Welcome to the NLM Value Set Authority Center (VSAC)


For VSAC announcements, please subscribe to the VSAC Updates listserv.


The Value Set Authority Center (VSAC) is provided by the National Library of Medicine (NLM), in collaboration with the Office of the National Coordinator for Health Information Technology and the Centers for Medicare & Medicaid Services.


The VSAC provides downloadable access to all official versions of vocabulary value sets contained in the 2014 Clinical Quality Measures (CQMs). Each value set consists of the numerical values (codes) and human-readable names (terms), drawn from standard vocabularies such as SNOMED CT® , RxNorm, LOINC and ICD-10-CM, which are used to define clinical concepts used in clinical quality measures (e.g., patients with diabetes, clinical visit).


The content of the VSAC will gradually expand to incorporate value sets for other use cases, as well as for new measures and updates to existing measures.


Viewing or downloading value sets requires a free Unified Medical Language System® Metathesaurus License, due to usage restrictions on some of the codes included in the value sets.


The Data Element Catalog contains the complete list of 2014 CQMs and value set names.


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What services does the Value Set Authority Center offer?

The Value Set Authority Center (VSAC) currently serves as the authority and central repository for the official versions of value sets that support Meaningful Use 2014 Clinical Quality Measures (CQMs). The VSAC provides search, retrieval and download capabilities through a Web interface and APIs. The VSAC provides authoring and validation tools for creating new and revising published value sets.


The VSAC will maintain and update the value sets consistent with the overall process for maintaining and updating the 2014 CQMs themselves. Through the VSAC, NLM draws upon its responsibility as the central coordinating body for clinical terminology standards within the Department of Health and Human Services (HHS) to assure the ongoing validity and accuracy of the value sets.

What are Value Sets?

Value sets are lists of specific values (terms and their codes) derived from single or multiple standard vocabularies used to define clinical concepts (e.g. patients with diabetes, clinical visit, reportable diseases) used in clinical quality measures and to support effective health information exchange. Although there are many uses for value sets, a primary purpose of the value sets currently represented in the NLM VSAC is to support the 2014 Clinical Quality Measures prescribed for Meaningful Use of Electronic Health Records. Most of the value sets are therefore used to define the patient populations that should be included in the denominators and in the numerators when computing a clinical quality measure.

How do I download Value Set data from the VSAC?

Once you have a UMLS License, you may log into the Value Set Authority Center (VSAC).


Download Tab: The VSAC provides prepackaged downloadable value set data for every release of the 2014 Clinical Quality Measures value sets.


Search Value Set Tab: Use the filters within the VSAC application to search, view and download specific value sets. You can search by text words, or you can limit your search to specific 2014 Clinical Quality Measures and unique identifiers (OIDs). You can also retrieve all of the value sets associated with subsets of the 2014 Clinical Quality Measures, such as all Eligible Professional (EP) or all Eligible Hospital (EH) measures.


Help Tab (API): The VSAC API offers a REST service to retrieve value sets in XML format, according to the Integrating the Healthcare Enterprise (IHE) Sharing Value Sets (SVS) Technical Framework.

What is the model used for distributing Value Set data from the VSAC?

NLM has implemented the Sharing Value Sets (SVS) Technical Framework (PDF). Alternatively, users may wish to use a Common Terminology Services 2 (CTS2) based service maintained by Mayo Clinic to access NLM VSAC Value Set data.

What are Clinical Quality Measures (CQMs)?

According to the Centers for Medicare and Medicaid Services, "Clinical Quality Measures, or CQMs, are tools that help us measure and track the quality of healthcare services provided by physicians, nurses, hospitals and others in our health care system. These measures use a wide variety of data that are associated with a provider's ability to deliver high-quality care or relate to long term goals for health care quality. CQMs measure many aspects of patient care including: health outcomes, clinical processes, patient safety, efficient use of healthcare resources, care coordination, patient engagements, population and public health, and clinical guidelines."

How can I access official versions of the 2014 Clinical Quality Measures?

Centers for Medicare and Medicaid Services (CMS) provide the official source for clinical quality measures that are required for Eligible Professionals (EP) and Eligible Hospitals (EH) to meet Meaningful Use (MU). CMS is the source of truth for these Clinical Quality Measures.


VSAC offers a Downloadable Resources Table, accessible from the Download tab on the VSAC home page, that provides prepackaged downloads for the most recently updated and released 2014 CQM Value Sets, as well as for previously released versions of these value sets.


Agency for Healthcare Research and Quality (AHRQ) offers the United States Health Information Knowledgebase (USHIK) as an authoritative one-stop shop for public access to Meaningful Use quality measure components. The USHIK provides technical specifications for the 2014 Clinical Quality Measures including their descriptions, computation logic, data elements, context, version comparisons, and value sets. USHIK provides measures and value sets in Excel, PDF and XML.


The Unified Medical Language System® Metathesaurus License, available from NLM, is required for these resources at both VSAC and USHIK.



