While the rapid test can get you results very quickly, the results may not always be accurate. Rapid tests are considered the most accurate in a patient who is having symptoms of COVID-19.

What does a false negative or false positive mean? 
In those who don’t have symptoms, the false-negative rate — meaning my test is negative but I actually have the disease — can be as high as 50%. This can have tremendous consequences as we try to contain the spread of COVID-19.

The false-positive rate — meaning I test positive but I do not really have the disease — is quite low. So, if you test positive from a rapid test it is more likely you do have the disease.