Document Library

The document library provides access to all NCTS documentation, presentations and webinars related to the understanding, use, adoption and implementation of Australian clinical terminology products. The different types of readerships are categorised as follows.

  • Introductory, Webinars and Release Notes: all users;
  • Business: those involved in setting policies or strategic directions, making decisions about the implementation, purchase or design of electronic health record systems or the use of terminologies and information models in healthcare systems;
  • Clinical: those involved in direct patient care or involved with the implementation of terminology content from a health record or clinical perspective. These individuals provide clinical domain expertise to the specifications of data or value sets; and
  • Technical: individuals designing, building or maintaining electronic health record systems or implementing terminologies or information exchange processes within a system.

Only the latest version of each document is available for download. If you require an older version, please complete the online Support Request form or email help@digitalhealth.gov.au.

By operation of the Public Governance, Performance and Accountability (Establishing the Australian Digital Health Agency) Rule 2016, on 1 July 2016, all the assets and liabilities of NEHTA will vest in the Australian Digital Health Agency. In this website, on and from 1 July 2016, all references to “National E-Health Transition Authority” or “NEHTA” will be deemed to be references to the Australian Digital Health Agency.

/library/DH_2407_2016_AMT_FactSheet_v2.1.pdfAMT Fact SheetA high level overview of the AMT presented as a printable 2-page handout.#00#Introductory|#06#All Documents
/library/DH_2400_2016_AustralianNationalTerminologyLicenceAgreement_v20160809.pdfAustralian National Terminology Licence Agreement The licence terms and conditions for the use of the Australian National Terminology comprising SNOMED CT-AU, the AMT and any other national extensions or derivatives.#00#Introductory|#06#All Documents
/library/DH_2799_2018_Introduction_to_AMT_Presentation_v1.2.pdfIntroduction to AMT presentation v1.2This presentation accompanies the “Introduction to AMT webinar”. Topics include an overview of the AMT, its structure and coverage, purpose, use cases and more.#00#Introductory|#06#All Documents
/library/DH_2798_2018_Introduction_to_SNOMEDCT-AU_Presentation_v1.2.pdfIntroduction to SNOMED CT-AU Presentation v1.2This presentation accompanies the “Introduction to SNOMED CT-AU webinar”. Topics include an overview of SNOMED CT-AU, its structure and content, purpose, use cases and more.#00#Introductory|#06#All Documents
/library/DH_3242_2020_Mapping_to_SNOMEDCT-AU_using_SnapperMap_v1.1.pdfSnapper:Map – creating maps to SNOMED CT-AU Presentation v1.1Demonstrates a tool that enables the creation of maps between SNOMED CT-AU (including the AMT) and other data sources. #00#Introductory|#06#All Documents
/library/DH_2371_2016_RCPA-PathologyTerminologyandInformationModels_TermsofUse_v1.0.pdfRCPA Pathology Terminology and Information Models Terms of Use v1.0This document contains the Terms of Use for users downloading the RCPA Pathology Terminology and Information Models.#00#Introductory|#06#All Documents
/library/DH_3241_2020_Searching_SNOMEDCT-AU_using_Shrimp_v1.1.pdfShrimp terminology browser – searching SNOMED CT-AU presentation v1.1Demonstrates a popular terminology browser and how to search for SNOMED CT-AU content, including the AMT #00#Introductory|#06#All Documents
/library/DH_2502_2017_IHTSDO_Affiliate_License_Agreement_UK_20170101_v1.0.pdfSNOMED CT Affiliate License AgreementThe licence terms and conditions for use of SNOMED CT.#00#Introductory|#06#All Documents
http://snomed.org/vendorintroSNOMED CT Introduction for Vendors (SNOMED International)An informative practical introduction to SNOMED CT focused primarily on the needs of vendors and developers of EHRs and other related applications in healthcare information technology.#00#Introductory|#06#All Documents
http://snomed.org/starterSNOMED CT Starter Guide (SNOMED International)The best place to start learning about SNOMED CT or to refresh existing knowledge. An overview of a range of topics related to the terminology.#00#Introductory|#06#All Documents
/library/DH_2671_2018_SNOMEDCT-AU_and_AMT_Adoption_Infographic_v1.0.pdfSNOMED CT-AU and AMT Adoption InfographicThis document provides a snapshot view of the current terminology-enabled systems, and those in progress around Australia.#00#Introductory|#06#All Documents
/library/DH_3191_2020_SNOMEDCT-AU_and_AMT_subsets_presentation_v1.0.pdfSNOMED CT-AU and AMT Subsets Presentation v1.0This presentation provides an overview of SNOMED CT-AU and AMT subsets and why they are useful in terminology implementations. Examples of NCTS subsets available in different formats (SNOMED CT reference set, FHIR® ValueSet), the use cases they support, and how to access them will be discussed.
