Retrospective database study is an important type of real world study that employ observational designs, which has received wide attention. However, misunderstandings and inappropriate conduct of retrospective database studies are very common. We systematically introduced the concept, features and applications of retrospective database study, as well as discussed the methods to plan a retrospective database study and how to develop a research database. This article is expected to offer guidance for the quality production and appropriate use of retrospective database study.
