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Understanding test results
Every home result needs context: positive results need confirmation, negatives can be early, and invalid tests should be repeated.
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Positive or reactive
A positive result suggests the marker the test looks for was detected. It is not a diagnosis. Contact a GP or sexual health clinic for confirmatory testing and, if needed, treatment. Avoid sex until you have had advice.
Negative
A negative result means the marker was not detected in that sample at that time. If you tested within the window period, still have symptoms or had a recent exposure, you may need to test again or seek clinical advice.
Invalid
If the control line does not appear, the test has not worked and the result cannot be read. Use a new test and follow the instructions carefully.
Related on CareFree Kits
Sources
- NHS – Sexually transmitted infections (STIs) (nhs.uk/conditions/sexually-transmitted-infections)
Last reviewed 5 November 2026. This guide has not been clinically reviewed by a named professional.