This is the first in a series of articles that provide a guide to the
understanding and effective use of diagnostic tests in clinical and
research endeavors. In this article, we briefly describe some general
properties of diagnostic tests. We then focus our attention on binary
diagnostic tests, i.e., tests that have only two outcomes, positive or
negative. Even though most medical literature assumes that all diagnostic
tests are binary, truly binary tests are actually quite rare. Studying
them, however, provides a convenient way to familiarize ourselves with
important decision-making nomenclature.Abstract Teaser