Abstract: The impact of proper statistical method selection on the credibility of medical research results is obvious. Naturally, there are many articles and works on how to properly select statistical methods in medical research. However, the misuse of statistical analysis methods in Chinese medical journals is still common. The reasons may be complex, but excessive pursuit of the use of specific methods and insufficient understanding of their basic concepts may be one of the important reasons for the misuse of statistical methods. This article will focus on the two important concepts of design types and variable types involved in the design phase, and discuss the key points to choose appropriate statistical methods. The aim is to improve the scientific and statistical quality of medical papers.