Which doesn&#x27;t mean it&#x27;s not a good test to rule out the tested condition if there are symptoms that might indicate the condition. Sometimes it&#x27;s clinically valuable to rule out a condition, particularly if the appropriate treatment for another possible condition would be drifter if the tested-for condition might be present. There are people whose training makes them, in principle, the appropriate experts to decide when these tests are needed and worthwhile, they&#x27;re called physicians.