Crowded Probabilities in Tests for the Presence of Infection

In the presentation, problems have been addressed in perception and popular delusions in the interpretation of information related to the level of confidence / uncertainty of tests by which the presence or absence of contamination is verified. The theoretical essence of the probabilities of a false positive and false negative result, as well as the level of confidence / uncertainty of the test results and on this basis there are assumptions about the perception of such information and possible misconceptions in its interpretation by society. Assumptions made are checked on the information based on a non-reporting survey. The results obtained reveal user difficulties in rationalizing and interpreting the data provided as well as when detecting logical links characteristic of such information.