1. Consider a screening test for ovarian cancer that has a sensitivity of 95%. Calculate what the specificity of the test should be for it to have a PPV of 80% given that the prevalence of the ovarian cancer in the given population is 0.05%?
2. Consider a screening test for a disease that has a sensitivity of 90%. Calculate what the specificity of the test should be for it to have a minimum PPV of 86% given that the prevalence of the given disease in the given population is 5%?