Vitamin A status in preschool-age Indonesian children as assessed by the modified relative-dose-response assay.
 The modified relative-dose-response (MRDR) assay has been validated in rats as a function of vitamin A status and tested in a group of American children.
 In this study the MRDR assay was applied to West Javan children who are at risk of being vitamin A deficient.
 Of 86 children enrolled, 75 were tested.
 In a time-course study involving 22 children aged 3.7-5.3 y, blood samples were taken at different times after doses of 0.35 mumol 3,4-didehydroretinyl acetate/kg body wt.
 Generally, the ratio of dehydroretinol to retinol (DR-R ratio) peaked between 4 and 8 h.
 Thereafter, in a survey of 53 children aged 0.6-4.8 y, single blood samples were drawn 5 h after the dehydroretinyl acetate dose.
 The DR-R ratio ranged from 0.0028 to 0.169.
 With a DR-R ratio of 0.03 as the cutoff value, 62% of the children were judged to be of marginal vitamin A status.
