Editorial principles for UK Edition of SNOMED CT
Program
me
NPFIT
Sub-Prog
/
UK Terminology
Centre
DOCUMENT RECORD ID KEY
NPFIT-FNT-TO-DSD-1086
Project
Prog.
Director
Ken Lunn
Owner
Ian Arrowsmith
Author
Ian Arrowsmith
Version
Date
14/07/11
Version
v0.13
Status
Draft
Editorial principles for UK Edition of SNOMED CT
1
Amendment History:
Version Date
Amendment History
0.1
31st July
2009
Revised following internal circulation
0.2
30th Sept
2009
Revised following consideration by UKTC Edition
Committee
0.3
30th Dec
2009
Revised following workshop
0.4
4th Jan 2010
Revised following internal comment
0.5
16/02/2010
Revised following comment from UKTC Edition
Committee
0.6
30/3/2010
Revised following internal consultation and restructured
0.7
2/7/10
Additional principles added
0.8
9/8/10
Significant revision following formal review of
principles by UKTC Edition Committee
0.9
13/10/10
Further approval/re-drafting of principles following
quarterly meeting
0.10
26/1/11
Further approval/re-drafting of principles following
quarterly meeting
0.11
16/5/11
Further approval/re-drafting of principles following
quarterly meeting
0.12
03/06/11
Re-drafted following additional meeting
0.13
14/07/11
Further approval/re-drafting of principles following
quarterly meeting
Forecast Changes:
Anticipated Change
When
To be updated following every quarterly meeting
Unknown
Reviewers:
This document must be reviewed by the following. Indicate any delegation for sign
off.
Name
Ian Green
Signature
Title / Responsibility
Date
Version
UKTC Quality Officer
Aug 2010
0.9
2
James Paton
UKTC Clinical Director
Aug 2010
0.9
Jo Goulding
UKTC Pharmacy work
stream lead
Aug 2010
0.9
Tom Seabury
SNOMED
Implementation team
lead
Aug 2010
0.9
UKTC Edition
Committee
Various
Aug 2010
0.9
Date
Version
Approvals:
This document requires the following approvals:
Name
Signature
Title / Responsibility
Ken Lunn
Director DS&P
Paul Jones
Chief Technical Officer
NHS
Distribution:
<Document text>.
3
Document Status:
DRAFT.
Related Documents:
These documents will provide additional information.
Ref no Doc Reference Number
Title
Version
1
Glossary of Terms:
List any new terms created in this document. Mail the NPO Quality Manager to
have these included in the master glossary above [1].
Term
Acronym
Definition
4
Contents
1
Purpose .............................................................................................................. 8
2
Audience............................................................................................................. 8
3
Scope ................................................................................................................. 8
4
Background ........................................................................................................ 9
5
4.1
The UK Edition ............................................................................................. 9
4.2
IHTSDO editorial principles .......................................................................... 9
UK General editorial principles ......................................................................... 10
5.1 Term construction/naming conventions (nb some principles exist in draft
form but unpublished by IHTSDO) ........................................................................ 12
5.1.1
Extent of pre-coordination (UK)
12
5.1.2
Synonyms
13
5.1.3
Plurals
14
5.1.4
Punctuation
15
5.1.4.1
Quotation marks
15
5.1.4.2
Apostrophes
15
5.1.4.3
Hyphens
16
5.1.4.4
Colons
16
5.1.4.5
Forward slash
17
5.1.4.6
Single plus sign (+)
18
5.1.4.7
Plus sign +++
18
5.1.5
Eponyms
19
5.1.6
Abbreviations
20
5.1.7
Verbal nouns
21
5.1.8
Past and future tense verbal forms
22
5.1.9
Language dialects
22
5.1.10
Negation concepts
23
5.1.11
„Either‟/‟or‟ Procedures
23
5.1.12
Use of numerics
23
5.1.13
Character „case‟ conventions
24
5.1.14
Accented and unusual characters
25
5
5.1.15
„Disorder‟ naming conventions
25
5.1.16 Use of hyphen for tagging to identify content designed for a specific
limited use case
26
6
5.1.17
Authority dependent concepts
27
5.1.18
Concepts of „classification‟ origin
28
Appendix 1 - Domain-specific editorial principles ............................................. 29
6.1
Activities of daily living ................................................................................ 29
6.2
Religion and religious affiliation .................................................................. 29
6.3
UK Administrative concepts ........................................................................ 30
6.4
Representation of „official‟ forms and certificates in healthcare .................. 31
6.5
Scored Assessments .................................................................................. 32
6.6
International Paediatric and Congenital Cardiac Code (IPCCC) procedures33
6.6.1
Repair Procedures
33
6.6.2
“Mixed” Vessel Procedures
33
6.6.3
Confluence procedures
34
6.6.4
Combined Procedures and pre-coordinated IPCCC content
34
6.6.5
Baffle Devices
34
6.6.6
Additional techniques and sub-procedures
34
6.7
Diagnostic Imaging procedures .................................................................. 35
6.7.1
X-ray imaging
35
6.7.2
Computed tomography
36
6.7.3
Ultrasonography
36
6.7.4
Magnetic resonance imaging procedure
37
6.7.5
Radionuclide imaging (Nuclear medicine)
38
6.7.6
Positron emission tomography
38
6.7.7
Single photon emission computed tomography
38
6.7.8
Fluoroscopy imaging
38
6.7.9
Dual energy X-ray photon absorptiometry
39
6.7.10
Multiple modality procedures
40
6.7.11
Imaging guided procedures
40
6.7.12
Contrast
41
6.7.13
View/Projection/Technique adjustments
42
6.8
FocusActOrEvent Concepts ....................................................................... 42
6.9
Diabetes ..................................................................................................... 43
6.10
Levels of risk – pre-coordination.............................................................. 44
6
6.11
Nature and number of invitations – eg to screening ................................ 44
6.12
“On examination” and “complaining of” concepts .................................... 45
6.13
Findings of assessments/treatments and previous treatments ................ 45
6.14
“History of”, “no history of”, “family history of” and “no family history of”
(finding) 46
7
6.15
Inclusion of drug/vaccine name in procedures ........................................ 47
6.16
Record headings/items against which a value or text may be assigned .. 48
6.17
Concepts relating to actions undertaken as part of specific legislation.... 48
6.18
Pre-coordination of laterality .................................................................... 49
Appendix 2 – UK approved abbreviations......................................................... 50
7
1 Purpose
The purpose of this document is to describe the editorial policies as applied to the
UK Edition of SNOMED CT. It is intended to supplement rather than replace any
IHTSDO Editorial policies and applies to both UK specific content and content
added initially to the UK Edition but intended for eventual inclusion in the
International Edition.
2 Audience
The intended audience for this paper are those involved in the maintenance of
SNOMED CT in the UK and for those submitting requests for change to the UK
Edition.
3 Scope
The document is concerned with the nature and form of the descriptions for
concepts included in the UK extension of SNOMED CT, whether they are
permanent members of this extension or whether they are pending move into the
International Edition.
The descriptions covered are the Fully Specified Name (FSN), Preferred Term
(Pref term) and Synonyms (Syn).
The nature of the concepts in the UK extension ranges from mainstream clinical
procedures or findings, to administrative legislation and electronic record
components.
Some editorial principles will apply to all content and others will apply to particular
concept types or domains.
These principles are aimed at all of enhancements, gaps and corrections to
International guidance as well as to UK-specific items. In order to understand the
document, each item is classified as one of these. This will aid in the tracking of
any principles of UK origin that are adopted internationally. It should therefore be
possible to determine whether any new principle has International, National or
even „transient‟ National applicability
The rules described here are assured by the UK Edition Committee, as and when
they agree to changes, the document will be updated. Proposed changes to the
Editorial principles should be brought to the UKTC Edition Committee (UKTC Ed
Comm) for consideration.
