specificity

specificity /spec·i·fic·i·ty/ (spes″ĭ-fis´ĭ-te)

1. the quality or state of being specific.

2. the probability that a person who does not have a disease will be correctly identified by a clinical test.

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spec·i·fic·i·ty (sps-fs-t)

n.

1. The condition or state of being specific.

2. The statistical probability that an individual who does not have the particular disease being tested for will be correctly identified as negative, expressed as the proportion of true negative results to the total of true negative and false positive results.

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Specificity

A test's ability to detect only the disease in question.

Mentioned in: Tumor Markers

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specificity

[spes′əfis′itē]

Etymology: L, species, form, facere, to make

the quality of being distinctive. Kinds of specificity may include group, species, and type. See also diagnostic specificity.

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specificity

the quality of having a certain action, as of affecting only certain organisms or tissues, or reacting only with certain substances, as antibodies with certain antigens (antigen specificity).

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drug specificity

the degree to which the effects of a drug are due to the one pharmacological action.

host specificity

the restricted infectivity of a particular parasite to a certain species or group of hosts.

test specificity

the probability of a test correctly identifying those patients which are not infected or which do not have the specified condition. A fundamental parameter of any diagnostic test. See also sensitivity.

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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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specificity

Epidemiology The proportion of persons without disease who are correctly identified by a screening test or case definition as not having disease Immunology The avidity of an antibody for an antigen Physiology The degree of a ligand's affinity for a receptor

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Patient discussion about specificity.

Q. HIV - does it infect specific Blood Types? A friend of mine joined the army and they took him to an experiment and infected him with HIV. But he was not infected- he said because he has a certain blood type. Is this true?

A. I find it hard to believe the army infected any one with HIV. But that's a different story. Blood types differ from one another by their red blood cells proteins. HIV infects white blood cells .there is no connection between blood type and a cure for HIV. If there was- you’ve heard about it by now…

Q. Is Vitiligo caused due to any specific diet? Some people say that vitiligo is caused when we eat fish/chicken and curd together is it true??

A. Vitiligo (vit-ill-EYE-go) is a pigmentation disorder in which melanocytes (the cells that make pigment) in the skin are destroyed. As a result, white patches appear on the skin in different parts of the body. Similar patches also appear on both the mucous membranes (tissues that line the inside of the mouth and nose), and the retina (inner layer of the eyeball). The hair that grows on areas affected by vitiligo sometimes turns white. There is strong evidence that people with vitiligo inherit a group of three genes that make them susceptible to depigmentation. The most widely accepted view is that the depigmentation occurs because vitiligo is an autoimmune disease—a disease in which a person's immune system reacts against the body's own organs or tissues.

Q. What Causes Specific Abdominal Pain? Everytime I go see a doctor when I have abdominal pains he tells me I probably have gastroenteritis. How does he know that it's not something else for instance, appendicitis, just by examining my abdomen?

A. Abdominal pain is indeed caused by many different reasons, however some specific diseases or conditions cause specific location of pain. Upper abdominal pain that is located on the right, for instance, may suggests gall bladder problems, and on the left it could be a gastric ulcer. Lower abdominal pain on the right side could be appendicitis, and so on.