This course provides students who have completed EP813 with an opportunity to apply epidemiologic concepts to the analysis of observational datasets. Students learn strategies for building epidemiologic regression models using SAS software and examine key issues with respect to exposure, such as classifying time-varying exposures and comparing what is measured to biologically relevant. Also, the course emphasizes appropriate interpretation of results given a study's specific design, limitation, and potential epidemiologic biases. BS852 complements this course and may be taken concurrently. This course should be taken before EP817.