Outcome or Subgroup

Studies

Participants

Statistical Method

Effect Estimate

3.1 Haemoglobin Concentrations

8

2551

Mean Difference (IV, Random, 95% CI)

0.22 [0.01, 0.43]

3.1.1 Snack Group

6

1991

Mean Difference (IV, Random, 95% CI)

0.17 [-0.05, 0.38]

3.1.2 Lunch Group

2

560

Mean Difference (IV, Random, 95% CI)

0.53 [0.20, 0.87]

3.2 Serum Ferritin Concentration

6

1627

Mean Difference (IV, Random, 95% CI)

7.43 [0.02, 14.84]

3.2.1 Snack Group

4

1106

Mean Difference (IV, Random, 95% CI)

8.12 [-3.64, 19.89]

3.2.2 Lunch Group

2

521

Mean Difference (IV, Random, 95% CI)

7.80 [-1.74, 17.33]

3.3 Iron Intake

9

1187

Mean Difference (IV, Random, 95% CI)

1.88 [0.95, 2.81]

3.3.1 Snack Group

3

333

Mean Difference (IV, Random, 95% CI)

4.70 [0.30, 9.11]

3.3.2 Lunch Group

6

854

Mean Difference (IV, Random, 95% CI)

0.31 [-0.17, 0.79]