QASI, an international quality management system for CD4 T-cell enumeration focused to make a global difference

A significant worldwide mobilization effort to treat people with HIV disease began in 2003. Most guidelines for initiating antiretroviral therapy require reliable and reproducible CD4 T-cell counting. Therefore, any effort that improves global availability of quality managed assessment schemes for CD4 T-cell enumeration is a positive achievement for the clinical management of AIDS on a worldwide scale.

The Canadian QASI-Quality Management System (QMS) has been in operation for over a decade. More recently, QMS has fine-tuned its strategy to optimize its global impact in the fight against the HIV/AIDS pandemic. Three modifications were implemented: (1) introduction of skills and knowledge transfer workshops pertaining to the initiation of national quality management programs for CD4 counting, (2) introduction of a road map to establish domestic EQAP for countries that are ready, and (3) introduction of a statistical analysis package which permits continuous monitoring of global impact of the QASI-QMS.

Based on QASI-QMS distribution of specimens over four consecutive participation cycles, there was decreased interlaboratory variation for both low and medium CD4 T-cell levels. After three cycles of consecutive participation, there is an average of 38 and 26% error reduction reported for the mid and low CD4 levels, respectively.

The program improvements mentioned earlier appear to have had a profound effect with regard to enhancing the performance of laboratories participating in the QASI-QMS. Specifically, there is a significant reduction in interlaboratory variability of CD4 T-cell counts resulting from continuous participation in the QASI-QMS.