In medicine, a gold standard test is the diagnostic test that is regarded as definitive in determining whether an individual has a disease process. The AMA Style Guide prefers the phrase Criterion Standard instead of Gold Standard, and many medical journals now mandate this usage in their instructions for contributors. For instance, Archives of Physical Medicine and Rehabilitation specifies this usage [1]. Medicine is a branch of health science and the sector of public life concerned with maintaining or restoring human health through the study, diagnosis, treatment and possible prevention of disease and injury. ... Diagnosis (from the Greek words dia = by and gnosis = knowledge) is the process of identifying a disease by its signs, symptoms and results of various diagnostic procedures. ...

A hypothetical ideal gold standard test has a sensitivity of 100% (it identifies all individuals with a disease process; it does not have any false-negative results) and a specificity of 100% (it does not falsely identify someone with a condition that does not have the condition; it does not have any false-positive results). In practice, there are no ideal gold standard tests. The sensitivity of a binary classification test or algorithm, such as a blood test to determine if a person has a certain disease, or an automated system to detect faulty products in a factory, is a parameter that expresses something about the tests performance. ... The specificity of a binary classification test with respect to a given class is the probability that the test correctly classifies case not belonging to that class. ...

Because tests can be incorrect (either a false-negative or a false-positive result), results should be interpreted in the context of the history, physical findings, and other test results in the individual that is being tested. It is within this context that the sensitivity and specificity of the gold standard test is determined. Scientists recognize two different sorts of error:[1] Statistical error: the difference between a computed, estimated, or measured value and the true, specified, or theoretically correct value (see errors and residuals in statistics) that is caused by random, and inherently unpredictable fluctuations in the measurement apparatus. ... Scientists recognize two different sorts of error:[1] Statistical error: the difference between a computed, estimated, or measured value and the true, specified, or theoretically correct value (see errors and residuals in statistics) that is caused by random, and inherently unpredictable fluctuations in the measurement apparatus. ...

Quite often the gold standard test is not the test performed in a particular individual. In fact, many gold standard tests are not performed in the clinical practice of medicine at all. This is because the gold standard test may be difficult to perform or may be impossible to perform on a living person (i.e. the test is performed as part of an autopsy), or may take too long for the results of the test to be available to be clinically useful. The Anatomy Lesson of Dr. Nicolaes Tulp, by Rembrandt, depicts an autopsy An autopsy, also known as a post-mortem examination or an obduction, is a medical procedure that consists of a thorough examination of a human corpse to determine the cause and manner of a persons death and...

As new diagnostic methods become available, the gold standard test may change over time. For instance, for the diagnosis of aortic dissection, the gold standard test used to be the aortogram, which had a sensitivity as low as 83% and a specificity as low as 87%. Since the advancements of magnetic resonance imaging, the magnetic resonance angiogram (MRA) has become the new gold standard test for aortic dissection, with a sensitivity of 95% and a specificity of 92%. Before widespread acceptance of any new test, the former test retains its status as the gold standard. Aortic dissection is a tear in the wall of the aorta (the largest artery of the body). ... This article or section does not cite its references or sources. ...