Each section of the document has a tabular header which clearly shows the current
status of that principle.
8
The document will be updated at least as frequently as the UK Edition is released –
currently every six months on 1st April and 1st October.
The modelling and super-type assignment are out of scope for this paper and are
dealt with in the UK edition terminology authoring guidance (to be written).
4 Background
4.1 The UK Edition
The UK edition of SNOMED CT is maintained by the UK Terminology Centre
(UKTC) of NHS Connecting for Health.
The UK Edition contains the International edition plus some UK created elements,
which sit in the UK extension and is structurally partitioned from the International
data.
The UK extension is made up of two different types of content, one for UK-specific
content and one for content of UK origin which is intended for eventual inclusion in
the International Edition.
Requests for change to the UK Edition should be made using the dedicated portal
at https://www.uktcregistration.nss.cfh.nhs.uk/requests.
It is acknowledged that not all UK extension content is yet conformant with the
guidance expressed here but these rules will be applied to all new content and
over time to existing content.
4.2 IHTSDO editorial principles
There are a number of resources produced by the IHTSDO which describe how the
content of SNOMED CT should be developed and maintained, these are constantly
updated and users should refer to the IHTSDO website for the latest version, these
include the following:
SNOMED CT Style Guide: Introduction and Overview
Introduction and overview of the Style Guide, which serves as the primary
reference regarding the editorial policies and content of SNOMED CT.
SNOMED CT Style Guide: Body Structures - Anatomy
Description of editorial policies regarding the intended meanings of the anatomy
content in SNOMED CT.
9
SNOMED CT Style Guide: Clinical Findings
Description of editorial policies regarding the intended meanings of the clinical
findings content in SNOMED CT.
SNOMED_CT Style Guide: Morphologic Abnormalities
Description of editorial policies regarding the intended meanings of the morphologic
abnormalities in SNOMED CT.
SNOMED CT Style Guide: Procedures
Description of editorial policies regarding the intended meanings of the procedure
hierarchy in SNOMED CT.
SNOMED CT Style Guide: Situations with Explicit Context
Description of editorial policies regarding the intended meanings of the hierarchy
under situation with explicit context in SNOMED CT.
IHTSDO_Editorial_Policy-Content_Inclusion_Principles_and_Process
The document addresses the question of what content belongs and does not
belong in SNOMED CT. Its primary purpose is to guide the decisions of those
individuals charged with triaging and incorporating new content as it is submitted
via any channel. Its secondary purpose is to provide guidelines for submission of
new content.
This document will also be generally applicable to the UK extension with
exceptions for certain pre-coordinated content considered unacceptable to the
International edition.
It is anticipated that this body of resource will increase over time, indeed work is
underway on amalgamating all of the above documents into a single authoritative
editorial document – the full and current list of publications from the IHTSDO can
be found at http://www.ihtsdo.org/publications
5 UK General editorial principles
The UK Editorial principles should supplement rather than change any of the
IHTSDO Editorial guidance and will largely be needed where International
guidance is still to be developed.
In this document, each principle is flagged as either UK-specific or a gap in
International guidance. Those considered a „gap‟ in the internationally published
10
principles may be available in draft form but are not yet formally agreed and
published. As such, this category may have only a transient presence in the UK
editorial principles.
The status of each principle will be clearly stated and will take one of the following
statuses:
Pending
Principle is awaiting consideration of UKTC Ed Comm
Under consideration
Principle has been presented to UKTC Ed Comm
Approved
Principle has been approved by UKTC Ed Comm
Previously approved, under review
A principle previously approved is subject to further consideration by UKTC
Ed Comm
Withdrawn
Principle has been withdrawn from the consideration of UKTC Ed Comm
Not approved, replaced by
Principle has been considered by UKTC Ed Comm but has been replaced
by alternative principle
Considered but rejected
Principle has been rejected by UKTC Ed Comm
Moved to international
A principle, previously approved by the UKTC ED Comm has been formally
accepted for international application and published as part of IHTSDO
editorial principles
The date on which the principle was approved will also be explicitly stated as will
the anticipated date of review.
It is recognised that there are a great many clinically related concepts that are
specific to UK healthcare delivery so criteria will develop over time regarding
whether concept types are permitted or not – each of these will be documented in
these editorial principles as and when they need to be addressed, particularly
those that are introduced to support systems with limited functionality.
The editorial rules that apply to the SNOMED CT UK drug extension will differ in
some aspects where particular representations are necessary to support the safety
requirements of effective drug management. The Editorial principles which apply to
the UK drug extension can be found at:
http://195.97.218.30/dmd_download.htm
11
5.1 Term construction/naming conventions (nb some principles
exist in draft form but unpublished by IHTSDO)
5.1.1 Extent of pre-coordination (UK)
Principle
5.1.1 Extent of pre-coordination
Category
UK
Status
Under consideration
Date approved
Review date
Jan 2011
Many system implementers are working with impoverished information models, and
to deny them certain pre-coordinated coded content may be to prevent their use of
SNOMED at all.
It is anticipated that some degree of pre-coordination will be required in the UK that
may not be permissible in the International edition.
All content of early versions of The Read codes was required to be pre-coordinated
as post-coordination was not possible within the terminology alone. However,
SNOMED CT is designed to support many use cases with attributes which can be
used to qualify other concepts. It is therefore not necessary to express all clinical
notions by the means of extensive pre-coordination but it must still be possible for
meaningful clinical utterances to be single concepts. The balance between what is
acceptable to include as one concept and that which is not permitted is not always
clear and will be expressed for individual use cases in this document.
In the UK, there are some high profile use cases that must be supported across
both the Read codes and SNOMED CT so it is likely that the UK will be more
permissive than the IHTSDO in terms of what pre-coordinated content will be
acceptable in the immediate future.
It is important that a number of criteria are established for application to
submissions to determine whether the requested representation is justified. Some
initial criteria are listed below and will evolve over time and as supplier systems
become more sophisticated.
Criteria for pre/post-coordination
Where a base concept potentially uses a whole „hierarchy‟ as the range for a value
list (eg History of every disorder) then post-coordination will be expected, eg:
Family history of diabetes
The relationship of dates, times, locations or people to events or findings will not be
permitted, eg:
Anaesthesia administered by consultant anaesthetist in theatre
12
Some areas where pre-coordination has been agreed as acceptable in the UK
extension are as follows:
Under care of X
Seen by X
Discharged by X
It is important to note that the presence of existing pre-coordinated expressions in
SNOMED CT does not mean that similar patterns will be accepted in the future.
Whilst some extended pre-coordination may be permissible in the short term it is
important to state in the principles that the expected future end state will be for
post-coordination wherever this does not compromise common clinical utterances.
Concepts where the procedure is combined with the performer will not generally be
permitted. Concepts of the following form will therefore be disallowed:
NHS health check by third party
NHS health check by pharmacist
NHS health check by third party
NHS health check by other
It should be noted that this form has been permitted under the exceptional
circumstances dictated by the swine flu epidemic, eg
PANDEMRIX - first influenza A (H1N1v) 2009 vaccination given by other
healthcare provider
5.1.2 Synonyms
Principle
5.1.2 Synonyms
Category
International „gap‟
Status
Approved
Date approved
7/10/10
Review date
1/12/2012
Narrower synonyms:
If a synonym is more specific than the FSN this is an error, since it does not have
the same meaning. Concepts with synonyms more specific than the FSN are
considered ambiguous.
For Example : FSN: Removal of device (procedure)
SYN: Removal and replacement of prosthetic device
13
Broader synonyms:
If a synonym is more general than the FSN, and there is no common context in
which it has the same meaning as the FSN, the synonym should not be permitted.
Example: FSN: Sprain (morphologic abnormality)
SYN: Joint injury
However, a more general synonym may be considered to be valid when there is a
context where the more general synonym has the same meaning as the FSN
These instances will be rare and should be documented (appendix 3).
