Measurements of 25-hydroxyvitamin D concentrations in archived dried blood spots are reliable and accurately reflect those in Plasma

Abstract

Context: Recognition that vitamin D might be associated with many chronic diseases has led to large-scale epidemiological and clinical studies. Dried blood spots (DBS) are a useful resource for these studies. Consequently, accurate, efficient, and inexpensive assays to quantify 25-hydroxyvitamin D (25OHD) in DBS are required. CopyrightObjective: This study evaluated the validityandreliability of a liquid chromatography-tandem mass spectrometry assay for measuring 25OHD in archived DBS and compared measurements of 25OHD in DBS with those in plasma.Design and Participants: Sixty-two participants in the Melbourne Collaborative Cohort Study who had plasma and matching DBS stored since study entr..