2-STAGE PROCEDURE FOR EVALUATING INTERASSAY CARRYOVER ON RANDOM-ACCESS INSTRUMENTS

A two-stage statistical procedure based on Dunnett's multiple comparis on procedures with a control has been developed for detecting interass ay carryover biases on the Abbott AxSYM(TM) System, a random- and cont inuous-access immunoanalyzer. With this procedure, every potential sou rce of interassay carryover can be tested and estimated, In minimizing required sample sizes, the first stage is used primarily to detect an d eliminate from further testing the assay reagent sources that do not cause carryover biases and the assay sources that cause very large ca rryover biases. Retested more extensively in the second testing stage are the cases where the data from the first testing stage are insuffic ient for judgment. An example data set from the Abbott AxSYM Free T-4 assay is used to illustrate the methodology.