Indirect Comparison of the MassTrak Reagent Kit for LC/MS/MS Analysis of Whole Blood Tacrolimus with Three Established Immunoassays
In routine clinical laboratories it is not practical to maintain multiple assays for the same analyte for logistic and financial reasons, making it difficult to perform long-term method comparison studies when new analytical tests are introduced. We have used external quality assurance (EQA) returns as an indirect means to compare the MassTrak™ LC/MS/MS whole blood tacrolimus assay with established immunoassays. For some of the assays, there are a large number of test centres contributing data so that the method mean provides a reliable measure of the accuracy of that technique. Furthermore, the same sample set may be used for all the comparisons and long-term comparative assay performance inferences can be made.