Additional FAQ pages are now under development at www.ihtsdo.org/faq.
IHTSDO was established on 23 March 2007 and acquired the SNOMED CT intellectual property on 26 April 2007. IHTSDO is a not-for-profit entity, and it is registered as a Danish Association under Danish Law. The head office is located at the IT University in Copenhagen, Denmark.
The purpose of IHTSDO is to:
IHTSDO's overall vision is to improve the health of humankind by facilitating better health information management. IHTSDO seeks to contribute to improved delivery of care through accurate sharing of health information and the semantic interoperability of health records. We aim to include all clinical and social care professions and to cover both clinical and related health information.
IHTSDO owns and administers the rights to SNOMED CT and we aim to develop, improve, maintain and distribute the terminology (and other terminology products). IHTSDO is promoting, enabling, and supporting the uptake and appropriate use of SNOMED CT in health systems, services, and products around the world.
Support to IHTSDO Members and Licensees is provided as a globally coordinated effort, allowing the pooling of resources to share the costs and benefits.
IHTSDO aims to conduct all activities in accordance with principles of openness, fairness, transparency and accountability to the Members. IHTSDO also seeks cooperation with the World Health Organization and standardization bodies to facilitate harmonization and interoperability of the terminology.
The rights and obligations of Members are fully outlined in the Articles of Association.
In essence Members, through the Association, jointly govern SNOMED CT and have the right to influence its ongoing further development. Their membership fee provides for free use of SNOMED CT within their territory.
Members manage the release, adaptation, distribution and sub-licensing of SNOMED CT and other products of the Association within their Territory (Clause 5 of the Articles). Details of the conditions under which Members may access and modify SNOMED CT are fully outlined in Schedule 3 of the Articles.
One of the key aims in establishing IHTSDO has been to foster international collaboration and contributions to accelerate the further development of SNOMED, and it is anticipated that Members will work together to rapidly improve the quality and comprehensiveness of SNOMED CT.
The Charter Members are those countries that worked together to form the IHTSDO and include Australia, Canada, Denmark, Lithuania, Sweden, the Netherlands, New Zealand, United Kingdom and United States. Collectively they worked together to form the organization.
Representatives from these nine nations led negotiations with the College of American Pathologists (CAP) and put in many hours of work to develop the guiding principles and governance structures for the IHTSDO®. In addition, their financial contributions (or Set-up fees as described in Clause 7.4 of the Articles) provided funds to secure the intellectual property of SNOMED CT and antecedent works.
Charter Members are given special status for the first five years of the Association, in that they have an assured seat on the Management Board. Any vacancies during that time, and all seats after that time, shall be elected on a Regional basis.
The General Assembly is the highest authority of the IHTSDO. It meets at least twice a year, in April and October. All Members have voting rights at the General Assembly and can bring forward items for consideration.
Strategic direction for the IHTSDO will be provided by the Management Board (of twelve) which reports to the General Assembly.
SNOMED CT is considered to be the most comprehensive multilingual health terminology in the world. From abscess to zygote, SNOMED CT includes more than 311,000 unique concepts. The concepts are organized in hierarchies, from the general to the specific. This allows very detailed ("granular") clinical data to be recorded and later accessed or aggregated at a more general level. "Concept descriptions" are the terms or names assigned to a SNOMED CT concept. There are almost 800,000 descriptions in SNOMED CT, including synonyms that can be used to refer to a concept.
In addition, there are approximately 1,360,000 links or semantic relationships between the SNOMED CT concepts. These relationships provide formal definitions and other characteristics of the concept. One type of link is the "IS_A" relationship. This is used to define a concept's position within a hierarchy, e.g. Diabetes Mellitus IS_A disorder of glucose regulation.
SNOMED CT concepts are organized in hierarchies with multiple levels of granularity. The broad coverage of topics included in SNOMED CT is illustrated by range of hierarchies used to organize the standard. Examples include: clinical findings/disorders, procedures/interventions, observable entities, body structures, organisms, substances, and pharmaceutical/biologic products.
Good information is essential for effective health and health care. The safe and appropriate exchange of clinical information is necessary in order to ensure continuity of care for patients across different times, settings, and providers. Today's health information systems include functions to allow for collection of a variety of clinical information, linked to clinical knowledge bases, information retrieval, data aggregation, analyses, exchange, and other functions. SNOMED CT provides a standards-based foundation for these functions. Information systems can use the concepts, hierarchies, and relationships as a common reference point.
