This course will provide trainees with an overview of statistical methods and issues related to the design and analysis of observational studies. Course objectives are as follows: understand the value of observational study and the background for causal inference, design and write an analysis plan for an observational study, analyze data (using Stata software) with multiple regression analysis to adjust for confounders, review the literature related to large databases to motivate how future studies can be planned, and introduce the concept of meta-analysis for observational studies and their reporting standards.