6th International Policy and Research                                        Conference on Social Security                ...
www.issa.int   4 route des Morillons               Case Postale 1               CH-1211 Geneva 22The International Social ...
Towards an e-health Integration Platform to Support               Social Security Services                        Laura Go...
implemented in the most rational way, trying to leverage the existing or future assets inthe involved organizations. [2]On...
of organizations that wish to exchange information and may have different internalstructures and processes.The development...
interoperability and flexibility by converting monolithic and static systems into modularand flexible components, represen...
Additionally, Integrating the Health Enterprise (IHE) [25] is an initiative driven byhealthcare professionals and industry...
Figure 1 - Semantic Web Standard Stack [34]The eXtensible Markup Language (XML) constitutes a syntactic base for the rest ...
The integration platform is proposed in the context of a SOA and integrates thecapabilities of ESBs, ontologies and Semant...
The solution proposes using an Enterprise Service Bus (ESB) and extending it withhealth specific capabilities. For example...
Based on this analysis, solution approaches were proposed in order to integrateadvanced middleware and semantic technologi...
[16] OpenEHR. http://www.openehr.org/ [Accessed: July 2010][17] Health Level Seven International (HL7). http://www.hl7.org...
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Towards an e health integration platform to support social security services

  1. 1. 6th International Policy and Research Conference on Social Security Emerging trends in times of instability: New challenges and opportunities for social securityLuxembourg, 29.9–1.10.2010Towards an e-health integration platform to supportsocial security servicesLaura González, Guzmán Llambías, Pablo PazosUniversidad de la República del UruguayUruguay
  2. 2. www.issa.int 4 route des Morillons Case Postale 1 CH-1211 Geneva 22The International Social Security Association (ISSA) is the worlds leading international organization bringingtogether national social security administrations and agencies. The ISSA provides information, research,expert advice and platforms for members to build and promote dynamic social security systems and policyworldwide.The view and opinions expressed here do not necessarily reflect those of the ISSA. © International Social Security Association, 2010.
  3. 3. Towards an e-health Integration Platform to Support Social Security Services Laura González, Guzmán Llambías, Pablo Pazos Laboratorio de Integración de Sistemas, Instituto de Computación, Facultad de Ingeniería, Universidad de la República del Uruguay. Julio Herrera y Reissig 565, CP 11300, Montevideo, Uruguay. {lauragon, gllambi}@fing.edu.uy, pablo.swp@gmail.com AbstractNowadays, health services are increasingly related to social security systems. In manycountries, either health benefits are part of social security programmes or they areassociated to the rights of certain population (e.g. workers and their families). Suchrelations generate interactions between the health and social security implementations,especially when they are based on Information and Communication Technology (ICT)systems.The automation of these interactions presents various benefits like the possibility toshare and combine facilities and information, in order to provide value added socialsecurity services. Various standards have been proposed to support these interactionsin an interoperable way, while leveraging the ICT assets within the interactingorganizations.However, health actors usually adopt specific information representation standards (e.g.HL7), which normally differs from the ones used by social security organizations.Moreover, standards constantly evolve which present various challenges in terms offlexibility, adaptability and interoperability.This paper analyzes these issues and proposes solution approaches based onmiddleware and semantic technologies. The paper focuses on interoperability issuesand how the facilities provided by advanced middleware and semantic technologies, likeEnterprise Service Bus and Semantic Web Services respectively, can assist in resolvingthem. The solutions were analyzed, implemented and evaluated in the context of areference architecture based on service oriented principles. The work presented in thispaper constitute a starting point towards building an e-health integration platform, inwhich social security organizations can leverage to interact with heterogeneous healthactors.1. IntroductionNowadays, there is a strong trend to coordinate the development of health insuranceprogrammes with social security programmes. This also involves the coordination ofwelfare benefits with other social plans.Additionally, health organizations are increasingly required to interact with each other, inthe context of various coordination initiatives that are being driven in many countries.These coordination initiatives mainly seek to balance two strategies: expandinguniversal coverage of risk and strengthening public health care provisions. [1]In Uruguay, for example, a unified National Integrated Health System (Sistema NacionalIntegrado de Salud, SNIS) was implemented. This system constitutes a frameworkthrough which public and private health organizations deliver health services to thepopulation. Broadly speaking, the SNIS aims at allowing the population to have healthservices of the best possible quality, accessible in the most effective way and
