You want to do sequential heart disease (HD) screening in a hospital-based population of 5,000 subjects. For the first stage, assume that
the CAC test has a sensitivity of 95 percent and a specificity of 66 percent. For the second stage, assume that the cardiac catheterization
has a sensitivity of 95 percent and a specificity of 90 percent. Assume a prevalence of heart disease in this population of 10 percent.
a. How many true positives do you get in this population using only the CAC test?
b. How many true negatives do you get in this population using only the CAC test?
c. What is the PPV using only the CAC test?
d. How many subjects will be given the cardiac catheterization test?