: a person or test result that is incorrectly classified as positive (as for the presence of a health condition) because of imperfect testing methods or procedures
A false positive—a test result indicative of disease that isn't actually present—can trigger a chain reaction of worry, further tests, and even unnecessary treatment.Harvard Health Letter
The quarantine could be lifted early if the lab confirms that the case was a false positive. Kathleen Moore
Perhaps more important, polygraph tests are notoriously unreliable. Scientists are understandably concerned about false positive results …Chemical & Engineering News
—often hyphenated when used before another noun
The technology could improve a radiologist's ability to detect breast cancers and it could lower the number of false-positive results … Laurie Tarken