A total of 767 participants were recruited over the study period. Of the 767 participants that started the process, 89 participants were excluded from the Primary Efficacy Analysis according to the exclusion list (see Appendix B for full list of excluded participants). Recruited participant numbers varied across the performance, usability and mock results interpretation arms of the study as not all recruited participants completed all elements.
Table 1 shows the demographic profile of participants included in the primary efficacy analysis (n=678). Over 75% of the sample was between the ages of 18 and 45 years of age. Over 60% identified as “male” and 37% as “female” (for the 21 who chose “other”: 8 were “Trans” people, 8 identified as “non-binary”, 1 as “agender”, 3 as “queer”, and 1 as “Two Spirit”). There were two participants who identified that they were pregnant. In terms of ethno-racial composition, approximately 44% identified as “White”, 17% as “Black”, 14% as “First Nations, Métis or Inuit”, 16% as “Asian”, 7% as “Latin American”, and the remaining 2% as “other”. In terms of educational achievement, approximately 27% of the sample completed High School, 23% completed College, and 48% a University degree or higher. Less than 5% indicated having any kind of reading or writing impairment. In the sample, 89% identified as “right-handed” and 55% indicated use of reading glasses. Approximately 45% were employed, 23% were unemployed, 13% were students, 2% were retired, and 17% preferred not to answer.
In terms of self-reported HIV status, 20% indicated that their status was unknown or had never been tested, while 80% indicated that they were HIV-negative. When asked about HIV testing, 74% indicated having prior experience with testing. When evaluating self-reported risk category for HIV, 600 participants (89%) were considered “high risk” for HIV infection. For specific self-reported sexual behaviours in the year prior to survey, 30% identified as having condomless sex with men while 18% had condomless sex with women. Approximately 30% of participants indicated having multiple sexual partners in the past year, 26 individuals (4%) indicated that their sexual partner was living with HIV, and 51 participants (8%) indicated having ever injected drugs.
Primary Efficacy (Performance) Analysis
After removing the 89 subjects who met the exclusion criteria from the 767 recruited participants, the primary efficacy analysis on the 678 who completed HIV-ST revealed a positive percent agreement of 100% and a negative percent agreement of 99.5% when comparing the valid self-tester results to the Abbott Architect (see Table 2 for full comparison of participant and laboratory test results and Table 3 for PPA and NPA calculations). The overall percent agreement between participant and observer for the self-test results was 93.5% (see Table 4 for full comparison of participant and observer interpretations of HIV-ST results). The overall “invalid” rate for the HIV Self-Test was 5.6%.
Usability Assessment Analysis
From the total of 767 study participants, 59 subjects withdrew after consenting, did not have a venous blood sample collected or did not complete the self-test, leaving 708 available for analysis with the usability assessment. Overall, the average for all desired outcomes was 91.8% and for the 12 critical items, the average was 92.4% (see Table 5 for full breakdown of usability questions). Despite as instructed by the kit instructions for use, only 47.2% of participants were observed to have washed and dried their hands. Just over 92% of participants were able to lance their finger correctly, and 88.7% were able to form a blood droplet, but there was a considerably lower number of participants (81.2%) who were able to get the blood droplet to fall directly into Bottle 1.
Following the fingerstick blood collection, there were three types of procedures carried out as part of the test process: (1) shaking bottles (accomplished with range of 88.8% to 90.2% of time), (2) pouring contents into the test device (97.3% to 99.0% of participants did so correctly), and (3) waiting for liquids to disappear before adding next liquid into device (participants did this procedure 98.0% to 98.2% of the time). Over 89% of participants performed the procedural steps of the self-test in the correct order, while less than 10% missed any steps and yet continued the process despite this, and only 1.0% quit the process before the test was completed.
Table 6 shows the results from the self-test questionnaire given to each participant. Regarding the instructions for use, 96.7% of participants found them easy to follow. In terms of device use, over 90% of participants indicated that they were confident with performing the test on their own, and 96.2% found the device easy to use. Approximately 95% of participants indicated that they would use the test again and would also recommend this test to a sexual partner or friend. In terms of where participants would prefer using the self-test, 58.6% indicated that they would do the test at home, while 41.1% indicated that they would prefer to do the test at a clinic.
Mock Test Interpretation Results
A total of 404 participants volunteered to complete the mock test interpretation (see Table 7 for a full breakdown of mock test results). Overall, 97.8% of participants correctly identified a “strong positive”, 90.6% a “weak positive”, 99.3% a “negative” result, 97.8% an “invalid” (with no control, no test) result, and 93.6% an “invalid” (with no control, with test) result.