Gold standard (science)
- For other uses, see Gold standard (economics)
Gold standard refers to the best possible test to which all other tests can be compared. A common type of study in medical science compares a new diagnostic test to a "gold standard". This type of evidence is used to evaluate new methods of diagnosing disease as often the "gold standard" test may have the potential for complications or is expensive or time consuming.
For example, the gold standard for diagnosing pulmonary embolism (PE) is the pulmonary angiogram, in which dye is injected into the bloodtsream and xrays are taken of the arteries in the lungs. Because this is an invasive test, other methods of diagnosing the disease are desirable. Computed tomography (CT) scanning is an increasingly common method used to diagnose PE. To know how accurate it is, it must be compared to a test that is known to be good. Angiography is presumed to be nearly 100% sensitive and specific, and then CT can be compared to it, and its accuracy calculated.
Tests that are not a gold standard are presumed to contain a measure of error as the gold standard test is, for practical purposes, the most effective test available by definition (if a particular test was more effective than the gold standard, it would become the gold standard).