Fig 1.
Flow diagram of search results and study selection.
Fig 2.
Risk of bias in included studies.
Fig 3.
Summary of findings.
Fig 4.
(A). Comparison of vitamin A supplementation versus control. Outcome 1: neonatal death (death before 1 month). (B). Comparison of vitamin A supplementation versus control. Outcome 2: bronchopulmonary dysplasia (oxygen use at 28 days in survivors) (C). Comparison of vitamin A supplementation versus control. Outcome 3: bronchopulmonary dysplasia at 36 weeks’ postmenstrual age in survivors (D). Comparison of vitamin A supplementation versus control. Outcome 4: length of hospital stays.