- A screening test is a simple test used to detect the presence of disease in individuals in a defined population. An example is measuring the level of TSH in blood obtained from a newborn infant as part of newborn screening for congenital hypothyroidism.
- A diagnostic test disease is a procedure performed to confirm the presence of disease in an individual suspected of having the disease. An example is measuring the blood sugar in a person suspected of having diabetes mellitus because of increased urination.
- A test may be performed to monitor the progress of, or response to medical treatment, of a disease. An example is a measurement of forced expiratory volume to assess response to treatment of asthma.
- A test may aid in determining the likely future course (prognosis) of a disease. An example is a biopsy of a removed tumor to determine the degree of malignancy.
- A test may be performed to confirm that a person is free from disease. An example is a thyroid scan performed after surgery to remove thyroid cancer.