TABLE 4.

Summary of forest plot analyses of the effect of zinc supplementation in infants and children aged ≤3 y on anemia (OR), analyzed by duration, chemical formula, and comparator group¹

Group/subgroup	References	Mean difference	95% CI	P	I 2
Children receiving interventions for <3 mo by zinc dose
<5 mg/d	(48)	4.33	0.14, 132.32		NA
5–10 mg/d	(48, 73)	1.74	1.01, 2.98		0
Overall		1.78	1.04, 3.03	0.03	0
Children receiving interventions for >3 mo by zinc dose
<5 mg/d	(19, 34)	0.85	0.37, 1.95		44
5–10 mg/d	(12, 29, 36–39, 43, 47, 53–55, 70, 71)	1.08	0.93, 1.25		30
10.1–20 mg/d	(54)	1.07	0.60, 1.90		NA
Overall		1.06	0.92, 1.22	0.43	28
Children receiving zinc through zinc gluconate by zinc dose
5–10 mg/d	(37, 38, 55, 73)	1.10	0.71, 1.72		41
Overall		1.10	0.71, 1.72	0.66	41
Children receiving zinc through zinc sulfate by zinc dose
<5 mg/d	(34, 48)	0.66	0.36, 0.121		0
5–10 mg/d	(12, 29, 39, 47, 48, 71)	1.28	0.98, 1.67		49
Overall		1.18	0.92, 1.53	0.19	47
Children receiving zinc through an unstated approach by zinc dose
5–10 mg/d	(36, 43, 53, 70)	0.97	0.81, 1.15		0
10.1–20 mg/d	(54)	1.07	0.60, 1.90		NA
Overall		0.97	0.82, 1.15	0.76	0
Children receiving zinc vs. placebo by zinc dose
<5 mg/d	(19)	3.75	0.65, 21.74		NA
5–10 mg/d	(29, 36, 39, 43, 47, 53, 55, 70, 71)	0.89	0.75, 1.05		0
Overall		0.90	0.76, 1.06	0.21	0
Children receiving low compared with high dose zinc
5–10 mg/d	(43, 48)	1.13	0.83, 1.53		0
Overall		1.13	0.83, 1.53	0.44	0

¹NA, not applicable.