[Multisite-based approach to assure inter-assay system compatibility among different exclusive-typed immunoassay...

Area of Science:

• Clinical Chemistry
• Immunoassay Technology
• Biochemical Standardization

Context:

• Exclusive immunoassay systems offer high precision but lack inter-system compatibility.
• This incompatibility complicates patient transfers and laboratory system changes.
• Differences in calibrator composition, including human serum vs. non-human albumin solutions, contribute to variability.

Purpose:

• To investigate methods for assuring inter-immunoassay compatibility across different systems.
• To evaluate the effectiveness of using exchanged calibrators for compatibility adjustments.
• To identify key factors hindering reliable comparison of immunoassay results.

Summary:

• Determinations of total protein, albumin, and electrophoretic fractionation revealed significant differences in calibrator protein constituents among four immunoassay systems.
• Regression analysis showed slopes close to 1.0 for alpha-fetoprotein and prostate-specific antigen, but wide dissociation (0.28-4.71) for CA19-9.
• Converting clinical serum sample results using linear regression based on exchanged calibrators failed to improve compatibility, with varied effects across systems and parameters.

Impact:

• Simple conversion methods using exchanged calibrators and linear regression are insufficient for achieving reliable inter-immunoassay compatibility.
• Standardization of target molecules, probes, and calibrator constituents is urgently needed.
• Lack of standardization hinders accurate and consistent diagnostic testing across different healthcare settings.