Example: FSN: Fluoroscopic femoral angiogram
SYN: Femoral angiogram
Those synonyms which are not
Example: FSN: Uterine fundus (body structure)
SYN: Fundus. Context: obstetrical examination.
Note:
Synonyms of this type are present in the international edition. UK representatives
will seek to influence this policy.
5.1.3 Plurals
Principle
5.1.3 Plurals
Category
International „gap‟
Status
Approved
Date approved
13/4/10
Review date
01/04/12
In general, terms are represented in the singular rather than plural.
For example:
Breast procedure (procedure)
Disease of lung (disorder)
Exceptions
Organizational nodes, also called "grouper" concepts, may have a synonym that is
plural.
14
For example:
Procedures for splenic lesions
Diseases of mitral and aortic valves
Fully-specified names should not be given in plural form unless the concept
necessarily involves multiples. Unintended plurals might mislead data analysts into
incorrectly inferring there were multiples when there was in fact only one.
An unintended plural is the use of a plural in a name for a code that might be
attached to a case where there is only one of the entity being coded.
For example, consider "trochlear lesion" versus "trochlear lesions": Since users will
want to use this code to refer to a single trochlear lesion, the singular form of
"lesion" is correct, and the plural form would be incorrect.
As another example, consider "multiple cranial nerve palsies": In this case, the
word "multiple" indicates that there can never be just one, so a plural form of
"palsies" is correct, and the singular would be incorrect.
5.1.4 Punctuation
5.1.4.1 Quotation marks
Principle
5.1.4.1 Quotation marks
Category
International „gap‟
Status
Approved
Date approved
13/4/10
Review date
01/04/12
Speech marks should not be used in any descriptions.
5.1.4.2 Apostrophes
Principle
5.1.4.2 Apostrophes
Category
International „gap‟
Status
Approved
Date approved
13/04/10
Review date
01/04/12
15
Eponymous terms should not include an apostrophe or final "s" (unless the name
normally ends in "s"). With rare exceptions, concepts with any eponymous terms
should have at least one term that follows this pattern.
The default construction will not include the apostrophe or additional „s‟. However,
where common usage demands it, these are permissible in all descriptions. It is
most often desirable to dispense with the apostrophe in the FSN and pref term but
allow it in the synonym.
For example:
FSN Down syndrome
Pref term Down syndrome
Syn Down‟s syndrome
5.1.4.3 Hyphens
Principle
5.1.4.3 Hyphens
Category
International „gap‟
Status
Approved
Date approved
13/4/10
Review date
01/04/12
These are used to link two related words or names together. There should be no
spaces either before or after the hyphen.
For example:
Zollinger-Ellison syndrome
Tick-borne hemorrhagic fever
Phospho-2-dehydro-3-deoxygluconate aldolase
Preferred place of care – home
Note – Therefore the following pattern using a colon is unacceptable
Preferred place of death: home
5.1.4.4 Colons
Principle
5.1.4.4 Colons
Category
International „gap‟
16
Status
Approved
Date approved
13/4/10
Review date
01/04/12
These are used in the context-dependent categories hierarchy or in concepts
where we separate acronyms from a disorder, or separate a specimen from the
finding identified in that specimen.
For example:
FH: Metabolic disorder
H/O: breast problem
Exceptions: Organisms or substances where the colon is a proper part of the
name; ratios; definitions of tumour stages; and the abbreviation "Re:".
For example:
Salmonella II 43:g,t:[1,5]
Xylocaine mpf 2% with epinephrine 1:200,000 injection
pT3: Tumour invades adventitia (oesophagus)
5.1.4.5 Forward slash
Principle
5.1.4.5 Forward slash
Category
International „gap‟
Status
Approved
Date approved
7/10/10
Review date
1/10/12
These may be used for representing units of measure, as required in the
pharmaceutical products hierarchy and in laboratory test results and units of
measure hierarchies. There should be no space either before or after the slash.
For example:
Nitroglycerin 0.3mg/hr disc
Mesoridazine besylate 25mg/mL injection solution ampoule
There should never be a forward slash in the FSN except for the above examples.
Specifically „and/or‟ construct should never be present in any descriptions.
The forward slash may be used in other description types, eg
17
O/E - abdominal mass palpated (preferred)
Note: there are a number of and/or constructs in the international data. UK
representatives will lobby to influence a change in international policy.
Note: Editorial principles for UK Drug extension may differ in certain respects,
please see dm+d editorial principles at http://195.97.218.30/dmd_download.htm
5.1.4.6 Single plus sign (+)
Principle
5.1.4.6 Single plus sign (+)
Category
International „gap‟
Status
Approved
Date approved
7/10/10
Review date
1/10/12
For combination drug products, a “+” sign should be used.
Note: Editorial principles for UK Drug extension may differ in certain respects,
please see dm+d editorial principles at http://195.97.218.30/dmd_download.htm
5.1.4.7 Plus sign +++
Principle
5.1.4.7 Plus sign +++
Category
UK
Status
Approved
Date approved
7/10/10
Review date
1/10/12
There are a number of concepts in the UK extension where the intent is to express
the deviation of a finding from the expected value, eg
Urine nitrite test = +++ (finding)
It has been agreed that there are a small number of tests where this is the
commonly understood finding/result so representations where „+++‟is the actual
value, then these should be permitted. These principles will only apply to a small
number of findings where a relative value of a finding is being expressed.
However, where the use of the „+‟ is simply intended to emphasise the finding then
it would not be permitted in new submissions but the current concepts can remain.
For example, the following would not be accepted,
eats junk food ++(finding)
18
5.1.5 Eponyms
Principle
5.1.5 Eponyms
Category
International „gap‟
Status
Approved
Date approved
7/10/10
Review date
1/10/12
Eponyms are names that are derived from a proper name, usually the name of a
person who discovered or described the thing originally. They are commonly found
in a wide variety of names in health terminology, ranging across diverse areas
such as anatomic structures, morphologic abnormalities, blood groups, diseases,
findings, and procedures.
For example:
• Rutherford Morrison pouch
• vein of Galen
• Aschoff body
• Kell blood group
• Down syndrome
• Moro reflex
• Whipple procedure
It is neither desirable nor indeed possible to completely avoid the use of eponyms
in a health terminology. Nevertheless, FSNs should avoid including eponyms
wherever possible in order to improve clarity of meaning and to facilitate translation
to other languages. The full description should be used as the FSN, and the
eponymous term can be added as a synonym. For example, the FSN for “Moro
reflex” should use the phrase “infant startle reflex.”
It is permitted and encouraged to include eponyms as designations (non-FSN
terms) whenever they are understandable, reproducible and useful in a given
context. For example, the preferred term for “infant startle reflex” may be “Moro
reflex.”
In most cases, the full description should be used as the FSN, and the eponymous
term can be added as a synonym.
For example:
Fontan operation with conduit from right atrium to pulmonary artery
(procedure)
is a synonym of
Construction of conduit - right atrium to pulmonary trunk (procedure)
Exceptions are allowed for concepts where the eponym is the only precise clinically
relevant name available, and where an artificially constructed non-eponymous
19
name would necessarily be vague or subject to significant misinterpretation.
Examples include “Hodgkin lymphoma” and “Burkitt lymphoma.”
The eponym should only be used in the FSN where clinical convention dictates and
judged on a case by case basis. For instance where the eponym is the main
clinically relevant name, and for which a non-eponymous name is not available or
would be unfamiliar to clinicians.
