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Analyzing a clinical test

How accurate is a clinical test? The answer depends on both the properties of the test, and on the population it is used in. Answer the three questions below to compute the predictive values of a test (the fraction of positive test results that are true positives, and the fraction of negative tests that are true negatives):
Sensitivity (%): Percentage of those with the disease who have a positive test.
Specificity (%): Percentage of those without the disease who have a negative test.
Prevalence (%): Percentage of those tested who have the disease.