Nga 2009

Methods	RCT Length of follow‐up: 4 months
Participants	All children living in endemic area Number analysed for primary outcome: 510 randomized Age range: 6 to 8 years Inclusion criteria: school children aged 6 to 8 years and written informed consent from parents/caregivers Exclusion criteria: haemoglobin concentrations < 80 g/L, chronic illness, congenital abnormalities, mental or severe physical handicap, severe malnutrition ([z‐scores for weight‐for‐height (WHZ) < ‐3.0 SD), obesity (BMI ≥ 25 or z‐scores for WHZ > +2 SD), or receiving deworming within the previous 6 months
Interventions	Single dose vs placebo Non‐fortified biscuit plus placebo deworming‐treatment (placebo); Multi‐micronutrient–fortified biscuit plus placebo deworming‐treatment; Non‐ fortified biscuit plus deworming treatment with albendazole (400 mg); Multi‐micronutrient–fortified biscuits plus deworming treatment with Albendazole (400 mg).
Outcomes	Haemoglobin; Mean MUAC; Cognitive function; Change in weight‐for‐age (WAZ), height‐for‐age (HAZ), and WHZ, using the EpiInfo program (version 6.0, CDC) and the National Center for Health Statistics/WHO nutritional reference data. Not included in review: changes in zinc, iodine, and ferritin concentration; worm prevalence Measured but not reported: weight and height recorded at baseline and end point but only baseline data reported. Skin fold thickness recorded at baseline and end point, but no data reported.
Notes	Location: Vietnam Community category: 2 This trial was supported by the Neys‐van Hoogstraten Foundation, The Netherlands, and the Ellison Medical Foundation.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Computer generated. "pupils were allocated to 1 of the 4 intervention groups based on a computer generated list, matched on age (12‐mo age groups) and sex, and using a block size of 8 by one of the researchers not involved in the field work".
Allocation concealment (selection bias)	Low risk	Central allocation.
Blinding (performance bias and detection bias) All outcomes	Low risk	Participants and key personnel were blinded. "All investigators, field assistants, teachers, and children did not know the codes of the trial groups". Placebo identical to treatment (orange chewable tablet).
Incomplete outcome data (attrition bias) All outcomes	Low risk	482/510 randomized participants were evaluated. Reasons for drop‐out: moved (n =12), surgery (n = 2), refusal to participate (n = 14), balanced across intervention groups. Inclusion of all randomized participants (number evaluable/number randomized): 94.5% (482/510).
Selective reporting (reporting bias)	High risk	Three outcomes (weight, height and skin fold thickness) not reported adequately.
Other bias	Low risk	No obvious other source of bias.