The person you're replying to isn't incorrect. He was saying that having few tests that your treat as predictive isn't as helpful as a long line of tests that a

The person you're replying to isn't incorrect. He was saying that having few tests that your treat as predictive isn't as helpful as a long line of tests that are interpreted over time as predictive. Your example is someone taking a test and immediately moving ahead with treatment. Not someone taking a test, noting the result was interesting, and then takes more tests over the next few weeks, months, or years to confirm the results were something to be concerned about. If the tests are cheap and simple to run, there is no reason to EVER act on the basis of a single data point.