This course is designed to develop skills necessary in the critical appraisal of pharmacoepidemiological studies with a particular focus on advanced methodological issues, study design, analysis, and interpretation of results. It includes methods for quantifying drug utilization and a discussion of the most common statistical models used in assessing the risks and benefits associated with drug use. The course will cover cohort, case-control, nested case-control, and within-subject designs, along with various sources of information and selection bias. These issues will be addressed through a review of several published pharmacoepidemiological studies, focusing particularly on studies using computerized health databases.