SNOMED CT • Jostein Ven, KITH, 02.11.2004
SNOMED CT • Jostein Ven, KITH, 02.11.2004
SNOMED CT viewed as a reference terminology
Jostein Ven, advisor, KITH
SNOMED CT • Jostein Ven, KITH, 02.11.2004
Systemized Nomenclature of Medicine – Clinical Terms
• System of Health Care concepts and associated terms developed by the College of America Pathologists
• 344.000 concepts
• 1.361.960 relations between concepts
• 19 top concepts in the system of concepts
• 12 ”axes” (or ”independent” modules)
SNOMED CT • Jostein Ven, KITH, 02.11.2004
Some history
• SNOP (Systemized Nomenclature of Pathology)
• Snomed (I/II) –six axes
• ”The Norwegian SNOMED” - Den norske SNOMED
• Used in Norway today in the area of pathology
• SNOMED III (SNOMED International) – eleven axes
• SNOMED RT
• SNOMED CT
• SNOMED RT + Clinical Terms v3 (Read Codes)
SNOMED CT • Jostein Ven, KITH, 02.11.2004
Translation of SNOMED CT into Norwegian?
• Nordic cooperation, 2nd meeting i December
• Method for automatic translation (Iver Nordhuus, KITH)
• Based on already translated coding schemes such as ICD-10 and NCSP.
• Evaluation of translation
• Maintenance of Norwegian translation
• Correspondence between the content of SNOMED CT, the cost of translating and maintaining the translation, and the actual need of the Norwegian Health Sector?
SNOMED CT • Jostein Ven, KITH, 02.11.2004
Top concepts in SNOMED CT
SNOMED CT • Jostein Ven, KITH, 02.11.2004
Axes in SNOMED I and II
• Topography
• Morphology
• Aetiology
• Function
• Disease/diagnosis
• Procedure
SNOMED CT • Jostein Ven, KITH, 02.11.2004
Akser i SNOMED III (”SNOMED International”)
• Kilde: Coding matters, Vol. 8, No. 2, September 2001.
SNOMED CT • Jostein Ven, KITH, 02.11.2004
SNOMED RT code structure
• Kilde: Coding matters, Vol. 8, No. 2, September 2001.
SNOMED CT • Jostein Ven, KITH, 02.11.2004
Relationship names ranked by occurence in SNOMED CT
Relation name Number
Is a 447123
Onset 114555
Finding site 106394
Course 64202
Severity 64144
Episodicity 63952
Method 62667
Associated morphology 58642
Priority 50319
Procedure site 50284
Part of 47821
Access 43237
Causative agent 32967
Interprets 18185
Has active ingredient 17360
Laterality 16418
Occurrence 10639
SNOMED CT • Jostein Ven, KITH, 02.11.2004
Relasjoner og akserRelation name A C D F G J L M P R S T
Is a 9703 29629 114309 56779 6775 5059 27192 6058 91226 57507 1413 41473
Onset 112349 2123 14 6 62 1
Finding site 88017 17969 12 3 57 20 308 4 4
Course 63043 1113 7 3 36
Severity 62967 1121 7 3 5 40 1
Episodicity 62848 1059 7 3 33 2
Method 8 1 103 12 62512 31
Associated morphology 21 58274 313 3 31
Priority 7 1 89 12 50173 36 1
Procedure site 1 110 15 50142 15 1
Part of 67 11 87 32 47624
Access 1 80 12 43122 22
Causative agent 32844 112 6 2 1 2
Interprets 342 1124 15577 4 34 208 182 100 611 3
Has active ingredient 17202 143 4 10 1
Laterality 5 1 7 19 16386
Occurrence 10260 368 10 1
SNOMED CT • Jostein Ven, KITH, 02.11.2004
Semantisk nettverk (is-a-relasjonen)
SNOMED CT • Jostein Ven, KITH, 02.11.2004
Procedures in SNOMED CT
• Norwegian coding scheme for non-surgical procedures (MEDPROS)
• Procedures concept are connected to other defining concepts via relations.
• SNOMED CT as a source for procedures
• Examples
SNOMED CT • Jostein Ven, KITH, 02.11.2004
Example of procedureSNOMED CT concept Associated concepts Relation
Cerebral blood flow radionuclide study (procedure)
Brain structure (body structure) Procedure site
Cerebral blood flow radionuclide study (procedure)
Introduction - action (qualifier value) Method
Cerebral blood flow radionuclide study (procedure)
Diagnostic - procedure intent (qualifier value)
Has intent
Cerebral blood flow radionuclide study (procedure)
Priorities (qualifier value) Priority
Cerebral blood flow radionuclide study (procedure)
Intracranial vascular structure (body structure)
Procedure site
Cerebral blood flow radionuclide study (procedure)
Surgical access values (qualifier value) Access
Cerebral blood flow radionuclide study (procedure)
Radionuclide imaging - action (qualifier value)
Method
Cerebral blood flow radionuclide study (procedure)
Brain imaging with vascular flow (procedure)
Is a
Cerebral blood flow radionuclide study (procedure)
Imaging - action (qualifier value) Method
Cerebral blood flow radionuclide study (procedure)
Blood vessel structure (body structure) Procedure site
Cerebral blood flow radionuclide study (procedure)
Radioactive isotope (substance) Direct substance
SNOMED CT • Jostein Ven, KITH, 02.11.2004
Use of SNOMED CT
• Encoding of documentation
• Can be used instead of other coding schemes, or as a common ground
• Automatic mapping into other coding schemed: ICD-10, NANDA, NIC and possibly more in the future (ICF, NCSP, …)
SNOMED CT • Jostein Ven, KITH, 02.11.2004
SNOMED CT • Jostein Ven, KITH, 02.11.2004
Mapping across coding schemes
• Arrive at a better inter-professional problem understanding by mapping coding schemes that are specific to a profession onto each other.
• Doctors: ICD-10, NCSP, ICPC-2
• Nurses: NANDA, NIC, Perioperativ Nursing Data Set
• Physical therapists: ICF, …
SNOMED CT • Jostein Ven, KITH, 02.11.2004
Overlap between coding schemes:
SNOMED
ICD-10
ICF NANDA
Common domain:
Problem/illness
SNOMED CT • Jostein Ven, KITH, 02.11.2004
Cross Mapping
• Metodologi og tabeller for mapping fra begreper i SNOMED CT til en eller flere koder andre kodeverk
• One way only!
• Coverage and level of detail varies, mapping is a real challenge
• Information loss is very possible in many cases
SNOMED CT • Jostein Ven, KITH, 02.11.2004
Tables involved in cross mapping
SNOMED CT • Jostein Ven, KITH, 02.11.2004
Cross mapping SNOMED CT to ICD-9-CM
SNOMED CT • Jostein Ven, KITH, 02.11.2004
Goal of mapping between coding schemes:
• Common problem understanding
• Prerequisites
• Translation SNOMED CT into Norwegian
• More extensive use of non-doctor coding schemes.
• More cross-mappings
• Feasability analysis of bi-directional mapping, i.e. mapping from coding scheme into SNOMED CT