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

J Clin Microbiol. 2011 Oct;49(10):3470-3. doi: 10.1128/JCM.01122-11. Epub 2011 Aug 10.

Abstract

The HIV-1 BED incidence assay was developed at the Centers for Disease Control and Prevention and since 2005 has been available as a commercial kit for use in HIV-1 incidence surveillance. A BED-specific proficiency testing (PT) program was initiated in 2006 that included a panel of eight coded specimens (six unique and two duplicates) to participating laboratories. The number of participating laboratories increased from 12 to 38 from 2006 to 2009. Overall, 96.1% of the laboratories reported results, and 95.4% of those reporting achieved a 100% score. The observed mean normalized optical density (OD-n) values of all participants correlated well with the expected OD-n values for all specimens (R(2) = 0.98) used for seven PT rounds. BED testing demonstrated high reproducibility among all laboratories, with an agreement of 99.3% (574/578) between initial and confirmatory classification and regression statistics of R(2) = 0.96, slope = 1.022, and intercept = 0.0066. Reproducibility among duplicate specimens was very high during each PT round, with mean deviation of 1.8%. Analysis of controls and calibrator specimen for all 343 runs showed a coefficient of variation of ca. 20% for raw ODs in the dynamic range, which was reduced to <10% when the OD was normalized (OD-n). Most laboratories that failed the PT assessment had transcriptional errors, kit reagent problems, or specimen handling errors. Thus, the BED-specific PT program enabled us to track performance of different laboratories conducting the BED assay while identifying areas for improvements. This program will also serve as a template for future PT programs for new incidence assays as they become available.

Publication types

  • Evaluation Study
  • Multicenter Study
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Clinical Laboratory Techniques / methods*
  • Clinical Laboratory Techniques / standards*
  • HIV Antibodies / blood
  • HIV Infections / diagnosis*
  • HIV Infections / epidemiology*
  • HIV-1 / genetics
  • HIV-1 / isolation & purification*
  • Humans
  • Immunoenzyme Techniques / methods
  • Immunoenzyme Techniques / standards
  • Immunoglobulin G / blood
  • Incidence
  • Observer Variation
  • Quality Control
  • Reproducibility of Results
  • Virology / methods*
  • Virology / standards*

Substances

  • HIV Antibodies
  • Immunoglobulin G