Medical tests. medical tests are used to indicate whether a person has a particular disease. the sensitivity of a test is the probability that a person having the disease will test positive (indicating the person has the disease, i. e., it’s the probability the test will pick up the fact that a person has the disease). the specificity of a test is the probability that a person not having the disease will test negative. a test for a certain disease has been in use for many years. based on the “track record” of this test, its sensitivity is 0.934 and its specificity is 0.968. finally, in the population, 1 in 500 people has the disease. what is the probability that a person who tests positive actually has the disease?