HIV self-testers can use and interpret rapid tests as easily as a health worker
Self-testers are able to perform HIV tests and interpret the results as accurately as healthcare workers, a new evidence review has found.
The analysis, published in The Lancet HIV, assessed the reliability and performance of HIV rapid diagnostic tests carried out by self-testers compared with trained healthcare workers.
The review, which will be used to inform World Health Organization (WHO) recommendations on HIV self-testing, assessed 25 studies with sample sizes of between 22 and 5,662 participants, carried out in a diverse range of countries between 1995 and 2016.
As interest in HIV self-testing continues to increase, particularly as a way to reach people who are reluctant or unable to access existing testing services due to stigma, discrimination and criminalisation, wide-ranging evidence reviews such as this one are needed. Although previous evidence reviews on self-testing have been carried out, they have mainly been drawn from US and European studies, whereas this study consolidates evidence relating to people in low- and middle-income countries.
However, as the studies selected used reference standards that are unaligned with WHO guidelines, the generalisability of the evidence review is reduced.
The review includes 13 studies assessing unassisted HIV self-testing (where people carried out self-testing following manufacturers’ instructions included in the kit), 11 studies relating to directly assisted HIV self-testing (where people receive a demonstration of how to do the test or interpret the test result before carrying out the test themselves), and one study reported on both approaches. The majority of studies (15 in total) used oral fluid-based rapid diagnostic tests, six used blood-based rapid diagnostic tests, and four used both.
Its findings suggest that, in the hands of self-testers, blood-based rapid diagnostic tests give more accurate results than oral fluid rapid diagnostic tests, possibly due to the fact that there will be a lower quantity of HIV antibodies in oral fluid compared with blood.
The analysis found most invalid results occurred due to user error and manufacturing defects. However, researchers found no significant differences in the proportion of invalid results between the different type of testing approaches, suggesting that unassisted self tests are just as likely to obtain a valid result as assisted self-testing.
Errors in performance might be reduced if sample collection was made easier and clearer instructions were provided. In some settings, translation in local languages, clear and large print instructions for those with visual impairment, detailed images and descriptions, electronic documents, and video or audio instructions could lead to higher levels of correct usage. Other ways to avoid user errors include having more clearly identifiable kit components; reducing the volume of specimen needed to carry out a test; and intuitive single-step test kits with controlled and automatic specimen collection.
In addition, the study’s authors suggest self-testing kits should clearly state that people with reactive or invalid test results should seek further testing at a health facility. This is an important issue because evidence suggests that people living with HIV on antiretroviral treatment might be using HIV self-testing kits to check and reconfirm their HIV status, and could obtain a false-negative result.