Suharno 1993.

Methods	Double‐blinded RCT.
Participants	Inclusion criteria: middle and low socioeconomic; 16‐24 weeks pregnant; 17‐35 years old; parity 0‐4; Hb 80‐109 g/L.
Interventions	Intervention group 1: 63 women received vitamin A (2.4 mg retinol as retinyl palmitate) (equivalent to 8000 IU of vitamin A) and placebo iron tablets daily for 8 weeks. Intervention group 2: 63 women received iron tablets (60 mg ferrous sulphate) and placebo vitamin A daily for 8 weeks. Intervention group 3: 63 women received vitamin A and iron daily for 8 weeks. Control group: 62 women received both placebo daily for 8 weeks.
Outcomes	Maternal anaemia indices.
Notes	Vitamin A levels were measured before starting supplementation. Country: Indonesia. Study setting: rural villages in 3 subdistricts of Bogo, West Java.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	"randomly."
Allocation concealment (selection bias)	Low risk	'An independent researcher randomly labelled' the preparations.
Blinding of participants and personnel (performance bias) All outcomes	Low risk	Participants and personnel "Double blind".
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	No information given.
Incomplete outcome data (attrition bias) All outcomes	Low risk	54 (17%) women were excluded from the analysis: 11 moved, 23 taken supplement less than 8 weeks, 10 refused blood sample, 10 not available for 2nd blood sample.
Selective reporting (reporting bias)	Unclear risk	The protocol of the study is not available at the moment.
Other bias	Low risk	No other bias awarded.