The use of SNOMED CT also goes beyond direct patient care. The terminology can, for instance, facilitate functions such as decision support, statistical reporting, outcomes measurement, public health surveillance, health research, and cost analysis.
SNOMED CT provides a standardized, core terminology for electronic health records (EHRs). It contains more than 311,000 active concepts organized into several hierarchies. When implemented in software, SNOMED CT represents clinically relevant information consistently, reliably, and comprehensively as an integral part of the EHR.
A clinical terminology can aid in providing health professionals with more easily accessible and complete information regarding medical history, illnesses, treatments, laboratory results, and similar facts. Standardized information can facilitate improved patient outcomes, clinical decision support, follow-up, and treatment. It can also facilitate analyses based on coded information from IT systems.
SNOMED CT serves as a foundation upon which health care organizations can develop effective analysis applications to conduct outcomes research, evaluate the quality and cost of care, design effective treatment guidelines, and much more.
SNOMED CT is considered to be the most comprehensive multilingual health terminology in the world. It was a joint development of the National Health Service (NHS) in the UK and the College of American Pathologists (CAP). The international clinical terminology was created in 1999 by the convergence of SNOMED RT and the United Kingdom's Clinical Terms Version 3.
Members of IHTSDO may have access to a range of products and services, including:
SNOMED CT has a broad coverage of health-related topics. It can be used to describe a patient's medical history, the details of an orthopedic procedure, the spread of epidemics, and much more. At the same time, the terminology has an unmatched depth, which enables clinicians to record data at the appropriate level of granularity.
The number of concepts in SNOMED CT continues to grow, as illustrated by the graph below. The January 2008 release had 311,000 active concepts, up from 278,000 in 2002.
Specific applications tend to focus on a restricted set of SNOMED CT, such as terms related to ophthalmology. These "Subsets" can be used to present relevant parts of the terminology, depending on the clinical context and local requirements. This means that a drop-down list to select diagnoses in an electronic health record in a mental health facility can be tailored to that setting. Similarly, subsets can be developed to provide appropriate medication pick-lists for nurses in community care.
The opposite is also true. When individual jurisdictions have needs beyond those that can be reflected in a global terminology, perhaps referencing provisions in local legislation, they can develop local or national extensions. Thus, even though SNOMED CT is global in scope, it can be adapted to each country's requirements.
Whether a terminology is comprehensive depends on how you use it. SNOMED CT contains the vast majority of concepts required to record the process of care across the range of clinical professions. The January 2008 release contained over 311,000 active concepts portrayed by almost 800,000 active descriptions and associated to each other by in excess of 1,360,000 defining relationships
These concepts with their inherent unique meanings and formal logic-based definitions are arranged into hierarchies covering the following areas:
IHTSDO works to provide explicit links (cross maps) to health classifications and coding schemes in use around the world, e.g. diagnosis classifications such as ICD-9-CM, ICD-O3, and ICD-10, as well as the OPCS-4 classification of interventions. Additional cross-maps are also under development or consideration, and individual Member countries, Affiliates, and other users have also developed (and in some cases make available) maps to other classifications.
SNOMED CT is a multinational, multilingual terminology. It has a built-in framework to manage different languages and dialects. The International Release includes a set of language-independent concepts and relationships. Today, SNOMED CT is available in US English, UK English, Spanish and Danish. Translations into French, Swedish, Lithuanian, and several other languages are currently taking place. IHTSDO Members are also planning to translate the standard into other languages.
The basic objective of any SNOMED CT translation is to provide accurate representations of SNOMED CT concepts in way that is understandable, usable, and safe. Translations must be concept-based, as term-to-term translations may yield literal expressions that are often meaningless. Instead, the translator analyzes each concept based on the position within the hierarchy, the descriptions, and relationships to other concepts before deciding on the most meaningful translation of a concept. IHTSDO is currently developing guidelines and other supporting documents to support countries undertaking translations.
The cost of developing a new clinical terminology is estimated to be between $US 25 million and $US 55 million. The annual maintenance cost is expected to be in the region of $US 8 million and $US 9 million per year – which is the same as the estimated costs for the IHTSDO to maintain and improve SNOMED CT. These estimates are based on the historic costs borne by the College of American Pathologists and the UK National Health Service.
