1 Introducción

1.1 Generalidades

La terminología SNOMED CT provee un lenguaje común y un medio consistente para indizar, almacenar, recuperar y agregar datos clínicos de diferentes especialidades y ámbitos de atención de la salud.

SNOMED International mantiene el diseño técnico y la arquitectura de la terminología, y el contenido de su núcleo (que incluye las tablas de conceptos, de descripciones, de relaciones y de historial, así como referencias cruzadas a la CIE) y  la documentación técnica relacionada.

1.2 Propósito

Este documento presenta una breve descripción de los cambios realizados en el contenido de la Edición Internacional de SNOMED Clinical Terms® (SCT) de enero de 2017.

También incluye anotaciones técnicas que detallan algunos problemas conocidos del contenido o aspectos técnicos con causas identificadas pero cuya solución aún no se ha implementado.

Este documento está disponible junto con la Edición en Castellano correspondiente a abril de 2017.

Este documento está escrito para los fines mencionados anteriormente y no incluye detalles sobre las especificaciones técnicas para SNOMED CT ni abarca cada cambio realizado durante la publicación.

1.4 A quién se dirige este documento

Este documento está dirigido a los Centros Nacionales, Centros Colaboradores de la OMS-FCI, proveedores de historias clínicas electrónicas, desarrolladores de terminologías y administradores que deseen conocer los cambios incorporados a la Edición en Castellano de SNOMED CT de abril de 2017.

2 Actividad de desarrollo de contenido

2.1 Resumen

La mejora continua de la calidad y del contenido existente se basa en las solicitudes recibidas a través del Sistema de Presentación de Solicitudes (SPS). La Edición Internacional de enero de 2017 continuó el trabajo impulsado por las contribuciones del proyecto de Terminología Médica Convergente de Kaiser Permanente (CMT), la Agencia Global Medical Device Nomenclature Agency (GMDNA, Nomenclatura Global de Dispositivos Médicos) y Orphanet para agregar nuevo contenido a SNOMED CT. Además, proyectos prioritarios identificados por los miembros dieron lugar a mejoras en la jerarquía de anatomía, mientras que otros cambios igualmente impulsados por proyectos se reflejaron en numerosas modificaciones que incluyeron nuevos agregados y mejoras al contenido existente y que se detallan más adelante.

2.2 Mejora en la calidad del contenido

• En total: se crearon 5123 nuevos conceptos y se realizaron otros 13899 cambios a conceptos existentes. 

  
  

2.2.1 Anatomía 

2.2.1.1 Lateralidad

Para respaldar sistemas que por el momento no pueden implementar la poscoordinación, el Grupo Consultivo Editorial (EAG) aprobó la aceptación de solicitudes de pre-coordinación de conceptos con lateralidad. 

• • Se agregaron conceptos lateralizados como se detalla  a continuación:

1. 1. 1. Más de 250en la jerarquía de conceptos anatómicos y
      2. 400 en las jerarquías de trastornos y procedimientos

2.2.1.2 Estructura/Como un todo/Parte

• • Se mejoraron las convenciones editoriales para apoyar el modelo Estructura/Como un Todo/Parte (SEP) para resolver la ambigüedad potencial entre los conceptos con 'estructura' y con 'como un todo'. Todas las descripciones de conceptos descendientes del concepto 'parte del cuerpo [como un todo] (estructura corporal)' deben contener la frase [como un todo].

1. 1. 1.  Se inactivaron más de 9.000 descripciones sin [como un todo] y
      2. Se agregaron más de 3.600 nuevas descripciones para facilitar la búsqueda

• 23 nuevos conceptos relacionados con nutrición y dietética para apoyar la documentación clínica, la planificación de la atención y la investigación nutricional. 
• 45 nuevos conceptos relacionados con hallazgos de laboratorio para apoyar áreas de microbiología, bioquímica y anatomía patológica

2.2.3 Terminología Médica Convergente (CMT)

• Se agregaron 619 para la edición de enero de 2017, actualizando dominios de Cardiología, Oftalmología y Radiología.

