The data presented below compares the results of a diagnostic test in the presence and absence of a disease. Test Result Disease Present Disease Absent Positive Test 40 5 Negative Test 10 95 Total 50 100 The specificity of the test is?
Specificity is the propoion of persons without the disease who are correctly identified by the test as being disease-free. It is given by TN/(FP + TN), where TN stands for true negatives (people who do not have the disease and test negative on the test) and FP stands for false positives (people who do not have the disease but test positive on the test). In this case, 95/(5 + 95) = 95/100=0.95.
0.05
0.4
0.8
0.95