SNOMED CT is continuously updated to meet the needs of users around the world. Revisions to the international version of SNOMED CT are released twice a year. Each release includes the core of the terminology (concepts, descriptions, and relationships), together with works to support the implementation and use of SNOMED CT, including subsets, cross maps to existing classifications and coding schemes, and an extensive set of guidelines.
These updates are driven by users of the terminology. Examples include refinements to descriptions, re-modeling of concepts, or the addition of new concepts. Prior to release, the SNOMED CT content undergoes a quality assurance process. A preliminary version is then pre-released to members for broader review before the final files are generated and distributed.
Just as our knowledge about health and health care is constantly evolving, so too are terminologies in this domain. As mentioned, the number of concepts in SNOMED CT is growing. A continuous "cleaning up" process also takes place; from 2002 to 2008 approximately 20,000 concepts were deactivated because they were duplicates, outdated, ambiguous, etc. The quality of the descriptions is also improving. For example, more concepts now have sufficient logic definitions – particularly those in the disorders and procedures hierarchies.
You can assist your colleagues around the world in the ongoing development and maintenance of SNOMED CT by becoming a member of IHTSDO's Working Groups and Special Interest Groups; by participating in discussions on the Collaborative Space and at face-to-face meetings; or by submitting requests for specific additions or changes to the standard. We also encourage you to share your experiences of using the standard through the Member Forum, the Affiliate Forum, and at local forums and events organized by IHTSDO's members. For more information, click here.
This flow chart demonstrates how one schedules a telephone conference line and/or a GoToMeeting/GoToWebinar. *When requesting line and/or GoToMeeting/GoToWebinar, please specify name of meeting, date and time required.
This flowchart addresses the following "how do I" questions:
How do I
National members join IHTSDO and have rights and responsibilities that are set out in the Articles of Association (see Schedule 3).
This flowchart demonstrates how to become an affiliate licensee in a low income country and is applicable if one would like access to SNOMED CT. If you are a low income country, please register and apply for SNOMED CT online. More
Please note that there are two additional flow charts, one on how to become an affiliate licensee in Member country and one on how to become an affiliate licensee outside a Member country and a low income country.
This flowchart illustrates how one can nominate a Standing Committee member as of today and a Management Board member (the text in green is specific for this Management Board process). Three triggers are recognized, namely resignation, end of term as per election timetable and vacancy at time of election (*Affiliate Forum eligible to nominate Committee representatives only). More about Committee Nominations
This flowchart demonstrates how one can nominate an IHTSDO Working Group Chair (Project Group and Special Interest Group Chairs). Three triggers are recognized, namely resignation, end of term as per election timetable and establishment of new Working Group. More
This flow chart describes how an Affiliate Licensee can obtain a Namespace Identifier. Please note that there is another flow chart that describes how a Member can obtain a Namespace Identifier. If you are neither an Affiliate Licensee or a Member, please become an Affiliate Licensee. More
This flow chart describes how a Member can obtain a Namespace Identifier. Please note that there is another flow chart that describes how an Affiliate Licensee can obtain a Namespace Identifier. If you are neither an Affiliate Licensee or a Member, please become an Affiliate Licensee. More
Please note that quality management is done throughout this process,
additional feedback loops may thus arise. More
Please note that quality management is done throughout this process, additional feedback loops may thus arise. More
This flow chart describes how a member of the Community of Practice can propose to change the Articles of Association. Please note that there are two separate flow charts on how a General Assembly member and a Management Board member can propose to change the Articles of Association. More
This flow chart describes how a Management Board member can propose to change the Articles of Association. Please note that there are two separate flow charts on how a General Assembly member and a Community of Practice member can change the Articles. More
This flow chart describes how a General Assembly member can propose to change the Articles of Association. Please note that there are two separate flow charts on how a Management Board member and a Community of Practice member can propose to change the Articles. More
The "How do I produce an IHTSDO Technical Report" (April 7, 2011) flow chart provides detail of the different stages for developing an IHTSDO Technical Report, the consultation and approval process as well as how it should be maintained and updated. A more detailed description can be found in the policy document "Development, Approval, Maintenance and Review of IHTSDO Technical reports, Guidelines and Standards" (April 7, 2011).
