Reducing the variation in performance of antibody titrations

Area of Science:

• Transfusion Medicine
• Immunology
• Clinical Laboratory Science

Background:

• Antibody titration lacks standardized methods, leading to variability in results.
• This study addresses the need for a uniform procedure to improve consistency in antibody titre measurements.

Purpose of the Study:

• To investigate if a detailed, uniform antibody titration procedure reduces interlaboratory variation.
• To compare results from routine methods versus a standardized method using both tube-based and gel card techniques.

Main Methods:

• 35 laboratories performed antibody titrations using routine methods and a uniform method.
• The uniform method involved titrating serum against specified red cell phenotypes and using 1+ and weak-positive (w+) end-points.
• Paired analyses of variance were used to compare results.

Main Results:

• The uniform method with a 1+ end-point did not significantly reduce variance.
• A statistically significant reduction in variance for anti-D and anti-A titres was observed with the uniform method and a w+ end-point in tube-based testing at the antiglobulin phase.
• Gel card testing analysis was limited due to insufficient w+ end-point results.

Conclusions:

• A detailed, uniform antibody titration method, particularly tube-based with a w+ end-point at the antiglobulin phase, effectively reduces interlaboratory variability.
• Standardization of antibody titration procedures is essential for reliable clinical laboratory results.