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DEQAS Certificate

The 25OH Vitamin D Total ELISA (KAP1971) was recently awarded the Certificate of Proficiency by the Vitamin D External Quality Assessment Scheme (DEQAS) Advisory Panel.

This Certificate warrants that the DIAsource 25OH Vitamin D Total ELISA assay has met the performance targets set by the DEQAS Advisory Panel.

The DEQAS Advisory Panel performance targets call for 75% or more of the results falling within ± 25% of the Target Value (the NIST LC-MS/MS assigned value). The DIAsource 25OH Vitamin D Total ELISA has exceeded these targets by establishing more than 90% of the results within the targets, with a mean bias of -1% against the reference NIST LC-MS/MS method.

This is the result of our work to calibrate the DIAsource 25OH Vitamin D Total ELISA assay against the reference method ID-LC/MS-MS (Ghent University) according to the VDSP -  Vitamin D Standardization Program.

The international Vitamin D Quality Assessment Scheme (DEQAS) has been monitoring the performance of 25OH Vitamin D assays since 1989 and now has >1000 registered participants worldwide. In essence DEQAS is an ongoing multicenter trial of the methods used by its participants and provides a unique opportunity to assess the accuracy and specificity of 25OH Vitamin D methods as well as the analytical performance of a large number of their users.

Vitamin D

The measurement of 25OH Vitamin D concentration in the serum or plasma is so far the best indicator of Vitamin D nutritional status. It is generally accepted that serum 25OH Vitamin D levels reflect the body’s storage levels of Vitamin D and correlate with the clinical symptoms of Vitamin D deficiency.

Since many years the role of vitamin D in bone and mineral metabolism was recognized in bone-related diseases. Clinical applications of 25OH Vitamin D measurements were merely related to the diagnosis and monitoring of therapy for rickets (children), osteomalacia, postmenopausal osteoporosis, and renal osteodystrophy. As a results of more recent studies a link between Vitamin D deficiency and many other diseases is suggested. These include cancer, cardiovascular disease, autoimmune diseases, diabetes, depression and many others.


DIAsource ImmunoAssays SA
BE 0457.934.723
Rue du Bosquet, 2 | 1348 Louvain-la-Neuve - Belgium
Tel +32 10 84 99 11 | Fax +32 10 84 99 90

CLOSING DAYS 2019 : 1/01-22/04-01&30/05-10/06-21/07-15/08-01&11/11-25/12

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DIAsource ImmunoAssays (formerly BioSource), experienced diagnostic manufacturer of RIA-ELISA-LIA immunoassays, validation on automates, large scale production of Antibodies-Point of Care Tests.

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