2.2.4 Procedimientos de diagnóstico por imágenes

• Se agregaron 10 nuevos conceptos, correspondientes a tomografía computarizada de energía doble (procedimiento) y subtipos de localizaciones corporales específicas 

2.2.5 Functioning

• Disambiguation of the "Interpretation value (qualifier value)" hierarchy, with correction of approximately 600 findings using this as a target for an attribute

2.2.6 Disorders

2.2.6.1 Orphanet

• • As a result of collaboration with Orphanet (http://www.orpha.net/consor/cgi-bin/index.php) 700 new concepts have been created to represent rare diseases in the disorder hierarchy.

2.2.6.2 ICD-11 Harmonization plan

• • 1200 ICD-11 concepts added from the Mortality and Morbidity Linearization

2.2.7  LOINC

• 215 new concepts among the substance, Techniques, body structure hierarchies added to support antibody, antigen, DNA and RNA components needed to map to LOINC Parts. 

2.2.8 Observables

• Fully modelled more than 150 physiological measurement concepts (body temperature, respiratory rates, heart rates, blood pressure) based on the IHTSDO-979 Vital Signs Observables Inception/Elaboration document. 
• Created 10 required, metadata, attribute and range concepts in different hierarchies

2.2.9 Organisms

• 250 concepts to support microbiology reporting.

2.2.10 Physical objects

•  Concepts representing test kits were relocated from the Substance hierarchy to the Physical object hierarchy. Because the meaning of the concept was not changed, the concept IDs were retained. Duplicates were resolved; new FSNs were created. 
   

• Over 300 concepts with redundant IS A relationships were revised to remove redundancy
• Combined/compound allergy concepts inactivated as ambiguous
• Drug indicated (situation)| sub-hierarchy reviewed and modeling updated.
• Inactivated disjunctive substance concepts
• Created around 10 required metadata, attribute and range concepts in different hierarchies.

2.4 SNOMED CT derived products

2.4.1 ICD-10 map

The SNOMED CT to the International Statistical Classification of Diseases and Related Health Problems, Tenth Revision (© World Health organisation 1994) 2010 Version map (SNOMED CT to ICD-10 Map) is included in the SNOMED CT International release as a Baseline. The SNOMED CT to ICD-10 Map was created to support the epidemiological, statistical and administrative reporting needs of IHTSDO member countries and WHO Collaborating Centres.

The SNOMED CT to ICD-10 Map is released in Release Format 2 (RF2) only. It is located in the file der2_iisssccRefset_ExtendedMapFull_INT_20170131.txt, which is in the Map folder under Refset, in each of the three RF2 Release Type folders.

The SNOMED CT to ICD-10 Map is released as Refset 447562003 |ICD-10 complex map reference set (foundation metadata concept)|.

2.4.1.1 Content development activity summary

The map is a directed set of relationships from SNOMED CT source concepts to ICD-10 target classification codes.  The SNOMED CT source domains for the MAP are limited to subtypes of 404684003 |clinical finding|, 272379006 |event| and 243796009 |situation with explicit context|.  The target classification codes are ICD-10 2010 release.

2.4.1.2 Mapped content for January 2017

The map provided for the January 2017 release has been updated, and now represents a complete map from SNOMED CT International release to ICD-10 2010 version.

• 315 new concepts added

We would welcome feedback on any issues that users of the map may detect when using the map. Issues should be submitted via mapping@ihtsdo.org

parte del cuerpo [como un todo] (estructura corporal)

3 Technical notes

3.1 Known Issues

Known Issues are content or technical issues where the root cause is understood, and the resolution has been discussed and agreed but has yet to be implemented.  This can be due to a number of reasons, from lack of capacity within the current editing cycle, to the risk of impact to the stability of SNOMED CT if the fix were to be deployed at that stage in the Product lifecycle.  

For the Snomed CT January 2017 International edition, the following Known Issues were identified, and agreed to be resolved in the next editing cycle (to be published in July 2017):

3.2 Resolved Issues

Resolved issues are Known Issues which were not fixed as part of the previous release lifecycle, but which have now been resolved in the latest release - in this case the January 2017 International Edition.  They can also be issues found during the Alpha and Beta testing of the current release, which were resolved before the final deployment of the associated Member release.  Finally they can be issues which were reported or found during the testing phase, but which have been closed without any action taken.  

