Overall, DBS HIV tests are very accurate. In people with HIV infection, the DBS HIV test will be correct more than 99 times out of every 100 tests.
If a person becomes infected with HIV, the DBS HIV test may not detect HIV for up to 12 weeks after the person has the infection. This is called the ‘window period’ where a very small number of tests can give a ‘false negative result’. This means the test result can be negative even if a person has HIV infection.
A very small number of tests can also give a ‘false positive result’, which means the test result is positive, but the person does not have HIV infection. This is clarified through further testing.