Question

Describe the following for a given test: 
Sensitivity. 
 

Hint:

A highly sensitive test is useful for ruling out diseases (i.e., a negative result rules out the disease).

Answer 1

Step 1: Defining Sensitivity.
Sensitivity, also known as the true positive rate, refers to the ability of a test to correctly identify those with the disease or condition. It is the proportion of true positives among all those who actually have the disease.

Step 2: Formula for Sensitivity.
\[ \text{Sensitivity} = \frac{\text{True Positives}}{\text{True Positives + False Negatives}} \] Where:
- True Positives (TP): The number of people who actually have the disease and test positive.
- False Negatives (FN): The number of people who have the disease but test negative.

Step 3: Conclusion.
A high sensitivity means that the test is good at detecting those with the disease and has a low rate of false negatives. It is particularly important in screening tests where detecting the disease is crucial.