Evaluating medical tests

In this chapter, the authors consider various sorts of medical tests, and briefly introduce the types of test technology most commonly encountered in medical care and the research literature. They then review the multiple purposes for which medical tests are used and identify those that can be evaluated using the test accuracy paradigm and that therefore can be included in Cochrane Reviews of diagnostic test accuracy. Test accuracy studies evaluate the ability of a test to correctly classify study participants, based on the test results, as having the target condition or not. Cochrane Reviews of diagnostic test accuracy can provide evidence of the accuracy of a test, but often need to be used alongside other evidence to make a holistic judgement of the likely impact on patients. Evaluations of the accuracy of a medical test or procedure can be performed during various stages of the development of a medical test.