Italian external quality assessment scheme in immunoassay

Area of Science:

• Clinical Chemistry
• Laboratory Medicine
• Quality Assurance

Background:

• External Quality Assessment (EQA) schemes are crucial for monitoring laboratory performance.
• Italian EQA programs assess a wide range of analytes, including hormones, tumor markers, and hepatitis B markers.

Purpose of the Study:

• To report the organization, data processing, and results of Italian EQA schemes for specific biomarkers.
• To evaluate laboratory performance and identify trends in analytical variability over time.

Main Methods:

• Organization of EQA schemes involving approximately 250 laboratories for hormones/tumor markers and 200 for hepatitis B markers.
• Collection and statistical analysis of laboratory results to generate periodic and end-of-period reports.
• Assessment of imprecision and average bias for laboratories and kits.

Main Results:

• Significant improvements in laboratory variability observed for TSH, progesterone, estradiol, testosterone, CEA, and ferritin from 1980-1988.
• Slight improvements noted for cortisol, FSH, prolactin, and AFP; no improvement for total T3 and T4.
• High variability in LH results attributed to differences in monoclonal antibody-based kits.

Conclusions:

• EQA schemes effectively track laboratory performance and analytical variability.
• Specific analytes show marked improvement, while others require further attention or method standardization.
• Kit-specific differences can significantly impact inter-laboratory variability for certain markers.