This accompanies the SNOMED CT-AU and AMT subsets webinar.
#00#Introductory|#06#All Documents
/library/DH_2797_2018_SNOMEDCT-AU_hierarchies_presentation_v1.0.pdfSNOMED CT-AU hierarchies presentation v1.0This presentation accompanies the “SNOMED CT-AU hierarchies webinar”. Topics include the content available within each of the SNOMED CT-AU hierarchies.#00#Introductory|#06#All Documents
/library/DH_3288_2020__TerminologyAndClassificationPresentation_v2.1.pdfTerminology and Classification Presentation v2.1This presentation was developed in collaboration with the Australian Institute of Health and Welfare (AIHW) and Independent Hospital Pricing Authority (IHPA) and provides an overview of commonly used code sets in health; SNOMED CT-AU features and main use cases; ICD-10-AM features and main use cases; International Classification of Diseases revision; and maps between SNOMED CT and ICD-10.#00#Introductory|#06#All Documents
https://www.youtube.com/watch?v=r_65SW23hH0&feature=youtu.beBasic FHIR terminology services webinar“The third of three 1-hour introductory technical webinars Topics include: a recap of the structure of CodeSystem, ValueSet and ConceptMap resources and basic FHIR SCRUD actions (Search, Create, Read, Update and Delete); specific terminology operations including lookup, subsumes, expand, validate-code, translate and closure; various terminology use cases and applicable operations; tips and hints.”#01#Webinars|#06#All Documents
https://www.youtube.com/watch?v=Ht5F2JdZlCA&abTerminology and Classification webinar v1.0This webinar was developed in collaboration with the Australian Institute of Health and Welfare (AIHW) and Independent Hospital Pricing Authority (IHPA) and provides an overview of commonly used code sets in health; SNOMED CT-AU features and main use cases; ICD-10-AM features and main use cases; International Classification of Diseases revision; and maps between SNOMED CT and ICD-10. #01#Webinars|#06#All Documents
https://www.youtube.com/watch?v=LgynN5FSFJE&feature=youtu.beIntroduction to AMT webinarAn introductory webinar that provides an overview of the AMT, its structure and coverage, purpose, use cases and more.#01#Webinars|#06#All Documents
https://www.youtube.com/watch?v=QswPMtgVnSo&feature=youtu.beIntroduction to SNOMED CT-AU webinarAn introductory webinar that provides an overview of SNOMED CT-AU, its structure and content, purpose, use cases and more.#01#Webinars|#06#All Documents
https://www.youtube.com/watch?v=QOhAn6KzlRU&feature=youtu.beIntroduction to the FHIR specification webinarThe first of three 1-hour introductory technical webinars. Topics include: an overview of the FHIR specification, the CodeSystem, ValueSet and ConceptMap resources; content negotiation including basic use of HTTP post client; basic SCRUD actions (Search, Create, Read, Update and Delete) and their input/output parameters.#01#Webinars|#06#All Documents
https://www.youtube.com/watch?v=wB-xrol07lU&feature=youtu.beIntroduction to the NCTS products and services webinarThe second of three 1-hour introductory technical webinars. Topics include: NCTS objectives; CodeSystem, ValueSet and ConceptMap resources available; APIs including the National Terminology Server and National Syndication Server; deploying local terminology services using Ontoserver and Snapper; various terminology deployment scenarios and use cases; brief overview of what else we are working on e.g. Medication resource.#01#Webinars|#06#All Documents
https://www.youtube.com/watch?v=c75xdboyPV8&feature=youtu.beLinking AMT and GTIN: Improving Medicines Management and SafetyThis webinar is for pharmaceutical product suppliers and other users of the National Product Catalogue. It provides an overview of the initiative to link AMT CTPP codes with GTINs within the NPC. #01#Webinars|#06#All Documents
https://www.youtube.com/watch?v=rQnzyqTeAnw&ab_channel=AuDigitalHealthLinking AMT and GTIN: Project Requirements for Pharmaceutical Suppliers webinarThis webinar is recommended for suppliers of pharmaceutical products. Topics include a recap of the Linking AMT and GTIN initiative; specific requirements for pharmaceutical suppliers including details of the document pack intended for each supplier, instructions on how to validate the draft AMT-GTIN map and ongoing maintenance processes.#01#Webinars|#06#All Documents
