Vitamin D Standardization Program (VDSP) Symposium: Tools to Improve Laboratory Measurement

This workshop was held on November 14, 2013, in Gaithersburg, Maryland.


The Office of Dietary Supplements (ODS), National Institutes of Health, established the Vitamin D Standardization Program (VDSP) in November 2010 to standardize the laboratory measurement of vitamin D status worldwide. Standardization is essential to improve the detection, evaluation, and treatment of vitamin D deficiency and insufficiency by making measurements of serum total 25-hydroxyvitamin D [25(OH)D] accurate and comparable over time, location, and laboratory procedure. ODS leads this collaborative effort with the National Institute of Standards and Technology (NIST); the Centers for Disease Control and Prevention (CDC); the Laboratory for Analytical Chemistry of Ghent University, Belgium; and the Vitamin D External Quality Assessment Scheme (DEQAS), U.K.; and the College of American Pathologists (CAP). Key VDSP participants also include the national health surveys from Australia, Canada, Germany, Ireland, Mexico, South Korea, the United Kingdom, and the United States; numerous consultants from around the world also participated. VDSP is part of the ODS Vitamin D Initiative.

Symposium Goals and Participants

The VDSP Symposium, attended by approximately 100 people in-person and by more than 200 via Webinar, included representatives from commercial assay manufacturers; commercial, clinical and research laboratory personnel; vitamin D researchers; and members of professional societies with clinical and public health interest in vitamin D. In addition to presentations of the goals and components of the VDSP, the symposium included:

  • Data from VDSP inter-laboratory comparison and commutability studies;
  • Demonstration of how tools developed through VDSP can be used to improve the standardization of vitamin D measurement around the world; and
  • Gathering of feedback as to how VDSP can be improved to meet the needs of attendees.


ODS, NIST, the American Association for Clinical Chemistry (AACC) and the Partnership for the Accurate Testing of Hormones (PATH) co-sponsored this 1-day symposium, also held under the auspices of the International Federation of Clinical Chemistry and Laboratory Medicine (IFCC).

Symposium Products