LOINC and SNOMED CT David Markwell Head of Implementation and Education International Health Terminology Standards Development Organisation 1

Enabling SNOMED CT and LOINC to work together David Markwell Head of Implementation and Education Includes material developed by Farzaneh Ashrafi and Suzanne Santamaria 2

Agreement completed ▪Announcement 24 July 2013 ▪Joint IHTSDO and RII press release: ▪ ▪Full text of the agreement: ▪ ▪The same materials are also on the LOINC site 3

Objectives of the agreement ▪To support consistent coding of order entry and result reporting ▪by addressing coding and modeling of terminology content in the domains covered by LOINC orders and observations ▪To avoid unnecessary duplication of effort ▪To develop cooperation between IHTSDO & Regenstrief  Not a one-off activity  Not an acquisition or merger  Not an exclusive arrangement A long-term working relationship 4

Short introduction to LOINC 5

LOINC design summary ▪LOINC Term ▪Represents a measurement, question or observable ▪Consists of ▪LOINC Code (Numeric with dash and check-digit) ▪LOINC Name (what SNOMED CT would call a term) ▪Is specified by values applied to six Part Types ▪Component ▪Property ▪Time ▪System ▪Scale ▪Method ▪LOINC Part ▪Represents a value for one of six dimensions used to specify a LOINC Term ▪Consists of ▪LOINC Part Number (LP prefix, numeric then dash and check-digit) ▪LOINC Part Name (what SNOMED CT would call a term) 6

LOINC Example – Sodium concentration in serum of plasma 7 LOINC CodeLOINC Name LOINC Term Sodium [Mass or Moles/volume] in Serum or Plasma Part TypePart No.Part Name ComponentLP Sodium PropertyLP6860-3SCnc [Substance Concentration] TimeLP6960-1Pt [Point in time (spot)] SystemLP7576-4Ser/Plas [Serum or Plasma] ScaleLP7753-9Qn Method

LOINC Example – Colour of Urine LOINC CodeLOINC Name LOINC Term5778-6Colour of Urine Part TypePart No.Part Name ComponentLP Colour PropertyLP6886-8Type TimeLP6960-1Pt [Point in time (spot)] SystemLP7681-2Urine ScaleLP7750-5Nom [Nominal] Method 8

The practical approach ▪Maps between LOINC Parts and SNOMED CT ▪Addition of content where necessary to complete these maps ▪LOINC terms linked to “SNOMED CT Expressions” to provide SNOMED CT semantic view of LOINC Terms ▪Limited additions of content subject to specific restrictions intended to limit duplication of effort and content

▪ Greater consistency in coding of order entry and results reporting ▪ Improvements in each terminology ▪ Improved analytics and quality control ▪Query LOINC via SNOMED hierarchy and relationships ▪Better identification and maintenance of laboratory tests value sets for public health reporting ▪Enhanced tracking and management of infectious disease outbreaks ▪ Integrates disparate elements in EHRs ▪Lab test in LOINC with elements in patient chart in SNOMED (e.g. allergies, chief complaint, vital signs, age) ▪Enables clinical decision support, may aid in reimbursement Value

▪ Internal project team – currently 6 individuals ▪Head of Terminology, Head of Content Development, Head of Implementation and Education, Head of Delivery, Terminologists ▪ LOINC project team contact ▪ Executive Policy Group (3 from RII and 3 from IHTSDO) ▪ Observable and Investigation Model Project ▪Subproject on CollabNet ( those interested in participating contact SSA or FAS) ▪ Project groups (Substance Redesign; Organisms; Microbiology) ▪ External collaborators: ▪US Veterans Administration ▪Kaiser Permanente ▪ IHTSDO Content Committee: ▪Guidance, coordination with other IHTSDO initiatives ▪ Contractors: ▪Developing implementation guidance: BITAC Roles of individuals and groups

▪ Scope ▪Laboratory LOINC ▪Vital signs ▪Physiologic measurements ▪Anthropomorphic measurements and evaluations ▪ Phases ▪Initial ▪Top 2000 lab LOINC tests ▪Microbiology ▪Chemistry ▪Vital signs ▪Subsequent ▪Remainder of lab LOINC ▪Measurements Project scope

