Error Rate, Precision, and Accuracy in Immunohematology

Abstract

Quality control in the blood bank was traditionally concentrated in the areas of reagents, equipment and components. This paper shows that it can be extended to the measurement of error rate, accuracy and reproducibility as well. A "correction rate" should be used as a correlate of actual error rate, since numbers of errors in final [human] ABO interpretations are infrequent and difficult to accumulate. Accuracy is measured as the frequency of false positive and false negative results, using weakly active antibodies in the test situation and in actual practice. Reproducibility can be measured with a series of coded duplicate samples covering the range of immunohematologic reactivity. By using these methods, a laboratory can regularly measure error rate, accuracy and reproducibility as part of its quality control program.