TABLE 5.
Summary of forest plot analyses of the effect of zinc supplementation in infants and children aged ≤3 y on serum ferritin (μg/L), 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) | −3.00 | −22.84, 16.84 | NA | |
| 5–10 mg/d | (48) | −3.79 | −16.21, 8.63 | 0 | |
| 10.1–20 mg/d | (51) | −0.10 | −3.85, 3.65 | NA | |
| Overall | −0.49 | −4.02, 3.04 | 0.79 | 0 | |
| Children receiving interventions for >3 mo by zinc dose | |||||
| <5 mg/d | (19, 34) | −1.85 | −9.37, 5.67 | 0 | |
| 5–10 mg/d | (12, 26, 29, 31, 35, 39, 40, 47, 70–72, 74, 75) | −2.32 | −5.18, −0.53 | 99 | |
| 10.1–20 mg/d | (59) | −3.23 | −8.40, 1.94 | 0 | |
| Zn bolus | (18, 28) | 3.09 | −2.25, 8.43 | 0 | |
| Overall | −1.80 | −4.31, −0.72 | 0.16 | 98 | |
| Children receiving zinc through zinc gluconate by zinc dose | |||||
| Zn bolus2 | (18) | 1.30 | −5.84, 8 | NA | |
| Overall | 1.30 | −5.84, 8 | 0.72 | NA | |
| Children receiving zinc through zinc sulfate by zinc dose | |||||
| <5 mg/d | (34, 48) | −4.11 | −11.95, 3.73 | 0 | |
| 5–10 mg/d | (12, 26, 29, 35, 39, 40, 47, 48, 71, 72, 75) | −2.50 | −6.69, 1.70 | 99 | |
| 10.1–20 mg/d | (51) | −0.10 | −3.85, 3.65 | NA | |
| Overall | −2.48 | −6.30, 1.34 | 0.20 | 99 | |
| Children receiving zinc through zinc acetate by zinc dose | |||||
| 10.1–20 mg/d | (28) | 5.35 | −2.68, 13.39 | 0 | |
| Overall | 5.35 | −2.68, 13.39 | 0.19 | 0 | |
| Children receiving zinc through an unstated approach by zinc dose | |||||
| 5–10 mg/d | (31, 70, 74) | −0.93 | −2.46, 0.61 | 78 | |
| Overall | −0.93 | −2.46, 0.61 | 0.24 | 78 | |
| Children receiving zinc through an “other” approach by zinc dose | |||||
| <5 mg/d | (19) | 6.65 | −9.21, 22.51 | NA | |
| 10.1–20 mg/d | (59) | −3.23 | −8.40, 1.94 | 0 | |
| Overall | −2.28 | −7.19, 2.63 | 0.36 | 0 | |
| Children receiving zinc vs. placebo by zinc dose | |||||
| <5 mg/d | (19) | 6.65 | −9.21, 22.51 | NA | |
| 5–10 mg/d | (12, 29, 39, 40, 47, 70–72, 74, 75) | −0.56 | −2.35, 1.23 | 90 | |
| 10.1–20 mg/d | (59) | −3.20 | −9.33, 2.93 | NA | |
| Zn bolus2 | (18, 28) | 2.75 | −3.30, 8.79 | 0 | |
| Overall | −0.41 | −2.08, 1.25 | 0.63 | 86 | |
| Children receiving low- compared with high-dose zinc | |||||
| 5–10 mg/d | (48, 74) | −8.10 | −18.98, 2.78 | 45 | |
| Overall | −8.10 | −18.98, 2.78 | 0.14 | 45 | |