[Testing, estimating, "significance"--concepts and terminology of medical biometry].

The justification for the application of medical treatments and diagnostic methods has gained importance during the last decades. Together with scientific argumentations also the concepts of medical statistics have found a wide-spread use and are nowadays indispensible tools for clinical research. In publications of clinical trials, epidemiological investigations and animal experiments p-values, statistical tests and confidence intervals help the reader to evaluate the significance and relevance of the provided results. A prerequisite is a clear understanding of the concepts underlying these methodological terms. This paper presents the basic concepts of medical statistics and demonstrates the conclusions that can be drawn with the aid of these concepts.