[Cause and countermeasure for appearance of false positivity or false negativity in enzyme immunoassay (EIA)]

The appearance of false positivity or false negativity in EIA (enzyme immunoassay) brings often trouble of judgment for diagnosis or monitoring of disease. Most of the appearance can be found out by the dilution test of test sample or the recovery test by addition of standard antigen to test sample. It was pointed out that the assay conditions, the assay method, the dose of enzyme-labeled antibody and the enzyme employed in EIA system might affect the appearance, and the autoantibody to antibody employed in the system, the enzyme and the antibody of idiotype in test sample might become factors of the appearance. Furthermore, the countermeasure for the appearance was concretely described in the paper.