What does the term 'sensitivity' indicate in medical testing?

The term 'sensitivity' in medical testing refers to the ability of a test to correctly identify individuals who have a particular disease or condition. It is calculated using the formula: true positives divided by the sum of true positives and false negatives. This means sensitivity quantifies how effectively a test can detect the presence of a disease when it is truly there.

A high sensitivity indicates that the test is good at ruling out disease in the population being tested, meaning that very few patients who have the disease will receive a negative test result (i.e., they will be misclassified as disease-free). This characteristic is crucial, particularly in screening programs, where it’s important to detect as many cases of a disease as possible.

In other options, the measurements represent different aspects of test performance. The calculation involving true positives and false positives indicates specificity, while true negatives divided by true positives provides information on test positivity not related to actual disease presence. Therefore, understanding sensitivity is vital in contexts where early detection and treatment can significantly affect outcomes.