. 2017 Sep 27;102(12):4496–4505. doi: 10.1210/jc.2017-01179

Table 2.

Serum 25(OH)D by Daily D Dose Group During 6 Months’ Supplementation With 600, 1000, or 2000 IU/d of Vitamin D₃ and 6 Months After Supplementation (12 Months)^a

	Baseline	3 Months	6 Months	12 Months
Serum 25(OH)D, ng/mL
600 IU^b	21.9 (0.5)	25.6 (0.6)	26.3 (0.6)	24.8 (0.6)
1000 IU^c	21.7 (0.5)	26.6 (0.6)	27.5 (0.7)	24.5 (0.6)
2000 IU^d	22.4 (0.5)	33.1 (0.6)	33.1 (0.6)	26.3 (0.6)
P value among dose groups	0.59	<0.001	<0.001	0.07

^{^a}

Values are means (standard errors). Estimates are from a linear mixed model with repeated measurements at three time points (3, 6, and 12 months), three dose groups (600, 1000, and 2000 IU), and unstructured covariance structure.

^{^b}

n = 207, 199, 188, and 188 at baseline, 3, 6, and 12 months, respectively.

^{^c}

n = 190, 189, 173, and 173 at baseline, 3, 6, and 12 months, respectively.

^{^d}

n = 207, 202, 190, and 190 at baseline, 3, 6, and 12 months, respectively.