How to evaluate a diagnostic test

Tests are used in dentistry to establish, confirm, or reject the clinical i mpression of a diagnosis. Not all tests are equal in their ability to estab lish a diagnosis, with some tests demonstrating positive results when no di sease is present (false positive) or negative results when disease is prese nt (false negative). Using simple mathematical computations, it is possible to determine the extent to which a test can reliably establish the presenc e or absence of disease. This article describes the concepts of sensitivity , specificity; positive predictive value, negative predictive value, and li kelihood ratios through the evaluation of a clinically relevant paper on vi tal staining for oral carcinoma. This article also describes methods for li terature evaluation to determine whether a test conveys meaningful diagnost ic information.