The Resolved Issues for the Snomed CT January 2017 International edition can be found here:

3.3 Technical updates

3.3.1  RF1 package

In line with the RF1 deprecation plan approved by the General Assembly in October 2015, SNOMED International has now removed the RF1 files from the International Edition release package.

There is a new open sourced program available from SNOMED International (under an Apache v2 open source license) that allows for an algorithmic derivation of RF1 files from the authoritative RF2 distribution.  This is available from Github here: https://github.com/IHTSDO/rf2-to-rf1-conversion

3.3.2  RF2 package naming convention

The naming convention of the RF2 package zip file has been improved, in order to reflect the version of the release package, within the existing Product name/Release Date version standard, as follows:

SnomedCT_[Product][Format(optional)]_[Release Status]_[Release date/time]

This format includes all of the additional information required to quickly and uniquely identify the correct package to use at any one time, without adversely impacting any of the related policies (such as the Snomed CT URI standard, etc).

3.3.3  Release Notes location

The Release Notes file has been removed from the zip file containing the main release package, and is now available as a separate file to be downloaded from the same MLDS version as the International Release package.  This is available from the “January 2017 v1.0” version in the “SNOMED CT International Edition” project, which can be found on the “IHTSDO Releases” page in MLDS, accessed here: 

https://mlds.ihtsdotools.org/#/ihtsdoReleases

3.3.4  Resource File location

The Stated Relationship to OWL resource file has been removed from the zip file containing the main release package, and is now available as a separate file to be downloaded from the same MLDS version as the International Release package.  This is available from the “January 2017 v1.0” version in the “SNOMED CT International Edition” project, which can be found on the “IHTSDO Releases” page in MLDS, accessed here: 

https://mlds.ihtsdotools.org/#/ihtsdoReleases

3.3.5  New refset added to the RF2 package

This refset is a "Lateralizable body structure reference set" (SCTID: 723264001), and has the following attributes:

• It is a Simple Refset 
• It can be used as a normal RF2 refset 
• It only shows concepts which have not yet been lateralised in SNOMED CT but which could be in future, and is not a complete set of Laterality concepts
• It will also be used by the RF1 conversion package in order to use the laterality content in the conversion to RF1 
• It has been added to the existing Simple Refset file in the International edition package (der2_Refset_SimpleSnapshot_INT_20170131.txt)

3.3.6  RF2 package format

For future reference, the RF2 package convention dictates that it contains all relevant files, regardless of whether or not there is content to be included in each particular release.  Therefore, the package contains a mixture of files which contain both header rows and content data, and also files that are intentionally left blank (including only a header record).  The reason that these files are not removed from the package is to draw a clear distinction between

1. ...files that have been deprecated (and therefore removed from the package completely), due to the content no longer being relevant to RF2 in this or future releases, and 
2. ...files that just happen to contain no data in this particular release (and are therefore included in the package but left blank, with only a header record), but are still relevant to RF2, and could therefore potentially contain data in future releases.

This allows users to easily distinguish between files that have purposefully been removed or not, as otherwise if files in option 2 above were left out of the package it could be interpreted as an error, rather than an intentional lack of content in that release.

3.3.7  Early visibility of impending change in the July 2017 International edition

In 2009 the General Assembly decided that from April 26 2017 SNOMED International would no longer license the use of SNOMED antecedent works. See http://www.ihtsdo.org/snomed-ct/what-is-snomed-ct/previous-versions-of-snomed-ct.

In line with this decision, SNOMED International will stop publishing SNOMED RT codes for new SNOMED CT concepts after the January 2017 release. As of the July 2017 release, SNOMED International will also remove the SNOMED RT reference set (900000000000498005 |SNOMED RT identifier simple map (foundation metadata concept)|) from the Simple Reference set file in the International Edition.

SNOMED International again strongly urges users of these antecedent versions to migrate to SNOMED CT as soon as possible.  If anyone wishes to use the RT refset purely for migration purposes, SNOMED International will therefore host a static, non-maintained version (based on the January 2017 content) in a package to be hosted here in MLDS: https://mlds.ihtsdotools.org/#/viewReleases/viewRelease/5376