Introduction to the HL7 Terminfo Project IHTSDO Implementation SIG Webinar 5 June, 2012 Robert Hausam, MD

HL7 Organization Health Level Seven International Founded 1987 Not-for-profit, ANSI-accredited standards developing organization dedicated to providing a comprehensive framework and related standards for the exchange, integration, sharing, and retrieval of electronic health information that supports clinical practice and the management, delivery and evaluation of health services

HL7 – What Does It Mean? "Level Seven" refers to the seventh level of the International Organization for Standardization (ISO) seven-layer communications model for Open Systems Interconnection (OSI) - the application level The application level interfaces directly to and performs common application services for the application processes

HL7 Vision To create the best and most widely used standards in healthcare

HL7 Mission HL7 provides standards for interoperability that improve care delivery, optimize workflow, reduce ambiguity and enhance knowledge transfer among all of our stakeholders, including healthcare providers, government agencies, the vendor community, fellow SDOs and patients

HL7 Mission (Cont.) In all of our processes we exhibit timeliness, scientific rigor and technical expertise without compromising transparency, accountability, practicality, or our willingness to put the needs of our stakeholders first

Terminfo Project History Project began January 2005 Balloted as DSTU (Draft Standard for Trial Use) –First balloted and approved as DSTU May 2006 –Re-balloted Jan. 2007, Sept. 2007, May 2009 –DSTU expired May 2009 –DSTU document jointly published by HL7 and IHTSDO

Contributors David Markwell Ed Cheetham Bob Dolin Sarah Ryan Ian Townend Beverly Knight Kent Spackman Others

Terminfo Project Scope The primary scope of this implementation guide is to provide guidance for the use of SNOMED CT in the HL7 V3 Clinical Statement pattern Includes: –Structured Documents (CDA Release 2) –Patient Care –Orders and Observations –Models using the Clinical Statement CMET

Terminfo Project Scope Guidance should also be applied to the use of SNOMED CT in other HL7 V3 models that share features with the Clinical Statement model, unless domain specific requirements prevent this While other code systems (such as LOINC or ICD9) may be required or even preferable in some situations, these situations are outside the scope of this guide

Terminfo Project Scope Achieved by consensus development of guidance relating to: –Areas of semantic overlap – for example attributes supported by both models such as negation –Areas specific to each technology – for example constraining appropriate SNOMED CT content for each Clinical Statement class

Terminfo Project Scope This guidance takes the form of: –editorial principles –technical constraints and mappings where these are possible –worked illustrative examples –discussion and explanation of open issues

Terminfo Purpose/Overview The purpose of this guide is to ensure that HL7 Version 3 standards achieve their stated goal of semantic interoperability when used to communicate clinical information that is represented using concepts from SNOMED CT

Terminfo Purpose/Overview The guide takes account of: –The SNOMED CT concept model including those elements concerned with the representation of context –The structure and semantics of the HL7 Reference Information Model (RIM)

Terminfo Purpose/Overview –The advantages and disadvantages of each option are identified and recommendations are made on which option (or options) should be used to provide for the greatest level of semantic interoperability –In cases where alternative options are recommended advice is included on mapping between them

Document Structure/Content “How to read this document” Section 1 – IntroductionSection 1 Section 2 (normative) - Detailed guidance on dealing with specific overlaps between RIM and SNOMED CT semanticsSection 2 –Subsections include: A brief introduction to the item An explanation of the potential overlap A statement of rules and guidance on usage A supporting discussion and rationale

Document Structure/Content “How to read this document” Section 3 (informative) - Set of examples and patterns for representing common clinical statementsSection 3 Section 4 (informative) - Describes normal forms, including their use with SNOMED CTSection 4 –Also discusses considerations for transformations between various common representations and SNOMED CT or HL7 RIM based normal forms

Document Structure/Content “How to read this document” Section 5 (normative) - Contains a number of constraints on SNOMED CT Concepts applicable to relevant attributes in each of the major classes in the Clinical Statement patternSection 5 Appendix A (informative) – Discussion of the potential overlaps between an information model and a terminology model and the pros and cons of various possible approaches to managing these overlapsAppendix A

