Objectives: To promote healthcare information exchange between providers and to allow hospital information systems (HIS) export information in standardized format (HL7 and DICOM) in an environment of widespread legacy systems, which only can export data in proprietary format.Methods: Through the Shizuoka prefecture EMR project in 2004-2005, followed by the ministry's SS-MIX project, many software products have been provided, which consist of 1) a standardized storage to receive HL7 v2.5 messages of patient demographics, prescription orders, laboratory results, and diagnostic disease in ICD-10, 2) a referral letter creation system, 3) a formatted document creation system, 4) a progress note/nursing record system, and 5) an archive/viewer to incorporate incoming healthcare data CD and allow users to view on HIS terminal. Meanwhile, other useful applications have been produced, such as adverse event reporting and clinical information retrieval. To achieve the above-mentioned objectives, these software products were created and propagated, because users can use these software products, provided that their HIS can export the above information to the standardized storage in HL7 v2.5 format.Results: In 20 hospitals of Japan, the standardized storage has been installed and some applications have been used. As major HIS vendors are shipping HIS with HL7 export function since 2007, HIS of 594 hospitals in Japan became capable of exporting data in HL7 v2.5 format (as of March 2010).Conclusions: In high CPOE installation rate (85% in 400+ bed hospitals), though most of them only capable of exporting data in proprietary format, prefecture and ministry projects were effective to promote healthcare information exchange between providers. The standardized storage became an infrastructure for many useful applications, and many hospitals started using them. Ministry designation of proposed healthcare standards was effective so as to allow vendors to conform their products, and users to install them.

Summary Objectives: This paper illustrates a high speed clinical data retrieving system, from 10 years of data of operating hospital information system for the purposes of research, evidence creation, patient safety, etc., even incorporating time sequence of causal relations. Methods: Total of 73,709,298 records of 10 years at Hamamatsu University Hospital (as of June 2008) are sent from HIS to retrieval system in HL7 v2.5 format. Hierarchical variable length database is used to install them. Results: A search for “listing patients who were prescribed Pravastatin (Mevalotin and generic drugs, any titer)” took 1.92 seconds. “Pravastatin (any) prescribed and recorded AST >150 within two weeks” took 112.22 seconds. Searching conditions can be set to be more complex, connected by Boolean operator and/or. This system called D*D is in operation at Hamamatsu University Hospital since August 2002. It is used for 48,518 times (monthly average of 703 searches). Neither searching, nor background export of data from HIS caused delay of routine operating CPOE. Conclusions: Search database outside of routine operating CPOE, with daily export of order data in HL7 v2.5 format, is proved to provide excellent search environment without causing trouble. Hierarchical representation gives high-speed search response, especially with time sequence of events.

Objectives: This paper illustrates a high speed clinical data retrieving system, from 10 years of data of operating hospital information system for the purposes of research, evidence creation, patient safety, etc., even incorporating time sequence of causal relations.Methods: Total of 73,709,298 records of 10 years at Hamamatsu University Hospital (as of June 2008) are sent from HIS to retrieval system in HL7 v2.5 format. Hierarchical variable length database is used to install them.Results: A search for "listing patients who were prescribed Pravastatin (Mevalotin and generic drugs, any titer)" took 1.92 seconds. "Pravastatin (any) prescribed and recorded AST > 150 within two weeks" took 112.22 seconds. Searching conditions can be set to be more complex, connected by Boolean operator and/or. This system called D*D is in operation at Hamamatsu University Hospital since August 2002. It is used for 48,518 times (monthly average of 703 searches). Neither searching, nor background export of data from HIS caused delay of routine operating CPOE.Conclusions: Search database outside of routine operating CPOE, with daily export of order data in HL7 v2.5 format, is proved to provide excellent search environment without causing trouble. Hierarchical representation gives high-speed search response, especially with time sequence of events.

Low cost image delivery is needed in modern networked hospitals. If a hospital has hundreds of clients, cost of client systems (hardware and software) is a big problem. Naturally, a Web-based system is the most effective solution. But a Web browser could not display medical images with certain image processing such as a lookup table transformation (e.g. VOI).We developed a Web-based medical image display system using Web browser and on-demand server-side image processing. All images displayed on a Web page are generated from DICOM files on a server, delivered on-demand. User interaction on the Web page is handled by a client-side scripting technology such as JavaScript. This combination makes a look-and-feel of an imaging workstation not only for its functionality but also for its speed. Real time update of images (zooming, window level/width change) with tracking mouse motion is achieved on Web browser without any client-side image processing which may be done by client-side plug-in technology such as Java Applets or ActiveX.We tested performance of the system in three cases. Single client, small number of clients in a fast speed network, and large number of clients in a normal speed network. The result shows that there are very slight overhead for communication and very scalable in number of clients.