  4. 4. implemented in the most rational way, trying to leverage the existing or future assets inthe involved organizations. [2]One of the requirements to support these coordination initiatives is to have a fluent andsystematic integration among the ICT systems of the organizations. However, thesesystems are usually very heterogeneous regarding technological platforms, capabilities,terminologies and data models, among others, which prevent them from beinginteroperable. Moreover, this heterogeneity can even occur in an intra-organizationalscheme.The development of standards has been a key issue in achieving interoperability atvarious levels. However, standards are not always adopted by health organizations, aneven if they are adopted, they present some issues which might cause difficulties toachieve end-to-end interoperability [3]. Indeed, the “lack of commonly defined andconsistently implemented standards” has been identified as one of the main barriersthat prevent countries from achieving efficiency improvement through ICTs [4].In this context, it is evident the need for an integration platform which addresses andsolves interoperability issues. This paper first describes concepts, technologies andapproaches regarding building interoperable information systems and analyzes someexamples of how they are being applied within the health domain. Additionally, itproposes solution approaches, combining advanced middleware (i.e. Web Services andEnterprise Services Bus) and semantic technologies, for building an e-health integrationplatform which facilitates the integration of the involved organizations.This work mainly originates from joint activities [6][7][8] with the Banco de PrevisiónSocial (BPS) [5], which is the main social security organization in Uruguay, and othergovernmental Uruguayan organizations. The topics presented in this paper are beingaddressed by the academic group Laboratorio de Integración de Sistemas (LInS) [9].The remaining of this paper is organized as follows. Section 2 describes concepts,technologies and approaches regarding building interoperable information systems andprovides examples of how they are being applied in the health domain. Section 3proposes solution approaches, combining advanced middleware and semantictechnologies, to build a service-oriented e-health integration platform. Finally, section 4presents conclusions and future work.2. Interoperable Health Information SystemsThis section presents various concepts, technologies and approaches for buildinginteroperable information systems and describes initiatives, products and tools whichleverage them in the health domain.2.1 InteroperabilityAchieving interoperability has become an essential requirement in almost every domain,like the public and business sectors. Interoperability has been defined as the ability ofICT systems, and of the business processes they support, to exchange data and toenable the sharing of information and knowledge [10].According to the European Interoperability Framework [10], interoperability can beconsidered at three different dimensions: technical, semantic and organizational.Technical Interoperability covers the technical issues of linking computer systems andservices. Semantic Interoperability is concerned with ensuring that the precise meaningof exchanged information is understandable by any other application that was notinitially developed for this purpose. Organizational Interoperability is concerned withdefining business goals, modeling business processes and motivating the collaboration
  5. 5. of organizations that wish to exchange information and may have different internalstructures and processes.The development of standards has been a key issue in achieving interoperability. Forexample, Web Services [11] standards constitute nowadays the main mechanism toachieve technical interoperability in a heterogeneous ICT environment. Moreover, theWeb Services-Interoperability (WS-I) [12] organization is an industry consortium thatseeks to enhance interoperability among Web Services implementations by publishingimplementation guidelines (e.g. WS-I Basic Profile 1.0) with the goal of enhancinginteroperability. Additionally, Semantic Web standards [13] provide mechanisms tosupport semantic interoperability.In the health domain, interoperability is also an essential issue. The Office of theNational Coordinator for Health Information Technology (ONC) [14] consider thatinteroperable health IT can improve individual patient care in numerous ways likeproviding complete, accurate and searchable health information, a more efficient andconvenient delivery of care, earlier diagnosis and characterization of diseases andincreased efficiencies in administrative tasks, among others. Additionally, the USFederal Health Information Technology Strategic Plan states that “to effectivelyexchange health information, health IT systems and products must use consistent,specific data and technical standards” [15].2.2 Health StandardsDuring the last decades, many health standards have been developed and are currentlybeing adopted by various health actors. For example, various international standardshave emerged to standardize the way