The PCR Test is the gold standard of for detecting COVID-19 infection.
PCR Testing is by far the most reliable and effective method available for detecting an active COVID-19 infection, with around a 99.9% accuracy rate. This is due to the fact that a PCR Test directly detects the genetic material of the Sars-CoV-2 virus when it's present in the body. PCR is even capable of detecting leftover genetic fragments of the virus after you are no longer infected. This is the reason that the PCR Test is the only test used by healthcare providers for the purpose of formally diagnosing a COVID-19 infection.
Even outside of clinical diagnosis, it is always best to opt for using the PCR Test when at all possible.