Hodgkin lymphoma
Burkitt lymphoma
5.1.6 Abbreviations
Principle
5.1.6 Abbreviations
Category
International „gap‟
Status
Approved
Date approved
14/07/10
Review date
01/07/12
Abbreviations are not permitted in the Fully Specified Name (FSN)
Where abbreviations are required in any other type of description then they should
ordinarily be fully expanded in the same text string except in rare circumstances. A
list of exceptions to this rule must be maintained and can be found in Appendix 1
For example
FSN - Computed tomography of brain (procedure)
Pref term - CT of brain
Rather than
Pref term - CT (computed tomography) of brain
Where the abbreviation is an exact word match with the expanded text then the
representation will be the abbreviation followed by a hyphen, followed by the
expanded words, eg
FSN - Intermittent positive pressure ventilation (procedure)
Pref term - IPPV - intermittent positive pressure ventilation
It should be noted that the first word after the hyphen should be lower case as per
usual capitalisation rules.
Where the abbreviation is accompanied by additional text then the abbreviation
should be inserted directly prior to the expanded form which will be in parentheses,
eg
20
FSN Removal of suture from mouth (procedure)
Pref term Removal of suture from mouth
Syn – ROS (removal of suture) from mouth
Abbreviations should never be used without the corresponding expanded form in
the same description (unstated but implied) except in rare circumstances. A list of
exceptions to this rule must be maintained and can be found in Appendix 2.
It is recognised that there are a large number of existing concepts which do not
conform to these rules which will not be addressed in the near term. This does not
mean that the rules should be relaxed for content of this nature even though it may
lead to some apparent inconsistency. For example, the abbreviation IgE will not be
permitted in any new FSNs, despite there being a large number already present in
SNOMED CT (in the FSN). It is permitted for the abbreviation to be incorporated in
the synonym subject to the normal rules above.
5.1.7 Verbal nouns
Principle
5.1.7 Verbal nouns
Category
International „gap‟
Status
Approved
Date approved
14/07/10
Review date
01/07/12
Generally, the usual form for describing the clinical action within a FSN and
preferred term is the verbal noun ending in “-ion” rather than “-ing”.
For example:
Incision” rather than “Incising”
Destruction” rather than “Destroying”
Exceptions:
When no other verbal noun form is available:
Suturing of tricuspid valve (procedure)
When common usage sanctions the noun form:
Cautery of wart (procedure)
Monitoring of drainage tube (procedure)
21
There are a large number of concepts regarding the provision of education or
advice. These should not be expressed as advice given/provided (unless the past
tense is actually required for a particular „situation with explicit context‟ concept.
For a procedure concept, the preferred wording would be „provision of advice about
or education for...‟.
5.1.8 Past and future tense verbal forms
Principle
5.1.8 Past and future tense verbal forms
Category
International „gap‟
Status
Approved
Date approved
14/7/10
Review date
01/07/12
Past or future tense verbal forms must not be used, since they invoke a temporal
context for procedures, indicating that the procedure was done or is to be done.
Existing terms containing past tense verbs will be moved to the context-dependent
hierarchy.
For example:
hand tendon ganglion excised
should instead be phrased:
excision of ganglion of tendon of hand
Other items that are disallowed would include order/instruction forms of words such
as „monitor‟ and „remove‟. Neither should giving/providing (for advice etc) be used,
or the imperative of give or provide.
5.1.9 Language dialects
Principle
5.1.9 Language dialects
Category
UK
Status
Approved
Date approved
7/10/10
Review date
1/10/12
All fully specified names should be represented in the “US” dialect. Preferred terms
and synonyms will always be described in UK English in the UK edition.
For example:
Tumor of endocrine pancreas (disorder)- FSN
Tumour of endocrine pancreas – Preferred_GB
22
Tumour of endocrine pancreas – Synonym_GB
5.1.10 Negation concepts
Principle
5.1.10 Negation concepts
Category
International „gap‟
Status
Approved
Date approved
7/10/10
Review date
1/10/12
Pre-coordinated procedure concepts with a negative context are considered
outside the scope of SNOMED CT, the SNOMED CT context model should be
used to post-coordinate procedure concepts. Findings concepts should be
considered on a case by case basis but not added routinely.
Any exceptions should be escalated for review by the UKTC Edition Committee
The following would therefore not be acceptable:
Hand tendon ganglion not excised
5.1.11 „Either‟/‟or‟ Procedures
Principle
5.1.11 „Either‟/‟or‟ Procedures
Category
International „gap‟
Status
Approved
Date approved
14/07/10
Review date
01/07/12
The use of „either‟ and „or‟ is not permissible within SNOMED CT as it introduces
potential ambiguity. In such circumstances it has been agreed that these
procedures will be represented by two (or occasionally more) concepts within
SNOMED CT. The following would therefore not be permitted.
Repair of total anomalous pulmonary venous connection to coronary sinus
or right atrium
5.1.12 Use of numerics
Principle
5.1.12 Use of numerics
Category
International „gap‟
Status
Approved
23
Date approved
14/07/10
Review date
01/07/12
There are occasions where it is important to use numbers in descriptions.eg,
Ability to walk 10 metres
It has been agreed that it is not necessary to expand the numeric characters into
their alphabetic form. Where existing content includes the textual form then it is
not necessary to make changes.
5.1.13 Character „case‟ conventions
Principle
5.1.13 Character „case‟ conventions
Category
International „gap‟
Status
Approved
Date approved
14/07/2010
Review date
01/07/2012
All terms should be given in lower case letters except the first letter of the first
word in the string, which should be capitalized. Concepts should not include
articles like “an” and “the” in the string.
For example:
Neoplasm of lower respiratory tract (disorder)
Exception: Concepts with the proper names of a person, organization, species or
abbreviations in the string should be properly capitalized.
Angiokeratoma of Fordyce
Neonatal jaundice with Dubin-Johnson syndrome
Organisation names would also be considered an exception where every word of
the name of the organisation would start with a capital letter. This is only necessary
for actual named specific instances of organisations but not any generic
representation, eg:
Northern Ireland Health Board
HC1 requested from health boardTThe former represents a single entity, there is
only one Northern Ireland Health Board, and therefore is the name of a unique
entity. The latter represents a generic entity where there are potentially multiple
health boards.
FFurther examples:
Signing of general practitioner maternity claim by doctor
24
General practitioner out of hours handover form completed
RM10 Department of Social Security regional medical officer report received
Royal Air Force
Seen in general practitioner unit
See section 6.8 for further exceptions to support messaging.
5.1.14 Accented and unusual characters
Principle
5.1.14 Accented and unusual characters
Category
International „gap‟
Status
Approved
Date approved
14/07/10
Review date
01/07/12
SNOMED CT files use UTF-8 encoding (of Unicode character-strings), which
means that the variety of possible characters is large.
The overwhelming majority of English language Descriptions in SNOMED CT can
be created using ASCII characters in the range 32-127, however some additions to
SNOMED CT will require the use of characters above this range – for example
diacritic/accented characters.
If the accented/multi-byte characters are present in the authoritative source
material then these should be added to as many description types as required. If
the accent is present in the requirement it should be included in the FSN at least.
Accent-free synonyms with superficially equivalent characters (e.g. „e‟ for „é‟)
should not routinely be added.
Note: It is not permitted to use the „pipe‟ character (“|”, Unicode +007C) – this
character has special utility in the SNOMED CT Compositional Grammar
(indicating the start and end of term strings), and its use in terms will disrupt
parsing of Expressions represented using this grammar.
5.1.15 „Disorder‟ naming conventions
Principle
5.1.15 „Disorder‟ naming conventions
Category
International „gap‟
Status
Approved
Date approved
14/07/10
Review date
01/07/12
25
In the disorder hierarchy, the word 'disorder‟ in singular should be used. When the
concept is a general grouper of disorders of a body system, body site, or other
broad general category, the word 'disorder' should be used in preference to
'disease' for the FSN. This rule in favour of „disorder‟ over „disease‟ applies only to
broad groupers, and is not applied at „leaf‟ level. Plurals such as 'disorders' or
'diseases' may only be used in synonymous terms for grouper concepts.
