copy一段解析
https://publichealth.jhu.edu/2020/covid-19-testing-understanding-the-percent-positive
The percent positive is exactly what it sounds like: the percentage of all coronavirus tests performed that are actually positive, or: (positive tests)/(total tests) x 100%. The percent positive (sometimes called the “percent positive rate” or “positivity rate”) helps public health officials answer questions such as:
- What is the current level of SARS-CoV-2 (coronavirus) transmission in the community?
- Are we doing enough testing for the amount of people who are getting infected?