Narrow search results by selecting from pull-down menus below:


CMS eMeasure (NQF Number)

Quality Data Model Category

Steward

Meaningful Use Measures

Code System

Search the NLM Value Set Repository






Value Set Information Available Updates:   Versions: 

  • Name:

  • OID:

  • Type:

  • Definition ID:

  • Steward:

  • Program:



Value Set Members Expansion ID:



My Value Sets

Search All Value Sets

Downloadable Resources Table


2014 Clinical Quality eMeasures (eCQMs)

Publication Date: April 01, 2014

Available Downloads Sorted by CMS ID Sorted by Value Set Name Sorted by Quality Data Model Category
2014 eCQM Value Sets for Eligible Hospitals (EH)
2014 eCQM Value Sets for Eligible Professionals (EP)
All 2014 eCQM Value Sets (EP and EH)
Catalog and changes between 06/14/2013 and 04/01/2014 eCQM releases

Publication Date: June 14, 2013

Available Downloads Sorted by CMS ID Sorted by Value Set Name Sorted by Quality Data Model Category
2014 eCQM Value Sets for Eligible Hospitals (EH)
2014 eCQM Value Sets for Eligible Professionals (EP)
All 2014 eCQM Value Sets (EP and EH)
Catalog and changes between 04/01/2013 and 06/14/2013 eCQM releases
Retired/Legacy Codes Currently in 2014 eCQM Value Sets

Publication Date: April 01, 2013

Available Downloads Sorted by CMS ID Sorted by Value Set Name Sorted by Quality Data Model Category
2014 eCQM Value Sets for Eligible Hospitals (EH)
2014 eCQM Value Sets for Eligible Professionals (EP)
All 2014 eCQM Value Sets (EP and EH)
Catalog and changes between 12/21/2012 and 04/01/2013 eCQM releases

Publication Date: December 21, 2012

Available Downloads Sorted by CMS ID Sorted by Value Set Name Sorted by Quality Data Model Category
2014 eCQM Value Sets for Eligible Hospitals (EH)
2014 eCQM Value Sets for Eligible Professionals (EP)
All 2014 eCQM Value Sets (EP and EH)
Catalog and changes between 10/25/2012 and 12/21/2012 eCQM releases

CMS ID:

The Excel spread sheet download presents value sets organized in a separate worksheet tab for each CMS Measure ID. The XML download contains a separate XML file for each CMS Measure ID, presented in the Sharing Value Sets (SVS) technical framework.

Value Set Name:

The Excel spread sheet download presents value sets pre-sorted by Value Set Name. The XML download contains one XML file pre-sorted by Value Set Name, presented in the Sharing Value Sets (SVS) technical framework.

Quality Data Model Category:

The Excel spread sheet download presents value sets organized in separate worksheet tabs for each Quality Data Model Category.

VSAC Quick Start Guide


If you require assistance with the VSAC, please contact NLM's customer support.


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Getting Started with VSAC

Access to the Value Set Authority Center for viewing and/or downloading value sets, such as those including CPT® or SNOMED CT® codes, requires a free Unified Medical Language System® Metathesaurus License. Please note it may take 1-5 business days to obtain a license.
After your license has been approved, go to the VSAC application and click 'Sign In' with your UMLS username and password to begin using the VSAC.

Using the VSAC REST API to obtain value sets

The VSAC API offers a REST service to obtain CAS Ticket Granting Tickets (TGT) and Service Tickets. See the JASIG REST API documentation for more details on obtaining Ticket Granting Tickets and Service Tickets.
Broadly, in order to make API calls, do the following:

  1. Obtain a TGT using your UMLS username and password by making a POST request to https://vsac.nlm.nih.gov/vsac/ws/Ticket. The TGT can be re-used to make calls to obtain single-use service tickets and is good for 8 hours.
  2. Use your TGT to make a POST request for a single-use service ticket at the URL https://vsac.nlm.nih.gov/vsac/ws/Ticket/<TicketGrantingTicket>. Specify the URL http://umlsks.nlm.nih.gov as the service in the POST request. Each service ticket is good for 5 minutes but expires after one call.
  3. Use your service tickets to make GET requests as specified in the methods below.

If you already know a Value Set Object Identifier (OID), or a Measure's NQF number or a Measure ID, the API calls are the most straightforward method of retrieving and downloading value set data in XML format.
There are 2 methods available for API calls:


  1. RetrieveValueSet

    RetrieveValueSet takes a Value Set Object Identifier (id) as a parameter. The Value Set Repository returns an expanded value set in XML format. It does not return any metadata (e.g., CQM metadata) associated with a measure.
    Example 1: no version or effectiveDate provided with id parameter. Latest version 20130401 returned.
    https://vsac.nlm.nih.gov/vsac/ws/RetrieveValueSet?id=2.16.840.1.113883.3.666.5.1738&ticket=xxxx
    Example 2: version 20121025 provided with id. Exact version 20121025 returned.
    https://vsac.nlm.nih.gov/vsac/ws/RetrieveValueSet?id=2.16.840.1.113883.3.666.5.1738&version=20121025&ticket=xxxx
    Example 3: effectiveDate 20121231 provided with id. Version 20121025 returned.
    https://vsac.nlm.nih.gov/vsac/ws/RetrieveValueSet?id=2.16.840.1.113883.3.666.5.1738&effectiveDate=20121231&ticket=xxxx

  2. RetrieveMultipleValueSets

    RetrieveMultipleValueSets not only returns an expanded value set, but also returns all metadata associated with the value set(s) such as a CQM or other higher level construct, as well as associated metadata. RetrieveMultipleValueSets can take one the following as parameters:

    • OID

      For use if you already know the object identifier for a value set. The OID parameter returns, in XML format, every expanded value set contained within this OID (including all terms, codes and code systems for each value set) along with the metadata for the each value set.
      Example:
      https://vsac.nlm.nih.gov/vsac/ws/RetrieveMultipleValueSets?id=1.3.6.1.4.1.33895.1.3.0.31&ticket=<ServiceTicket>

