Analysis of sample‐to‐cutoff ratios on chemiluminescent immunoassays used for blood donor screening highlights the need for serologic confirmatory testing

Abstract

Although high s/co ratios were predictive of confirmed-positive results in all four assays, a number of confirmed-positive samples gave low values while some biologic false-positive samples showed high values. As the s/co ratio distributions for BFR and confirmed-positive results overlapped for all four PRISM assays, this study highlights the importance of serologic confirmatory testing and the need for caution when using screening IA results to assign a final donor status.