How to evaluate a diagnostic test.

Tests are used in dentistry to establish, confirm, or reject the clinical impression of a diagnosis. Not all tests are equal in their ability to establish a diagnosis, with some tests demonstrating positive results when no disease is present (false positive) or negative results when disease is present (false negative). Using simple mathematical computations, it is possible to determine the extent to which a test can reliably establish the presence or absence of disease. This article describes the concepts of sensitivity, specificity, positive predictive value, negative predictive value, and likelihood ratios through the evaluation of a clinically relevant paper on vital staining for oral carcinoma. This article also describes methods for literature evaluation to determine whether a test conveys meaningful diagnostic information.