Map LOINC parts to SNOMED Jan 2014 June 2014 April 2015 Map LOINC codes to SNOMED expressions Roadmap Technology Preview release Candidate baseline release Alpha release July 2015 November 2014 Develop distribution format Create SNOMED value sets for LOINC codes

1.Collaboration a.Invite participation by stakeholders b.Regular meetings (internal group; EPG; KP) c.Ensure approach works with other concurrent design projects (e.g. Substance Redesign) d.Publicize work and progress 2.Content development a.Add and update content to SNOMED to complete the LOINC Parts map (techniques, substances, etc.) b.Determine the best approach for handling complex concepts c.Create documentation of process and outcomes d.Create and deliver alpha release and Technology Preview 3.Test and obtain feedback a.Document and test the Observables model (including description logic) b.Document the quality test plan c.Review feedback on releases from stakeholders Development phase objectives

1.Collaboration a.IPaLM SIG, internal project groups (e.g. Substance Redesign) engaged b.Regular meetings held (internal group; EPG; KP) c.Posters at ICBO and SNOMED CT Showcase this Fall 2.Content development a.SNOMED concepts added for LOINC Part mapping, metadata, etc. b.Draft implementation guidance released July 2014 c.alpha release released May 2014 with documentation a.117 LOINC Terms d.Development of Technology Preview Structure Process e.Technology Preview released October 2014 with documentation a.2100 LOINC Parts in LOINC Part to SNOMED RefSet b.9700 LOINC Terms in LOINC Term to Expression RefSet Development phase progress

3. Test and obtain feedback a.Report on implementation horizon and scope released April 2014 b.Documented and tested the Observables model (including description logic and creation of OWL ontology) c.Performed quality test plan for functionality and reproducibility d.Analyzed feedback on alpha prototype and modified content Development phase progress continued

▪ Prototype: Released in May 2014 ▪ Initial Technology Preview: Released in October 2014 ▪ Repeat of Technology Preview: Scheduled for March 2015 ▪ Candidate baseline: Scheduled for July 2015 ▪ Actual baseline: TBD (July 2015 release becomes baseline if no changes needed) Summary of sequence for content development and release

Proposed release formats (1) LOINC Parts to/from SNOMED CT – LOINC Map Refset file FieldData typePurpose idUUID A 128 bit unsigned integer, uniquely identifying the reference set member. effectiveTimeTime Specifies the inclusive date at which this change becomes effective. activeBoolean Specifies whether the member's state was active or inactive from the nominal release date specified by the effectiveTime field. moduleIdSCTID Identifies the member version's module. Set to a child of |Module| within the metadata hierarchy. refsetIdSCTID Identifies the reference set. referencedComponentIdSCTID A reference to the SNOMED CT concept being mapped to/from the LOINC Part Code. mapTargetString The value of the LOINC Part Code to which the concept is mapped. attributeIdSCTID SNOMED CT concept representing the attribute to which the referencedComponentId applies. Usually derived from the LOINC Part Type. correlationIdSCTID The correlation between the SNOMED CT concept and the LOINC Part Code. Subtypes of | SNOMED CT source code to target map code correlation value| Exact match, Broad (SNOMED CT) to narrow LOINC, Narrow (SNOMED CT) to broad (LOINC), Partial overlap originOfContentSCTID Indication of whether concept was initially in one of the terminologies (LOINC or SNOMED CT) and added to the other as part of mapping or was in both terminologies at the outset. Values Originally in LOINC, Originally in SNOMED CT, Originally in both LOINC and SNOMED CT

Proposed release formats (2) LOINC Terms to/from SNOMED CT – Expression Refcodeset file FieldData typePurpose idUUID A 128 bit unsigned integer, uniquely identifying the reference set member. effectiveTimeTime Specifies the inclusive date at which this change becomes effective. activeBoolean Specifies whether the member's state was active or inactive from the nominal release. moduleIdSCTID Identifies the member version's module. refsetIdSCTID Identifies the reference set. referencedComponentIdSCTID A reference to the SNOMED CT | LOINC code system | (a filler to keep to Refset format) mapTargetString The value of the LOINC Part Code to which the concept is mapped. expressionString SNOMED CT Expression that most closely represents meaning of the LOINC Term code. definitionStatusIdSCTID Indicates whether or not the expression contains a sufficient definition of the LOINC Term Code in the mapTarget field. Subtypes of: | Definition status correlationIdSCTID The correlation between the SNOMED CT concept and the LOINC Part Code. Subtypes of | SNOMED CT source code to target map code correlation value| Exact match, Broad (SNOMED CT) to narrow LOINC, Narrow (SNOMED CT) to broad (LOINC), Partial overlap originOfContentSCTID Indication of whether concept was initially in one of the terminologies (LOINC or SNOMED CT) and added to the other as part of mapping or was in both terminologies at the outset. Values Originally in LOINC, Originally in SNOMED CT, Originally in both LOINC and SNOMED CT

