Strategies to Access Patient Clinical Data from Distributed Databases

Over the last twenty years, the use of electronic health record systems has become widespread worldwide, leading to the creation of an extensive collection of health databases. These databases can be used to speed up and reduce the cost of health research studies, which are essential for the advance of health science and the improvement of health services. However, despite the recognised gain of data sharing, database owners remain reluctant to grant access to the contents of their databases because of privacy and security issues, and because of the lack of a common strategy for data sharing. Two main approaches have been used to perform distributed queries while maintaining all data control in the hands of the data custodians: applying a common data model, or using Semantic Web principles. This paper presents a comparison of these two approaches by evaluating them according to parameters relevant to data integration, such as cost, data quality, interoperability, extendibility, consistency, and efficiency.