref_53","doi-asserted-by":"crossref","first-page":"171","DOI":"10.1016\/j.cca.2021.03.002","article-title":"Recommendations on the measurement and the clinical use of vitamin D metabolites and vitamin D binding protein\u2014A position paper from the IFCC Committee on bone metabolism","volume":"517","author":"Makris","year":"2021","journal-title":"Clin. Chim. Acta"},{"key":"ref_54","doi-asserted-by":"crossref","first-page":"45","DOI":"10.1515\/cclm-2014-1249","article-title":"Performance characteristics of the VIDAS(R) 25-OH Vitamin D Total assay-comparison with four immunoassays and two liquid chromatography-tandem mass spectrometry methods in a multicentric study","volume":"54","author":"Moreau","year":"2016","journal-title":"Clin. Chem. Lab. Med."},{"key":"ref_55","doi-asserted-by":"crossref","first-page":"255","DOI":"10.1016\/j.cca.2012.10.056","article-title":"Accuracy of three automated 25-hydroxyvitamin D assays in hemodialysis patients","volume":"415","author":"Depreter","year":"2013","journal-title":"Clin. Chim. Acta"},{"key":"ref_56","doi-asserted-by":"crossref","first-page":"543","DOI":"10.1373\/clinchem.2011.176545","article-title":"Accuracy of 6 routine 25-hydroxyvitamin D assays: Influence of vitamin D binding protein concentration","volume":"58","author":"Heijboer","year":"2012","journal-title":"Clin. Chem."},{"key":"ref_57","doi-asserted-by":"crossref","first-page":"60","DOI":"10.1016\/j.cca.2014.01.026","article-title":"Evaluation of automated immunoassays for 25(OH)-vitamin D determination in different critical populations before and after standardization of the assays","volume":"431","author":"Cavalier","year":"2014","journal-title":"Clin. Chim. Acta"},{"key":"ref_58","doi-asserted-by":"crossref","first-page":"1709","DOI":"10.1002\/jbmr.2252","article-title":"Standardizing vitamin D assays: The way forward","volume":"29","author":"Binkley","year":"2014","journal-title":"J. Bone Miner. Res."},{"key":"ref_59","doi-asserted-by":"crossref","first-page":"115","DOI":"10.1016\/j.jsbmb.2015.08.027","article-title":"Developing vitamin D dietary guidelines and the lack of 25-hydroxyvitamin D assay standardization: The ever-present past","volume":"164","author":"Sempos","year":"2016","journal-title":"J. Steroid Biochem. Mol. Biol."},{"key":"ref_60","doi-asserted-by":"crossref","first-page":"549","DOI":"10.3109\/00365513.2015.1057898","article-title":"Standardizing serum 25-hydroxyvitamin D data from four Nordic population samples using the Vitamin D Standardization Program protocols: Shedding new light on vitamin D status in Nordic individuals","volume":"75","author":"Cashman","year":"2015","journal-title":"Scand. J. Clin. Lab. Investig."},{"key":"ref_61","doi-asserted-by":"crossref","first-page":"1235","DOI":"10.3945\/ajcn.112.057182","article-title":"Evaluation of Vitamin D Standardization Program protocols for standardizing serum 25-hydroxyvitamin D data: A case study of the program\u2019s potential for national nutrition and health surveys","volume":"97","author":"Cashman","year":"2013","journal-title":"Am. J. Clin. Nutr."},{"key":"ref_62","doi-asserted-by":"crossref","first-page":"1653","DOI":"10.1007\/s00198-017-3924-4","article-title":"Standardizing 25-hydroxyvitamin D data from the HunMen cohort","volume":"28","author":"Jakab","year":"2017","journal-title":"Osteoporos. Int."},{"key":"ref_63","doi-asserted-by":"crossref","first-page":"231","DOI":"10.1038\/s41430-019-0553-3","article-title":"Vitamin D testing: Advantages and limits of the current assays","volume":"74","author":"Altieri","year":"2020","journal-title":"Eur. J. Clin. 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