Interpreting results of immunoassay-based methods frequently presents a challenge for physicians, especially when caring for patients at multiple institutions that use different assay platforms. For many analytes including tumor markers, endocrine hormones, and cardiac biomarkers, results generated on different platforms are not directly comparable. This is due to the absence of a universally accepted reference material, which manufacturers need to calibrate their assays to a common standard.
Instead, test results must be interpreted using assay-specific reference intervals—a concept that comes naturally to clinical laboratorians but often is foreign to many physicians and patients. This lack of uniform results causes confusion that can adversely affect patient care, particularly when patients are diagnosed at one hospital but pursue follow-up care elsewhere. For example, does an increased CA-125 value at follow-up at a different institution reflect disease progression or simply differences in assay calibration? A lack of standardization also makes it impossible to transfer diagnostic cutoffs from one institution to another unless the assay platforms are identical.
Given the confusion associated with non-standardized assays, why haven’t all immunoassays already been standardized?
Source: alfa