The "How do I produce an IHTSDO Guideline?" (April 7, 2011) flow chart provides detail of the different stages for developing an IHTSDO Guideline, the consultation and approval process as well as how it should be maintained and updated. A more detailed description can be found in the policy document "Development, Approval, Maintenance and Review of IHTSDO Technical reports, Guidelines and Standards" (April 7, 2011).
The "How do I produce an IHTSDO Standard?" (April 7, 2011) flow chart provides detail of the different stages for developing an IHTSDO Standard, the consultation and approval process as well as how it should be maintained and updated. A more detailed description can be found in the policy document "Development, Approval, Maintenance and Review of IHTSDO Technical reports, Guidelines and Standards" (April 7, 2011).
Membership is open to all countries who are interested in using SNOMED CT and working towards the goals and purpose of the Association. Nations themselves are not members. Members are an organization which is endorsed by the Government to represent that nation. All prospective Members of the IHTSDO must meet certain criteria (refer Clause 4.3.2 of the Articles) in order to join the Association.
The IHTSDO is very keen to encourage new Members, so please contact us to discuss this further.
The process for joining as an Ordinary Member is set out in the IHTSDO Articles of Association. Getting started is as simple as sending a letter from your Ministry of Health indicating your intent to join IHTSDO and the people and the agency/organization/Ministerial Department that would be responsible for SNOMED CT in your jurisdiction. For more information, click here.
To use SNOMED CT, you will need an Affiliate License with the IHTSDO.
If you are based within an existing Member nation, and only wish to use SNOMED CT within that jurisdiction, contact the relevant Member. They will be able to provide further details of how to access the International Release and will also inform you of any additional materials or conditions relevant for use within that Member's territory.
The Affiliate License in member countries is a click-through license, and you'll need to accept the conditions for use prior to accessing SNOMED CT. Most members provide SNOMED CT free of charge to users, although some may leverage a small fee for cost recovery.
If you are based within an existing Member nation, and wish to deploy SNOMED CT in other countries you'll need to check whether those countries are also members of the IHTSDO. The Affiliate license you've received is a world-wide license, so it can be freely used in other IHTSDO Member's territories, but there may be additional extensions or local modifications relevant for use in another nation, so you'll need to check with that Member. There is charge payable to the IHTSDO for use in non-member territories.
If you are based within a country that is not yet an IHTSDO member, please click here for more information about how to obtain an Affiliate License. You can obtain a namespace by emailing info(at)ihtsdo.org
If you are planning to use SNOMED CT for research, click here.
If you are planning to develop your own information systems in-house, click here.
If instead you are intending to procure a system from an external vendor, then all you need to do is stipulate the use of SNOMED CT as one of your requirements when purchasing the system. The Affiliate license which the vendor must hold enables them to provide sublicenses to end users.
IHTSDO and its members encourage the use of SNOMED CT in research that contributes to broadening our collective understanding and knowledgebase.
If you are within a Member nation, please contact your National Release Centre for access to the standard.
If you are in a country that is not yet a member of IHTSDO, you can obtain a license to use the standard through IHTSDO. Qualifying research projects may qualify for a free license if they:
To request a fee waiver, please contact IHTSDO, providing evidence that your research project meets the above criteria.
This was an issue of key discussion within the IHTSDO Board. The key goals of the Board are to ensure that the terminology is
In terms of sustainability, the IHTSDO needs an income stream to be able to maintain and improve the quality of SNOMED CT and ensure that it reflects the latest concepts in clinical practice. There is an expectation that all users of the terminology contribute to this work in accordance with their ability to pay. In addition, maintaining interoperability of the terminology requires changes to the terminology to be constrained, with some level of control over local modifications and enhancements. Both of these factors have the ability to impact patient safety – which requires process to ensure the quality of the terminology and common understanding of encoded data.
Therefore, the Board has opted for a licensing model that provides easy access to the standard at a fair cost, with minimal administrative burden. If alternative approaches that satisfy the three core principles above emerge, they may well be considered and accepted through a vote of the General Assembly.
Yes. IHTSDO's Affiliate Forum is a community of practice concerned with improving the implementation and deployment of SNOMED CT within products and services purchased on a national and/or international scale. It is open to anyone with an Affiliate license. Several National Release Centres also operate forums for SNOMED CT users.
