IHE Gazelle Objects Checker HL 7 WGM Paris
IHE Gazelle Objects. Checker : HL 7 WGM Paris 2015 Abderrazek Boufahja IHE-Europe, Gazelle team abderrazek. boufahja@ihe-europe. net Eric Poiseau IHE-Europe, Gazelle team Eric. poiseau@inria. fr
Context ¢ IHE / IHE-Europe IHE is an initiative by healthcare professionals and industry to improve interoperability between healthcare IS ¢ IHE Europe : A non-for-profit association attached to IHE International ¢ Develop Test tools and organize European Connectathon ¢ ¢ Gazelle ¢ ¢ Connectathon ¢ ¢ an open source test-bed platform that provides a wide set of tools to validate information exchange between healthcare system => for more details visit the website : http: //gazelle. ihe. net A meeting between healthcare systems developers in order to test the interoperability between their systems/devices => last one : Luxembourg IHE CDA content profiles ¢ A list of profiles restricting the CDA standards with specific requirements 2
Our problem ! ¢ Need to test XML documents for conformity with specification CDA documents : IHE, ep. SOS, national projects… ¢ But also other documents (XDW, HL 7 v 3, XD*, …) ¢ ¢ Need for a methodolody where inheritence can be an advantage. ¢ ¢ Model based methodology Need better specifications for better testing ¢ We’d like to test the implementation of the specs, not the specs !
Conformance validation steps
Gazelle Objects. Checker Principles (1) A methodology to describe informal requirements in healthcare IT specifications based on CDA standard, into a formal description ¢ An architecture that allows : ¢ The validation of the conformance of any kind of XML requirements ¢ Provide metrics and documentary features ¢ Improve the coupling between rules and requirements ¢ Support the validation of inheritance between specifications ¢ Source : e. Health Suisse, Format d’échange, Rapports de laboratoire soumis à déclaration en Suisse (Projet) 5
Gazelle Objects. Checker Principles (2) Requirements Entry Automatic and Description of thethorough structure of the XML doc. Injection of rules and requirements into the model Testing → OCL constraints Scripts that extract information from UML models and generate structured texts related to these models 6
Gazelle Objects. Checker Implementation ¢ Multiple CDA validators (each testing one “content profile” specification) were developed and used by IHE and multiple national projects around the world : 14 IHE CDA documents validators ¢ 11 ep. SOS CDA documents validators ¢ 15 CDA document validators for vaious national projects ¢ 30 000 CDA documents validated against Gazelle Objects. Checker validators ¢ Heavily used during European and North American Connectathon and ep. SOS Projectathon ¢ Easily integrated into third party repositories as a front end validation tool ¢ 7
Standalone Document/Message Validation EVSClient : a front end to the conformance validation services used by the Gazelle Platform (http: //gazelle. ihe. net/EVSClient) 3 - Report Gazelle Test Platform 1 - HTTP : Upload of document EVS Front End HL 7 v 2/v 3 Validator CDA Validator Schematon Validator XDW Validator 2 – WS Call Dicom Validator SUT 8
EVSClient demonstration for CDA validation
EVSClient installations Venice Region (Italy) e. Santé (Luxembourg) ep. SOS (EU Cross-border) Kanta (Finland)
Need of strong fondations
HL 7 CDA R 2 requirements ¢ Extraction of all CDA requirements not expressed in the XSD schema from: HL 7 Clinical Document Architecture, Release 2. 0 ¢ HL 7 Reference Information Model, Release 2. 07 ¢ Data Types - Abstract Specification, Release 1, 2004 ¢ XML Implementation Technology Specification - Data Types, Release 1, 2004 ¢ ¢ The output : a document named « HL 7 CDA R 2 Basic Requirements» (reference 12) A unique reference that uniquely identifies the CDA basic requirements ¢ Number of identified requirements : 160 1
Application 1: National Projects Samples Studies 153 samples from different European and north American national projects 2200 errors found using Gazelle Objects. Checker : an average of 14 errors per document !!!