https://www.youtube.com/watch?v=WvhG9qlA5FgShrimp terminology browser – searching SNOMED CT-AU webinarThis webinar demonstrates a popular terminology browser and gives tips and hints on how to search for SNOMED CT-AU content, including the AMT.#01#Webinars|#06#All Documents
https://www.youtube.com/watch?v=Y_hGiuKPFLISnapper:Map – creating maps to SNOMED CT-AU webinarThis webinar demonstrates a tool that enables the creation of maps between SNOMED CT-AU (including the AMT) and other data sources.#01#Webinars|#06#All Documents
https://youtu.be/aZoZoClSg4oSNOMED CT-AU and AMT Subsets webinarThis webinar provides an overview of SNOMED CT-AU and AMT subsets and why they are useful in terminology implementations. Examples of NCTS subsets available in different formats (SNOMED CT reference set, FHIR® ValueSet), the use cases they support, and how to access them will be discussed.
This accompanies the SNOMED CT-AU and AMT subsets presentation.
#01#Webinars|#06#All Documents
https://www.youtube.com/watch?v=KBW3lGwSTPo&feature=youtu.beSNOMED CT-AU hierarchies webinarA webinar that provides an overview of the content available within each of the SNOMED CT-AU hierarchies.#01#Webinars|#06#All Documents
/library/DH_2597_2017_NCTS_BatchRequestSubmissionTemplate_v1.2a.xlsxNCTS Batch Request Submission TemplateA form for the submission of multiple or batches of content requests for both Australian Medicines Terminology (AMT) and SNOMED CT-AU.#02#Business|#06#All Documents
/library/DH_2402_2016_NCTS_RequestSubmissionGuidelinesforTerminologyProducts_v1.1.pdfNCTS Request Submission Guidelines v1.1Provides guidance on how to submit a request to the NCTS for the creation, modification, or inactivation of clinical terminology content.#02#Business|#06#All Documents
/library/DH_2548_2017_Clinical_Terminology_Implementation_Process_and_Checklist_v1.0.pdfSNOMED CT-AU Clinical Terminology Implementation Process and Checklist v1.0This document provides a business level overview of the steps required to implement SNOMED CT-AU and the AMT content within your products or clinical systems.#02#Business|#06#All Documents
/library/DH_2574_2017_SNOMEDCT-AU_Clinical_Scenarios_with_Medicine_Order_v1.0.pdfSNOMED CT-AU Clinical Scenarios with Medicine Order v1.0This document provides example clinical scenarios to show where SNOMED CT-AU and the AMT supports coding of elements within the associated medicine orders in clinical systems.#03#Clinical|#06#All Documents
https://aehrc.github.io/fhir-ts-exemplars/HL7 FHIR Terminology Service ExemplarsA set of UI and client-side exemplar software snippets to illustrate various aspects of interacting with the FHIR Terminology API.#04#Technical|#06#All Documents
/tools/national-terminology-server/NCTS Postman CollectionExample NCTS FHIR operations including requesting an access bearer token, querying the integration API and fetching the syndication feed.#04#Technical|#06#All Documents
/tools/national-terminology-server/NCTS Postman EnvironmentThe default Postman environment variables required to execute the NCTS Postman Collection.#04#Technical|#06#All Documents
http://snomed.org/tig SNOMED CT Technical Implementation Guide (SNOMED International) Detailed specifications of release files and other SNOMED International standards, and guidance on implementation of SNOMED CT. It should be used in conjunction with SNOMED CT-AU Australian Technical Implementation Guide.#04#Technical|#06#All Documents
/library/DH_3243_2020_SNOMED-CT-AU_Australian-Technical-Implementation-Guide_v2.5.pdfSNOMED CT-AU Australian Technical Implementation Guide v2.5Provides practical implementation guidance for software developers and technical consumers on SNOMED CT-AU (including the AMT). It should be used in conjunction with the SNOMED CT Technical Implementation Guide (SNOMED International).#04#Technical|#06#All Documents