    • CMS eMeasure Identifier

      Use this to retrieve all value sets for a given CMS eMeasure ID. The returned XML contains every expanded value set for the eCQM (including all terms, codes and code systems for each value set) along with the metadata for the each value set.
      Example:
      https://vsac.nlm.nih.gov/vsac/ws/RetrieveMultipleValueSets?cmsemeasureid=CMS100v1&ticket=<ServiceTicket>

    • NQF Number

      Use this if you want to retrieve all value sets that support a particular National Quality Forum endorsed clinical quality measure. The returned XML contains every expanded value set contained within this NQFNumber (including all terms, codes and code systems for each value set) along with the metadata for the each value set.
      Example:
      https://vsac.nlm.nih.gov/vsac/ws/RetrieveMultipleValueSets?NQFNumber=0002&ticket=<ServiceTicket>

    • Measure ID

      Use this to retrieve value sets that support a given ID assigned by the Measure Authoring Tool (MAT).
      Example:
      https://vsac.nlm.nih.gov/vsac/ws/RetrieveMultipleValueSets?measureid=146&ticket=<ServiceTicket>

Searching the VSAC with a Web browser

The VSAC Web browser provides a way to query and filter the Value Set Repository. This is useful for an overall view of the value sets and their metadata. The VSAC Web browser application also allows you to download value sets in both XML format and in Excel spreadsheets.
Use the filters and your search terms to narrow your result set.


  1. Query

    All value sets in the VSAC repository are automatically displayed when you first visit the "Search Value Sets"page. You can enter search terms directly into the Query box to narrow the result set. For example, you can type the term 'heart' and click the "Search" button to retrieve all value sets that contain the word 'heart' in a value set name, value set member, or in a term that is algorithmically mapped to the word 'heart.' You can also search by a specific object identifier (OID) that corresponds to one value set or a grouping of value sets.


  2. Filters

    Use the Filters (on the left column of the Web page) to refine your value set retrieval results by CMS eMeasure/NQF Number, Quality Data Model Category, Steward, Meaningful Use Measures, or Code System. Click the "Select" bar under the filter category you need, and select the appropriate check boxes to filter the value sets you are trying to retrieve. Click the Apply Filters button to apply your chosen filters. Click the Clear Filters button to clear all the filters you have selected and re-execute the most recently performed Query box search with no filters.


  3. Search Results and Value Set Details display

    The Search Results initially displays all value sets contained within the VSAC repository. When you enter query terms, or codes, and then apply your desired filters, the Search Results table displays the value sets retrieved by your search. The top right corner of the Search Result table displays the total number of retrieved value sets. Use the check boxes to select individual value sets of interest. Sort the value set list alphanumerically by clicking on any column heading.


  4. Downloading Search Results

    Download: To download value sets in XML format, along with all terms and codes, use the check boxes to select your value sets and click on the Download link above or below the checkbox column in the Search Results - Matched Value Sets table. This download function employs the RetrieveMultipleValueSets API method.


    Export Search Results downloads your search results (your list of retrieved value sets) in Excel format. The downloaded Excel spreadsheet contains two worksheet tabs, one with the information about your query terms and filters (Search Criteria), and the other worksheet tab contains a list of your retrieved value sets (Value Sets). This Excel spreadsheet does not contain any terms or codes for the listed value sets.


    Export Value Set Results downloads in Excel format a single fully expanded value set, including the member codes of the value set. Click on a value set OID to view the value set codes in the Value Set Details tab. Then, click the Export Value Set Results link to download an Excel spreadsheet. The downloaded Excel spreadsheet contains two worksheet tabs, one with the information about your selected value set (Value Set Info), and the other worksheet tab contains a list of the value set's codes (Code List).


Value Set Details View


To display value set details for one specific value set within your Search Results table, click on the OID link for that value set. The Value Set Details view displays the following panels:


  • Value Set Information


    • Available Updates
            
      • Automatic Updates by VSAC: The default Value Set Details view shows the most recent automatic update by VSAC. VSAC periodically inserts new versions of code systems as they become available from their corresponding sources. For example, RxNorm is updated monthly. When VSAC receives a new version of a code system, it generates new expansions of the value sets. VSAC refers to these expansions as 'Automatic updates by VSAC,' which are recalculations of the value set code member list based on the current value set definition.
        Versions: From this secondary pull-down menu, choose your desired automatically updated expansion version, formatted as the date of the update, e.g. 20131030 for October 30, 2013.
      •     
      • Approved by Steward: Value set authors and stewards periodically revise their value sets and approve them for publication by a particular program. For example, the CMS Clinical Quality Measure value sets are updated and reapproved annually.
        Versions: From this secondary pull-down menu, choose your desired steward-approved version, formatted as the date of the update, for example: MU2 EH Update 2013-04-01.

    • Export Value Set Results (Excel): Click this link to download an Excel spreadsheet of the contents of the Expanded Code List for your selected value set.

    • Metadata: Displays information for your selected value set, including the value set Name, OID, Type, Definition ID, Steward, and Program

    • Measure: Displays a table: Clinical Quality Measure (CQMs) Supported by this Value Set. This table contains the following columns:
      CMS eMeasure ID -- Hyperlinked to human readable HQMF file for the measure.
      NQF Number --
      Category - Quality Data Model Category (QDM) assigned by the measure developer during measure development in the CMS Measure Authoring Tool (MAT).
      MU -- CQM Meaningful Use Annual Update release name: CY 2014 EP or FY 2014 EH.

    • Grouping: Displays a table: Grouping Members.
      If your selected value set is a grouping of one or more member value sets, this table lists each member value set and includes the following columns for each member value set: Name, OID and Version.

