Negative and positive are widely used in medicine, and have become a term to indicate the existence or not, or to indicate the results of an examination. Common ways are as follows:
1, indicating the physical examination results: if someone suffers from coronary heart disease or tuberculosis in a small area, the doctor may not find the problem by auscultation, so he will say that there is no positive sign of heart and lung, or heart and lung are negative, or write it as heart and lung (-).
2. Test result: Do tuberculin test. If there is no local redness, it is called OT(-), which means that there is no immunity to tuberculosis, and BCG should be inoculated.
3. Show the test results: hepatitis B "two and a half times" test .. If E antigen is positive (+), it means that it is highly contagious. If only the surface antibody is positive (+), it means that it is immune to hepatitis B virus, but it is generally not contagious.
Extended data:
Similarly: false positive
Positive (+) indicates that the disease or physiological changes in the body have certain results. On the contrary, a negative (-) on the test sheet or report basically denies or excludes the possibility of a certain lesion. However, due to environmental factors, operational factors, experimental methods or patients' own factors, people who do not have positive symptoms may be detected as positive results.
Baidu encyclopedia-false positives
Baidu Encyclopedia-Negative