https://github.com/AuDigitalHealth/sctau-sample-scriptsSNOMED CT-AU Australian Terminology Sample ScriptsSample SQL scripts to provide a starting point for loading and working with SNOMED CT-AU in a relational database environment (MySQL) and aid in the learning of the release format and data structures#04#Technical|#06#All Documents
/library/NEHTA_1427_2013_SNOMEDCTAU_ReferenceSetImplementationToolkit_v1.0.zipSNOMED CT-AU Reference Set Implementation Toolkit v1.0Sample applications built on Oracle’s Java platform and the Microsoft .NET Framework that demonstrate importing and using SNOMED CT-AU reference sets.#04#Technical|#06#All Documents
/library/DH_3333_2020_NCTS_DocumentLibraryReleaseNote_v2.24.pdf NCTS Document Library Release Note v2.24 Provides a summary of changes for new or updated documentation and resources available in the NCTS document library. #05#Release Notes|#06#All Documents
/library/DH_3319_2020_RCPA_PathologyTerminologyandInformationModels_ReleaseNote_v1.4.pdfRCPA Pathology Terminology and Information Models Release Note v1.4This release note identifies new or changed pathology terminology and information model resources developed by the Royal College of Pathologists Australasia.#05#Release Notes|#06#All Documents
/library/DH_3332_2020_ClinicalTerminology_SNOMEDCT-AU_ReleaseNote_v20201031.pdf SNOMED CT-AU Release Note 31 October 2020 Provides a summary of important content and technical changes to the combined release of SNOMED CT-AU and AMT for the month indicated in the title. #05#Release Notes|#06#All Documents
/library/DH_3303_2020_ClinicalTerminology_SNOMEDCT-AU_ReleaseNote_v20200930.pdfSNOMED CT-AU Release Note 30 September 2020Provides a summary of important content and technical changes to the combined release of SNOMED CT-AU and AMT for the month indicated in the title. #05#Release Notes|#06#All Documents
/library/DH_3280_2020_ClinicalTerminology_SNOMEDCT-AU_ReleaseNote_v20200831.pdfSNOMED CT-AU Release Note 31 August 2020Provides a summary of important content and technical changes to the combined release of SNOMED CT-AU and AMT for the month indicated in the title. #05#Release Notes|#06#All Documents
/library/DH_3237_2020_ClinicalTerminology_SNOMEDCT-AU_ReleaseNote_v20200731.pdf SNOMED CT-AU Release Note 31 July 2020 Provides a summary of important content and technical changes to the combined release of SNOMED CT-AU and AMT for the month indicated in the title. #05#Release Notes|#06#All Documents
/library/DH_3215_2020_ClinicalTerminology_SNOMEDCT-AU_ReleaseNote_v20200630.pdfSNOMED CT-AU Release Note 30 June 2020Provides a summary of important content and technical changes to the combined release of SNOMED CT-AU and AMT for the month indicated in the title.#05#Release Notes|#06#All Documents
/library/DH_3183_2020_ClinicalTerminology_SNOMEDCT-AU_ReleaseNote_v20200531.pdfSNOMED CT-AU Release Note 31 May 2020Provides a summary of important content and technical changes to the combined release of SNOMED CT-AU and AMT for the month indicated in the title.#05#Release Notes|#06#All Documents
/library/DH_2399_2016_SNOMEDCTAU_GuideforTerminologyUseinPrescribing_v1.0.pdfSNOMED CT-AU Guide for Terminology Use in Prescribing v1.0Provides non-technical guidance on how to natively use SNOMED CT-AU (including the AMT) to support medicines ordering and prescribing activities within software systems. Readers should be familiar with the SNOMED CT-AU and AMT concept models and clinical hierarchies as found in the AMT Concept Model and Business Use Cases and SNOMED CT Editorial Guide documents.#02#Business|#03#Clinical|#06#All Documents
/library/DH_2415_2016_AMT_BenefitsAnalysis20142015_v1.1.pdfAMT Benefits Analysis 2014-2015Describes the benefits of recent deployments of AMT as a component of Electronic Medications Management systems at hospitals in Victoria, Tasmania and at Sydney Adventist Hospital.#02#Business|#03#Clinical|#06#All Documents
/library/DH_2542_2017_AMT_Concept_Model_and_Business_Use_Cases_v2.1.pdfAMT Concept Model and Business Use Cases v2.1Describes what the AMT product is, why it exists, which components can be used to achieve certain use cases, and the scope and limitations of AMT as a terminology product.#02#Business|#03#Clinical|#04#Technical|#06#All Documents
