['Preterm infants show reduced retinal sensitivity at term corrected age compared with newborn term infants. We tested the hypothesis that retinal sensitivity in preterm infants is improved by early, high-dose vitamin A.', "We report a double-blind, randomized controlled trial of infants <32 weeks' gestation and/or <1501 g birth weight. Supplemented infants received additional intramuscular vitamin A 10\xa0000 IU 3 times weekly from day 2 for a minimum of 2 weeks or until establishment of oral feeding. Hepatic stores were assessed by relative dose response (RDR). The primary outcome measure was cone-corrected dark-adapted retinal rod sensitivity measured by electroretinogram at 36 weeks' postmenstrual age (PMA).", "Eighty-nine infants (42 supplemented and 47 controls) were recruited. Plasma retinol was higher in supplemented infants at 7 and 28 days (median, 1.0 vs 0.5 μmol/L and 0.7 vs 0.6 μmol/L; P < .001 and .03, respectively). Neither plasma retinol nor RDR differed between groups at 36 weeks' PMA. Retinal sensitivity was greater in supplemented infants (-0.81 vs -0.61 log cd • s • m(-2); P < .03) and was not related to RDR."] Does vitamin A supplementation improve retinal function in infants at risk of retinopathy of prematurity?