In the case of the New Crown Antigen kit, for example, two bars represent a positive, but there is a certain probability that it is a false positive. The new crown antigen reagent for the test person negative, positive judgment mainly depends on the reagent strip C and T changes. If a bar appears at both C and T after the test, the test subject can be initially judged to be positive. If only a bar appears at C, the test subject is negative. If there is no change at C, the test is invalid regardless of whether a bar appears at T, as C is the quality control area. If the test subject is positive after using the new crown antigen reagent, he/she may be infected with the new crown, and should be observed and treated at home in a timely manner, and if there are symptoms such as fever, cough, or fatigue, the symptoms should be treated in a timely manner. If symptoms worsen after infection, prompt medical attention is recommended.