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Baseline Assessment of 25-Hydroxyvitamin D Assay Performance: A Vitamin D Standardization Program (VDSP) Interlaboratory Comparison Study



Christopher T. Sempos, Stephen Wise, Karen W. Phinney, Susan Tai, Johanna Camara, Gary L. Myers, Ramon Durazo-Arvizu, Lu Tian, John H. Eckfeldt, Andrew N. Hoofnagle, W. Greg Miller, Lorin M. Bachmann, Ian S. Young, J Pettit, G. Caldwell, A Liu, S P. Brooks, K. Sarafin, M. Thamm, C. Scheidt-Nave, G. B. Mensink, M. Busch, M. Rabenberg, Kevin Cashman, Mairead Kiely, Michael Kinsella, K Galvan, J. Y. Zhang, K OH, S. W. Lee, C. L. Jung, L. Cox, G. Goldberg, K. Guberg, S. Meadows, A. Prentice, G. Swan, A. Tedstone, Graham D. Carter, Julia C. Jones, P. Brannon, R. M. Lucas, P. M. Crump, Glenville Jones, E. Cavalier, Joyce Merkel, J. M. Betz


The Vitamin D Standardization Program (VDSP) coordinated an interlaboratory study to assess the comparability of measurements of total 25-hydroxyvitamin D [25(OH)D] in human serum, which is the primary marker of vitamin D status. A set of 50 individual donor samples were analyzed by 15 different laboratories representing national nutrition surveys, assay manufacturers, and clinical/research laboratories to provide results for total 25(OH)D using both immunoassays and liquid chromatography – tandem mass spectrometry. The results were evaluated relative to bias compared to the target values assigned based on a combination of measurements at the University of Ghent (Belgium) and the U.S. National Institute of Standards and Technology (NIST) using reference measurement procedures for determination of 25(OH)D2 and 25(OH)D3. The CV% and % mean bias for each laboratory and assay platform were assessed and compared to previously established VDSP performance criteria of CV ≤ 10 % and mean bias ≤ 5 %. Nearly all LC-MS/MS results achieved the VDSP criteria, whereas only 50 % of the immunoassays met the criterion for CV ≤ 10 % and only three of eight immunoassays achieved the ≤ 5 % bias. These results establish a benchmark for evaluation of 25(OH)D assay performance and standardization activities in the future.
Journal of Aoac International


Standard Reference Material (SRM), liquid chromatography – tandem mass spectrometry (LC-MS/MS), immunoassay, reference measurement procedure (RMP), 25-hydroxyvitamin D3, 25-hydroxyvitamin D2, total 25-hydroxyvitamin D


Sempos, C. , Wise, S. , Phinney, K. , Tai, S. , Camara, J. , Myers, G. , Durazo-Arvizu, R. , Tian, L. , Eckfeldt, J. , Hoofnagle, A. , Miller, W. , Bachmann, L. , Young, I. , Pettit, J. , Caldwell, G. , Liu, A. , Brooks, S. , Sarafin, K. , Thamm, M. , Scheidt-Nave, C. , Mensink, G. , Busch, M. , Rabenberg, M. , Cashman, K. , Kiely, M. , Kinsella, M. , Galvan, K. , Zhang, J. , OH, K. , Lee, S. , Jung, C. , Cox, L. , Goldberg, G. , Guberg, K. , Meadows, S. , Prentice, A. , Swan, G. , Tedstone, A. , Carter, G. , Jones, J. , Brannon, P. , Lucas, R. , Crump, P. , Jones, G. , Cavalier, E. , Merkel, J. and Betz, J. (2017), Baseline Assessment of 25-Hydroxyvitamin D Assay Performance: A Vitamin D Standardization Program (VDSP) Interlaboratory Comparison Study, Journal of Aoac International, [online], (Accessed July 17, 2024)


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Created August 18, 2017, Updated October 13, 2022