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UNITAID PSI HIV S ELF- T ESTING A F R ICA. Usability and Validity of Oral Fluid Self-Tests Among Intended Users: Experiences from Malawi, Zambia And Zimbabwe Dr Euphemia Sibanda – on behalf of STAR researchers. Presentation outline. Need for optimisation of user instructions
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UNITAIDPSIHIVSELF-TESTING AFRICA Usability and Validity of Oral Fluid Self-Tests Among Intended Users: Experiences from Malawi, Zambia And Zimbabwe Dr Euphemia Sibanda – on behalf of STAR researchers
Presentation outline • Need for optimisation of user instructions • How optimisation was done in STAR • Accuracy of oral fluid tests among intended users • Planned work with blood-based tests
Instructions for use need optimisation • Understandable instructions for use (IFU) critical for accuracy • We conducted research to • explore participant understanding of IFU • optimise IFU • Methods included • Cognitive interviewing • Video - recording of unassisted self-testing • Accuracy studies comparing user results vs professional result • Findings informed toolkit development
Cognitive interviews “Tell me what you think it means.” …. “Now go ahead and do what you think it says.” * Incorporated Zimbabwe findings
Findings from cognitive interviews • Challenges interpreting symbols • Layout critical for understanding • Organisation of packaging • Spatial instructions inadequate • Importance of good translation • Purpose and use of equipment “Looks like a plate on a stove” Man aged 27, Zimbabwe Observed Intended “…but the picture doesn’t make sense. What does the cutlery mean?” Man aged 20, Malawi
Accuracy studies • Self-test results compared with national algorithm
Accuracy Results Self-test results compared with finger-prick RDTs (SOC) • Accuracy improved with demonstration • Lower accuracy among rural participants **Results exclude invalid self-tests**
How about clinical performance vs 4th Generation Laboratory gold standard? See poster TUPEC0842 • 2nd generation (IgG antibody only) tests have inherent limitations in sensitivity… • E.g. Early HIV infection • Important as we get closer to the first 90 • Zambian study used 4th Gen Abbott & BioRad as alternative reference standard OraQuick versus 4th Generation lab algorithm Agreement 98.5%, Cohen's kappa 0.9125 p<0.001 Sensitivity 87.6* (95% CI 83.0 - 91.4) Specificity 99.7 (95% CI 99.4 - 99.9) * Sensitivity of standard of care finger-prick RDT vs 4th Gen Lab: 93.5% (89.9-96.2)
Conclusions and recommendations • Optimisation of IFUs is important for each context • Can be marked urban:rural differences • Iterative cognitive interviews and accuracy studies – recommended in STAR toolkit under development • In Malawi, Zambia and Zimbabwe IFU alone insufficient – need for demonstration • With demonstration accuracy was good against Standard of Care reference (finger-prick RDTs) • Short video clip was adequate for this purpose • However, against 4th Generation Reference standard • Poor sensitivity for both Standard of Care and Oral Fluid HIVST • Mainly reflecting limitations of 2th Gen RDTs
Planned work in Malawi and Zimbabwe • IFU optimisation for two blood based tests • Including one 3rd Gen test • Accuracy among general population and female sex workers • Comparison of user preference and accuracy of the two tests
Acknowledgements • Study participants • Ministries of Health in Malawi, Zambia and Zimbabwe