Evaluation of Various Database Architectures for Datawarehouses: a Case Study on ETL integrated EHR

EHR (Electronic Health Records) describing the diseases and treatments of patients are normally stored in the hospital locations or regions, where they are created. However, patients may be treated in different hospitals, and therefore, there is a need for integrating health records from different hospitals to enable any hospital to obtain a total overview of a patient's health-history. Two different types of heterogeneity problem have to be solved in order to integrate EHR systems from different hospitals in a consistent way. The first problem is that different hospitals normally do not use a common DBMS (Data Base Management System) system and therefore, the traditional ACID (Atomicity, Consistency, Isolation and Durability) properties are missing across the different hospital locations. The second heterogeneity problem is that there are different incompatible standards on how to make EHR registrations. The objective of this paper is to describe and evaluate different EHR database designs for storing more or less incompatible health records from different hospitals.