/library/DH_3336_2020_AMTv3_EditorialRules_v2.8.pdfAMT Editorial Rules v2.8Detailed information on the naming conventions and rules applied in the creation of all description types for concepts in the AMT. #03#Clinical|#06#All Documents
/library/DH_3247_2020_NCTS-Guide-for-Implementers_v1.1.pdfNCTS Guide for Implementers v1.1This document provides an introduction to the NCTS and guides implementers through common tasks associated with integrating with the NCTS. It provides an explanation of key technical concepts as well as design considerations and deployment scenarios with the use of conformant terminology servers.#02#Business|#04#Technical|#06#All Documents
/library/DH_3244_2020_Introduction_to_the_FHIR_Specification_Presentation_v1.1.pdfIntroduction to the FHIR specification presentation v1.1This presentation accompanies the “Introduction to the FHIR specification webinar”. Topics include: an overview of the FHIR specification, the CodeSystem, ValueSet and ConceptMap resources; content negotiation including basic use of HTTP post client; basic SCRUD actions (Search, Create, Read, Update and Delete) and their input/output parameters.#00#Introductory|#04#Technical|#06#All Documents
/library/DH_3245_2020_Introduction_to_the_NCTS_Products_and_Services_Presentation_v1.2.pdfIntroduction to the NCTS products and services presentationThis presentation accompanies the “Introduction to the NCTS products and services webinar”. Topics include: NCTS objectives; CodeSystem, ValueSet and ConceptMap resources available; APIs including the National Terminology Server and National Syndication Server; deploying local terminology services using Ontoserver and Snapper; various terminology deployment scenarios and use cases; brief overview of what else we are working on e.g. Medication resource.#00#Introductory|#04#Technical|#06#All Documents
/library/DH_3246_2020_Basic_FHIR_Terminology_Services_Presentation_v1.1.pdfBasic FHIR terminology services presentation v1.1This presentation accompanies the “Basic FHIR terminology services webinar”. Topics include: the structure of CodeSystem, ValueSet and ConceptMap resources and basic FHIR SCRUD actions (Search, Create, Read, Update and Delete); specific terminology operations including lookup, subsumes, expand, validate-code, translate and closure; various terminology use cases and applicable operations; tips and hints.#00#Introductory|#04#Technical|#06#All Documents
/library/DH_2757_2018_ClinicalTerminology_GuidanceforPeopleandProcesses_v1.1.pdfNCTS Guidance for People and Processes v1.1Provides guidance to organistions to assist in minimising clinical safety risks and maximise the benefits associated with using SNOMED CT-AU (including the AMT).#02#Business|#03#Clinical|#06#All Documents
/library/DH_2758_2018_ClinicalTerminology_GuidanceforUseinHealthcareSoftware_v1.1.pdfNCTS Guidance for Use in Healthcare Software v1.1Provides guidance for managing risks when implementing SNOMED CT-AU (including the AMT) in healthcare software. This guidance complements the software requirements provided by other eHealth specifications.#02#Business|#04#Technical|#06#All Documents
/library/DH_2759_2018_ClinicalTerminology_GuidanceforUseofMedicalNomenclaturesinInformationExchange_v1.2.pdfNCTS Guidance for Use of Medical Nomenclatures in Information Exchange v1.2Provides guidance to healthcare software developers to assist in managing risk when developing systems that produce and consume clinical messages containing medical nomenclatures.#02#Business|#04#Technical|#06#All Documents
/library/DH_2804_2019_SNOMEDCT-AU_DevelopmentApproachForReferenceSets_v3.3.pdfSNOMED CT-AU Development Approach For Reference Sets v3.3Describes the development approach used in creating SNOMED CT-AU (including the AMT) reference sets developed by the NCTS.#03#Clinical|#04#Technical|#06#All Documents