    • Member Of: Displays a table: Groupings.
      If your selected value set is a member of a grouping value set, this table lists each grouping value set, of which your selected value set is a member, and it includes the following columns for each grouping value set: Name, OID and Version.


  • Value Set Members:


    • Expansion ID: This identifier, in the yyyymmdd format, represents the date that the displayed code list was expanded. The term 'expansion' refers to the process of applying a value set's definition against a version of a code system. Based on the value set's definition, the resulting expanded code list may change as the underlying code system updates its codes.

    • Expanded Code List: Displays a table of the individual Codes, Descriptors, Code System, Code System Version, and Code System OID. Use the text boxes at the top of each column to refine your search. Click on the column headings to sort your results. Click the Export Value Set Results link at the top of the Value Set Details to download this expanded code list in Excel format.


View each row in Search Results

Click within a row to highlight the row. Click the View link at the top or bottom of the Expanded Code List table to view a very brief summary for your highlighted value set.

Register to become an author

When you click on the link below, you will access the general NLM customer service email form.


VSAC users function in two roles: Steward and Author.

Authors create, edit and submit value sets to a designated Steward.

Stewards approve, reject and publish submitted value sets from Authors.

Some authors may be their own Stewards.

If the value sets you create will be stewarded by another organization you must identify the Steward's name and organization name during this VSAC authoring permission request process. If you do not know the stewarding organization that will be providing direct VSAC oversight to your authoring work, please list your own organization as the current stewarding organization you will be associated with. If you don't know of any other users from your organization that will be requesting a Steward role, then indicate you will also be performing the Steward role.


Note: Access to VSAC required a UMLS account.

Don't have a UMLS license/account? Request One Now Forgot Username


Please type the following text for these fields in the email form:


Subject of my comment or question: VSAC Authoring Permissions

My comment or question (required): (Copy and paste the following questions into the comment field of the email form, and provide your answers in the same comment field.)


  1. Your UMLS user name:
  2. Your email address:
  3. Your organization:
  4. Do you require value set authoring permissions? - Yes/No
  5. For what program or activity are you developing value sets?
  6. Please provide a contact person's name, email, and phone # for the program or activity noted in #5:
  7. Will this program or activity contact person be providing direct VSAC oversight to the authoring work you will do in the VSAC?
  8. If you answered YES to #7, please ensure the contact person also requests VSAC authoring access. When your contact applies for VSAC Authoring permissions, they should list you as working with them as an Author, a Steward, or both.
  9. Name the steward organization that will be reviewing your work:
  10. Do you require steward permissions? - Yes/No
  11. For stewards, provide the name and email for the program supervisor, if applicable:
  12. For stewards, provide the organizations and/or names of individuals who will author value sets under your supervision:

Request Author or Steward Permissions

Guidelines for Building Value Sets


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Value Set Authoring - Best Practices

Table of Contents


Overview


The Value Set Authority Center (VSAC) serves as the authority and central repository for the official versions of value sets that support Meaningful Use 2014 Clinical Quality Measures (CQMs) and will soon become a repository of value sets for use in other programs and within the wide range of data models. The VSAC provides search, retrieval and download capabilities through a Web interface and through an API, and it provides updates for the value sets as terminologies change. A major function of the VSAC is to provide authoring tools for users to create value sets.


These guidelines are intended for value set authors. The guidelines provide an overview and specific guidance on the best practices of authoring value sets for clinical quality measures and other healthcare applications. The main focus of these guidelines is to describe criteria that define a good quality value set.


Building High Quality Value Sets


A value set contains specific codes derived from a single code system or vocabulary, for example, RxNorm, ICD-10-CM, ICD-9-CM, SNOMED CT, LOINC, and CPT, although value sets can be grouped to combine code systems. In the CMS Meaningful Use (MU) CQM program value set codes populate an instance of a Quality Data Model (QDM) category of information in an electronic health record. The Health Information Technology Standards Committee (HITSC) Vocabulary Task Force and Clinical Quality Workgroups identified the primary code systems for use with each QDM category of information. The Clinical Quality community continues to work on these recommendations to assure they are more comprehensive and not too restrictive.


Types of Value Sets


Value sets can be built from existing code systems such as SNOMED CT, either by enumerated lists of codes or by logical expressions (e.g., all children of 'breast cancer'). Hence, VSAC supports the following three types of value sets.


Extensional Value Set is a set of concepts, in the form of an enumerated list, selected to serve a specific clinical purpose. A simple enumeration of concepts is not always an ideal approach to represent a data model, as comprehensive approach to measure development dictates examination of complete code hierarchies to define the levels of concept inclusion (see Intensional Value Sets below). An extensional value set should contain codes from only one code system.


Grouping Value Set is a list of several value sets that share a common purpose and similar clinical concepts. A specific example of a grouping value set would be a list of several extensional value sets, each containing codes from a single code system. For MU2 CQMs specifically, value sets included in a grouping must have the same QDM Category, but they do not need to share the same code set. For example, "Hospital Measures-Wound Care" Grouping used in measure CMS188v3 uses three value sets: ICD-9-CM, an ICD-10-PCS, and SNOMED CT extensional value sets, all of which relate to wound care.


Intensional Value Set (for future implementation in VSAC) is a list of codes created from a computed expansion based on a logical statement that often has an algorithmic basis for selection of concepts. It represents a set of concepts that is specified in terms of the intension of use, for example all concepts that are children of a specific node in a tree of concepts. Intensional value sets provide the most comprehensive method of describing the target data model.