The Affiliate Forum has been created to facilitate communication and collaboration among affiliates and between the IHTSDO and affiliate members on the development and evolution of SNOMED CT and terminology products. The IHTSDO encourages all affiliates to participate in the affiliate forum who will act as an advisory body to the Association and General Assembly. For more information about the Affiliate Forum, please see the Affiliate Forum Overview Page which includes questions and answers including; Who is an Affiliate? How does the Affiliate Forum work? Why do I want to be involved in the Affiliate Forum?
The purpose of a National Release Center (NRC) - or Member Product Management Center (PMCs) - is to provide a central (and single) point within the member's jurisdiction to:
Find more information about National Release Centre here.
The IHTSDO believes in principles of fairness and transparency. To that end, Membership fees are structured on a fair share formula based on your nation's Gross Domestic Product and population (ie. your ability to pay) and the total cost to the Association of maintaining SNOMED CT. The ability to pay relies on the trusted third party, namely the World Bank GNI Atlas.
The spreadsheet on fees will indicate how much your country will pay in a joining fee and annual fee. More detail on fees is contained in the Articles of Association.
SNOMED CT Core will be released twice per year in January and July in English. SNOMED CT Core translations from English will be released 3 months following the Core releases. Over time, the Management Board will evaluate the release profile to ensure member needs are being met in the most productive and efficient manner.
In order to deliver the first of the SNOMED SDO founding principles, to support the care of individual patients by clinical professionals, SNOMED CT needs to interoperate with other standards in the electronic health care environment. Each method of interoperation will have to be defined and conformed to if care delivery is to remain effective and safe.
Effectively therefore, this defined interoperation is in itself a standard. However, this type of standard must be agreed both by the SNOMED SDO and the other standard.
These agreements (or "allied standards") may take the form of a specification, a service or a product. Regardless of format, definition and alteration can typically only be achieved through agreement between the SNOMED SDO and the associated standard.
These collaborations are generally managed by a Harmonization Board. This creates a strong link to the governance processes of the Management Board of the SNOMED SDO, yet leaves sufficient flexibility for the Allied Standard to be managed in a way that best suits its users' particular requirements.
Affiliate Forum members provide a voice from the users of SNOMED CT to the IHTSDO around any issues or concerns relating to licensing, terminology content, modeling, change management, distribution formats and associated policies and procedures.
An Affiliate is a person, partnership, body corporate, association, governmental or local authority or agency, entity holding a current IHTSDO Affiliate License.
See the Affiliate Forum page for instructions on becoming a member of the Affiliate Forum.
Any individual associated with an Affiliate can participate in the Affiliate Forum. In addition, each Affiliate can designate a single person, the Affiliate Voter, to act on its behalf in voting at meetings and on ballots. Participation will be through the Affiliate Forum collaborative site as well as through scheduled meetings and at the IHTSDO bi-annual working group meeting.
Each Affiliate provides contact details for the purpose of receiving notices, and, where the Affiliate has nominated a person as an Affiliate Voter, should specify that person to receive and distribute Affiliate Forum notices of meetings, ballots and other business. Affiliates should also regularly check the Affiliate Forum section on the Collaborative Space, and IHTSDO web-site for recent activity.
Meetings are held in conjunction with the regular twice-yearly IHTSDO meetings at a time considered convenient for attendance by Affiliates.
Each Affiliate is entitled to one and only one vote. If a single Affiliate holds more than one IHTSDO Affiliate license, the Affiliate is still not entitled to more than one vote at a meeting or on a ballot.
Initially, it is proposed that any contributions must either be made by a Member, the IHTSDO, or someone endorsed by a Member or the IHTSDO. For the trial period, it is expected that contributions will with very few exceptions come from Members or the IHTSDO itself. This will keep the scope manageable and provide some quality review prior to resources being contributed. As understanding of the domain increases, the scope of potential contributions could be broadened.
You choose whether you want to contribute to the Member Exchange. There is no obligation under the Articles of Association or the Affiliate License to do so. If you decide to participate, however, contributions will be treated in a defined and consistent way.
The Member Exchange agreement outlines the conditions that apply. In summary, the contributor continues to own the intellectual property in contributions, except for content that becomes part of the SNOMED CT International Release. Participants in the Member Exchange would acquire a broad license to use, modify, and distribute contributed resources.
