Table 3.

Change in Total Body Iron (mg/interval) at three consecutive adjacent intervals after blood donation: Mean (95% CI) change for donors with at least 6 follow-up hemoglobin values. P: p value for comparing changes among intervals

Weeks after donation	interval	≤26 ng/mL		>26 ng/mL
		Iron	No Iron	Iron	No Iron
0 to 8 weeks	1	367.8	−24.1	167.8	−68.1
95% CI		(293.5, 442.1)	(−82.5, 34.3)	(116.4, 219.2)	(−136.7, 0.5)
8 to 16 weeks	2	183.9	138.3	129.8	140.9
95% CI		(132.2, 235.6)	(87.7, 188.9)	(81.8, 177.8)	(75.6, 206.2)
16 to 24 weeks	3	90.0	81.6	66.0	65.2
95% CI		(44.1, 135.9)	(27.9, 135.3)	(13.9, 118.1)	(4.6, 125.8)
P	overall	<0.0001	<0.0001	<0.0001	<0.0001
	1 vs 2	0.0001	0.0003	0.38	0.0006
	2 vs 3	0.0309	0.19	0.13	0.17
	1 vs 3	<0.0001	0.0124	0.0064	0.0060

P values for comparison of changes in total iron (mg/interval) in those taking and not taking iron; p values are based on t tests

Time Since Donation	interval	<26 ng/mL	>26 ng/mL
0 to 8 weeks	1	<0.0001	<0.0001
8 to 16 weeks	2	0.19	0.79
16 to24 weeks	3	0.81	0.98