Expression representation ▪SNOMED CT Compositional Grammar ▪Planned approach – use author normal form expressions ▪Proximal supertypes ▪Differential non-redundant defining relationships ▪Actual expressions in Technology Preview ▪SNOMED CT Observable entity concepts are not yet modeled ▪There are no intermediate sufficiently defined supertypes ▪Thus for (almost) all LOINC Term codes: ▪Proximal inferred supertype is: |Observable entity| ▪Expression refinements are full nested definitions

mapTargetexpression : =( : =( : = , = , = ), = , = ) LOINC Term to SNOMED Expression Refset Example

mapTargetexpression | Calcium:ACnc:Pt:Bld:Ord | |Observable entity|: |Specified by|= ( |Observation procedure|: |Observes|= ( |Feature of entity|: |Inheres in|= |Blood|, |Towards|= |Calcium|, |Property type|= | Arbitrary concentration|), |Direct site|= |Blood specimen|, |Scale|= |Ordinal value|) LOINC Term SNOMED attribute concept SNOMED value concept

Implementation Guidance on using SNOMED CT and LOINC together ▪Phase 1: Scoping and Horizon Scan ▪Completed: 10 th April ▪Phase 2: Developing Guidance ▪Completed draft: 11 th July 2014 ▪Consultation and commenting by I&E Committee ▪Current version: 14 th October

Implementation Guidance SNOMED and LOINC Phase 1 deliverables: Horizon Scan ▪Use of SNOMED CT and LOINC together ▪12 structured use case summaries based on phone interviews ▪Revised based in feedback from interviewees ▪High-level summary of findings ▪National spread: 7 different countries (6 Members + 1 Non-Member) ▪Patterns of terminology use … 24

Implementation Guidance SNOMED and LOINC Phase 2 deliverables ▪Guidance on models for combined use ▪Advice on situations in which LOINC and SNOMED CT codes can be effectively used together. ▪E.g. laboratory observations, test results, vital signs, microorganisms, antibiotic sensitivities, specimen types, etc. ▪Take account of existing guidelines (e.g. HL7, CIMI) ▪E.g. HL7, CIMI or other relevant initiatives ▪Added value from maps & expression associations ▪Enhanced semantic processing for LOINC users ▪Greater completeness of coverage from SNOMED CT + LOINC 25

Guidance on use of SNOMED CT and LOINC together (outline) ▪Short Introduction to SNOMED CT ▪Features of SNOMED CT ▪Benefits of SNOMED CT ▪Short Introduction to LOINC ▪Features of LOINC ▪Benefits of LOINC ▪Cooperative work overview ▪Map Correlation and Origin Reference Set ▪Expression Association Reference Set ▪Benefits of products of the Cooperative Work ▪Guidance on Use of SNOMED CT and LOINC Together ▪Relevant Clinical Scenarios ▪Practical guidance on uses of SNOMED CT and LOINC ▪Practical uses of Part Maps and Expression Associations

Examples of Guidelines (1)

Examples of Guidelines (2)

▪ Content ▪Alpha prototype files (including OWL file) ▪ ernational_releases/frs.3_other_releases.loinc_snomed_alpha_prototype ernational_releases/frs.3_other_releases.loinc_snomed_alpha_prototype ▪ Technology Preview files ▪ rnational_releases/frs.technology_preview_packages rnational_releases/frs.technology_preview_packages ▪ Implementation ▪Horizon and scoping report (Phase 1) ▪ ▪Draft implementation guidance (Phase 2) ▪ ▪ Observables redesign ▪ ▪ RII – IHTSDO Agreement ▪ Cooperation_Agreement_between_IHTSDO_and_RII_ pdf Cooperation_Agreement_between_IHTSDO_and_RII_ pdf References

QUESTIONS & DISCUSSION