What does "sensitivity" refer to in diagnostic testing?

Sensitivity in diagnostic testing refers specifically to the test's ability to correctly identify individuals who have a particular disease or condition. It is a measure of the proportion of actual positives (those with the disease) that are correctly identified by the test. A high sensitivity indicates that the test is effective at detecting the disease, which is crucial for conditions where early diagnosis can significantly affect patient outcomes. For instance, a test with 90% sensitivity means that 90% of people who have the disease will test positive, minimizing the risk of false negatives.

Considering the other concepts, predicting outcomes relates more to the test's specificity and predictive value rather than sensitivity. The speed of the test results is about the time taken to deliver results, not the accuracy in identifying the condition. The quality of the specimen collected can affect the test's reliability but is not a direct measure of sensitivity. Hence, the focus of sensitivity is clearly on the correct identification of those with the disease, making it a critical factor in evaluating the effectiveness of diagnostic tests.