Diagnostic Performance of laboratory tests

Question 1

What is considered when interpreting the results of lab tests?

Answer 1

Sensitivity
Specificity
Negative predictive value (NPV)
Positive predictive value (PPV)
Diagnostic efficiency

Question 2

Diagnostic Sensitivity

Answer 2

Indicates how truly patients with MI would produce a positive test result.

Diagnostic Sensitivity = no. of infarction patients with (correct) positive test results/ no. of all infarction patients tested

Question 3

Diagnostic specificity

Answer 3

Indicates the frequency of a negative result in patients who do not have an infarction

Question 4

Positive and Negative predictive values

Answer 4

It is the probability that the disease in question is actually present if the test result is positive (positive predictive value)

It is the probability that the disease in question is actually absent if the test result is negative (negative predictive value)

Question 5

Diagnostic efficiency

Answer 5

It is the overall proportion of correct (both positive and negative) test results for all the subjects tested.