To realize clinical data exchange between healthcare providers, there must be many standards in many layers. Terms and codes should be standardized, syntax to wrap the data must be mutually parsable, then transfer protocol or exchange media should be agreed. Among many standards for the syntax, HL7 and DICOM are most successful. However, everything could not be handled by HL7 solely. DICOM is good for radiology images, but, other clinical images are already handled by other "lighter" data formats like JPEG, TIFF. So, it is not realistic to use only one standard for every area of clinical information. For description of medical records, especially for narrative information, we created SGML DTD for medical information, called MML (Medical Markup Language). It is already implemented in more than 10 healthcare providers in Japan. As it is a hierarchical description of information, it is easily used as a basis of object request brokering. It is again not realistic to use MML solely for clinical information in various level of detail. Therefore, we proposed a guide-line for use of available medical standards to facilitate clinical information exchange between healthcare providers. It is called MERIT-9 (MEdical Records, Images, Texts,--Information eXchange). A typical use is HL7 files, DICOM files, referred from an MML file in a patient record, as external entities. Both MML and MERIT-9 are research projects of Japanese Ministry of Health and Welfare, and the purpose is to facilitate clinical data exchanges. They are becoming to be used in technical specifications for new hospital information systems in Japan.

At Hamamatsu University Hospital, an ATM + FDDI network was installed in January 1995, when the hospital information system was upgraded. With its unique 'wheel' shape configuration, FDDI automatically backs up in case of an ATM switch failure. The authors implemented a DICOM image database server and DICOM viewer in the Hamamatsu University Hospital ATM + FDDI network. The DICOM standard worked well between different vendor products. In sending 512 x 512, 2 byte CT images, 40% of the transfer time was spent for the network data transfer, which is 70% of the theoretical value of 10 Mb peripheral transfer rate. Meanwhile, ATM load factor increased less than 0.5%. As we have a very fast data transfer network, we must check display speed, hard disc access time, PC bus speed, and display software, in order to enjoy the high speed network transfer fully. The sequence of image transmission within a study is not stated in the DICOM document and is depending on the server. Therefore, there should be an agreement between server and clients, still more than DICOM, in order to make better PACS.

To realize clinical data exchange between healthcare providers, there must be many standards in many layers. Terms and codes should be standardized, syntax to wrap the data must be mutually parsable, then transfer protocol or exchange media should be agreed. Among many standards for the syntax, HL7 and DICOM are most successful. However, everything could not be handled by HL7 solely. DICOM is good for radiology images, but, other clinical images are already handled by other ‘lighter’ data formats like JPEG, TIFF. So, it is not realistic to use only one standard for every area of clinical information. For description of medical records, especially for narrative information, an standard generalized mark-up language, document type definition (SGML DTD) for medical information, called MML (medical markup language) had been created in Japan. It is already implemented in more than ten healthcare providers. However, it is again not realistic to use MML solely for clinical information in various level of detail. Therefore, we proposed a guideline for use of available medical standards to facilitate clinical information exchange between healthcare providers. It is called MERIT-9 (MEdical Records, Images, Texts, -Information eXchange). A typical use is HL7 messages, DICOM files, referred from an MML file in a patient record, as external entities. Both MML and MERIT-9 have been research projects of Japanese Ministry of Health and Welfare and the purpose is to facilitate clinical data exchanges. They are becoming to be used in technical specifications for new hospital information systems in Japan.

Recently, a DICOM-compliant image server application (Query/Retrieve Service Class Provider; Q/R SCP) is available commercially or freely in small or large scale. It is better to use these products as an image management sub system of sophisticated image networking applications such as a teaching file system and electric clinical patient record exchange. We describe a new facility to construct medical image database systems using Query/Retrieve Service Class applications. We propose a new Internet Standard; DICOM-QR URL scheme. It is an expansion of the URL (Uniform Resource Locator) standard to comply the DICOM standard. The DICOM-QR URL conveys the complete information to access to the specified images on the Q/R SCP. It is encoded into the compact ASCII string that is easily stored in fields of relational databases or text documents. Finally, we propose that the DICOM-QR URL scheme should be standardized following the Internet Standards Process and we propose many colleagues to join the process.

This paper proposes a new Internet standard that is combination of two standards in different domain Internet and medical informatics. The both standards are described briefly in this paper: We describe how to combine them into a Internet standard. With a new standard there are several advantages for medical information systems. The standard should be established by the following way of the Internet standards.