Servicios Terminológicos para el (re)uso efectivo de la Información Clínica - Dra. Jussara Macedo

1. Terminology Service
Jussara Rötzsch
Based on: Ian McNicoll
Christopher Chute

2. What do we need?
Messaging An EHR that is
• Independent of implementation
technology
• Independent of clinical system
developer
• Enables access to multiple clinical
Query applications
• Designed for longevity and re-use
Terminology
Content Specifications
Information Models

3. The Problem
• Terminology systems vary considerably in both content
and structure.
– NDF‐RT
– RxNorm
– SNOMED‐CT
– ICD‐9 and ICD‐10
– CPT
– etc
• Requirements of terminology vary widely
• Implementation decisions of terminology vary widely
• Storage formats may differ (relational database, XML,
...)
© 2002‐2009, Health Level
March, 2009 3
Seven, Inc.

4. Real world use of SNOMED CT
• Clinicians
– Need to be able to find the term that they need easily
– Need to use SNOMED terms correctly – good subsets
are safe
– Transparent to the end user
• Applications
– Need to be able to deploy SNOMED and use it reliably
in their apps
– Need to be able to query reliably
1.4

5. Common Terminology Services (CTS)
• Purpose is to specify a common Application
Programming Interface (API) to access
terminological content
• Client software doesn’t have to know about
specific terminology data structures and/or
how to access them
• Server software can plug and play with many
clients
© 2002‐2009, Health Level
March, 2009 5
Seven, Inc.

6. Common Terminology Services API
• Allows Client Software to be developed
Independently from Service Server Software
• Allows Terminology Plug‐and‐Play
• Allows Client Plug‐and‐Play
• Defines a “Functional Contract”
© 2002‐2009, Health Level
March, 2009 6
Seven, Inc.

7. CTS API
...
Application
Interface CTS
Service
Data
© 2002‐2009, Health Level
March, 2009 7
Seven, Inc.

8. CTS API
HL7
Application Vocab Find codes having “*myelitis”
Browser
Interface CTS
HL7
Terminology
Service Server Select * from VOC_concept_designation
WHERE text like ‘%myelitis’
MS Access
Data
Tables
© 2002‐2009, Health Level
March, 2009 8
Seven, Inc.

9. CTS API – Different Client, Same Service
IHC
Application
Picklist Find codes having “*icillin”
Tool
Interface CTS
HL7
Terminology
Service Server Select * from VOC_concept_designation
WHERE text like ‘%icillin’
MS Access
Data
Tables
© 2002‐2009, Health Level
March, 2009 9
Seven, Inc.

10. CTS API – Different Server, Same Client
IHC
Application
Picklist Find codes having “*icillin”
Tool
Interface CTS
APELON
DTS
Select * from conc_repr
Service WHERE text like ‘%icillin’
AND ...
SNOMED Oracle
Data
CT Tables
© 2002‐2009, Health Level
March, 2009 10
Seven, Inc.

11. CTS API – Distributed Services
IHC
Application
Picklist Find codes having “*icillin”
Tool
Interface CTS
<msg><soap....><filter=“*icillin”...</msg>
Service
Web
Data Internet Service
Portal
© 2002‐2009, Health Level
March, 2009 11
Seven, Inc.

12. Common Terminology Services
Message Processing
Message Processing Application
Message Processing Application
Application
Message API
Vocabulary API
Vocabulary
Vocabulary
Vocabulary
© 2002‐2009, Health Level
March, 2009 12
Seven, Inc.

13. OpenEHR (Ocean)Terminology Server
Use cases
Maintenance
Multiple
Languages &
subsets

14. Terminology Server
• Stores named queries
• Caches complex queries
• Caches saved between
sessions
Ocean Terminology
Server
UK
English SNOMED-CT
extension

15. Process
User determines which part(s) of SNOMED‐CT
hierarchy is of interest (including which
subsets)
Can choose to:
– Include a node
– Exclude a node (pass through)
– Exclude a node and all the children of a node
(exclude)
– Include the node for navigation only
– Hoist the children to be peers of the parent

16. Blood groups – raw views

17. Blood Groups simple list (all terms)
• Choose all relevant blood groups
• Hoist all nodes to be peer with parents
This gives a flat list of terms

18. ABO Blood Groups 3‐layer tree
• The hierarchy of
ABO blood groups
Navigate
Select

19. Terminology Query language
• <?xml version="1.0" encoding="utf‐8" ?>
Start at ABO
• <ots:query blood group
• xmlns:ots="urn:xmlns:oceaninformatics.biz:schema:OTSQuerySchemav2"
• name="BloodTypev2"
• language="en‐us" Set root to
• terminology="Snomed"
• cacheMode="Permanent"> Navigate
• <childNodes>
• <concept conceptId="112143006"
• operation="Navigate"> Iterate down the
• <childNodes> IS_A relationship
• <relatedConcept operation="Navigate"
• relationship="116680003">
• <childNodes>
• <relatedConcept operation="Select"
• relationship="116680003">
• </relatedConcept>
• </childNodes>
• </relatedConcept>
• </childNodes>
• </concept> Make all nodes
• </childNodes>
• </ots:query> with an IS_A
relationship
selectable

20. ABO Blood Groups 3‐layer tree restructured
Placeholder
Placeholder
Select
Navigate

21. ABO Blood Groups 3‐layer tree restructured
code
• <?xml version="1.0" encoding="utf‐8" ?>
• <ots:query
• xmlns:ots="urn:xmlns:oceaninformatics.biz:schema:OTSQuerySchemav2" Navigate
• name="BloodTypev2"
• language="en‐us"
• terminology="Snomed"
• cacheMode="Permanent">
• <childNodes>
• <placeHolder text="Blood Types">
• <childNodes>
• <concept conceptId="112143006"
• operation="Passthrough"> Select
• <childNodes>
• <relatedConcept operation="Navigate"
• relationship="116680003">
• Placeholder <childNodes>
• <placeHolder text="Rh subtypes">
• <childNodes>
• <relatedConcept operation="Select"
• relationship="116680003">
• <constraints>
• Placeholder <lexicalConstraints>
• <lexicalConstraint matchRule="MustMatch">
• <searchString>*Rh*</searchString>
• </lexicalConstraint>
• </lexicalConstraints>
• </constraints>
• </relatedConcept>

22. OTS Features
• Terminology support
– Support for multiple terminology
• linking concepts by relationships (hierarchies)
• property based
– Support for terminologies in their native structures
– Access to terminologies in any database technology
• Queries
– Queries may be pre‐defined and made available to all users
– Queries based on queries
– Provide a high‐level mechanism for identifying concepts relevant
to local requirements

23. OTS Features
• Query language
– XML based
– terminology‐independent
– allows selection or navigation around relevant concepts depending on the
situation.
– powerful expressive capabilities across trees, multiple links and iterative structures
• Visual interface
– hierarchical navigation
– rapid text searches
– visual specification of queries
• Computer Interfaces
– Global Web Service interface accessible to all
– Class library available for local .NET usage

26. Q&A
jussara.macedo@openehrfoundation.org