Rapid tests for malaria: what do health workers think of them?

12 May 2010

Paul Chinnock

Source: Malaria Journal (see original article or PDF)

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Citation: Chandler CI, Whitty CJ, Ansah EK (2010). How can malaria rapid diagnostic tests achieve their potential? A qualitative study of a trial at health facilities in Ghana. Malar J ;9:95.

Performing rapid diagnostic testing in the field. [Credit: Foundation for Innovative New Diagnostics (FIND).]

Most Africans who receive treatment for malaria do so without a confirmatory test for the disease being carried out. According to reports received by WHO in 2008, 78% of malaria cases were diagnosed on the basis of symptoms only; no laboratory tests were done [1]. The use of so-called “presumptive treatment”, which assumes that a patient with fever in an endemic area most likely has malaria, has always carried problems and – thanks to the progress against the disease made in recent years – an increasing proportion of cases of fever are due not to malaria but to other infections. Presumptive treatment results in overprescribing of costly antimalarials, and many patients who would benefit instead from antibiotics do not receive the treatment they need.

Fortunately, technological advances have led to the availability of rapid diagnostic tests (RDTs) at affordable prices. RDTs can be used by health workers at primary care level even in remote areas. No lab facilities are required.

The first question about these new tests is whether they work; do they give accurate results in the settings where they will be used? A report published in May 2009 (and discussed on TropIKA.net) concluded that some tests on the market perform extremely well in tropical temperatures and can detect even low parasite densities in blood samples, though others are only able to detect the parasite if is present at high densities. And a newly released assessment of the performance of 29 rapid diagnostic tests has found that 15 of them meet minimum performance criteria set by WHO. The authors of this latest assessment stress that, “There are a clear set of criteria related to local conditions that need to be considered in deciding the best diagnostic test for a particular country”. [The assessment was undertaken by the Special Programme for Research and Training in Tropical Diseases (TDR), the Foundation for Innovative New Diagnostics (FIND) and WHO’s Global Malaria Programme. It is available from the TDR website.]

But a second question also needs to be considered – what do primary healthcare workers who have been using RDTs on the front line think of them? New research from Ghana has addressed this issue in a qualitative study, in which interviews were used to explore in depth the experiences of 13 health workers in four rural health care centres who had experience of using RDTs.

The health workers’ experience was gained during a trial [2] that sought to measure whether the introduction of RDTs reduced overprescribing. The trial found that while introduction of RDTs in rural health facilities did achieve such a reduction, nearly half of patients who tested negative with RDTs were still prescribed an antimalarial. Clearly, it is important to find out why so may test results were apparently ignored.

For the health worker interviews, the researchers used “purposive sampling” to ensure that the staff who they spoke to ranged from those who continued to prescribe antimalarials to most patients with negative RDT results to those who largely restricted antimalarials to patients with positive RDT results.

The lengthy published paper includes many of the comments the health workers themselves made. Some appreciated the benefits of RDTs but others said they were worried that the test might have missed “hidden” parasites and that there might be serious consequences for the patient if antimalarials were not given. They said that the test results often conflicted with their clinical judgement. The health workers’ own lack of confidence in the tests was not the only issue; they noted that they faced pressure from patients who demanded antimalarials, even when told their tests were negative. The health workers appeared to be lacking in support from the health system and the suppliers of the tests to help build their confidence in RDTs.

The authors point out that introduction of the tests represents a big change in long-standing working practices and that the health system showed a “limited readiness” to accept such a change. They conclude that, if RDT results are to be adhered to, “…more attention needs to be given to supporting interventions to help providers to change a long-standing paradigm of malaria overdiagnosis”. They propose three sets of such interventions:

unambiguous and consistent guidelines for health workers
advocating the benefits of RDTs to both providers and patients and providers, using “trouble-shooting schemes with RDT or diagnostic experts”
readying local health facilities for the major change in practice that is entailed and providing them with support.

The original trial [2] demonstrated that even an effective intervention (such as the RDTs used here) can fail to achieve the intended objectives if practical considerations are not given adequate attention. While this is a study involving only 13 health care providers, it provides valuable insights into the barriers that must be overcome on the front line of care. Handing out new tools to health workers is not enough; they need to be supported in their use of them.

Reference

1. WHO Technical Consultation on Parasitological Confirmation of Malaria Diagnosis. Report. Geneva, World Health Organization, 2010. (Unpublished).

2. Ansah EK, Narh-Bana S, Epokor M, Akanpigbiam S, Quartey AA, Gyapong J, Whitty CJ (2010) Rapid testing for malaria in settings where microscopy is available and peripheral clinics where only presumptive treatment is available: a randomised controlled trial in Ghana; BMJ; 340:c930. Available from: http://www.ncbi.nlm.nih.gov/pubmed/20207689

2010 Chandler et al; licensee BioMed Central Ltd.

Source

Title:
How can malaria rapid diagnostic tests achieve their potential? A qualitative study of a trial at health facilities in Ghana.

Authors:
Chandler CI, Whitty CJ, Ansah EK

References:
Malar. J. 2010: Vol. 9, pp. 95

Abstract:
BACKGROUND: Rapid diagnostic tests (RDTs) for malaria are at the early stages of introduction across malaria endemic countries. This is central to efforts to decrease malaria overdiagnosis and the consequent overuse of valuable anti-malarials and underdiagnosis of alternative causes of fever. Evidence of the effect of introducing RDTs on the overprescription of anti-malarials is mixed. A recent trial in rural health facilities in Ghana reduced overprescription of anti-malarials, but found that 45.5% patients who tested negative with RDTs were still prescribed an anti-malarial. METHODS: A qualitative study of this trial was conducted, using in-depth interviews with a purposive sample of health workers involved in the trial, ranging from those who continued to prescribe anti-malarials to most patients with negative RDT results to those who largely restricted anti-malarials to patients with positive RDT results. Interviews explored the experiences of using RDTs and their results amongst trial participants. RESULTS: Meanings of RDTs were constructed by health workers through participation with the tests themselves as well as through interactions with colleagues, patients and the research team. These different modes of participation with the tests and their results led to a change in practice for some health workers, and reinforced existing practice for others. Many of the characteristics of RDTs were found to be inherently conducive to change, but the limited support from purveyors, lack of system antecedents for change and limited system readiness for change were apparent in the analysis. CONCLUSIONS: When introduced with a limited supporting package, RDTs were variously interpreted and used, reflecting how health workers had learnt how to use RDT results through participation. To build confidence of health workers in the face of negative RDT results, a supporting package should include local preparation for the innovation; unambiguous guidelines; training in alternative causes of disease; regular support for health workers to meet as communities of practice; interventions that address negotiation of health worker-patient relationships and encourage self-reflection of practice; feedback systems for results of quality control of RDTs; feedback systems of the results of their practice with RDTs; and RDT augmentation such as a technical and/or clinical troubleshooting resource.

PMID: 20398262
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