Contributors are required to warrant that they have the necessary permissions to contribute them under the standard license. Any contributions are made on an "as is" basis, however. Contributors are not asked to warrant that they are fit for a particular purpose.
A variety of different options have been proposed in this regard, including making the resources available to Members only, to Members plus users in Member countries, or to all Affiliate License holders. (Given that many contributed resources will contain substantial portions of SNOMED CT, the latter is a minimum requirement.)
As an organization, we want SNOMED CT to be used as much as possible. To encourage implementation and to provide an incentive for more Members to join the IHTSDO, it is proposed to adopt a relatively open access policy. This would mean that:
As with the Articles of Association, organizations that cease to be Members could continue to use the last version of the resource that they accessed prior to dropping their Membership status. They would not, however, be eligible to access any updates. Obligations to contribute improvements back to the Member Exchange would survive the termination of Membership/Licensure.
With the permission of the contributor, the IHTSDO may also choose to make some resources openly available, including to those who do not hold Affiliate Licenses. This approach might be taken, for example, with educational resources that have been reviewed for quality and that do not include substantial SNOMED CT content.
"Participants" are those using items from the Member Exchange. There is a single multi-party license that will cover their use or any or all products in the Member Exchange to facilitate administration (i.e. if you have access to one resource, you have access to them all). The terms of this license would be analogous to the standard Affiliate License with the following exceptions:
Also, it is expected that the usefulness of modifications contributed back into the Member Exchange will vary. (So probably would the usefulness of original contributions.) This is known and expected. Over time, it may be helpful to introduce a wiki-type mechanism for users of resources to share their experiences with others about what has worked well and what has not.
It is expected that the Member Exchange will represent a significant benefit for current and prospective Members of the IHTSDO, as well as a key strategy to accelerate implementation of SNOMED CT with practical tools and support. We have already had pledges of contributions of resources that cost several million dollars to develop, as well as a number of smaller but potentially equally important resources (e.g. subsets). Some of these contributions are likely to be announced by those who are donating them in the very near future.
Accordingly, IHTSDO has prepared a communications strategy related to the launch of the Member Exchange. The initial announcement of the launch of the trial period is expected in August 2010. A series of follow-up announcements will take place when major contributions are available through the Member Exchange.
No. As per the guiding principles agreed by the Management Board in November 2009, contributors are encouraged but not required to maintain resources that they contribute. The asset register will indicate the last update date and which release of SNOMED CT the resource was based on. Resources with no updates or use (downloads) in a defined period of time (perhaps 5 years?) would be subject to potential removal from the Member Exchange. So would resources with identified quality issues.
It is proposed that IHTSDO make all Member Exchange resources available at no charge to the global community.
Access to the platform on which the Member Exchange is hosted would also be free for IHTSDO Members and IHTSDO. (Once we move to the Collabnet platform for distribution, this would draw on the allocation of IHTSDO Workbench "seats" allocated to each Member. Members who needed more seats could purchase them at the group prices that have been negotiated with CollabNet.)
Affiliates using resources from the Member Exchange in countries that are not yet IHTSDO Members would be required to pay a fee to defray the costs of the platform. To keep administration simple, this fee will be equal to the fee that the user would pay for an Affiliate License. This would mean that there would be no charge in low income countries and for qualifying research and humanitarian projects.
Note: Some Members may lack the capacity to offer a distribution service within their jurisdiction. If this turns out to be the case, IHTSDO could consider providing such a service, possibly on a cost-recovery basis, in the future.
If the Member Exchange is successful, it is possible that more than one user could be developing the same resource (e.g. an extension). For resources that involve SNOMED CT content or that relate to IHTSDO Workbench tools, it is proposed to manage this process through subversion on the IHTSDO Workbench platform in the future. This allows for individual contributions (including potential conflicts and overlaps among them) to be clearly identified. If the group that originally contributed the resource agrees, amendments proposed could be merged into the main path for the resource. It is outside the scope of currently available resources for IHTSDO to manage this process or to broker consensus on the future path for such resources. That said, such projects could be proposed by Members or Working Groups for future IHTSDO Work Plans and considered in the light of other organizational priorities.
In April 2010, the General Assembly agreed to issue resolution as follows:
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