Table 1. Precision results of 25-OH-D2, 25-OH-D3, and tD control levels.

Control	Compound	Expected (ng/mL)	Mean (ng/mL)	SDa	%CVb	%Bias	SEc
1	25-OH-D2	9.20	9.30	0.35	3.80	0.90	0.04
	25-OH-D3	10.10	10.08	0.36	3.52	0.67	0.04
	tD	19.30	19.45	0.36	1.83	0.78	0.04
2	25-OH-D2	28.00	28.04	0.94	3.36	0.14	0.10
	25-OH-D3	30.30	29.55	0.72	2.44	-0.92	0.08
	tD	58.30	57.59	0.83	1.44	-1.22	0.09
3	25-OH-D2	83.80	82.79	2.25	2.72	-1.20	0.23
	25-OH-D3	89.30	87.87	1.70	1.94	-1.60	0.18
	tD	173.10	170.66	1.98	1.16	-1.41	0.21

Precision result of 92 Cascadion 25-hydroxyvitamin D control levels. Data were acquired over the period of 8/3/2020 to 12/4/2020. Expected and mean values are in ng/mL.

^aStandard deviation

^bCoefficient variance percentage.

^cStandard error.