biostudies-literatureCamara JEIntramural NIH HHSNational Institutes of Health5067-5084https://www.ebi.ac.uk/biostudies/studies/S-EPMC8431775biostudies-literatureUnknown413(20)An interlaboratory study was conducted through the Vitamin D Standardization Program (VDSP) to assess commutability of Standard Reference Materials® (SRMs) and proficiency testing/external quality assessment (PT/EQA) samples for determination of serum total 25-hydroxyvitamin D [25(OH)D] using ligand binding assays and liquid chromatography-tandem mass spectrometry (LC-MS/MS). A set of 50 single-donor serum samples were assigned target values for 25-hydroxyvitamin D<sub>2</sub> [25(OH)D<sub>2</sub>] and 25-hydroxyvitamin D<sub>3</sub> [25(OH)D<sub>3</sub>] using reference measurement procedures (RMPs). SRM and PT/EQA samples evaluated included SRM 972a (four levels), SRM 2973, six College of American Pathologists (CAP) Accuracy-Based Vitamin D (ABVD) samples, and nine Vitamin D External QuaAnalytical and bioanalytical chemistryAssessment of serum total 25-hydroxyvitamin D assay commutability of Standard Reference Materials and College of American Pathologists Accuracy-Based Vitamin D (ABVD) Scheme and Vitamin D External Quality Assessment Scheme (DEQAS) materials: Vitamin D Standardization Program (VDSP) Commutability Study 2.PMC8431775Z99 OD999999Pham HSimpson CCarter GDKhan DACavalier EBatista MCHolmquist BParker NPopp CKuszak AJTourneur CHo CSFreeman JMeadows SFischer RSimard JNFitzgerald RMerkel JMushtaq SYuan JBreen NVillarreal AJones JPease CBeckert CCamara JEHoofnagle ANSempos CTWise SALaw EWKWilliams ELClarke MWNalin FRobyak KSchultess JLukas PKilbane MBennett AHahm GGonthier RJansen EBurdette CQCreer MHVan Slooten Gvan den Ouweland JMWDurazo-Arvizu RAKaul RIvison FCox LTwomey PJfalseAssessment of serum total 25-hydroxyvitamin D assay commutability of Standard Reference Materials and College of American Pathologists Accuracy-Based Vitamin D (ABVD) Scheme and Vitamin D External Quality Assessment Scheme (DEQAS) materials: Vitamin D Standardization Program (VDSP) Commutability Study 2.An interlaboratory study was conducted through the Vitamin D Standardization Program (VDSP) to assess commutability of Standard Reference Materials® (SRMs) and proficiency testing/external quality assessment (PT/EQA) samples for determination of serum total 25-hydroxyvitamin D [25(OH)D] using ligand binding assays and liquid chromatography-tandem mass spectrometry (LC-MS/MS). A set of 50 single-donor serum samples were assigned target values for 25-hydroxyvitamin D<sub>2</sub> [25(OH)D<sub>2</sub>] and 25-hydroxyvitamin D<sub>3</sub> [25(OH)D<sub>3</sub>] using reference measurement procedures (RMPs). SRM and PT/EQA samples evaluated included SRM 972a (four levels), SRM 2973, six College of American Pathologists (CAP) Accuracy-Based Vitamin D (ABVD) samples, and nine Vitamin D External Qua2021-01-01T00:00:00Z2021 Aug2025-04-04T09:37:02.955Z2025-04-04T09:37:02.955ZS-EPMC84317753418410210.1007/s00216-021-03470-w