Reducing the variation in performance of antibody titrations

Area of Science:

• Transfusion Medicine
• Immunology
• Clinical Laboratory Science

Background:

• Antibody titration lacks standardized procedures, leading to inconsistent results.
• Interlaboratory variation in antibody titers poses challenges in clinical settings.

Purpose of the Study:

• To evaluate if a detailed, uniform antibody titration procedure reduces interlaboratory variation.
• To compare the efficacy of tube-based and gel card methods in standardization.

Main Methods:

• Thirty-five laboratories performed antibody titrations using routine and a uniform method.
• The uniform method involved titrating against specified red cell phenotypes and using 1+ and w+ endpoints.
• Paired analyses of variance were conducted to assess variability.

Main Results:

• A uniform method with a 1+ endpoint did not significantly reduce variance.
• A statistically significant reduction in variance for anti-D and anti-A titers was observed with the uniform method using a w+ endpoint in tube-based assays at the antiglobulin (AHG) phase.
• Gel card testing with a w+ endpoint was not sufficiently analyzed due to limited reporting.

Conclusions:

• A detailed, uniform tube-based antibody titration method, read at the antiglobulin (AHG) phase with a w+ endpoint, effectively reduces interlaboratory variability.
• Standardization of antibody titration protocols is essential for improving accuracy and consistency in clinical diagnostics.