In the recent years, advances in different fields of technology have been resulted in a dramatic increase in the diagnostic methods and tests in different branches of clinical medicine with a consequent increase in the number of scientific publications related to the application of those tests and methods in the diagnosis or prevention of diseases. Dermatology is not an exception. Since, evidence-based medicine emphasizes on the appropriate use of the current best clinical research evidence in the diagnosis or treatment of each individual patient acknowledging his/her values, the capability of dermatologists in appraisal and application of the publications, which reports the results of diagnostic test accuracy studies cannot be ignored. In this article, after a brief review on basic issues in diagnostic test accuracy studies, principles of critical appraisal of these studies, from an evidence-based viewpoint, will be discussed. General strategies for evaluation of validity, applicability and quality assessment of a diagnostic test study will be provided.