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Improving the Quality of Diagnosis: The countries of the Region have been switching responsibility for malaria diagnosis from the vertical structure of national programs to the health systems. The multiplicity of actors, the instability of human resources, and the greater structural complexity of this service network impose ever-growing challenges in terms of microscopy quality assurance systems.

Microscopy quality assurance activities were expanded to a region-wide initiative to support the improvement of the systems for quality of microscopic diagnosis in the general context of diagnosis networks at the malaria control programs.

The RAVREDA/AMI approach is based on a situation diagnosis followed by a meeting of a technical group in Caracas in 2004. At that meeting, a guide was prepared to provide orientation on improvements in diagnostic quality management activities in the Region.

The RAVREDA/AMI Approach

Introducing changes in the methodology used by the countries for performance monitoring (known in the Region as "indirect evaluation" or "slide validation") was recommended by the expert committee. As a new element in the system, it proposed including an "external laboratory evaluation" and a "microscopist competency assessment" utilizing panels prepared using standardized procedures. The recommended changes would improve the effectiveness of the system and allow for quality control in the laboratories, which are at present overwhelmed by indirect evaluation (thus addressing the problem using a more comprehensive approach). More time would be dedicated to increasing the availability of supervision and feedback. These activities were promoted by RAVREDA in the countries of the Region, in conjunction with local efforts and South-South cooperation activities to train human resources in the countries with the greatest limitations.

Objectives were:

  • microscopistTraining to improve competencies.
  • Introducing proficiency testing as a component of diagnostic quality assurance sistems (DQAS) (laboratory external evaluation and microscopist competency assessment).
  • Increasing the efficiency the performance monitoring (slide validation).
  • Utilizing prescribed methodology for proficiency testing (competency assessment).

Competency assessment

It consists of evaluating microscopists working at the different levels through proficiency tests, with panels prepared in the reference laboratories of each country to certify their capabilities. To date, this assessment mechanism has not generally been used by malaria programs in the Region. An expert group convened by WHO in 2005 and 2006 issued specific recommendations on competence assessment and certification that helped reorient the approach proposed in the framework of RAVREDA/AMI in 2004, emphasizing the importance of this component within the system and considering issues such as setting criteria for training microscopists at the network level and setting up evaluation panels, as well as establishing scoring and certification criteria.

Methodology for Slide Validation (Performance Monitoring)

Performance monitoring, known as "indirect evaluation" or "slide validation" in the Region's malaria diagnostic networks, is the primary activity in quality control systems in the countries. As recommended by the practices inherited from the vertical program, evaluation of 10% of negative slides and 100% of positive slides has been maintained, with some variation between countries. However, there are several weaknesses in this evaluation mechanism, in that there is no clear rationale for this practice, which creates a heavy workload for the validation laboratories. The approach promoted by AMI proposed changes in the methodology. Some of the most noteworthy recommendations were:

  • Reduce the frequency of evaluation (when greater than monthly) to reduce the workload of the reviewers.
  • Reduce the number of slides to be evaluated in each period.
  • Randomized selection of slides to be validated by a third party.
  • Blind validation of slides by the validation laboratory.
Related Links:

:: Program for External Performance Evaluation in Microscopic Diagnosis of Malaria

:: Malaria microscopy training CD-ROM

External Performance Evaluation Program

Quality control of malaria diagnosis in the countries of the Region is marked by the predominance of indirect evaluation activities (the periodic shipment of material from local laboratories to intermediate laboratories and, in some cases, from that level to a national reference laboratory). This system is only partially functional in some countries, and the prevailing methodology permits the introduction of biases into the evaluations. In the majority of cases, the system demands excessive time and human resources without necessarily meeting the quality objectives. The need for an External Performance Evaluation Program (EPEP) for national reference laboratories is the reason for this protocol. This program will not only improve malaria diagnosis at the reference centers, but permit the transfer of skills and the upgrading of resources in the countries through South-South cooperation.

 Relevant Documents

Last Updated on Sunday, 09 November 2014 15:49

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