Kumwenda 2002.

Methods	RCT. Participants were assigned to treatment using computer‐generated random numbers, and treatment was concealed by pre‐packing study supplements in sequentially numbered series assigned to study identification numbers. Sixty‐three women (9%) were lost to follow‐up before delivery and excluded from the analyses. The 14 pairs of twins in the study were excluded from the birth weight and mortality analyses because twins are known to have lower birth weights and higher mortality rates.
Participants	697 pregnant HIV‐positive women enrolled at 18 to 28 week's gestation in Blantyre, Malawi. The prevalence of vitamin A deficiency (< 0.70 µmol/L) was 51% during the second trimester.
Interventions	All women received orally administered daily doses of iron (30 mg of elemental iron) and folate (400 µg) from enrolment until delivery. One‐half of the women were randomized to receive daily doses of orally administered vitamin A (10,000 IU).
Outcomes	Stillbirths, HIV infection in child, preterm delivery, low birthweight, postpartum CD4 levels.
Notes	All women received oral vitamin A (100,000 IU) at 6 weeks postpartum, as per policy of the Malawi Ministry of Health.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	The trial authors determined treatment assignment by use of a computer random‐number generator.
Allocation concealment (selection bias)	Low risk	Treatment assignment was concealed by pre‐packing study supplements in sequentially numbered series assigned to study identification numbers. Mothers were assigned an original study identification number at enrolment and were given the next sequentially numbered opaque bottle with supplements.
Blinding (performance bias and detection bias) All outcomes	Low risk	Supplements containing vitamin A, iron, and folate were identical in appearance to the supplements containing iron and folate.
Incomplete outcome data (attrition bias) All outcomes	Low risk	Nine per cent of women were lost to follow‐up and we do not believe that this was related to the outcome. We do not believe this introduced bias.
Selective reporting (reporting bias)	Low risk	The trial authors reported on all outcomes specified in the goals of the study articles.
Other bias	Low risk	We do not believe that other biases were introduced that could have affected the study findings.

Abbreviations: ART: antiretroviral therapy; MTCT: mother‐to‐child transmission; RCT: randomized controlled trial.