SAGE IVD recommended including the sickle cell testing test category in the EDL 3:
• as a disease-specific IVD for use in community settings and health facilities without laboratories (EDL 3, Section I.b, Sickling disorders);
• using a rapid diagnostic test format;
• to screen for or to aid in the diagnosis of sickle cell disease, sickle cell trait and other sickling disorders.

SCD is a global health problem that contributes to excess mortality in children under 5 years of age; early recognition in infants is critical. Last year, sickle cell testing using electrophoresis was added to the EDL 2, and SAGE IVD requested the submission of a POC test. The type of POC test under consideration is a simple, accessible test that can be used in rural settings. It is cheaper compared with gold standard tests, such as electrophoresis. While there is no systematic review available for the products under this test category, there are sufficient large, well-designed studies to show that they are very accurate. SAGE IVD noted that no studies for implementing the tests were submitted but acknowledged that, as new tests, it is unreasonable to expect evidence on clinical impact. The group also noted that since the test category was submitted for consideration, the findings of a pilot implementation of one of these products in Nigeria have been published. Some concerns were raised about the tests’ lack of international regulatory approval, despite one of the commercially available tests holding a CE mark (in this case the CE mark is self-declared without any independent evaluation since the test is considered a low-risk IVD in the European context). Given the geographic distribution of the sickle cell gene, the test is unlikely to ever get stringent oversight from a regulatory authority in any of the founding members of the Global Harmonization Task Force (Australia, Canada, European Union, Japan or United States of America). One WHO expert also raised concerns about the potential for the addition of a POC RDT to the EDL to divert much-needed resources away from gold standard tests. But the recent report from Nigeria shows the tests can be procured for less than US$ 2. Some concerns were also raised about how the test could and should be used. Clarity of purpose was emphasized as important, especially given that some countries have high prevalence of both SCD and thalassaemia and need to be able to differentiate between the two. SAGE IVD cautioned against using DBS as a specimen type because of a lack of evidence and regulatory oversight of the DBS protocol.

The evidence base for these tests is in its infancy, with no systematic review available nor any studies of test impact. The primary studies provided indicate that the tests have very high sensitivity and specificity. The studies have generally been well done, recruiting appropriate populations. Many used discrepant analysis to resolve differences between the reference standard and the POC test; but the possible bias this will have introduced is small, as there have been very low numbers of discrepant cells. Several large, well-designed studies have shown the POC test for sickle cell disease and trait to have high accuracy, with sensitivities and specificities > 97% across newborns, children and adults. There is no evidence as yet of the impact of using the test.

World Health Organization. (‎2021)‎. The selection and use of essential in vitro diagnostics: report of the third meeting of the WHO Strategic Advisory Group of Experts on In Vitro Diagnostics, 2020 (‎including the third WHO model list of essential in vitro diagnostics)‎. World Health Organization. https://iris.who.int/handle/10665/339064