Value Set Quality Criteria


Standardization of value sets is becoming imperative, as it can enable comparison across disparate datasets and facilitate reuse of well-defined value sets to advance clinical research studies and interoperability of health informatics analysis systems. Value set authors should clearly understand major principles that define high quality value sets:


Clinical Validity: Value set authors should assure that all included codes correspond to the intent and purpose from a clinical perspective. For example, a code defining breast malignancies might be considered clinically irrelevant in a value set that defines eye disease. However, there might be more subtle nuances in clinical meaning one may need to consider.


Metadata Completeness: Authors must provide correct and complete metadata and add any missing metadata as defined by the data model they use or program under which the authors work. Value sets defined by different clinical data models will have specific sets of metadata. The VSAC Authoring Tool indicates which metadata elements are mandatory. Authors should not populate free-text fields with meaningless information, as this will hinder the collaborative process of eliminating value set redundancy and harmonization efforts of the value set user community.


Non-redundancy: Ideally, a given data element should be presented by one and only one value set for a given code system. Multiple value sets with the same codes should be eliminated to facilitate maintenance and prevent inconsistency over time. For example, duplicate value sets should be avoided, and value sets that share a majority of codes should be considered for merging or revision to assure the value sets are as complete as possible.


All Value Set Codes Are Valid in the Code System: The authors should consider only currently valid codes for inclusion into a value set. This assures proper maintenance of the value sets. In some specific cases the author will need to specify a specific version of the code system and would thus create a static snapshot of the code system. Such cases should generally be an exception of the rule, limited whenever possible, and properly described in the Purpose statements.


Descriptors Match Code System Descriptors: Authors should make sure any descriptors they add manually to value sets match the descriptors in the code system to which the codes belong. The VSAC Authoring Tool provides a descriptor match check as a built in function. The VSAC Authoring Tool performs this validation during batch import of codes into a value set, and during manual insertions of codes and descriptors.


Code List Completeness: A value set should contain all the relevant codes for a particular data element. The coverage of codes should be correct. Authors should make sure the lists are lean and they should scrutinize large value sets. You should devise working rules and quality assessment tests to determine whether or not a concept or code is a proper member of a value set. Authors should describe such rules and tests in the required value set Purpose statement.


Logical Correctness: A value set should contain only the relevant codes for a particular data element and the codes contained in the value set should strictly align with the described Purpose.


Proper Terminological Hierarchies (terminological correctness): Only root codes and their descendants should be present in the value set. Presence of codes rooted at a different concept normally indicates incorrect choice of codes. In complex cases, value set authors should consult terminology experts.


Concept Property Similarity: Value set member concepts should not vary in respect to their properties and attributes, such as semantic type, term type, etc. For example, a value set intended for prescribable drugs should contain only drugs with the property, "Prescribable." This is applicable for concepts that have such properties. The properties should be more similar than dissimilar. For complex cases, value set authors should seek guidance on the matter from terminology experts.


Code System Alignment to Standards: Value set authors should base their value set on the code system recommended by the standards depending on the purpose of their value set and the data model (such as the National Quality Forum Quality Data Model) to which the value set authors may be adhering. Please refer to Table 8: Quality Data Model Categories with ONC HIT Standards Committee Recommended Vocabularies, in the most recent version of the CMS Measures Management System Blueprint, Version 10.0, at
https://www.cms.gov/Medicare/Quality-Initiatives-Patient-Assessment-Instruments/MMS/MeasuresManagementSystemBlueprint.html


Value Set Name


Value Set name is a crucially important metadata element. Value set authors should adhere to specific naming guidelines to assure value sets can be found manually and through automated processing, to encourage reuse of the value sets and to discourage their redundancy. The following guidelines will help you create concise, descriptive value set names that capture the purpose each value set.


Do:
  • Name the value set exactly for what it is, not what you wanted it to be. Avoid including descriptions of the content that was intended but not achieved. Correct the name accordingly if during the course of the work you discovered you were not able to align the value set content with the initial name given to the value set. For example, if you initially named the value set "Oral Anticoagulants" when the intent was to capture only oral anticoagulants for chronic atrial fibrillation, change the name to "Oral Anticoagulants For Chronic Atrial Fibrillation" to align it with the intended purpose.
  • Write the value set name to convey the specific distinguishing characteristics of the member concepts. See the name in the previous bullet for a good example.
  • Use the word "Selected" to indicate that not all concepts consistent with the described name are appropriate. When used, "selected" should be the first word in the name.
  • Use sufficiently descriptive names. The name "Acne" or "Anticoagulants" is not sufficiently descriptive, because it does not describe the scope of the value set.
  • Separate multi-word terms by spaces and not by any other characters, with rare exceptions.
  • Capitalize first letters of all words, as in a title.
  • Make unique value set names. Due to the uniqueness of the value set purpose and content, name redundancy ought to be a very rare occurrence.
  • Limit the value set name to no more than 128 characters.

Don't:
  • Avoid using the following characters: + * ? : - | ! "
  • Avoid abbreviations, unless they are widely accepted in the medical literature.
  • Avoid including the name of the steward responsible for the value set. The steward name is separate metadata captured in the VSAC database.
  • Avoid including the name of the data element to which the value set will be linked.
  • Do not include the name of the Program that sponsors the system the value set is used in, unless it describes a primary distinguishing characteristic of the value set.
  • Do not include the name of the code system used to obtain the concepts, unless it describes a primary distinguishing characteristic of the value set. For example, extensional value sets that belong to a grouping value set might be an appropriate case in which you would include the code system name.
  • Do not include the concept category that characterizes the context of use, unless it describes a primary distinguishing characteristic of the value set requirements. Example: only include the word "Procedure" when the context of the main focus is ambiguous.
  • Avoid using the word "Other" as an alternative to another value set. Each value set name must be understandable independent of any other value set.
  • Do not include "CamelCase" or other composite and delimited words or phrases.
  • Avoid using code descriptors within the value set name.
  • Do not use names of measure types for which the value set is intended. For example, do not include "hospital measure," "patient measure," etc. Include this information in the value set Purpose statements.

