Table 1. Characteristics of studies contributing and not contributing data to the main network meta-analysis.
| Characteristic | Contributed data to the main NMA | Did not contribute data to the main NMA |
|---|---|---|
| Number of studies | 30 | 23 |
| Total number of women * | 3,243 | 4,854 |
| Publication year (median, min-max) | 2014 (1969, 2020) | 2005 (1978, 2020) |
| Country income group n (%) | ||
| Low and middle-income countries | 22 (73) | 14 (61) |
| Upper-middle and high income countries | 8 (27) | 9 (39) |
| Total number of arms | 62 | 47 ** |
| Anaemia status at baseline *** | ||
| Mild (109-100 g/L) | 11 | 15 |
| Moderate (99-70 g/L) | 44 | 23 |
| Severe (69-40 g/L) | 5 | 3 |
| Not reported | 2 | 6 |
| Number of unique interventions | 15 | 13 |
| Total number of unique comparisons | 19 | 15 |
| Comparisons | ||
| ferrous asparto glycinate vs ferrous ascorbate | 1 | |
| Carbonyl iron vs ferrous fumarate | 1 | |
| iron polymaltose complex vs ferrous fumarate | 1 | |
| Iron chondroitinsulfuric acid complex vs ferrous sulphate | 1 | |
| Iron amino acid chelate vs ferrous sulphate | 1 | |
| ferrous gluconate vs ferrous sulphate | 1 | |
| iron polymaltose complex vs ferrous sulphate | 1 | |
| NaFeEDTA vs ferrous sulphate | 1 | |
| lactoferrin vs ferrous sulphate | 4 | 1 |
| ferrous sulphate vs “no-iron intervention” | 1 | 8 |
| IFB vs “no-iron intervention” | 1 | |
| ferrous gluconate vs “no-iron intervention” | 1 | |
| NaFeEDTA vs “no-iron intervention” | 1 | |
| IV iron dextran vs “no-iron intervention” | 1 | |
| ferrous sulphate vs ferrous sulphate and IV Iron polymaltose complex | 1 | |
| ferrous sulphate vs IV iron sucrose | 7 | 3 |
| ferrous fumarate vs IV iron sucrose | 4 | |
| ferrous ascorbate vs IV iron sucrose | 2 | |
| iron polymaltose complex vs IV iron sucrose | 1 | |
| ferrous sulphate vs IV iron dextran | 1 | |
| ferrous gluconate vs IV iron dextran | 1 | |
| ferrous fumarate vs IV iron dextran | 1 | |
| lactoferrin vs IV iron dextran | 1 | |
| ferrous fumarate vs IV iron polymaltose complex | 1 | |
| ferrous sulphate vs IV ferric carboxymaltose | 1 | |
| IV iron sucrose vs IV ferric carboxymaltose | 2 | |
| IV iron sucrose vs IV iron dextran | 1 | 2 |
| ferrous sulphate vs IM iron dextran | 2 | |
| ferrous sulphate vs IM iron sorbitol citric acid | 1 | |
| IV iron sucrose vs IM iron sorbitol citric acid | 3 | |
NMA, network meta-analysis; IV, intravenous; IM, intramuscular
*
The number of women analysed in eligible arms
**
Arms in two originally 3-arm studies with iron and iron and vitamins vs placebo (Sun 2010, Ma 2010) were combined into one
***
Values correspond to number of arms not studies