Application 2: IHE Schematrons Validation Studies ¢ 1700 “valid” IHE CDA samples based on schematrons validation ¢ 18000 errors detected by gazelle Objects. Checker ¢ 11 ¢ ¢ errors per document 60 different kind of errors found Conclusion ? 1 - Many CDA basic requirements are not checked by the schematrons 2 - The weakness of schematrons could spread to healthcare systems
Most Frequent Errors in CDA Documents found by Gazelle Objects. Checker § DTITS-007: the use of reference element under an ED data type § CDADT 008 /CDADT-006: the use of attributes related to CD data type (null. Flavor, code, display. Name, etc) § CDADT-011: the use of UUID structure § CDADT-013/CDADT-014: the specification of URL references §… 2 kind of errors : • Errors that may create troubleshooting for document consumer systems • Errors that Corrupt of Healthcare Information 1
Tooling: CDA Basic Requirements Coverage Analysis ¢ Requirement Coverage Indicator Specification ¢ Describes the % of requirements tested by a validation tool, regarding the total number of requirements 1
Conformance validation steps • art-decor • trifolia • MDHT • Gazelle Objects. Checker • Eclipse Instance Editor • Nist Validation tool • schematrons from regional projects • etc
Tooling: CDA Basic Requirements Coverage Analysis 1
CDA conformance quantification ¢ How to identify the conformance of a CDA document regarding the CDA standard and validated against a validation tool ? (Requirements Coverage Indicator, Number of errors found) ( Icov , Nerror) Tools of validation SHALL always provide a report of their coverage indicator
Gazelle Objects. Checker Advantages ¢ Requirement coverage capability support of complex requirements (complex algorithm, etc) ¢ conditional /iterations validation ¢ XML elements type verification ¢ Data types requirements checking ¢ Runtime access to coded value sets from a repository of terminologies ¢ Easier to maintain than hand written schematrons ¢ Validation is faster than schematrons ¢ Linking between the rules tested and the requirements from the specifications ¢ 2
Gazelle Objects. Checker Principles (2) Requirements Entry Automatic and Description of thethorough structure of the XML doc. Injection of rules and requirements into the model Testing → OCL constraints Scripts that extract information from UML models and generate structured texts related to these models 2
Art-decor and Gazelle Objects. Checker coupling Art-Decor Requirements Entry Objects. Checker 2
Getting specifications right: The ART-DECOR Framework. . . is an open-source tool and a methodology for various multidisciplinary stakeholders of healthcare information exchange ¢. . . supports collaboration of team members within and between governance groups and allows separation of concerns with different views on one single documentation for different domain experts ¢. . . supports creation and maintenance of templates, value sets, data sets and more ¢ …supports shared building block repositories for templates, value sets and data sets ¢
ART-DECOR in Europe ¢ Shared repositories with collection of artifacts Template Repository (building bocks for clinical document definitions) and Value Sets (code lists) ¢ Functional Models (datasets) ¢ Sharing artifacts between countries has already started by Germany, Austria, Netherlands ¢ ¢ ART-DECOR specs Input for Testing Tool Testing “Scripts”
ART-DECOR & IHE Europe ¢ Memorandum of Understanding signed: ¢ Synergistic tooling: ART-DECOR Framework and IHE Gazelle Objects. Checker facilitate the creation and consistent standardized documentation of CDA based specifications and ¢ support rigorous compliance validation and testing. ¢ ¢ The overall goal is: ¢ to provide these projects with easy-to-use efficient combined tooling that enhance the quality of their implementations and information exchange.
Advantages of coupling Objects. Checker with art-decor Art-decor moves rigor at point of Content Profiles/Impl. Guides documentation and avoid discovery of issues/gaps at the time Objects. Checker input is created. ¢ Reduces gaps and misunderstanding of CDA specifications ¢ Automate the generation of formal OCL description avoiding test tool manual entry ¢ 2
Conclusion ¢ ¢ ¢ Insufficiency of XSD schema validation for CDA documents Numerous CDA validation tools are far from covering 100% of basic CDA requirements The national projects in Europe need to improve the validation tools they use to increase the quality of their CDA documents Validation tools should provide requirements coverage reporting Gazelle Objects. Checker was efficient to detect errors in national projects samples Perspective Possibility to extends Gazelle Objects. Checker methodology to other XML based standards like HL 7 V 3, FHIR, etc ¢ Possibility of coupling Gazelle Objects. Checker with some editors of CDA requirements ¢ 2
More details. . ¢ More details : paper “Model-based Analysis of HL 7 CDA R 2 Conformance and Requirements Coverage” (IHIC 2015) ¢ Web pages : http: //gazelle. ihe. net ¢ Contacts ¢ IHE Europe: ¢ eric. poiseau@ihe-europe. net ¢ abderrazek. boufahja@ihe-europe. net ¢ Art-Décor ¢ hl 7@kheitmann. de 2
Any question ?
How does IHE Gazelle Objects. Checker compares to Schematron ¢ Schematrons are useful but have inherent limitations in term of coverage. Requirements generally not covered : ¢ CDA R 2 base standards requirements : Generic data types requirements ¢ Complex requirements between CDA elements ¢ XML elements type checking ¢ ¢ Typical Content Profile/implementation Guides requirements ¢ Complex attributes specifications (like the person identifiers structure/algorithm, telecom structures, etc) ¢ Complex Conditional requirements between sections or entries ¢ Specific data types requirements ¢ ¢ Relationships consistency with other document content and metadata Elements based on the paper to be presented at IHIC conference: “Model-based Analysis of HL 7 CDA R 2 Conformance and Requirements Coverage” ¢ Coverage of CDA R 2 requirements improvements : typically from 5060% to 100%. For details see above paper. 3
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