Issues of methodology, standardization and metabolite recognition for 25-hydroxyvitamin D when comparing the DiaSorin radioimmunoassay and the Nichols Advantage automated chemiluminescence protein-binding assay in hip fracture cases - Glendenning, P; Noble, J M; Taranto, M; Musk, A A; McGuiness, M; Goldswain, P R; Fraser, W D; Vasikaran, S D (Ann Clin Biochem, 2003)