Le Huong 2007

Methods	RCT Length of follow‐up: 6 months
Participants	All children living in endemic area (children screened for anaemia then randomized and all children treated) Number analysed for primary outcome: 510 randomized Mean age: ˜7.3 years Inclusion criteria: children in Grades 1 to 3 with haemoglobin < 110 g/L but not < 70 g/L Exclusion criteria: haemoglobin concentrations < 70 g/L
Interventions	Multiple dose vs placebo Factorial design Mebendazole 500 mg at 0 and 3 months Iron‐fortified noodles and mebendazole 500 mg; Noodles without iron fortificant and mebendazole 500 mg; Iron‐fortified noodles and placebo; Noodles without iron fortificant and placebo; and Iron supplementation and mebendazole 500 mg.
Outcomes	Haemoglobin ‐ change; Prevalence of underweight, stunting and wasting  (defined as ‐2SD for weight‐for‐height, height‐for‐age and weight‐for‐ age using WHO/NCHS reference data). Not included in review: Ferritin; serum transferrin; worm prevalence; CRP.
Notes	Location: Vietnam Community category: 2 Source of funding: Neys‐van Hoogstraten Foundation, Ellison Medical Foundation and the Ministry of Education and Training, Vietnam.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Randomized, no further details.
Allocation concealment (selection bias)	Low risk	Central allocation. "Randomization was carried out by a researcher [...] who did not know the children and could not introduce bias in the randomization".
Blinding (performance bias and detection bias) All outcomes	Low risk	Participants and key personnel blinded. "Children, teachers and researchers were blinded to the treatment". Placebo identical to intervention drug.
Incomplete outcome data (attrition bias) All outcomes	Low risk	409/425 participants were evaluated. Reason for drop‐out: refusal (n = 16, intervention: 4.7%, placebo: 2.3%). Inclusion of all randomized participants (number evaluable/number randomized): 96% (409/425).
Selective reporting (reporting bias)	Low risk	Pre‐specfied outcomes reported.
Other bias	Low risk	No obvious other sources of bias.