Descriptions should avoid the article 'the' in the string
Plurals should never be used in any descriptions except as documented
exceptions.
For example:
Disorder of reproductive system
Disease of lower respiratory system
Disease of nose
Exceptions:Eponymous diseases
Pick‟s disease
Goodpasture's disease
Crohn's disease
5.1.16 Use of hyphen for tagging to identify content designed for a specific
limited use case
Principle
5.1.16 Use of hyphen for tagging
Category
UK
Status
Approved
Date approved
14/07/10
Review date
01/07/12
A tag is a word or words that have previously been added at the end of a
description to identify that the preceding term string is limited to a specific UK NHS
context/use case. It is distinct from the semantic tag at the end of the description
in parentheses. The tag is separated from the main part of the term by „space,
dash, space‟ i.e. „term string – tag (semantic tag)‟. Tagging labelled the concept
for the specific purpose of its use case.
Clinical concepts should not be needlessly qualified by the addition of text that
limits their use beyond the logical meaning that is intrinsic to the concept. By
default, content in a national terminology should be „recyclable‟ for a range of use
cases. It also therefore follows that such content should be supertyped according
to ontological principles rather than grouped to meet an administrative use case
26
SNOMED is designed to be a single coherent ontology. In the past there have
been well intentioned, pragmatic attempts to qualify, with a descriptive tag, content
that is essential to a UK NHS business process but ontologically at odds with
editorial principles. This has led to ontologically isolated „islands‟ of content,
sometimes in logical conflict with content elsewhere. On review, this approach has
been deemed unnecessary because the content can (where it has not been ruled
„out of scope‟) be expressed in ways that makes it clinically valid and logically
analysable.
In the addition of new content; if a procedure or finding etc relates to a specific
programme, care pathway etc then either:
The procedure or finding should stand by itself as a clinically valid concept without
reference to a programme
Example: Measles mumps rubella catch-up vaccination (procedure)
Or
The programme should be added as an integral part of the description (where the
programme is part of the intended meaning not additional to it).
Example: Measles mumps rubella catch-up vaccination programme
enhanced services administration (procedure).
Previous policy would have been for this to be identified with a tag (italics below)‟
because of the association with an enhanced services scheme:
„Measles mumps rubella catch-up vaccination - enhanced services
administration (procedure)‟.
There remains in the terminology some content that is tagged (although note that
not all content that has text following „space, dash, space‟ is tagged). There is a
process of revising this content over time to bring it into line with the above policy.
5.1.17 Authority dependent concepts
Principle
5.1.17 Authority dependent concepts
Category
UK
Status
Date approved
Review date
Many requests are received for highly pre-coordinated content, often associated
with policy initiative or best practice guidance.eg,
Family history of total cholesterol greater than 6.7 millimoles per litre in child
or sibling under 16 years of age
27
This is a risk factor for familial hypercholesteraemia along with a number of other
items and is described in the NICE guidance – see
http://www.nice.org.uk/nicemedia/pdf/CG071NICEGuideline.pdf
Expressions of this nature should be considered in much the same way as
component scores of assessments scales (see section 6.4) in that it is not
necessary to assign a SNOMED code to these complex compound risk factors,
each aspect of the clinical notion could be coded in the record but in terms of its
relationship to the NICE guidance then a composite concept of the following form
should be sufficient;
Familial hypercholesterolaemia Simon Broome criteria NICE 2009 (finding)
5.1.18 Concepts of „classification‟ origin
Principle
5.1.18 Concepts of „classification‟ origin
Category
UK
Status
Approved
Date approved
14/07/10
Review date
01/07/12
There are a number of concepts in the UK extension that are necessary for
completeness of the super-setting of the earlier versions of the Read codes which
require the direct inclusion of concepts from the UK standard classifications (ICD10 and OPCS-4), such as:
Other bronchus operation NOS (procedure)
The inclusion of such non-specific concepts is no longer permitted in SNOMED CT.
Therefore, the use of such inclusion/exclusion expressions such as „other‟, NEC
(not elsewhere classified), NOS (not otherwise specified), OS (otherwise specified)
and EC (elsewhere classified) are not permitted.
28
6 Appendix 1 - Domain-specific editorial principles
6.1 Activities of daily living
Principle
6.1 Activities of daily living
Category
International „gap‟
Status
Date approved
Review date
There are a number of concepts to represent the ability to undertake activities
which are considered typical daily activities.
It is often important to be able to record a statement regarding an individual‟s ability
to do some or all of these things. A simple pattern has been devised to
accommodate the requirements as they are understood.
There are five common required statements which follow the following pattern:
Able to.....
Does
Does not
Difficulty
Unable
Where justification can be provided, this range can be expanded to include the
following additional assertions. The following additional statements are also
permitted when justification can be provided:
Independently able to.....
Able to.... with assistance
Able to.... with aids
Able to.... with aids and assistance
6.2 Religion and religious affiliation
Principle
6.2 Religion and religious affiliation
Category
UK
Status
Approved
Date approved
12/01/10
Review date
01/01/12
29
A need for representation has been identified for both types of concepts, the
religion itself and the identification of an individual as a follower of that religion.
It is important to be able to distinguish between each easily in the fully specified
name.
For the actual religion, the representation is as follows for the FSN:
Lutheran Church (religion/philosophy)
With alternative descriptions such as:
Lutheranism
For the religious affiliation, the pattern for the FSN is:
Lutheran, follower of religion (person)
With an alternative description of:
Lutheran
6.3 UK Administrative concepts
Principle
6.3 UK Administrative concepts
Category
UK
Status
Approved
Date approved
14/07/10
Review date
01/07/12
The former top-level hierarchy for UK administration concepts will be retired from
October 2010. These concepts are largely abstract notions or headings used for
recording something against, eg
Lipid disorder monitoring administration (administrative concept)
The findings that may be associated with these items are typically conventional
concepts, eg
Stop smoking monitoring check done (finding)
There may or may not be suitable procedure concepts which would be required to
determine an administrative status, eg
Alcohol disorder monitoring (regime/therapy)
Any concepts affected will be classified into the various flavours and editorial
principles developed for each.
It should also be noted that some concepts of this type may contravene other
editorial statements such as the use of past tense to demonstrate that a procedure
was confirmed as being done or a finding was deemed to be present, eg the
previously mentioned,
30
Stop smoking monitoring check done (finding)
These concepts will be considered for retirement or placed in the „situations‟
hierarchy.
6.4 Representation of „official‟ forms and certificates in
healthcare
Principle
6.4 „Official‟ forms and certificates
Category
UK
Status
Approved
Date approved
14/07/10
Review date
01/07/12
There are a number of forms and certificates commonly referred to in their
abbreviated form in healthcare including those relating to prescriptions and GP
practice administration.
In the FSN this should ordinarily be expanded to reflect the full meaning of the
abbreviated form. However, this expanded form is not necessary in the pref term or
synonym.
For example:
FSN: Disability living allowance 370 form completed (finding)
Pref term: dLA 370 form completed
Synonym: dLA 370 completed
It is also important to describe whether a „certificate‟ or „form‟ is the subject of the
concept and this word should also be expressed in the FSN for those concepts not
stated as exceptions below, eg:
FSN: BD8 blindness certificate(record artifact)
Pref term: BD8 blindness certificate
Where the name of the form or certificate is actually just a series of characters
(without any relation to a logical expanded form) then they obviously cannot be
expanded and should be listed as exceptions explicitly (in appendix 1) or
referenced.
