Suppose that a new screening test is proposed for the detection of fracture. The prevalence of fracture in the general population is known to be 10%. The test has been investigated in fracture subjects and was found to give positive result in 70% of such cases (sensitivity). When given to subjects without fracture, the test yielded a positive result of 20%.

a) What is the proportion (probability) of subjects will actually be found to have fracture with positive test?

b) What is the proportion (probability) of subjects will be found to have without fracture with positive test?

c) What is the overall rate of positive test result?