clinical information is represented and structured.The open standard OpenEHR [16] defines a generic reference model of clinicalinformation that is based on an ontological analysis of the healthcare domain. It onlyrepresents the minimum most important semantic clinical concepts and its archetypesconstraint this model by defining specific clinical concepts. For example, the OpenEHRreference model deals with generic clinical observations, but it does not include theblood pressure, which is a particular observation.As well, the Health Level Seven (HL7) [17] organization develops standards forexchanging, managing and integrating health information. It also has a reference model,but it is aimed to model the information to be exchanged among systems, unlike theOpenEHR that models the internal architecture of medical record systems. HL7information model contains clinical, demographic and accounting concepts, as it is anemerging standard in the USA where the health system is closely linked to insurancecompanies, so that accounting transactions were considered within the model. HL7includes the CDA (Clinical Document Architecture), a standard that seeks to representany kind of electronic medical document for interchange.Another standard of interest in the health domain is the CEN/ISO 13606, which is amodel for information exchange compatible with the OpenEHR model. Also, the ASTMCCR (Continuity of Care Record) information model seeks to model medical summariesto communicate them among different health services. OMG COAS (ClinicalObservation Access Service Model) provides an information model for communicatingclinical observations on a given patient. Finally, the International Healthcare TechnologyStandards Developing Organization is rapidly promoting SNOMED CT as the preferredterminology in healthcare.2.3 Service Oriented ArchitectureService Oriented Architecture (SOA) is a logical way of designing a software system toprovide services in a network, via published and discoverable interfaces. SOA enables
  6. 6. interoperability and flexibility by converting monolithic and static systems into modularand flexible components, represented as services, which can be requested viatechnology standards. [18]A SOA facilitates many of the tasks of developing enterprise applications, like theirintegration, the development of business processes and leveraging legacy systems.Additionally, a SOA provides the flexibility and agility that business users require,allowing them to define coarse grained services which can be combined and reused toaddress current and future business requirements. [18]Healthcare organizations manage a large amount of software systems, which usuallyneed to integrate with each other, and must address evolving clinical requirements. Aswell, organizations increasingly need to interact with other organizations. In this context,SOA can provide healthcare organizations the mechanisms to support reuse andsharing of system resources in an intra or inter-organizational scheme. [19]There are currently many projects and initiatives in the health area which are taking thisdirection.In Denmark, for example, a service-oriented architecture based on Web Services wasbuilt to support the online exchange of health care data among the variousheterogeneous IT systems in the health sector. The architecture forms a federation ofWeb Services and enables secure and reliable authentication of end-users andsystems. As well, the architecture is based on national and international standards andspecifications. [20]Additionally, the Healthcare Services Specification Project (HSSP) [21] is a collaborativeinitiative, between HL7 and the Object Management Group (OMG), which sees theneed to specify services to support the information technologies in the health area. Inthe context of this project, a practical guide to SOA in healthcare [22] has beenelaborated.2.4 Web ServicesA Web service is a software system identified by a URI, whose public interfaces andbindings are defined and described using XML, and whose definition can be discoveredby other software systems. These software systems may then interact with the WebService in a manner prescribed by its definition and using XML based messagesconveyed by Internet protocols. [23]The Web Service technology is based on three fundamental standards: Simple ObjectAccess Protocol (SOAP), Web Service Description Language (WSDL) and UniversalDescription Discovery and Integration (UDDI). Additionally, many others standards,know as WS-*, have emerged to address advanced requirements like security andtransactions, among others.Web Services are the most common way to provide technical interoperability amongheterogeneous software systems. Additionally, given their characteristics, Web Servicesare the preferred technology to implement services in a SOA. In healthcare, WebServices are also being used to achieve these goals. Indeed, many efforts are beingmade to provide guidelines in using health specific standards with Web Servicesstandards.For example, the Web Services profile for HL7 (HL7WSP) [24] has the goal of providingimplementation best practices to promote the interoperability among applications whichexchange HL7 (version 3) messages, using Web Services. The profile considersrecommendations of other organizations, like the Web Services Interoperability (WS-I),to leverage previous performed efforts to promote interoperability.