Value Set Purpose


The purpose statement is a multi-part free-text mandatory entry. It is designed to provide a clear and comprehensive description of the membership of the value set. This important metadata element must take into account how the members will be used in a clinical measure or in any other intended application. The Purpose statement cannot be validated automatically, so authors should spend time to make this text as informative as possible for human readers to understand the intent of the value set, and how the value set is put together. To avoid redundancy, there should be only one value set for a given purpose. The purpose statement includes four separate fields that the value set author needs to complete:


  1. Clinical Focus - a free text statement describing the general focus of the value set as it relates to the intended semantic space. This can be the information about clinical relevancy, or the statement about the general focus of the value set, such as a description of types of messages, payment options, geographic locations, etc.).

    Example: This set of values contains medications that are commonly used in the outpatient setting for chronic oral anticoagulation by patients with chronic atrial fibrillation. These medications include antithrombotics and anticoagulants that are either specifically mentioned in clinical practice guidelines or are reasonable therapeutic equivalents. The 2012 clinical practice guidelines are dose specific.

  2. Data Element Scope - a free text statement describing how the Data Element in the intended information model defines the concepts to be selected for inclusion in the value set.

    Example: The intent of this data element is to identify patients who are on active medication therapy. Using the Quality Data Model, this particular element would map to the "Medication, Active" element.

  3. Inclusion Criteria - Defines what concepts or codes should be included and why.

    Example: Drugs that have single ingredients should be included. Drug forms that are consistent with oral administration should be included: tablets or capsules. Because the guidelines are dose-specific, only specific drug doses are included. Thus, for a common drug ingredient such as aspirin, the value set contains those aspirin concepts with drug strengths that can reasonably be used to achieve doses between 75 mg and 325 mg.

  4. Exclusion Criteria - Defines what concepts or codes should be excluded and why.

    Example: For medications that have multiple ingredients, drugs that contain additional ingredients that are not specifically used for patients with atrial fibrillation should not be included. The drug concepts should be limited to those which are appropriate for human use and available to be prescribed in the United States. In this specific case, drugs that have the form "powder" should not be included. Drug forms that are not consistent with oral administration should not be included. Drugs that take on injectable, syringe or suppository forms should not be included.

Authors should examine all of their value sets (whether created or inherited) that do not contain Purpose information. Authors need to add Purpose statements by consulting their working notes, re-creating their logic used to build the value sets, and by analyzing the codes in the terminological tools.


Updating Value Sets for the eCQM Annual Update

Code Validation, Expansion Profiles, and Revisions


The following tutorial supports the measure developers and value set developers for the annual updates of the electronic Clinical Quality Measure (eCQM) value sets. The annual update is published each year in April, for the Eligible Hospital (EH) value sets, and in June, for the Eligible Professionals (EP) value sets. This tutorial is useful for other purposes as well, beyond the eCQM value set annual updates.


I.    My Value Sets and Search All Value Sets


eCQM1

My Value Sets contains all value sets, regardless of status, assigned to you as an author and/or as a steward.

Search All Value Sets contains all non-private value sets, regardless of status. Click [Search] to view all.

eCQM2

Use the filter boxes to refine your results, and click on any column heading to sort your results.

eCQM3

II.    VSAC Authoring Permissions

  • In addition to UMLS License credentials, you must also obtain VSAC authoring/stewarding permissions by contacting the VSAC staff at http://apps2.nlm.nih.gov/mainweb/siebel/nlm/index.cfm .
  • A value set must be assigned to an author and steward group in order for an author or steward to have access to the value set for the purpose of editing and updating and publishing.
  • New value sets created by authors in the VSAC are automatically associated to the author who created it.
  • If you authored draft value sets in the Measure Authoring Tool prior to the MAT-VSAC import on 11/24/2013 then you must contact the VSAC staff directly to associate your draft value sets to your author and steward group.
  • If you need to update your authored value sets that you previously published in an eCQM Annual Update, you must contact the VSAC staff directly to associate your published value sets to your author and steward group.

III.    What is an Expansion Profile?

First, expansion refers to the calculation of value set's list of codes according to a defined rule or set of rules. An example of a rule could be applying the value set's list of codes to a particular code system version.


Second, an expansion profile is a set of rules defined by a particular program, such as the CMS Clinical Quality Measures Value Sets Annual Update. For example, the eCQM 2014 Annual Update expansion profile applies a set of allowable code system versions, defined by CMS, as well as a set of desired legacy codes, approved by CMS.


The Expansion Profile for the eCQM 2014 Annual Update will validate value set code lists against the code system versions defined by CMS and ONC.


IV.    Validate a Previously Published Value Set against an Expansion Profile

Value sets that were previously published, some were last published over one year ago, have likely undergone some changes due to periodic updates to the code systems on which the value sets were based. Some codes may now be invalid or inactive (retired), and some codes may have remapping information to other codes if the code system provided this information.


Authors need to review all value sets they wish to publish for the upcoming eCQM Annual Updates.


