Encounter databases

Encounter databases contain electronic records of healthcare encounters for large, defined populations. They capture information on patient characteristics, prescription fills, and medical services, as part of the routine administration or reimbursement of healthcare. Encounter databases exist in many countries and within a number of vastly different healthcare systems; an increasing number is becoming available for research. Although they vary markedly in their specific characteristics, encounter databases share a number of defining features that warrant their discussion as a group. This chapter provides a description of key commonalities and distinctions across encounter databases, illustrated with selected examples and supplemented by references to more comprehensive resources in the literature. This is followed by a discussion of the strengths and weaknesses of encounter databases and the considerations faced by researchers when they evaluate the suitability of a specific encounter database for a given research question or face a choice among multiple encounter databases.