false positive

false positive

n.

A positive test result in a subject that does not possess the attribute for which the test is being conducted.

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false-pos·i·tive adj.

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False positive

Test results showing a problem when one does not exist.

Mentioned in: Stress Test

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false positive,

a test result that wrongly indicates the presence of a disease or other condition the test is designed to reveal. Compare false negative.

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false

said of diseases or plants that have a superficial resemblance to another plant or disease.

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false acacia

see robinia pseudoacacia.

false blackleg

cellulitis and myositis caused by Clostridium septicum and C. novyi. More commonly called malignant edema. Characterized by high fever, severe toxemia and local swelling around a wound with subsequent local gangrene and a high mortality rate.

false blusher

see amanitapantherina—a mushroom.

false buckbush

see gyrostemonaustralasicus.

false bursa

see hygroma.

false castor oil plant

daturastramonium, D. ferox.

false columnaris disease

similar to columnaris disease but caused by infection with the bacteria Cytophaga johnsonae. Characterized by skin erosion especially at the fins and jaws.

false distemper

a disease of horses with some similarity to strangles. See pectoral abscess.

false garlic

alliumvineale.

false gid

see oestrusovis.

false hellebore

veratrumcalifornicum, V. viride.

false indigo

see baptisia leucantha.

false joint

a fracture in a long bone that does not heal; the ends callus over and there is mobility at the point.

false layer

a hen with all the appearances and the behavior of a laying hen but which does not lay any eggs. There is a defect in ovum entrapment and the eggs are discharged into the peritoneal cavity although egg peritonitis is not apparent.

false lupine

thermopsismontana, T. rhombifolia.

false negative

when the result of a test in a patient is negative when the disease or condition which is the subject of the search is present.

false positive

see false-positive.

false quarter

a condition of the horse's hoof in which a serious injury to the coronet causes an overgrowth of horn which overlaps the normal wall.

false scorpions

members of the order Pseudoscorpiones. Nonvenomous arachnids called also book scorpions.

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specificity 

The extent to which a test gives results that are free from false positives (i.e. people found to have the defect when they are actually free of it). The fewer the number of false positives, the greater is the specificity of the test. It is usually presented as the percentage of people truly identified as not defectives, or normal, referred to as true negatives, D (or correct reject), divided by the total number of not defectives or normal people tested. The total number includes all the true negatives, D, plus the false positives, B (or false alarm). Hence

See sensitivity.

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false positive

Lab medicine A test result from a Pt who does not have a particular disease, which is positive or detects an analyte that is usually normal. See Four cell diagnostic matrix, Cf False negative.