For example:
FSN: FP34D pay received (finding)
Pref term: FP34D pay received
This will include those forms listed in the „Red book‟ which details the fees and
allowances payable to general medical practitioners in England and Wales which
can be found at http://www.redbook.i12.com/rb/Docs/rb6.htm
31
There is no requirement regarding the position of the word „form‟ (or „certificate‟) in
the text string though ordinarily it would either be positioned immediately after the
abbreviation or at the end of the string, eg
FSN: FP31 general anaesthetic second general practitioner form
FSN: FP31 form general anaesthetic second general practitioner
6.5 Scored Assessments
Principle
6.5 Scored Assessments
Category
UK
Status
Approved
Date approved
13/04/10
Review date
01/04/12
There are a great many assessment scales in use throughout the NHS. Some of
these are used in single organisations and others are used widely. It is not a
priority for the National reference terminology to support every local use case.
Criteria need to be clearly communicated in order for submitters to understand the
requirements for any new content to be included in the UK edition of SNOMED CT
(or the International edition).
Agreed criteria are as follows:
Used in more than one healthcare organisation
Mandated in national clinical guidelines
Consistent format (in line with editorial principles – see below)
Further, it has been agreed that no significant degree of clinical validation is
necessary before a concept is accepted as being of utility in the national
terminology.
Where the submission meets any of the above criteria, for each scale, we will
expect a concept in SNOMED to represent the scale itself (in staging and scales),
a 'procedure' that can be used for the undertaking of the assessment and an
observable for the overall score and potentially sub-scores (but the latter only
where considered clinically significant)
For example:
Berg balance scale (staging and scales)
Berg balance scale score (observable entity)
Assessment using Berg balance scale assessment (regime/therapy)
Where sub-scores are considered clinically significant then the observable and
staging and scale concepts will be added but not the procedure unless this is
undertaken as a separate procedure.
32
Even though the score that we are referring to in the observable may represent a
summation of a number of component scores, unless the score arrived at is named
by the scale developer as a „total‟ score then the concept will not include the word
total in any of the descriptions.
For further information, please refer to policy on the use of assessment scales in
the NHS.
6.6 International Paediatric and Congenital Cardiac Code (IPCCC)
procedures
Principle
6.6 International Paediatric and
Congenital Cardiac Code (IPCCC)
procedures
Category
International „gap‟
Status
Previously approved, under review
Date approved
14/7/10
Review date
Jan 2011
It is recognised that the IPCCC list contains a vast number of complex items.
These items include procedures, findings, devices, qualifiers and post qualifiers.
As the editorial principles upon which the IPCCC long list is constructed is different,
in parts, to those governing SNOMED CT, a proportion of the IPCCC long list
content is unsuitable for addition to SNOMED CT due to the constraints identified
in previous sections.
Those issues that are particular to the IPCCC harmonisation are listed below.
6.6.1 Repair Procedures
The term “repair” will be preferred over the term of “correction”.
The representation will therefore be:
Repair of total anomalous pulmonary venous connection to supracardiac
vessel (procedure)
6.6.2 “Mixed” Vessel Procedures
The term “mixed” is used to describe a mixture of anomalous pulmonary venous
connections and is a well established and frequently used term in paediatric
cardiology. In the mixed form of pulmonary venous connections some veins will go
to one site and others to another and possibly even all 4 to different sites. This
makes it impossible to fully specify vessels. The issue was considered by the
33
IHTSDO who concluded that it was reasonable for the word “mixed” to be used in
an FSN in the case of paediatric cardiology.
6.6.3 Confluence procedures
The word confluence is ambiguous in the context of paediatric cardiac care
procedures, it is more correct to use the term “pulmonary venous confluence”.
eg:
Anastomosis of pulmonary venous confluence to left atrium via connecting
vein (procedure)
6.6.4 Combined Procedures and pre-coordinated IPCCC content
There are pre-coordinated items within the IPCCC list which express a number of
potentially separate procedures within one code. Where individual elements of
these procedures can be broken down into separate meaningful procedure
concepts, this is acceptable. However where two (or more) parts are essential
components of one operation, and where these procedures would not be carried
out in isolation, the advice received from the IHTSDO was that a single new
SNOMED CT concept may be authored to reflect all elements of the IPCCC code.
All new SNOMED CT content will be authored to reflect this decision.
For example:
Repair of total anomalous pulmonary venous connection by coronary sinus
cutback to oval fossa with direct anastomosis of pulmonary venous
confluence (procedure)
Repair of partial anomalous pulmonary venous connection by baffle
redirection to left atrium with systemic vein attached to atrial appendage
(procedure)
6.6.5 Baffle Devices
A number of procedures exist within the IPCCC list that use the term “baffled.”
Clarification has been sought on the exact nature of this term. It has been agreed
to represent the term “baffled” as “insertion of baffle” when authoring new content
for SNOMED CT.
Where a baffle is used as a mechanism to effect a repair then the agreed
representation is 'procedure with baffle...' rather than „procedure and baffling‟ (or
similar).
6.6.6 Additional techniques and sub-procedures
Where a technique or sub-procedure is used within new SNOMED CT content, the
term string construction will use the word “by.”
For example, the IPCCC term:
34
Repair of total anomalous pulmonary venous connection to right atrium
using atrial septum translocation
Will be represented in SNOMED CT as:
Repair of total anomalous pulmonary venous connection to right atrium BY
atrial septum translocation (procedure)
6.7 Diagnostic Imaging procedures
Principle
6.7 Diagnostic Imaging procedures
Category
International „gap‟
Status
Approved
Date approved
14/07/10
Review date
01/07/12
Almost all imaging procedures can be unambiguously expressed in a number of
ways and there is a balance to be struck between allowing flexibility in language
use and efficient terminology maintenance so all variants for all modalities will not
routinely be included in SNOMED CT – any over and above those optimal
descriptions following must be justified explicitly.
As a minimum, procedures will ordinarily be expressed in terms of the modality and
body site (represented as „X‟ in the following illustrations).
6.7.1 X-ray imaging
Descriptions:
FSN: X-ray of X (procedure)
PT: X-ray of X
Note – no further synonyms should routinely be considered except in the case of
mammography, where an additional synonym of mammogram is considered
useful:
Descriptions:
FSN: X-ray of breast (procedure)
PT: X-ray of breast
Synonym: Mammogram
Note - The notion of „plain X-ray‟ is considered ambiguous as it is unclear what it is
that is considered „plain‟?.
35
6.7.2 Computed tomography
Descriptions:
FSN: Computed tomography of X
PT: CT of X
Computed tomography angiography
Descriptions:
FSN: Computed tomography angiography of X (procedure)
PT: CT angiography of X
Synonym: CT angiogram of X
Computed tomography arthrography
Descriptions:
FSN: Computed tomography arthrography of X (procedure)
PT: CT arthrography of X
Synonym: CT arthrogram of X
Computed tomography venography
Descriptions:
FSN: Computed tomography venography of X (procedure)
PT: CT venography of X
Synonym: CT venogram of X
Note – the convention of describing these as Computerised Axial Tomography has
ceased to be accurate clinical parlance due to the many alternative techniques to
create images in multiple planes/axes.
