The second bar of the antigen self-test is not obvious, it may be a weak positive result, but there is a large error in the antigen measurement paper, it is recommended to go to the hospital for nucleic acid test confirmation. The new crown antigen test is mainly to detect their own antigen, but the antigen results compared to the results of the nucleic acid test error, sensitivity and specificity are poor, easy to false negative or false positive results, if the new crown test value of the second bar is not obvious, it is recommended that timely consultation for nucleic acid testing to confirm whether the new crown infection. The second bar of the new crown antigen test is not obvious, it may be the early stage of the new crown virus infection, due to the low viral load, there is a window period, the kit does not detect the new crown new coronavirus, there may be false negatives, you need to carry out a review to confirm the diagnosis, and help determine the accuracy of the results of the antigen self-test. The new crown antigen self-test kit is only used as a preliminary testing method. The results are still based on the nucleic acid test. In case of weak positivity, it is recommended to review the test promptly.