Positive or negative refers to the results of the new crown nucleic acid test, positive is problematic, more suggestive of infection with the new crown; negative is not a problem. 1. Positive nucleic acid test for new crowns: new crowns can generally be tested on nasal swabs, pharyngeal swabs, anal swabs, etc. If the test result shows positive, it suggests that there may be infection with the new crowns virus infection, which is problematic. Due to specimen collection cross-infection can also occur false positives, but this situation is generally less likely to occur, can be reviewed and other checks to clarify the diagnosis. 2. Negative new crown nucleic acid test: if the new crown nucleic acid test, the results show negative, generally there is no problem, indicating that there is no infection with the new crown virus. However, due to the sampling site, the patient’s onset time, etc., false negatives may occur. Nucleic acid test needs to be performed again and combined with imaging, hematology and other tests for comprehensive diagnosis.