  7. 7. Additionally, Integrating the Health Enterprise (IHE) [25] is an initiative driven byhealthcare professionals and industry actors, with the goal of improving the way inwhich computer systems in healthcare share information. To this end, a set ofguidelines have been elaborated to promote the coordinated use of establishedstandards such as DICOM and HL7, and their use with Web Services standards.2.5 Enterprise Service BusAn Enterprise Service Bus (ESB) is a standards-based integration platform thatcombines messaging, Web Services, data transformation, and intelligent routing toreliably connect and coordinate the interaction among heterogeneous applications. [26]Even thought Web Services constitute a solid base to implement SOAs, their point-to-point nature might affect maintainability and scalability of the solutions implemented withthis technology. In this context, the ESB provides a middle integration layer, withreusable integration and communication logic, to enable the interaction between clientsand services in a SOA. The ESB accept requests in the form of messages, over which itcan perform different mediation operations (e.g. message transformation, validation andenrichment), to solve heterogeneities between clients and services. The ESB promotesloosely couple interactions between clients and services, and allows separating theintegration and communication logic from the business logic implemented by theservices.Most ESBs provide capabilities to support transport protocol conversion, messagetransformation, message routing and reliable messaging, among others.ESBs can be leveraged in many ways to address interoperability issues and toimplement SOAs in healthcare organizations. Indeed, various ESB-like products areincorporating health specific features.Microsoft, for example, provides an Accelerator for HL7 [27] to extend Biztalk Servercapabilities by delivering a comprehensive HL7 messaging solution that enables sharingof patient information within and between healthcare organizations. Additionally, Mirth[28] is an open source healthcare messaging integration engine, which was built on topof Mule (an open source Java ESB). Mirth allows message filtering, transformation androuting, and provides an integration server that supports a variety of messagingstandards protocols for connecting to external systems, and numerous databases forstoring message data.2.6 Metadata and Semantic TechnologiesMetadata is structured information that describes, explains, locates, or otherwise makesit easier to retrieve, use, or manage an information resource. Metadata is often calleddata about data or information about information [29]. Describing resources withmetadata might facilitate interoperability.Metadata schemes are sets of metadata elements designed for a specific purpose, suchas describing information resources of a specific domain. The definition or meaning ofthe elements is known as the semantics of the scheme. [29]Even though, there is not a unique language to express metadata in a digital way,during the last years a set of standard specifications have been developed (e.g. XML,RDF and OWL) in the context of the Semantic Web [31][32] Activity of the World WideWeb Consortium (W3C). Figure 1 illustrates the stack of standards of the W3C, puttingon its bottom, the less semantic technologies and standards and on top, the mostexpressive and rich ones.
  8. 8. Figure 1 - Semantic Web Standard Stack [34]The eXtensible Markup Language (XML) constitutes a syntactic base for the rest of thestandards. The Resource Description Framework (RDF) is a data model based in triplesobject-attribute-value. Additionally, formal ontology has recently emerged as aknowledge representation infrastructure for the provision of shared semantics tometadata [33]. An ontology is an explicit specification of a conceptualization, where aconceptualization is an abstract, simplified view of the world that we wish to representfor some purpose [30]. An ontology can be defined using the Web Ontology Language(OWL).In a Web Service context, OWL and RDF are two semantic standards too broad andgeneral to express the semantics of a Web Service. Therefore, standards like OWL-S[35], WSDL-S [36] and WSMO [37] have emerged, expanding the possibilities toachieve this challenge in a more specific and effective way. Web Services built usingSemantic Web technologies are commonly known in the literature as Semantic WebServices and are becoming a very useful resource to address the semanticinteroperability problem.In an e-health environment, the Artemis [38] and Miuras [39] projects are two examplesof the application of semantic technologies to solve this challenge.The Artemis project addresses the interoperability problem during the exchange ofmessages between client and Web Services that use different health standards. Theyuse the domain knowledge exposed by the existing healthcare informatics standards todefine a Service Functionality and a Service Message ontology. The ServiceFunctionality ontology is used to specify the operational meanings of Web services andit is based on HL7. The Service Message ontology is used to specify the semantics ofWeb service messages and is developed through electronic healthcare record basedstandards such as ENV 13606 and GEHR [40].On the other hand, the Miuras project is developing a semantic integration engine thatsimplifies the exchange of information between health applications and healthinformation systems of a hospital. The engine simplifies the integration ofheterogeneous systems using the HL7 and ISO 13606 health standards.3. Towards an e-health Integration PlatformThis section presents solution approaches towards building an integration platform,which leverages the facilities provided by middleware and semantic technologies toaddress interoperability issues within an e-health domain.
