Table 3. Sensitivity Analyses Examining Higher Thresholds to Define Iron and Vitamin A Sufficiency on Pooled Hemoglobin Fifth Percentile Estimates for Healthy Individualsa.
| Inclusion criteria | Analytical sample, participants, No. (% of original No.) | Hemoglobin fifth percentile (95% CI), g/dLb |
|---|---|---|
| Preschool children (original N = 33 699) | ||
| No inflammation, no VAD (threshold 1), no malaria, and ferritin ≥12 ng/mL (22 surveys) | 13 445 (39.9) | 9.65 (9.26-10.04) |
| No inflammation, no VAD (threshold 2), no malaria, and ferritin ≥20 ng/mL (18 surveys) | 6752 (20.0) | 9.75 (9.29-10.21) |
| No inflammation, no VAD (threshold 2), no malaria, and ferritin ≥30 ng/mL (16 surveys) | 4041 (11.9) | 9.83 (9.34-10.32) |
| Nonpregnant women of reproductive age (original N = 46 251) | ||
| No inflammation, no VAD (threshold 1), no malaria, and ferritin ≥15 ng/mL (22 surveys) | 25 880 (56.0) | 10.81 (10.35-11.27) |
| No inflammation, no VAD (threshold 2), no malaria, and ferritin ≥30 ng/mL (22 surveys) | 16 285 (35.2) | 11.02 (10.59-11.45) |
| No inflammation, no VAD (threshold 2), no malaria, and ferritin ≥50 ng/mL (22 surveys) | 9030 (19.5) | 11.03 (10.58-11.49) |
| No inflammation, no VAD (threshold 2), no malaria, and ferritin ≥100 ng/mL (12 surveys) | 2957 (6.3) | 11.02 (10.34-11.70) |
Abbreviation: VAD, vitamin A deficiency.
SI conversion factor: To convert ferritin to micrograms per liter, multiply by 1.0; hemoglobin to grams per liter, multiply by 10.
a
VAD is defined as retinol-binding protein or retinol greater than or equal to 20.1 μg/dL (threshold 1) or greater than or equal to 3.01 μg/dL (threshold 2) (to convert to micromoles per liter, multiply by 0.0349).
b
Estimates are not statistically significant at α = .05 within each target population.