课程介绍：Epidemiology is not only a major subject of public health, but also a fundamental subject of modern medicine. It is a discipline that aims to identify the distribution and determinants of health-related states or events in specified populations, and the application of this study to control health problems. Epidemiologic methods were first used to prevent diseases like cholera and measles; today it is used to study genetic, behavioral, and environmental causes of infectious and non-infectious diseases. Epidemiologic methods are used to evaluate the effect of treatments or screening and it is the key subject in the development of “evidence based medicine”. This course will provide the basic principle and knowledge about the most common types of epidemiologic studies, how they are used, what kinds of bias they may caused and their limitations. We then provided examples of how these methods have been used in public health and clinical research. Although each method has their own characteristics, most methods rely on the same basic set of logical reason. The statistical part of analyzing data was left out; students could read many textbooks on this topic. This section is short and condensed, but students in medical science are trained in absorbing information rapidly. Epidemiology is training in logical thinking rather in memorization and we hope this course will be a pleasant journal into a mindset for later expansion and use.