  1. Find your value sets in My Value Sets, if they have been assigned to you. If a value set is not yet assigned to your Author Group, please contact NLM VSAC staff as soon as possible.
  2. Click on the value set OID to review your value set.
  3. In the Value Set Code List, click the Validate link to apply the appropriate Expansion Profile (MU2 EH Update 2014-04-01) to your value set codes.
    In the Code Validation pop-up box, click [Expand] to view the expansion results.
    eCQM4

  4. You can click the [View] button to see exactly which code system versions are being applied to your value set codes.
    eCQM5

  5. Review the Expansion table looking for codes marked Invalid or Inactive. These invalid and inactive codes should be removed from your value set unless there is a Remapped code available for the inactive/invalid code. There will be very few cases of Remapped codes at this time.
    eCQM6


V.    View Remap Info (currently for RxNorm value sets only)

  1. Use the column headings to sort your view of validation and remapping information to facilitate reviewing the validation table.
  2. If Remapping codes exist for any of your inactive/invalid codes, you will see a [View Remap Info] button at the top right of the table. When you click on this [View Remap Info], you will see a new window providing a table with remapping information. You should review the remapped codes.
    eCQM7


VI.    Invalid or Inactive?

The terms invalid and inactive are confusingly similar because they both mean the code should be removed from the value set, but for different reasons.
Invalid: The code never existed in the code system, it could be a typo, or it has been retired from the code system. You should remove invalid codes from your value sets.
Inactive: The code system has decided to suppress this code for reasons particular to the code system. You should remove inactive codes from your value sets.


VII.    Making Changes to Your Value Set

  1. Before you modify your code list, it is important to first change the code system version to the appropriate code system version for your program release, as defined by your agency. For example, the appropriate code system version for RxNorm will be 2014-01 for both the EH and EP annual updates in 2014.

    You will need to manually remove old (inactive/invalid) codes from your value set and add the remapped codes to your value set. Currently this is a manual process.

  2. To make changes to your value set,
        a. If your value set is in Draft status and was not previously published, click the [Edit] button at the bottom of the Value Set Code List table.
    eCQM8

        b. If your value set is in Published status, and was previously published, click the [New Version] button at the bottom of the Value Set Code List table.
    eCQM9

  3. Check the checkboxes beside codes you wish to remove from your value set, and then click the trashcan icon at the top of the Value Set Code List table.
    eCQM10

  4. To add individual codes to your value set, click the plus (+) icon at the top of the Value Set Code List table. This creates a new empty row at the top of the Value Set Code List table. Paste in the code field the code you wish to add, for example, a code that was mapped to an inactive or invalid code.
    eCQM11

    eCQM12


VIII.    Importing Codes into Your Value Set

In many cases, you may have a long list of codes that you wish to add to your value set and then Validate. You may have this list of codes stored in a local spreadsheet. You can copy the column of codes from your spreadsheet and add them to your value set by using the Import link at the top of the Value Set Code List table.

  1. If your codes are in an Excel spreadsheet, select the spreadsheet column that contains the codes (except for the column heading of course). Copy the selected column of codes to your local clipboard.
    eCQM13

  2. In the VSAC Authoring Tool, in a value set you are modifying, confirm you are in [Edit] mode by clicking the [Edit] or [New Version] button at the bottom of the Value Set Code List table. If you do not see the [Edit] or [New Version] button, you may not be the Value Set Author for this value set, or the value set may need to be withdrawn from a more advanced state (Proposed, Approved, Ready to Publish).
    Before importing your list of codes, you need to select a Code System and Code System Version for your value set. Your spreadsheet codes you are about to import will be validated against your selected Code System and Code System Version.
  3. In the Value Set Code List table to which you wish to add this list of codes, click the Import link at the top of the Value Set Code List table.
    eCQM14

  4. In the Import Codes dialog pop-up box, simply paste your codes and then click the [Import] button.
    eCQM15

  5. If any of your codes are invalid, the import tool will not allow them to be imported.
  6. Alternatively, if you have your codes in a non-spreadsheet format, you can also copy/paste these codes into the Import Codes tool. You will need to select the appropriate text separator in this case: space, semicolon, tab, or pipe.

Author and Steward Roles

Roles represent a set of allowed functions that VSAC users request from VSAC Administrators. VSAC Administrators arrange VSAC users into Steward groups and Author groups. A group can contain one or more members and users can belong to more than one group, of either type. VSAC Administrators create these groups based on the requests of Stewards. Currently, VSAC has the following two role types:


Authors have permissions to create, edit and delete their own draft value sets, as well as to submit value sets to their assigned Stewards for approval, and withdraw value sets from approval. New VSAC Authors need to request these Authoring permissions from VSAC Administrators for assignment to Author group(s), based on working relationships with stewarding organizations. Please click the Author Registration link at the top of the VSAC Web page for the instructions on how to request such permissions from VSAC Administrators.


Stewards have permissions to approve, reject, and publish value sets that their assigned Author groups create and submit. Stewards provide overall coordination and management of the value sets created by Authors under a specific program or for a specific purpose. Stewards should adhere to the goals of their stewarding organization with regard to the content and maintenance of the value set.



Functions

Authors may create, and edit value sets, and they may submit value set for review by a Steward group. Authors may also withdraw a value set from the Steward approval process if the author feels more work needs to be completed prior to approval. When creating a value set, the user will need to pick the appropriate Author group as well as the appropriate Steward group for the new value set. Any user within an Author group can make changes to all value sets within that Author group. When an Author submits a value set for Steward approval the value set status changes to Proposed.