/library/DH_3334_2020_EP_terminology_requirements_presentation_v1.0.pdfTerminology Requirements for Electronic Prescriptions and Active Ingredient Prescribing presentation v1.0This presentation accompanies the “Terminology Requirements for Electronic Prescriptions and Active Ingredient Prescribing webinar”. Topics include a brief overview of Electronic Prescriptions (EP) and Active Ingredient Prescribing (AIP); terminology requirements; implementation approaches and considerations; and accessing SNOMED CT-AU data. #00#Introductory|#06#All Documents
https://www.youtube.com/watch?v=CBj26LIoQpE&ab_channel=AuDigitalHealthTerminology Requirements for Electronic Prescriptions and Active Ingredient Prescribing webinarThis webinar is recommended for suppliers of prescribing software and dispensing software. It provides information about the terminology requirements that will be mandated in an upcoming version of the electronic prescription conformance profile and active ingredient prescribing guidelines. It also covers common terminology implementation approaches and methods for accessing SNOMED CT-AU (which includes the AMT). #01#Webinars|#06#All Documents
/library/DH_2865_2019_Linking_AMT_and_GTIN_presentation_v1.0.pdfLinking AMT and GTIN: Improving Medicines Management and Safety presentation v1.0This presentation accompanies the “Linking AMT and GTIN: Improving Medicines Management and Safety webinar”. Topics include an overview of the AMT; how the AMT relates to the supply chain; use cases for linking AMT and GTINs; an overview of the initiative; and requirements for pharmaceutical product suppliers.#00#Introductory|#02#Business|#06#All Documents
/library/DH_3335_2020_Linking_AMT_and_GTIN_presentation_v1.1.pdf Linking AMT and GTIN: Project Requirements for Pharmaceutical Suppliers presentation v1.1 This presentation accompanies the “Project Requirements for Pharmaceutical Suppliers webinar”. Topics include a recap of the Linking AMT and GTIN initiative specific requirements for pharmaceutical suppliers including details of the document pack intended for each supplier, instructions on how to validate the draft AMT-GTIN map and ongoing maintenance processes. #00#Introductory|#02#Business|#06#All Documents
/library/NEHTA_1790_2014_SNOMEDCTAU_MappingGuidelines_v2.0.pdfSNOMED CT-AU Mapping Guidelines v2.0Describes a mapping methodology that should be followed when mapping local and proprietary coding systems to SNOMED CT-AU.#03#Clinical|#04#Technical|#06#All Documents
/library/NEHTA_1791_2014_NCTIS_AdverseReactionsReferenceSetImplementationGuide_v1.0.pdfSNOMED CT-AU Adverse Reactions Reference Set Implementation Guide v1.0Comprehensive description of the Adverse Reactions Reference Set group, how it was developed, intended implementation, usage options, and potential considerations for enhancement and expansion.#03#Clinical|#04#Technical|#06#All Documents
/library/NEHTA_1828_2014_AMT_MappingGuidelines_v1.2.pdfAMT Mapping Guidelines v1.2Provides guidelines for mapping local code systems to the AMT for the purpose of an AMT mapping implementation.#03#Clinical|#04#Technical|#06#All Documents
/library/NEHTA_2318_2015_ClinicalTerminology_UsingtheProblemDiagnosisReferenceSetinaSecondaryDataUseScenario_v1.0.pdfThe Problem Diagnosis RefSet in a Secondary Data Use ScenarioFocuses on proof-of-concept techniques developed by the CSIRO to utilise the SNOMED CT-AU problem diagnosis reference set for statistical uses without relying on mapping.#02#Business|#03#Clinical|#04#Technical|#06#All Documents
/learn/specifications/NCTS Specifications v3.0These specifications describe the structure and semantics of terminology content types, the behaviour and interfaces of NCTS conformant server applications and the technical interface contract for the national infrastructure services.#04#Technical|#06#All Documents
/library/DH_2760_2018_ClinicalTerminology_TestCasesforSoftwareandMessaging_v1.1.zip NCTS Test Cases for Software and Messaging v1.1 Test cases for healthcare software systems using SNOMED CT-AU (including the AMT) to confirm if they meet the relevant terminology software requirements as described in the NCTS Guidance for Use of Medical Nomenclatures in Information Exchange and NCTS Guidance for Use in Healthcare Software. #04#Technical|#06#All Documents