This chapter provides an overview of the most commonly used statistical tests in orthopedic sports medicine research. It starts by explaining the purposes of statistical testing and presenting foundational information on data types, descriptive measures, statistical significance, and the assessment of data distribution. Basic information on sample size calculation is also included. A distinction is made between statistical tests used to compare groups and those utilized to analyze associations between variables. Each category of tests is summarized in a structured table, indicating their objectives, main assumptions, and appropriate applications based on group types and data characteristics. Other tests, such as those used for the reliability assessment of measures, are also described. The chapter discusses the statistical input at different study phases, starting from the study protocol to reporting results. Finally, a glossary is provided to clarify terms related to statistical testing.