1. Architecture of Gil Hospital Information System
The information system of Gachon University Gil hospital consists of OCS, electronic medical record (EMR) system, picture archiving and communication system (PACS), enterprise resource planning (ERP) system, data warehousing (DW) system and web system.
Hospital information system should collect, manage and use enormous quantity of data.
Figure 1 is overall architecture of the information system for Gachon University Gil hospital. The information system of Gachon University Gil hospital is connected organically. So the data, which is created in the administration, is collected at the final destination, ERP and DW, and the group ware has been built to assist decision making.
Figure 2 is the hardware architecture of Gil hospital information system. The system of OCS and EMR consist of database application and file server. The database server is dualized by coupling Unix OS and Sybase database on the IBM AIX (HACMP), the application server and file server are based on Microsoft Windows which are dualized (Microsoft cluster service, MSCS).
The ERP system uses OracleR11i package, and the operation server consists of Unix OS and Oracle DB on the IBM AIX server so that the database and application are operated on the identical server.
The DW system consists of data storage enterprise application integration (EAI) tool, Business Objects OLAP tool, and Oracle database. The DW server consists of Unix OS on the IBM AIX and the Business Objects have been built for Windows.
PACS system consists of database, storage, and application and the dataset server has been built on the IBM AIX using Oracle. The storage consists of IBM NS6040 (NAS) and the application has been integrated on the BladeCenter in Windows circumstance.
Web system also uses Windows server. The Web Server mainly consists of internet information server (IIS) and database consists of Microsoft structured query language (MS-SQL), and both of them are integrated on the BladeCenter to save the space and cost.
The software for Gachon University Gil hospital information system has been built considering characteristics of each work. Like hardware system, the software system has been also divided in the OCS, EMR service, PACS service and Web service, and its construct has been shown for each of works.
The EMR system consists of three tiers. The database uses Sybase, the application consists of COM+ of .Net Framework and ADO.Net, and the user interface has been developed by Win Forms on the .Net Framework.
The OCS system consists of two tiers. The database uses Sybase, the Business logic mainly processes by stored procedure and the user interface has been developed using Visual Basic.
The ERP system consists of three tiers. The database is based on Oracle and Oracle application R11i package provides business logic process and user interface.
The PACS system consists of two tiers. The data based is based on Oracle and the user interface has been developed by C++ and uses the network access server (NAS) storage.
The Web system consists of three tiers. The system circumstance differs by characteristics of each work but database for most of systems is based on the MS-SQL. The Web server uses IIS and the user interface has been developed by the active server page (ASP).
The most important evaluation index for hospital information system management is system operation rate. The hospital has very special work condition that must be operated for 365 days in a year without a break, because of the special characteristic of its work. Because of this trend of system, OCS, EMR system, PACS, and network operation rate are important items for medical service evaluation at a hospital.
Figure 3 shows software architecture of Gil hospital's information system.
2. Characteristics of Gachon University Gil Hospital's Hospital Information System
Gachon University Gil hospital integrated its data through digital hospital project. Digital hospital project was started in 2004 through 2005 in cooperation with MCC and Oracle. Objectives of digital hospital project was to establish ERP and DW that include financial accounting (FI), supply chain management (SCM), activity based management (ABM), balanced score card (BSC) and data integrations between systems were essential task.
Cash recipients system was needed to convert to accrual accounting in accountancy system for data integration. Data alteration management system was applied to OCS and EMR data to establish occurrence base system. Data alteration management system creates one record of data, two altered data and one delete data per occurrence date. Data alteration management reduces ERP and DW system load by stacking only end date data.
Data integration was done in five phases. Data alteration management and distributed financial processing settlement management of accounts were applied in the first step. Enterprise data warehousing (EDW), which previous data and new data created through data cleansing by data alteration management were established in the second phase. Data interface were established in the third stage by establishing data mart (DM) per subject category, ERP SCM and FI module for on data in EDW.
By establishing ERP, pre-management system were established by providing financial information timely, which enables efficient fund management by occurrence based daily profit management and fund forecast by planning income and expenditure.