  9. 9. The integration platform is proposed in the context of a SOA and integrates thecapabilities of ESBs, ontologies and Semantic Web Services.3.1 General DescriptionThe proposed solution [8] addresses the problem presented in Figure 2, where varioushealth organizations, that need to collaborate, support different version of standards tointeract with other organizations (e.g. HL7 v2 and v3). Moreover, some organizationsmight not support any standard. Figure 2 - Organizations supporting and not supporting standardsIn this context, if an organization needs to interact with the rest of the organizations, ithas to know how to deal with the different standards or proprietary mechanisms theymanage. This might be a suitable solution when the number of organizations is small,but as this number grows this solution becomes harder to implement and maintain.Figure 3 presents an alternative solution which consists of an integration platform that,leveraging enterprise service bus and semantic mechanisms, addresses these matters.Within this platform, health organizations publish the services they provide to allowother organizations to discover and consume them. Figure 3 - e-health Integration Platform
  10. 10. The solution proposes using an Enterprise Service Bus (ESB) and extending it withhealth specific capabilities. For example, the extended ESB incorporate components toperform health standards related transformations. As well, it includes components toinvoke Semantic Web Services.In order to consume the services published in the platform, clients send XML messagesto the extended ESB. This allows decoupling clients and services in terms of thecommunication protocols and the health standards they used. It also provides locationtransparency, that is, clients do not need to know the real location of the services inorder to consume them.Additionally, the solution requires the definition of a global ontology, defined in OWL,which includes the identified health domain concepts (e.g. Patient, Doctor, etc). Eachinteracting organization has to map their communication data model to the conceptsdefined within the global ontology. This might be performed by an expert user in chargeof administrating the platform.Organizations have to publish their services, implemented as Web Services, in aSemantic Web Services directory. These services have to be described using OWL-Sand the concepts within the global ontology. For example, an organization might specifythat a Web Service receives as an input parameter a Doctor and return as a responsethe list of Patients associated with this Doctor. Both Patient and Doctor are conceptsdefined in the global ontology.When the ESB receives an XML request, it uses the defined mappings to transform thisinput in an instance of the global ontology. This allows querying the Semantic WebServices Directory in order to find a suitable service to fulfill the request, for example,based on the specified input parameter. Once a service is found, it is invoked and theresponse is transformed back to the communication format used by the client. In thisway, clients and services can interact without having to agree in the standards they use.3.2 Implementation DetailsThe proposed solution was prototyped focusing in HL7 v2.x and HL7 v3 standards. Theprototype was built with JBoss ESB [41] which is the ESB product provided by JBoss.Additionally, various technologies were used to assist in performing the requiredtransformation, discovery and invocation tasks. HAPI (HL7 Application ProgrammingInterface) [42], for example, is an open-source, object-oriented HL7 2.x parser for Java.It was used to parse HL7 messages and be able to manipulate them as Java objects,which simplifies this task. On the other side, Jena [43] is a Java framework for buildingSemantic Web applications. It provides a programmatic environment for RDF, RDFSand OWL, among others. Finally, OWL-S API [44] provides a Java API forprogrammatic access to create, read, write, and execute OWL-S described atomic aswell as composite services.4. Conclusions and Future WorkThroughout this paper, solution approaches to build an e-health integration platformwere analyzed. Concretely, various technologies for building interoperable informationsystems were described, along with their application in an e-health domain. SOA, forexample, can provide healthcare organizations the mechanisms to support reuse andsharing of system resources. ESBs allow decoupling clients and services at differentlevels (e.g. communication protocol, supported health standards, etc). As well, semantictechnologies, in particular semantic Web Services, provide suitable mechanisms toachieve semantic interoperability.
