Date Published: January 26, 2010
Publisher: Public Library of Science
Author(s): Derryck B. Klarkowski, Juan Daniel Orozco
Abstract: Derryck Klarkowski and Daniel Orozco describe the Médecins Sans Frontières program for monitoring the quality of microscopy for malaria, pulmonary tuberculosis, and leishmaniasis.
Partial Text: The international humanitarian medical aid organization Médecins Sans Frontières/Doctors Without Borders (MSF) supports a wide network of medical laboratories in resource-constrained countries. Although MSF has always prioritized quality control (QC) for laboratory testing, prior to 2005 we were constrained by two significant limitations. First the QC workload was unsustainable in many programs, as MSF used the traditional protocol of reexamining 10% of negative slides and all positive slides. This is no longer considered practical –. Second MSF had no system for central data analysis as QC was performed independently at the individual laboratory level without standardized protocols.
The QC protocol was designed to (1) have a small sample size to be feasible across all settings; (2) enable reliable analysis; (3) monitor both false-positive (FP) and false-negative (FN) results; and (4) be applicable to all microscopy testing.
In contrast to stable programs, such as government health laboratory networks, MSF operates as an emergency humanitarian organization, and laboratory programs open and close according to changing priorities. Therefore the QC analysis presented here reflects the overall performance of MSF-OCA programs over 2005–2008 with a changing composition of laboratories.
We found the design of our QC protocol to be practical in field settings and easily understood and implemented by laboratory staff with limited training. We attribute this to a combination of a small QC sample size, a fixed number of slides independent of the workload, and use of simple percentage agreement for statistical analysis. The small sample size considerably decreased the QC workload while maintaining statistical reliability by using targeted sampling of only weakly positive slides and 4-month cohort analysis.
From this recent field experience, our laboratory QC protocol was found to be well accepted and understood by all levels of field staff, practical in a wide variety of contexts, able to improve performance, and able to provide valuable program management information. As with all QC, implementation and sustainability requires commitment from field staff and project managers. Ongoing supervision and support are critical for central monitoring, ensuring compliance, and regular feedback reporting. The implementation of this centralized-reporting, standardized QC program has provided the catalyst for MSF-OCA to develop a laboratory “culture of quality” over the past 3 years, which in turn has strengthened the commitment and interest of laboratory field staff to ensure the success of health care programs.