1. New ITS and Wrappers R2 Charlie McCay charlie@RamseySystems.co.uk

2. Agenda Introduction Projects / activities XML ITS 1.1 New ITS Specification Wrappers R2

3. Introduction Editor XML ITS R1 Structures Co-chair ITS SIG Project Lead Wrappers R2 project Editor XML ITS R1.1 Editor New ITS Specification Active member datatypes taskforce

4. Projects - ITS XML ITS R1.1 New ITS specification New ITS Guide ISO Datatypes Specification Abstract Datatypes R2 XML ITS Datatypes R2

5. Projects Wrappers R2 Wrappers R2 MCCI – Transmission Infrastructure MCAI – Message Control Act Infrastructure QUQI – Query Infrastructure MFMT – Registry Infrastructure

6. XML ITS 1.1 Single Issue Revision Improved versioning for current systems Minimal change – easy upgrade path Consistent with New ITS

7. Status Quo – XML ITS R1 The specification states that “local extensions” MUST be in a foreign namespace The specification states that different versions of the same artefact are expected to be an XSLT transform apart The Specification is silent on how unexpected content in the hl7 namespace should be treated (though the committee expectation was that it would be treated as an error) The distinction between breaking and non-breaking changes is not made (all changes are assumed to be breaking)

8. Precedents SPL Structured Product Labelling XML 1.1 XSLT 2.0

9. SPL SPL is a CDA like document for Pharmaceutical Product Labelling, and is strongly supported by the FDA (and others) It supports the foreign namespace extensibility, but states that RIM-compliant extensions should be in the HL7 namespaces, with an XML attribute “HL7extension” (with non-empty content) to indicate that it is not defined in the underlying SPL specification.

10. XML 1.1 The set of well formed XML instances was extended to support later versions of Unicode, and to support additional newline characters. All XML 1.0 documents are accepted by XML 1.1 processors Switch from “what is not defined is forbidden”, to “what is not defined is permitted” unless explicitly forbidden

11. XSLT 2.0 Has a an extension and fallback mechanism for selectively supporting V2 features within a V1 stylesheet, and for providing fallback support when features (of the XSLT or extensions) are not supported

12. XML ITS 1.1 examples

13. New ITS - Key Implementation Problems Node count and deep nesting, with each XML element requiring processing by developer and application Schema do not support tools or code reuse Requirements to instance mapping not clear Datatype property constraints hard Model Reuse (20 similar medication models) Mapping to different host systems

14. Fixed and Default Values Provide support for generic processing Cost is “ugliness” and “low data density” Implementers not keen to access separate definitions for every message type Need to explore name stability strategies Impact on related sets of messages, and versioning of messages over time HL7v3 as storage format…

15. HL7v3 XML as storage format HL7 does recognise this as a requirement for CDA documents (persistence) Is a requirement for store-and-forward systems, and there is a continuum between these and registries Registry interfaces that address non- functional requirements must address this issue

16. New ITS example - RMIM view

17. New ITS example - XML Instance

18. Wrappers R2 Time box to get predictable delivery New layers to support horizontal standards (SOA) – with virtualisation in the transport protocol Batching requirements

19. Wrappers R2 diagram

20. References Wrappers R2 http://informatics.mayo.edu/wiki/index.php/ MCCI/CACT_R2_Project http://informatics.mayo.edu/wiki/index.php/ MCCI/CACT_R2_Project New ITS – hl7v3 onlinehl7v3 online – http://informatics.mayo.edu/wiki/index.php/ITS_ SIG http://informatics.mayo.edu/wiki/index.php/ITS_ SIG (mayo wiki – login “wiki” password “wikiwiki”)