Laboratory Medicine

Question 1

Qualitative vs Quantitative testing

Answer 1

Qualitative = +/-, yes or no, etc

Quantitative = An actual number

Question 2

Screening

Answer 2

To identify risk factors for disease and to detect occult disease in asymptomatic persons

Question 3

What should be considered before running a test

Answer 3

Cost of the test

Associated risks

Potential for additional testing

Always ask yourself “will the results of the testing change the management”

Question 4

Accuracy

Answer 4

Determined by its correspondence with the true value

Question 5

Precision

Answer 5

A measure of the reproducibility of the test

Tests can be precise but innaccurate

Question 6

Sensitivity

Answer 6

The ability of a test to detect the presence of disease

Expressed by the number of patients who have the disease and test positive

Question 7

SNOut

Answer 7

A highly SENSITIVE test with a NEGATIVE result is helpful for ruling OUT the disease

Question 8

Specificity

Answer 8

The ability to detect an absence of disease expressed as the percentage of patients WITHOUT disease and test negative

Question 9

SPIn

Answer 9

A highly SPECIFIC test with a POSITIVE result is helpful for ruling IN the disease

Question 10

Pretest probability

Answer 10

The ability to decide if it will be beneficial to run a test based on risk factors, symptoms, history, and PE.