| Methods |
Randomized controlled trial (RCT) |
| Participants |
303 HIV‐positive pregnant women from metropolitan Bloemfontein, South Africa. Most participants (56%) lived in informal settlements and all attended public health facilities. For the trial, women were asked to volunteer for HIV testing during their first antenatal visit. Pretest counselling was done in groups, and post‐test counselling was done individually. Women who were seropositive for HIV were asked to participate in the trial. |
| Interventions |
Vitamin A supplementation versus placebo |
| Outcomes |
Mother‐to‐child transmission (MTCT) of HIV |
| Notes |
All trial participants gave separate informed consent for the trial. All patients were recruited by one study physician and received verbal or written information (Sesotho, English, or Afrikaans information sheets). |
| Risk of bias |
| Bias |
Authors' judgement |
Support for judgement |
| Random sequence generation (selection bias) |
Unclear risk |
The trial authors did not mention the method used to generate the randomization sequence. |
| Allocation concealment (selection bias) |
Unclear risk |
The trial authors did not describe the method used to conceal the treatment allocation. |
| Blinding (performance bias and detection bias)
All outcomes |
Low risk |
The trial used an identical placebo; HIV diagnosis was done in the laboratory. |
| Incomplete outcome data (attrition bias)
All outcomes |
High risk |
More than 48% of women were lost to follow‐up and we do not know whether this was related to outcomes. |
| Selective reporting (reporting bias) |
High risk |
Not all prespecified outcomes were reported in various publications from this trial. |
| Other bias |
Low risk |
We do not believe that other biases were introduced, over and above the high loss to follow‐up and the selective reporting. |