Stewards are responsible for approving, rejecting, publishing and maintaining value set content. A Steward can select to "approve" a Proposed value set which will change the status to Approved. A Steward can "reject" the Proposed value set which will change the status back to Draft, making the value set available for editing by the Author group members. After the Steward approves the value set, the Steward can "publish" the value set by selecting the [Publish] button and selecting a publication date for the value set. Once the Steward selects the publication date for the value set, the value set status changes to Ready to Publish, and the VSAC system will automatically publish the value set on the date set by the Steward, changing the value set status to Published.


Authors and Stewards need to communicate outside the VSAC environment to support their workflow.


Example

At the request of users, VSAC Administrators create a group called "AMA MU3 Steward," consisting of the VSAC users who act as Stewards for the value sets created in support of AMA MU3 measures. Based on a user list provided to VSAC by the primary Steward contact for the AMA work, VSAC administrators place a set of users into an Author group, named "AMA MU3 Author." These Authors may then work on the value sets associated with the AMA MU3 Author group. Author groups can also be used to place users into logical working units for the needs of their particular program. When this need arises, the lead Steward can request that VSAC Administrators create another Authoring group, for example, "Author Contractor X." When an Author creates a new value set, she needs to select the correct Steward group responsible for the newly created value set. The AMA MU3 Steward group will be the only users, in this example, that can move value sets submitted by AMA MU3 Author group from Proposed to Approved status and then to Ready to Publish status. An AMA MU3 Steward may also decide that a Proposed value set needs further work and may Reject the value set which will change the value set status back to Draft - also communicating to one or more of the users in the AMA MU3 Author group that the value set needs changes. This Steward communication to the Authors must occur outside the VSAC.

Authoring Workflow - State Diagram

Authoring-Workflow-State-Diagram

VSAC Auto-Update Policy

The Value Set Authority Center (VSAC) is considered the source of truth for high-quality value sets for use across various programs, such as Meaningful Use. These value sets use terminology standards such as RxNorm, SNOMED CT, and LOINC that are updated on a regular basis. When new versions of these terminology standards are published, VSAC consumes them and attempts to create new membership lists (expansions) of the value sets using these terminologies based on the latest rules (definitions) that an author/steward used to define the value set. Providing the latest expansions of value sets will become increasingly important as more and more value sets in VSAC are defined intensionally, which is discussed in more detail below.


Value Set Definition


When creating value set content, authors are defining the rules of the value set membership. VSAC refers to this as the value set definition. For extensional value sets, the definition identifies codes or concepts from a given terminology (code system). For intensional value sets, the definition is expressed as a logical rule, e.g., "All human prescribable RxNorm semantic clinical drugs that have the active ingredient warfarin." VSAC would then compute this rule against a specified version of the code system to create the expansion list.


Value Set Expansion


VSAC refers to the list of codes or concepts that belong to a value set as the Expanded Code List of the value set, or simply expansion. The term 'expansion' refers to the process of applying a value set's definition against a version of a code system. Based on the value set's definition, the resulting expanded code list may change as the underlying code system updates its codes. In the RxNorm example above, a drug company could develop a new drug containing warfarin, possibly resulting in the addition of a new code in RxNorm. Conversely, an existing drug could go off the market, and its corresponding code will become inactive in the next version of RxNorm, and thus excluded from the value set in the subsequent automatic update by VSAC. Codes that become inactive due to a code system update may map to another code or several codes. Sometimes inactivated codes may have no corresponding remapped codes. Such events lead to code membership change in the value set, and in turn may precipitate quantitatively and qualitatively new value set expansions. For grouping value sets, expansion reflects changes in component extensional or intensional value sets due to code membership (code expansion) or definition updates.


Value Set Update Process


VSAC consumes new versions of code systems as they become available through their corresponding sources. For example, RxNorm is inserted monthly. When VSAC receives the new version of the code system, it generates new expansions of the value sets. We refer to these expansions as 'Automatic updates by VSAC', and these are essentially recalculations of the value set code membership list based on the current definition.


Automatic VSAC expansions may significantly differ from the expansions intended for consumption by a specific program or measure, for example by the Meaningful Use program. Therefore, such updates are intended mainly as a snapshot of the dynamic code member changes in a value set and are not endorsed by respective value set stewards for use within a certain program. Depending on the rules that govern a given program, authors and stewards should periodically update their value sets to bring them in line with changes that may have occurred in the underlying terminologies. As a result of this revision process, authors and stewards create new versions of value sets they approve for specific program use.


In the VSAC Authoring Tool, when authors want to update a value set, they create a new version of the value set. This new version retains the value set OID, but assumes Draft status. While the value set is in Draft status, authors should regularly check if a new version of the code system becomes available through the provided VSAC Authoring Tool interface. Authors should select the most recent available code system version to re-expand the value set code list to capture the most recent values in the terminology. VSAC creates a Definition ID and an Expansion ID for new versions of value sets only after stewards approve and publish new version of value sets.


Display of Value Set Versions


In the VSAC search interface, authors can view value sets expansions that have been auto-generated by VSAC, as well as those that have been steward-approved for use by a program. Those are identified by corresponding selections in the 'Available Updates' pull-down menu as 'Approved by Steward' and 'Automatic updates by VSAC' (see snapshots below).


The selections in the secondary 'Versions' pull-down menu include official program-published value set versions by the program's official release, or other versions the steward may have approved for a specific program or use.


Approved by Steward Version Policy

Automatic updates by VSAC display as expansion version identifiers formatted as the date of the update, e.g. 20131030 for October 30, 2013 (see the snapshot below). The default Value Set Details view shows the most recent automatic update by VSAC.


Automatic updates by VSAC Version Policy

External Links