Influence of Vitamin D Binding Protein on Accuracy of 25-Hydroxyvitamin D Measurement Using the ADVIA Centaur Vitamin D Total Assay

Table 3

Serum concentrations of DBP in healthy subjects and DBP-spiked samples from healthy subjects.

LC-MS/MS (ng/mL)	Concentration of spiked DBP in serum (μg/mL)	DBP (mg/mL)	ADVIA Centaur (ng/mL)	ADVIA Centaur bias to LC-MS/MS
24		276.9	24.3	1%
24	50	347.2	24.2	1%
24	100	385.5	23.5	−2%
24	150	334.9	24.3	1%
24	200	407.1	23.1	−4%
24	250	472.1	22.9	−5%
32		301.6	31.6	−1%
32	50	339.1	34.8	9%
32	100	629.7	33	3%
32	150	446.8	34.8	9%
32	200	489.5	34.5	8%
32	250	584.4	31.9	0%
51		260.7	53	4%
51	50	261.2	48.4	−5%
51	100	327.8	47.5	−7%
51	150	417.7	50.8	0%
51	200	593.3	49.1	−4%
51	250	486.2	45.7	−10%
41		380.1	39.7	−3%
41	50	420.5	40.6	−1%
41	100	590.2	41.2	0%
41	150	747.3	38.5	−6%
41	200	738	40.9	0%
41	250	980.6	37.7	−8%
75		519	75.3	0%
75	50	584.8	69.7	−7%
75	100	724.9	75.3	0%
75	150	788.4	73.4	−2%
75	200	731.3	67.7	−10%
75	250	789.7	73.1	−2%

DBP: vitamin D binding protein. To convert 25(OH)D concentrations to nanomoles per liter (nmol/L), multiply by 2.5.