Overview of North American Databases

Large electronic health databases provide cost-effective and efficient means for conducting postmarketing surveillance studies. These databases are suitable for research because they consist of claims or medical records of inpatient and outpatient care, including emergency care, laboratory and radiological tests, and prescription medications, sometimes from well-defined populations with a long history. Other useful features are their use of unique patient identifiers to allow linking various parts of the database and allow tracking across enrollment periods, ability to access the original medical charts to conduct reviews to confirm outcomes, use of standard coding for recording diagnoses, procedures, and drugs, and, importantly, regular updates and quality control checks of the records. All study designs available to pharmacoepidemiologic research can be applied to these databases, including simulated clinical trials. This chapter reviews as examples several databases in North America that have been used extensively for pharmacoepidemiologic research.