Background
Self testing for HIV is a targeted intervention with the potential to increase the access, uptake and frequency of HIV testing and more effectively reach the undiagnosed, especially in priority populations. The objectives of this study were to (1) evaluate the INSTI HIV self-test performance compared with laboratory reference testing, (2) document if intended users can perform the steps to use the HIV self-test device, and (3) document if intended users can successfully interpret contrived positive, negative, and invalid results. Study was intended to be submitted to Health Canada for review for regulatory approval purposes.
Methods
The study used a cross-sectional design and recruited consenting adults who were representative of intended users of HIV self-testing from four community sites across Ontario, Québec, and Manitoba between August 2019 and March 2020. The results of the observed HIV self-test were compared with results of the Abbott Architect HIV Ag/Ab Combo test. Usability outcomes for critical (e.g., lancing finger, blood droplet into bottle, shaking bottle four times) and noncritical self-test procedure steps were also determined.
Results
Overall, 77% (n = 522) of participants were between 18 and 45 years of age, 61% (n = 410) were male, 71% (n = 480) had some college or more education, and 45% (n = 307) were employed; identity for race and ethnicity: Caucasian (44%; n = 296), African, Caribbean or Black (17%; n = 113), Indigenous [First Nations, Métis or Inuit] (14%; n = 95), Asian (16%; n = 106), Latin American (7%; n = 46). Primary performance analysis on 678 completed HIV self-tests revealed a positive percent agreement of 100% (5/5, 95% CI: 43.6–97.0%) and a negative percent agreement of 99.5% (614/617, 95% CI: 98.6–99.8%) with the comparator method. The overall percent agreement of results interpretation between participant and observer was 93.5% (n = 633). For the 708 participants who took part in the usability study, the average success rate for steps determined to be “critical” for successful completion of the test was 92.4%. 97% (n = 670) of participants found the instructions easy to follow, and 95% (n = 655) of participants indicated that they would use the test again. Of the 404 participants who interpreted the strong positive, weak positive, negative, and invalid contrived results, successful interpretation ranged from 90.6% (for weak positive, n = 366) to 99.3% (for negative, n = 401).
Conclusions
The addition of a regulatory-approved self-test into the Canadian HIV testing landscape could significantly increase HIV testing rates. Having a blood-based HIV self-test approved in Canada can offer an accurate, acceptable, and simple alternative to facility-based HIV testing, particularly when impacted by Coronavirus pandemic restrictions.