A comprehensive evaluation of the proficiency testing program for the HIV-1 BED incidence assay

Area of Science:

• * Clinical diagnostics and epidemiology
• * Biomarker assay validation and quality control

Background:

• * The HIV-1 BED incidence assay, developed by the CDC, has been commercially available for HIV-1 incidence surveillance since 2005.
• * A dedicated proficiency testing (PT) program was established in 2006 to ensure consistent and accurate performance across participating laboratories.

Purpose of the Study:

• * To evaluate the performance and reproducibility of the HIV-1 BED incidence assay across multiple laboratories through a structured PT program.
• * To identify common sources of error and areas for improvement in BED assay implementation for HIV surveillance.

Main Methods:

• * Implementation of a BED-specific proficiency testing program involving a panel of eight coded specimens.
• * Monitoring of laboratory performance through analysis of reported results, optical density values, and reproducibility statistics over seven PT rounds.
• * Tracking of inter-laboratory agreement, specimen handling, and reagent quality control.

Main Results:

• * High success rate, with 96.1% of laboratories reporting results and 95.4% achieving a perfect score.
• * Excellent correlation between observed and expected normalized optical density (OD-n) values (R² = 0.98).
• * Demonstrated high reproducibility with 99.3% agreement in classification and minimal deviation (1.8%) for duplicate specimens.

Conclusions:

• * The BED-specific PT program successfully monitored laboratory performance, confirming the assay's high accuracy and reproducibility for HIV-1 incidence surveillance.
• * Identified common errors including transcriptional mistakes, reagent issues, and specimen handling, guiding targeted improvements.
• * The PT program serves as a valuable model for future quality assurance initiatives for emerging HIV incidence assays.