Document Structure/Content “How to read this document” Appendix B (reference) – References to relevant documents including SNOMED CT specifications and compositional grammarAppendix B Appendix C (informative) – Changes to the document since the last ballotAppendix C Appendix D (informative) – Identifies known open issues in SNOMED CT that limit the completeness and consistent application of some of the guidance in the documentAppendix D

Document Structure/Content “How to read this document” Appendix E (informative) – More detailed discussion of approaches to normative constraints on SNOMED CTAppendix E –Identifies the need for further development of formal vocabulary rules to support this

Terminfo 2 June Needed to either withdraw Terminfo as a standard or re-engage project Discussed within HL7 and IHTSDO - Decided that maintaining and continuing to jointly publish as a standard was important for both organizations New project officially launched January 2012 Retains content and builds on work from the previous DSTU

Terminfo 2 Areas of expanded scope –HL7 V2 artifacts Messages –LOINC terminology Areas of overlap including system (specimen) and method axes Clarification –All V3 artifacts Including CDA and templates As well as messages and services

Leaders/Contributors Rob Hausam (HL7) David Markwell (IHTSDO) Dan Vreeman (Regenstrief) Beverly Knight Jim Case Daniel Karlsson Others

Terminfo 2 Principles Recommendations will provide guidance on overlap between the terminology and information models –Include when (and when not) to post-coordinate Recommendations will be driven by use cases –Guide will include specific and consistent examples of clinical information –Use cases will include not only clinical information but also technical constraints

Terminfo 2 Principles Recommendations will align with the goals of terminology development organizations (including HL7 and others) Recommendations must be implementable by stakeholder user communities –This may mean that recommendations must support more than one approach

Terminfo 2 Principles Recommendations will support consistent precision of representation between the terminology and the information model –Semantics must be explicit, even in tools that do not easily support explicit semantics (e.g., class diagrams, RDBMS) –When recommendations provide options, they will specify patterns for semantically rigorous transformations among options (Last two may overlap a bit)

Terminfo 2 Objectives Clearly and explicitly guide standards modelers in incorporating SCT and LOINC values into HL7 V2 and V3 artifacts in ways that fulfill the semantic constraints of both information model and terminology Provide implementers (e.g., software developers) with clear guidance on their options for representing data in instances

Terminfo 2 Objectives Provide information consumers (e.g., report writers or researchers) with clear descriptions of the semantics of conforming artifacts Provide terminology developers with clear feedback on the uses to which terminologies are put

Current Project Activities Conference calls –Tomorrow! – Wednesday 6 June, 12:00 Eastern Daylight Time (UTC – 4) –Calls are every other week (fortnightly) HL7 Wiki Terminfo 2 page –Work in progress –

Use Case – Microbiology Reporting Purpose –Identify guidelines in the domain of microbiology reporting terminology when using LOINC for the observation and SNOMED CT for the result value Scope –V2, V3 & CDA

Use Case – Microbiology Reporting The guidelines will cover the LOINC observations used in Microbiology reporting where a coded result value is a recommended option Include recommendations and guidance on: –The use of interpretation of the result value –When to use generic LOINC observations and organism specific observations Type of result value codes which should be used and which ones should be avoided for each observation

Use Case – Microbiology Reporting –The use of specimen information –The use of method information –The use of isolate observations & result value –The use of sensitivity observations and result values –Others??

HL7 Vancouver WGM Terminfo Session Highlights Further develop microbiology and other use cases Representation of methods at levels of granularity greater than provided by LOINC Clear guidance needed for organism-specific cultures identify standard mechanisms for using a SNOMED CT code in conjunction with a LOINC code

HL7 Vancouver WGM Terminfo Session Highlights Issues related to method and devices concepts required for representing information regarding neoplasms –In V3 this is a participation relationship Procedure.methodCode and Observation.methodCode are both part of the HL7 definition of method –SNOMED CT takes a narrower view –Implications of SNOMED CT proposed technique hierarchy development/reorganization

HL7 Vancouver WGM Terminfo Session Highlights Need “Environmental scan” of existing implementation guides related to method Add guidance section for Observation.interpretationCode New section added for Organism related observables New section added for Specimen

Questions? Rob Hausam David Markwell Beverly Knight