Fifteen-minute consultation: How good is this test.

As technology evolves and cultural attitudes towards diagnosis change, there is an increasing move towards newer, faster and more accurate diagnostic testing. As new tests are developed, clinicians are increasingly required to appraise data from diagnostic test accuracy (DTA) studies.The accuracy of a test is fluid and changes depending on the population, setting, timing and position within the diagnostic pathway. This article attempts to provide a short guide to understanding diagnostic test accuracy and a simple approach to appraising DTA studies.