Question

(1) Suppose you are a physician and have examined a patient whom you believe has a 30% chance of having deep venous thrombosis (clots in the veins of the leg). You decide you will treat the patient with anticoagulants (blood thinners) if further testing increases his probability of disease to 85% or more. Similarly, you will send the patient home without treatment if you can reduce his probability of disease to less than 10%. You have a choice of 2 tests, A and B, with the characteristics below. Which test will give you a clear answer about what to do? Defend your answer. True positive rate False positive rate = P(T ID) .20 05 Test A Test B 95 85 (a) (b) (c) (d) Either test will do it Test A will; test B won't Test B will; test A won't Neither test will do it

Answer 1

In T EST A the true positive rate is 0.95 it means that 5% chances of error occurred and false positive rate is 20%.In test B the true positive rate is 0.85 it means that 15% of chances of error occurred and false positive rate is 5%..In test A the minimum chances to error occurred.so we can do Test A not Test B.