Establishing semantic interoperability in the course of clinical document exchange using international standard for metadata registry

Around the world electronic health records data are being shared and exchanged between two different systems for direct patient care, as well as for research, reimbursement, quality assurance, epidemiology, public health, and policy development. It is important to communicate the semantic meaning of the clinical data when exchanging electronic health records data. In order to achieve semantic interoperability of clinical data, it is important not only to specify clinical entries and documents and the structure of data in electronic health records, but also to use clinical terminology to describe clinical data. There are three types of clinical terminology: interface terminology to support a user-friendly structured data entry; reference terminology to store, retrieve, and analyze clinical data; and classification to aggregate clinical data for secondary use. In order to use electronic health records data in an efficient way, healthcare providers first need to record clinical content using a systematic and controlled interface terminology, then clinical content needs to be stored with reference terminology in a clinical data repository or data warehouse, and finally, the clinical content can be converted into a classification for reimbursement and statistical reporting. For electronic health records data collected at the point of care to be used for secondary purposes, it is necessary to map reference terminology with interface terminology and classification. It is necessary to adopt clinical terminology in electronic health records systems to ensure a high level of semantic interoperability.

Toward the Automatic Generation of the Entry Level CDA Documents / 대한의료정보학회지

OBJECTIVE: CDA (Clinical Document Architecture) is a markup standard for clinical document exchange. In order to increase the semantic interoperability of documents exchange, the clinical statements in the narrative blocks should be encoded with code values. Natural language processing (NLP) is required in order to transform the narrative blocks into the coded elements in the level 3 CDA documents. In this paper, we evaluate the accuracy of text mapping methods which are based on NLP. METHODS: We analyzed about one thousand discharge summaries to know their characteristics and focused the syntactic patterns of the diagnostic sections in the discharge summaries. According to the patterns, different rules were applied for matching code values of Systematized Nomenclature of Medicine Clinical Terms (SNOMED CT). RESULTS: The accuracy of matching was evaluated using five-hundred discharge summaries. The precision was as follows: 86.5% for diagnosis, 61.8% for chief complaint, 62.7%, for problem list, and 64.8% for discharge medication. CONCLUSION: The text processing method based on the pattern analysis of a clinical statement can be effectively used for generating CDA entries.

CDA Compression via Automatic Type Inference / 대한의료정보학회지

OBJECTIVE: CDA is a standard for the exchange and sharing of clinical documents among all entities in the healthcare domain. As it proliferates, the number of CDA documents will increase exponentially and it will require huge storage spaces to store them. The main goal of this study is to devise an efficient compression method optimized for CDA documents so that the storage requirement can be lowered. METHODS: The method proposed in this paper is based on a compression method called Xmill which has been designed specifically for XML documents at large, which requires human intervention for the effective compression, especially, of CDA. Our proposed method, CDACOM, automatically extracts type information from CDA documents to infer the data type, assigns data values of the same type to the same data container, and applies an optimized encoder to the container so that a better compression rate can be achieved. RESULTS: Experiments with various types of CDA documents were performed to evaluate the effectiveness of CDACOM over Xmill. The results show that CDACOM indeed outperforms Xmill and can decrease the output file size by about 24.1% on average, compared to Xmill. If documents are combined and compressed together, the gap gets even bigger to about 50%. CONCLUSION: The proposed compression method, CDACOM, is very effective and promising. It will help lowering the cost for systems to transmit and store CDA documents and, hence, expediting the adoption of the standard in the healthcare domain.

The Interchange of Radiological Reports Using Clinical Document Architecture Standards / 대한의료정보학회지

OBJECTIVE: We developed a Clinical Document Architecture(CDA) Generator module based on CDA standard for the interchange of radiological reports. METHODS: This paper describes CDA standard, the template of radiological report, CDA Generator module, and the Web-form report using an Extensible Stylesheet Language(XSL) style-sheet. And the CDA Generator module is integrated into a existing Picture Archiving Communication System(PACS) Viewer. RESULTS: Radiological reports based on CDA standard are used to interchange between different health institutions, and also presented in an Extensible Markup Language (XML) compatible web browser. CONCLUSION: The proposed module and concept in this paper may be a utility in improving health care delivery and can also be used to integrate with other Digital Imaging and Communication in Medicine(DICOM) Structured Report (SR) compliant PACS systems.

Clinical Document Repository System for Electronic Health Record / 대한의료정보학회지

OBJECTIVE: The needs of sharing clinical documents in order for health professionals to provide better diagnosis and treatment have been tremendously increasing. However, when a patient visits the hospital, current hospital information system doesn't allow for physicians to obtain patient's medical history even though she has some records in different hospital, because the lack of the standardization to overcome the incompatibility among heterogeneous systems. CDA(Clinical Document Architecture) of HL7(Health Level 7) is standardized technology in purpose of creating and exchanging various clinical documents. In this article, we discuss the method of exchanging, storing, and utilizing CDA and present the work of development and implementation based on CDR(Clinical Document Repository) framework reported earlier9). METHODS: We convert paper-based discharge summary from each health institutions into CDA format. And in order to exchange, manage, and utilize those CDA, Registry structure of ebXML is introduced and applied. RESULTS: The relationship among patients, physicians, clinical organizations, and clinical documents is well-organized and modeled. Because transfered CDA document can be easily registered and managed by complying with RIM structure of ebXML, this system can effectively exchange and share patient's CDA document when patient move to other area or among heterogenous systems. CONCLUSION: This system can be utilized to categorize and store various clinical documents such as, ECG and Radiology reading report. In addition, this system suggests the potential of Electronic Health Record system that is able to communicate among heterogenous systems and manage the CDA documents via this CDR system.

Presentation of Structural Constraints for Discharge Note According to Clinical Document Architecture Standard / 대한의료정보학회지

OBJECTIVE: HL7(Health Level 7) develops standards for the representation of clinical documents like discharge and consultation notes. The goal of the present study is to develop XML(eXtensible Markup Language)-based communication standard for discharge note. METHODS: This paper presents the use of XML for electronic communication in a document-based EMR, first, as a format for the exchange of structured message, and second, as a comprehensible way to represent patient document. A retrospective analysis of 1165 discharge notes, from the department Seoul National University Hospital, were extracted by querying OCS(Order Communication System) and taking every discharge note of main disease issued over one year period (2003.01.01~2003.12.31). RESULTS: An XML-based prototype for discharge note has been put into place representing the required "section" and "specific instance". In addition, a subset of the CDA(Clinical Document Architecture) Level One details has been described and integrated. CONCLUSION: Through the introduction of definitions for sections and specific instances, progress in the development of CDA Level Two and Three might be realized. An XML-based prototype was implemented, allowing a special view on XML data to generate this document type.

Realization of data access to clinical information for cross-hospital patients / 医疗卫生装备

One important problem of regional information system in healthcare is the access to electronic patient records across healthcare institute boundaries. The Integrating Healthcare Enterprise initiatively proposes the integration profile of the retrieve information for display that enables a user to retrieve and display patients' related documents cross hospitals. The middleware is added to HIS to realize the cross-hospital data access to clinical information with access authorization and privacy regulations. Besides,the integration of cross-hospital patients' clinical information is achieved based on the realization of Patient ID protocol in different systems.