Diagnostic test

In medicine, a diagnostic test is any kind of medical test performed to aid in the diagnosis or detection of disease, injury or any other medical condition. For example, such a test may be used to confirm that a person is free from disease, or to fully diagnose a disease, including to sub-classify it regarding severity and susceptibility to treatment. Companion diagnostics have also been developed to preselect patients for specific treatments based on their own biology, where such targeted therapy may hold promise in personalized treatment of diseases such as cancer.

A drug test can be a specific medical test to ascertain the presence of a certain drug in the body (for example, in drug addicts).

Overview

Most diagnostic tests are conducted on the living; however, some of these tests can also be carried out on a dead person as part of an autopsy. Some of the diagnostic tests are parts of a simple physical examination which require only simple tools in the hands of a skilled practitioner, and can be performed in an office environment. Some other tests require elaborate equipment used by medical technologists or the use of a sterile operating theatre environment. Some tests require samples of tissue or body fluids to be sent off to a pathology lab for further analysis. Some simple chemical tests, such as urine pH, can be measured directly in the doctor's office.