False-positive

Test or procedure result indicating a positive or abnormal result when, in fact, no abnormal condition is actually present. A specific test has a low false-positive rate. A non-specific test has a high false-positive rate and should not be relied upon to suspect or diagnose an abnormality or disease. Some types of urine pregnancy tests are very nonspecific - any type of contaminant (such as dirt, blood, or vaginal secretions) may give a false-positive result when, in reality, the patient is not pregnant. A serum pregnancy test is both sensitive and specific.