6.7.3 Ultrasonography
Descriptions:
FSN: Ultrasonography of X (procedure)
PT: Ultrasonography of X
Synonym: Ultrasound scan of X
Doppler ultrasonography
Descriptions:
36
FSN: Doppler ultrasonography of X (procedure)
PT: Doppler ultrasonography of X
Synonym: Doppler ultrasound scan of X
Note - Obstetric ultrasound scans are more complex to describe and often much
additional clinical information needs to be described. However in terms of the
modality the same rules are applied as follows:
Obstetric ultrasonography
Descriptions:
FSN: Obstetric ultrasonography of X (procedure)
PT: Obstetric ultrasonography of X
Synonym: Obstetric ultrasound scan of X
6.7.4 Magnetic resonance imaging procedure
Descriptions:
FSN: Magnetic resonance imaging of X (procedure)
PT: MRI of X
Magnetic resonance angiography
Descriptions:
FSN: Magnetic resonance angiography of X (procedure)
PT: Magnetic resonance angiography of X
Synonym: Magnetic resonance angiogram of X
Magnetic resonance venography
Descriptions:
FSN: Magnetic resonance venography of X (procedure)
PT: Magnetic resonance venography of X
Synonym: Magnetic resonance venogram of X
Magnetic resonance arthrography
Descriptions:
FSN: Magnetic resonance arthrography of X (procedure)
PT: Magnetic resonance arthrography of X
37
Synonym: Magnetic resonance arthrogram of X
6.7.5 Radionuclide imaging (Nuclear medicine)
Descriptions:
FSN: Radionuclide scan of X (procedure)
PT: Radionuclide scan of X
Synonym: Radioisotope scan of X
Note - Where it is important to represent a particular isotope and associated agents
in the concept then the descriptions will be as follows:
Descriptions:
FSN: Radionuclide scan of X using Y (procedure)
PT: Radionuclide scan of X using Y
Synonym: Radioisotope scan of X using Y
6.7.6 Positron emission tomography
Descriptions:
FSN: Positron emission tomography of X (procedure)
PT: Positron emission tomography of X
Synonym: PET of X
6.7.7 Single photon emission computed tomography
Descriptions:
FSN: Single photon emission computed tomography of X (procedure)
PT: Single photon emission computed tomography of X
Synonym: SPECT of X
6.7.8 Fluoroscopy imaging
Descriptions:
FSN: Fluoroscopy of X (procedure)
PT: Fluoroscopy of X
38
Note - Simple Fluoroscopy is the real time imaging, usually on TV monitors, of a
body part or system and is only rarely undertaken as an imaging process alone
(without use of contrast or some interventional procedure), most commonly
fluoroscopy is used to guide or direct the primary procedure or purpose. The
convention in clinical practice is largely to ignore the fluoroscopic element and refer
to a procedure entirely by the primary component, eg angiography, however this
would be unacceptable in SNOMED CT where the imaging component must be
explicitly described, at least in the FSN. The convention is to use the adjectival
form rather than the noun.
Fluoroscopic angiography
Descriptions:
FSN: Fluoroscopic angiography of X (procedure)
PT: Fluoroscopic angiography of X
Synonym: Fluoroscopic angiogram of X
Fluoroscopic venography
Descriptions:
FSN: Fluoroscopic venography of X
PT: Fluoroscopic venography of X
Synonym: Fluoroscopic venogram of X
Fluoroscopic arthrography
Descriptions:
FSN: Fluoroscopic arthrography of X (procedure)
PT: Fluoroscopic arthrography of X
Synonym: Fluoroscopic arthrogram of X
Note – existing content where the modality is not expressed should be considered
as some type of imaging rather than implicitly as fluoroscopic (as was their
probable initial intent). As such they are not representative of any actual procedure
performed in the real world but may have some utility as grouper concepts.
6.7.9 Dual energy X-ray photon absorptiometry
Descriptions:
FSN: Dual energy X-ray photon absorptiometry of X (procedure)
PT: Dual energy X-ray photon absorptiometry of X
Synonym: DXA of X
39
Synonym: DEXA of X
Note, the word scan is superfluous in the majority of instances where it might be
used (CT, MRI) except in ultrasound where it is can be used to differentiate
diagnostic imaging procedures from therapeutic treatment procedures.
6.7.10 Multiple modality procedures
There are very few imaging procedures which could be truly considered to be
multi-modality procedures, on most occasions two procedures can be considered
to be conducted in parallel rather than as one. There are, however, a couple of
instances where this is the case, and the images are produced by one piece of
equipment by a single (possibly) operator, albeit with multiple imaging energies,
these are PET/CT and SPECT/CT.
These will be represented as follows:
Single photon emission computed tomography with computerised tomography
Descriptions:
FSN: Single photon emission computed tomography with computerised
tomography
of X (procedure)
PT: Single photon emission computed tomography with computerised
tomography of X
Synonym: SPECT CT of X
Positron emission tomography with computerised tomography
Descriptions:
FSN: Positron emission tomography with computerised tomography of X
(procedure)
PT: Positron emission tomography with computerised tomography of X
Synonym: PET CT of X
6.7.11 Imaging guided procedures
There are numerous procedures where the imaging component can be considered
to be a supplemental or secondary technique to assist with the accomplishment of
the primary goal.
The primary focus will be reflected in the pattern of term construction for the fully
specified name although the alternative pattern in the preferred term has been
confirmed by a representative group as being equivalent and more intuitive to
users. The general pattern for the FSN for all modalities would be:
40
Y (procedure) + using + DI Modality + guidance (for FSN)
And specifically, for each „guidance‟ modality in turn:
Computed tomography guided procedure
Descriptions:
FSN: Y using computed tomography guidance (procedure)
PT: CT guided Y
Fluoroscopy guided procedure
Descriptions:
FSN: Y using fluoroscopic guidance (procedure)
PT: Fluoroscopy guided Y
Magnetic resonance imaging guided procedure
Descriptions:
FSN: Y using magnetic resonance imaging guidance (procedure)
PT: MRI guided Y (procedure)
Ultrasonography guided procedure
Descriptions:
FSN: Y using ultrasonographic guidance (procedure)
PT: Ultrasonography guided Y
Syn: Ultrasound guided Y
X-ray guided procedure
Descriptions:
FSN: Y using X-ray guidance (procedure)
PT: X-ray guided Y
6.7.12 Contrast
It is essential to express when contrast is part of a procedure and that descriptions
are constructed consistently, for example:
41
Descriptions:
FSN: Computerized axial tomography of brain with radiopaque contrast
(procedure)
PT: Computerized axial tomography of brain with radiopaque contrast
CT brain with contrast
Synonym: CT of brain with contrast
6.7.13 View/Projection/Technique adjustments
It can be important both clinically and from an administrative perspective that
variations in technique from the norm are captured, not least so that images can be
both acquired and interpreted correctly. Examples of modifications include:
Axial
Skyline
Decubitus
Weight-bearing
Penetrated
Stress views
Soft tissue
Paediatric
Though these exist as potential qualifying values within SNOMED CT, they are not
presently allowable values for post-coordination of DI procedures.
6.8 Messaging content
Due to the nature of this type of concept they are very often subject to different
editorial rules to the general corpus of SNOMED CT.
Theses exceptions are listed in this section
6.8.1 FFocusActOrEvent Concepts
Principle
6.8.1 FocusActOrEvent codes
Category
UK
Status
Approved
Date approved
14/07/10
Review date
01/07/12
42
These concepts are used to support HL7 v3 messaging and identify actual
messages being sent. Eg “Discharge from Inpatient Care”
The concept is used to identify the document which is used to convey details of an
encounter back to a GP or other Healthcare practitioner.
It would take the form:
Diagnostic Imaging Request Event
With each word being capitalised. This would be an exception to the general
capitalisation rules
NB – these concepts were formerly tagged with an indication of the use case, eg:
Diagnostic Imaging Request Event – FocusActOrEvent
This is now no longer the case for new content.
6.8.2 Document types
Principle
6.8.2 FocusActOrEvent codes
Category
UK
Status
Approved
Date approved
14/07/10
Review date
01/07/12
It has been required to introduce an additional unexpanded abbreviation (not
permitted for general concepts) for the purposes of messaging specific document
types, specifically:
•
Outpatient Clinic Attendance - GP Letter
Where „GP‟ means General Medical Practitioner.
6.9 Diabetes
Principle
6.9 Diabetes
Category
UK
Status
Approved
Date approved
14/07/10
Review date
01/07/12
There is a discrepancy on the use of the Arabic or Roman numeral in the
representation of type one and type two diabetes in all description types.
The principle will be to use the Roman numeral in the FSN and preferred term with
an alternative description containing the Arabic alternative.
43
This is in line with ICD-10 conventions.
