Yes, clinical studies have shown that the overall accuracy is rated at over 99%, meaning that there is over a 99% probability that either a positive or a negative result will be correct.
Sensitivity and specificity
Sensitivity of a test is defined as the percentage of test results that will be positive when HIV is actually present. Specificity of a test is defined as the percentage of test results that will be negative when HIV is not present.
The INSTI HIV antibody test is very sensitive and specific, with sensitivity shown in clinical trials to be 99.6% (i.e., the percentage of results that will be positive when HIV is present). This means, however, that it may fail to detect up to 4 instances of HIV out of every 1,000 instances of testing where HIV is present, and that up to 4 false negative results could be expected out of every 1,000 self-tests in individuals who have HIV.
When the test is done correctly, it will detect HIV antibodies more than 99% of the time once the body’s immune response has produced enough antibodies. However, a positive self-test result does not necessarily mean you have HIV, since it still needs to be confirmed by a follow-up blood test by a laboratory.
If you get a positive result, you will need to see a health care provider (e.g., sexual health clinic, physician) to obtain a confirmatory test. Visit our Care pathways pages on this website to learn more about where you can find confirmatory testing in your province or territory.
Specificity of the INSTI self-test was shown to be 99.5% (i.e., the percentage of results that will be negative when HIV is not present) when performed by untrained users in a Canadian study. This means that up to 5 false positive results could be expected out of every 1,000 self-tests in individuals who do not have HIV. This is an important reminder for people to obtain confirmatory testing of all self-test positive results.
A positive result can appear within 21-22 days after exposure to HIV, but could take up to 3 months to show. People should test frequently during the window period, which is 3 months from the time when HIV might have been acquired.
Following instructions carefully for the most accurate results
To ensure the maximum accuracy of the self-test, it’s very important for people who are self-testing to carefully read and follow all labeled instructions. Even when used according to the labeled instructions, as noted above, there will be a small number of false negative and false positive results. For more details, please watch the instructional video on using the test. If the self test is performed incorrectly, or if not enough fingerstick blood is collected, there is a risk of getting an invalid result. If this happens, visit our Post-test counselling: invalid result page to learn about what you can do if you receive an invalid result.