Sensitivity and Specificity: How Good Is That Test, Really?
Recently I spoke with a medical diagnostics company that is developing blood tests to detect cancer at a very early stage. I was fascinated. We all know: the earlier we catch a disease, the more options we have to treat it.
When reading research papers around diagnostic tests, two terms appear constantly: sensitivity and specificity. These two concepts are central to understanding how good a test really is. Yet they can be confusing—even for people with medical training.
In this post, I’ll walk you through what sensitivity and specificity mean, using simple examples that still respect the science.