In medicine

Medicine

Medicine is the science and art of healing. It encompasses a variety of health care practices evolved to maintain and restore health by the prevention and treatment of illness....

, an indication is a valid reason to use a certain test, medication, procedure, or surgery. The opposite of indication is contraindication

Contraindication

In medicine, a contraindication is a condition or factor that serves as a reason to withhold a certain medical treatment.Some contraindications are absolute, meaning that there are no reasonable circumstances for undertaking a course of action...

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Drugs

In the United States, indications for medications are strictly regulated by the Food and Drug Administration (FDA), which includes them in the package insert

Package insert

A package insert or prescribing information is a document provided along with a prescription medication to provide additional information about that drug.-Responsible agencies:In the United States, the Food and Drug Administration determines the requirements...

 under the phrase "Indications and Usage". Most countries and jurisdictions have a licensing body whose duty it is to determine whether to approve a drug for a specific indication, based on the relative safety of the drug and its efficacy for the particular usage being investigated. The EMA

European Medicines Agency

The European Medicines Agency is a European agency for the evaluation of medicinal products. From 1995 to 2004, the European Medicines Agency was known as European Agency for the Evaluation of Medicinal Products.Roughly parallel to the U.S...

 holds this responsibility for the whole of the European Union

European Union

The European Union is an economic and political union of 27 independent member states which are located primarily in Europe. The EU traces its origins from the European Coal and Steel Community and the European Economic Community , formed by six countries in 1958...

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If a drug is prescribed or taken outstanding to its applied indications, such use is termed off-label

Off-label use

Off-label use is the practice of prescribing pharmaceuticals for an unapproved indication or in an unapproved age group, unapproved dose or unapproved form of administration...

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There are different classes of indication of drugs depending on validity of the benefit gained by the use of specific drug. As the consensus to use the drug increases its class of indication is improved.

Medical tests

Each test has its own indications and contraindications, but in a simplified fashion, how much a test is indicated for an individual depends largely on its net benefit for that individual, which largely depends on the absolute difference between pre- and posttest probability of conditions (such as diseases) that the test is expected to achieve. Additional factors that influence a decision whether a medical test should be performed or not include: cost of the test, time taken for the test or other practical or administrative aspects. The possible benefits of a diagnostic test may also be weighed against the costs of unnecessary tests and resulting unnecessary follow-up and possibly even unnecessary treatment of incidental findings. Also, even if not beneficial for the individual being tested, the results may be useful for the establishment of statistics in order to improve health care for other individuals.