[The basic ideas for evaluating diagnostic tests in medicine and periodontics].

In the medical literature, and in particular in the field of periodontology, one could observe since several years an increasing interest in diagnostic tests. However, these are often difficult to comprehend. Indeed, understanding the value of these tests implies mastering the meaning of certain basic notions such as sensitivity, specificity and predictive value. The aim of this paper is to present these essential theoretical notions in a simple way and to illustrate them using clinical examples. Finally, several applications of these tests in the field of periodontology will be discussed.