title: Standardization of vitamin D assays: art or science?
authors.forename: William D
authors.initials: WD
authors.lastname: Fraser
mesh_terms: D001681:Biological Assay / Q000379:methods* / Q000592:standards*; D002853:Chromatography, Liquid / Q000379:methods* / Q000592:standards; D006801:Humans; D015203:Reproducibility of Results; D053719:Tandem Mass Spectrometry / Q000379:methods / Q000592:standards; D014807:Vitamin D / Q000031:analogs & derivatives* / Q000097:blood
chemical_list: D014807:Vitamin D; C104450:25-hydroxyvitamin D