Diagnostic testing in family practice.

Laboratory and radiological investigations are central to the diagnosis and management of our patients' health problems. Physicians often order a diagnostic test routinely without giving much thought to the benefits, risks, and costs of the test. The increase in the number and use of diagnostic tests has contributed to the rising cost of health care over the last two decades. By consciously following a process when ordering tests, physicians may improve the effectiveness and efficiency of the tests they request. This paper provides a background and approach to the rational use of diagnostic tests.