Both the COVID RT-PCR test and the COVID antigen test detect the presence of a COVID-19 infection. The indications for both vary. It has been observed that when an individual shows symptoms of a viral illness or reports a prolonged exposure to an infected individual for a long time, they can take an antigen test to assess the presence of the infection.
But research suggests that a COVID RT-PCR test is more accurate and reliable in diagnosing a COVID-19 infection effectively at an early stage. It can do so with or without the presence of symptoms.
According to research, the accuracy of the antigen test is around 60-70%, while the accuracy of the COVID RT-PCR test is approximately 90%. So, if you are suffering from mild symptoms, you might prefer antigen, but if you are suffering from major symptoms for a long time, then the COVID RT-PCR test is suggested.