6.10 Levels of risk – pre-coordination
Principle
6.10 Levels of risk
Category
UK
Status
Approved
Date approved
13/01/11
Review date
13/01/13
There is a clinical requirement to express stratified levels of risk in many clinical
domains. The stratification often differs due to different clinical perspectives or
requirements. In order to support these requirements the UK extension will contain
those patterns that are represented in official guidance from such bodies as NICE
and clinical professional organisations such as the Royal College of Physicians.
Other patterns will not be represented routinely and must be brought before the
UKTC Edition Committee. Those patterns accepted are:
High risk of activity intolerance
Moderate risk of activity intolerance
Low risk of activity intolerance
Higher risk drinking
Increasing risk drinking
Lower risk drinking.
6.11 Nature and number of invitations – eg to screening
Principle
6.11 Nature and number of invitations –
eg to screening
Category
UK
Status
Approved
Date approved
13/01/11
Review date
13/01/13
There are a number of patterns of representation which have been supported over
many years which include the pre-coordination of invitation type (eg letter,
telephone call etc) with the number of the invitation (eg 1st, 2nd, 3rd etc).
44
These are important for the business processes that are used for call/recall for
patients and also an important record for audit purposes that invitations have
actually been issued.
With the advent of new communication technologies (email, SMS text), this
representation was reviewed. The UKTC Edition Committee agreed to support the
persistence of these representations but agreed that a withdrawal strategy should
be put in place.
Examples of currently permitted patterns are as follows:
human papillomavirus vaccination invitation first letter
learning disability annual health check telephone invitation
human papillomavirus vaccination invitation third short message
service text message sent
6.12 “On examination” and “complaining of” concepts
Principle
6.12 “On examination” and “complaining
of” concepts
Category
UK
Status
Approved
Date approved
13/01/11
Review date
13/01/13
There may be occasions when findings need to be differentiated by how they were
determined, ie whether reported by the patient themselves or whether discovered
as a result of a physical examination. These concepts are clinically justified in
some cases but there is no need to add an equivalent C/O and O/E for every
regular „finding‟ concept. It was agreed that there should be no rule barring the
introduction of any new concepts but that each submission should be directed to
the UKTC Edition Committee for approval. Examples of concepts approved for
addition to the UK extension include:
On examination - scrotal swelling (finding)
Complaining of scrotal swelling (finding)
In addition to the „regular‟:
Scrotal swelling (finding)
6.13 Findings of assessments/treatments and previous treatments
45
Principle
6.13 Findings of
assessments/treatments and previous
treatments
Category
UK
Status
Approved
Date approved
13/01/11
Review date
13/01/13
It is sometimes more convenient/efficient to record the outcome of some form of
assessment instead of or in addition to the procedure concept relating to the
conduction of the assessment.
Some systems may also not have the capacity to combine the result of an
assessment with the procedure for conduction of the assessment.
WWhere requests are received for a combined concept then certain patterns are
permissible and include:
Mental health assessment – no abnormalities detected
Physical health assessment normal
Differing representations should be referred to the UKTC Edition Commmittee
Similar requests for recording the effectiveness (or not) of previous treatments
would not be permissible, eg:
Previous oedema treatment effective
Previous oedema treatment ineffective.
It is not clear from these descriptions whether these statements apply to all
previous treatments or only some and are more like audit queries than entries for
patient records.
6.14 “History of”, “no history of”, “family history of” and “no
family history of” (finding)
Principle
6.14 “History of”, “no history of”, “family
history of” and “no family history of” (finding)
Category
UK
Status
Approved
Date approved
13/01/11
Review date
13/01/13
46
Whilst it is recognised that the design of SNOMED CT supports the postcoordination of these types of concept or that systems architecture may provide an
alternative solution, many systems currently need these to be pre-coordinated.
Not all findings will need equivalent history of (and no history of) representations
but when these are requested they will be added to the UK edition. However, only
those that can be modelled and have equivalent post-coordinated forms will be
permissible.
For instance the following are acceptable:
History of autosomal dominant diabetes mellitus
No history of renal disease
No lipodystrophy
And the following would not be:
History of oedema not responsive to therapy
The same methodology would be applied to any requested family history of
concepts.
6.15 Inclusion of drug/vaccine name in procedures
Principle
6.15 Inclusion of drug/vaccine names in
procedures
Category
UK
Status
Approved
Date approved
13/01/11
Review date
13/01/13
The convention is not to use drug names in drug administration type procedure
concepts, for instance:
•
typhus vaccination (procedure)
•
injection of sclerosing agent in varicose vein (procedure)
•
continuous infusion of chemotherapy
One of the rationales behind this proposal is that specific drug information should
be available from the medication record where it is a prescribable item.
There are a number of drugs which are not normally prescribed in the conventional
way such as vaccines. It has been agreed that it is permissible to include the virtual
therapeutic moiety or virtual medicinal product (generic) representation of the
vaccine name and/or name of the drug for these concepts, eg:
•
Quadrivalent HPV vaccine
•
Bolus insulin therapy
47
•
Injection of vitamin D
However, the proprietary name of the drug is not permitted so the following would
not be allowed, eg
•
Lispro bolus insulin therapy
6.16 Record headings/items against which a value or text may be
assigned
Principle
6.16 Record headings/items against
which a value or text may be assigned
Category
UK
Status
Pending
Date approved
Review date
Historically a great number of concepts have been added which enable records to
be structured and for values or text to be associated with headings. These have
been incorporated into SNOMED CT as observables or record artefacts. Common
acceptable patterns are as follows:
Interpretation of radiology
Reason for discharge
Contraceptive method status
Evening meal routine
It is noted that there are particular problems with headings referring to dates and they
could be considered ambiguous, eg
Date of last sexual intercourse
Date of referral
Concepts of this nature should be brought to the UKTC Edition Committee
6.17 Concepts relating to actions undertaken as part of specific
legislation
Principle
6.17 Concepts relating to actions
undertaken as part of specific legislation
Category
UK
48
Status
Approved
Date approved
13/01/11
Review date
13/01/13
The permitted format for concepts of this type are as follows:
•
Verb +/-<service>+/-<section> act date
For example
•
Referral to child protection service under section 47 of Children Act 1989.
It has been further agreed that for synonyms the word order can be adjusted to suit
other common patterns, eg
•
PT Removal of patient by transfer direction to prison or other institution
under Section 51 of the Mental Health Act 1983 (England and Wales)
•
SYN S51 MHA (Section 51 Mental Health Act)- Removal of patient by
transfer direction to prison or other institution under Section 51 of the Mental
Health Act 1983 (England and Wales)
6.18 Pre-coordination of laterality
Principle
6.18 Pre-coordination of laterality
Category
UK
Status
Pending
Date approved
Review date
There are as yet no known use cases for the coding of pre-coordinated laterality in
any system processes – there is no compelling evidence that this approach is
superior to using free text or system functionality to represent the laterality.
Therefore any request for pre-coordination should be brought to the Ed Comm with
clear strong justification why these should be added in this form. The current policy
is therefore not to allow the pre-coordination of laterality
49
7 Appendix 2 – UK approved abbreviations
Principle
7 approved abbreviations
Category
UK
Status
Approved
Date approved
14/07/10
Review date
01/07/12
The following abbreviations are considered to be well understood across the whole
clinical community in the UK and do not require accompaniment by the expanded
form in any description but the FSN.
CT – Computed tomography
MRI – Magnetic resonance imaging
NHS – National Health Service
O/E – on examination
H/O – history of
C/O – complaining of
IgE – Immunoglobulin E
PET – Positron emission tomography
SPECT - Single photon emission computed tomography
DXA (DEXA) - Dual energy X-ray absorptiometry
PET CT - Positron emission tomography computed tomography
SPECT CT - Single photon emission computed tomography computed tomography
IgG - Immunoglobulin G
IgM - Immunoglobulin M
IgA - Immunoglobulin A
FH - Family history
RAST - Radioallergosorbent
50