Ma 2010.

Methods	RCT with 4 arms including a placebo and individual randomisation.
Participants	164 anaemic pregnant women (80 g/L, Hb, 110 g/L), 12–24 weeks' gestation and 20–35 years old recruited between March 2004 and September 2006 from the community hospitals of Shen County in the central area of China.
Interventions	Participants were randomly allocated to 1 of 4 groups for this 2‐month intervention in the order of recruitment: group 1 (n = 41) received placebo; group 2 (n = 41) received 60 mg elemental iron (as ferrous sulphate); group 3 (n = 41) received 60 mg elemental iron (as ferrous sulphate) and 400 μg (0.4 mg) folic acid daily; group 4 (n = 41) received 60 mg elemental iron (as ferrous sulphate), and 400 μg (0.4 mg) folic acid, 2 mg retinol and 1 mg riboflavin daily. Setting and health worker cadre: In each community, a local female community health worker called ‘village nurse’ was responsible for the recruitment and distribution of the supplements. Women were recruited from the community hospitals and then home‐visited once a week by the village nurse to replenish supplements and to monitor compliance by counting and recording the number of supplements that were taken. The nurse also provided counselling about the possible side effects.
Outcomes	Hb, plasma iron, ferritin, folic acid, retinol riboflavin after the 2 months intervention. Other outcomes included membrane fluidity, oxidative stress markers such as GSH‐Px, SOD, and MDA.
Notes	This study is included but does not provide any data that can be useful for purposes of this review. Gestational age at start of supplementation: unspecified or mixed gestational ages at the start of supplementation. Anaemic status at start of supplementation: anaemic. Daily iron dose: high daily dose (60 mg or more mg iron daily). Iron release formulation: normal. Iron compound: ferrous sulphate. Malaria setting: yes. Malaria as of 2011: Malaria risk, including P. falciparum malaria, exists in Yunnan and to a lesser extent in Hainan. P. falciparum resistance to chloroquine and sulphadoxine–pyrimethamine reported. Limited risk of P. vivax malaria exists in southern and some central provinces, including Anhui, Ghuizhou, Henan, Hubei, Jiangsu. There is no malaria risk in urban areas.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	High risk	Quasi‐randomised as participants were randomly allocated to 1 of 4 groups for this 2‐month intervention in the order of recruitment: group.
Allocation concealment (selection bias)	Unclear risk	Tretaments were colour coded. It was stated that the code was not revealed until after the analysis.
Blinding of participants and personnel (performance bias) All outcomes	Low risk	This was a placebo‐controlled trial. It was stated that women and staff were blind to treatment.
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Low risk for laboratory outcomes.
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	164 women were randomised and 145 (88%) were included in the analysis.
Selective reporting (reporting bias)	Unclear risk	There is insufficient information to permit judgement.
Other bias	Low risk	No other bias apparent.