Validation of a rapid enzyme immunoassay for the quantitation of retinol-binding protein to assess vitamin A status within populations.

Objective: To compare the prevalence of vitamin A deficiency (VAD) among Cambodian preschool children as determined by the retinol-binding protein-enzyme immunoassay (RBP-EIA) and direct measurement of serum retinol by high-performance liquid chromatography (HPLC).

Setting And Subjects: Sera from 359 children were randomly selected from archived specimens collected in a national VAD prevalence survey in Cambodia.

Methods: Sera were first analyzed for retinol content by HPLC and then subjected to analysis using RBP-EIA to determine serum RBP concentrations.