  11. 11. Based on this analysis, solution approaches were proposed in order to integrateadvanced middleware and semantic technologies in a consolidated platform.Concretely, an integration platform, based on an ESB, a global ontology and semanticWeb Services, was specified and prototyped, as a first step towards building an e-healthintegration platform. This platform allows publishing and consuming semanticallydescribed e-health services, and leverages ESB capabilities to transform and routerequests and responses in order to resolve heterogeneities between clients andservices.Despite of the fact that integrating semantic and ESB technologies in a consolidatedplatform allows taking advantage of the capacities of both technologies, there are manyissues that still remain open. For example, although standards are a key element forachieving interoperability, current standards present some problems which preventthem from guaranteeing end-to-end interoperability [3]. Additionally, most middlewaretechnologies (e.g. ESBs) do not specifically address issues related with the healthdomain. Therefore, an interesting work in this direction is to enrich current middlewareplatforms to explicitly address and support health standards and solve domain specificproblems. Finally, given the mediation role of the ESB, it becomes a suitable place toperform runtime adaptation tasks (e.g. replace service, use cache, etc) in order tomaintain the quality of service of the provided services.5. References[1] International Social Security Association. Dynamic Social Security for the Americas: Social Cohesion and Institutional Diversity. 2010. http://www.issa.int/Resources/ISSA- Publications/Dynamic-Social-Security-for-the-Americas-Social-Cohesion-and-Institutional- Diversity [Accessed: July 2010][2] MSP. La construcción del Sistema Nacional Integrado de Salud. 2009. http://www.msp.gub.uy/andocasociado.aspx?2967,16873 [Accessed: July 2010][3] G. Lewis, E. Morris, S. Simanta, and L. Wrage, “Why Standards Are Not Enough to Guarantee End-to-End Interoperability,” Composition-Based Software Systems, 2008. ICCBSS 2008. Seventh International Conference on, 2008, pp. 164-173.[4] OECD. DRAFT CHAPTER FOR PRIORITIES PUBLICATION ON CO-ORDINATION OF CARE. 2010.[5] Banco de Previsión Social (BPS). http://www.bps.gub.uy/ [Accessed: July 2010][6] Pablo Pazos. Arquitectura Orientada a Servicios para Sistemas que utilizan HL7. Proyecto Taller de Sistemas de Información 3. 2008. http://www.fing.edu.uy/inco/cursos/tsi/TSI3/2008/trabajos/HL7.pdf[7] Pablo Pazos. Análisis de capacidades de transformación de mensajes en JBossESB. Proyecto Taller de Sistemas de Información 4. 2008. http://www.fing.edu.uy/inco/cursos/tsi/TSI4/2008/trabajos/JBossESB-HL7.pdf[8] Martín Biganzoli, Diego San Estaban. Interoperabilidad en Información de Salud basada en tecnologías de Middleware y Semánticas. Proyecto de Grado 2009. http://www.fing.edu.uy/~pgesbhl7/docs/Informe_Final.pdf[9] Laboratorio de Integración de Sistemas (LInS). http://www.fing.edu.uy/inco/grupos/lins/ [Accessed: July 2010][10] IDABC, European Interoperability Framework for pan-European eGovernment services, 2004.[11] Web Services Architecture. http://www.w3.org/TR/ws-arch/ [Accessed: July 2010][12] Web Services Interoperability Organization. http://www.ws-i.org/ [Accessed: July 2010][13] Semantic Web Activity. http://www.w3.org/2001/sw/ [Accessed: July 2010][14] Office of the National Coordinator for Health Information Technology (ONC) http://healthit.hhs.gov/ [Accessed: July 2010][15] T. Benson, Principles of Health Interoperability HL7 and SNOMED, Springer, 2009.
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