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Making the "Minimum Data Set" Compliant with Health Information Technology Standards

Publication Date
May 17, 2006

U.S. Department of Health and Human Services

Making the "Minimum Data Set" Compliant with Health Information Technology Standards

Executive Summary

John Carter, Jonathan Evans, Mark Tuttle, Tony Weida
Apelon, Inc.

Thomas White
NY State Office of Mental Health

Jennie Harvell and Samuel Shipley
US Department of Health and Human Services

July 5, 2006

This report was prepared under contract between the U.S. Department of Health and Human Services, Office of the Assistant Secretary for Planning and Evaluation, Office of Disability, Aging and Long-Term Care Policy and Apelon, Inc.. For additional information about this subject, you can visit the DALTCP home page at or contact the ASPE Project Officer, Jennie Harvell, at HHS/ASPE/DALTCP, Room 424E, H.H. Humphrey Building, 200 Independence Avenue, S.W., Washington, D.C. 20201. Her e-mail address is:

The opinions and views expressed in this report are those of the authors. They do not necessarily reflect the views of the Department of Health and Human Services, the contractor or any other funding organization.



Health Information Technology (HIT) is helping to improve the quality and continuity of healthcare and reduce unnecessary care costs. The President issued an Executive Order for the “development and nationwide implementation of an interoperable health information technology infrastructure to improve the quality and efficiency of health care.”1 The Secretary of the Department of Health and Human Services (HHS) has identified use of HIT as a critical part of plans to transform our healthcare system, modernize the Medicare and Medicaid programs, and advance medical research. The Secretary has committed that “HHS will do its part by adopting standards and data-sharing processes for Internet-based applications that will help federal programs like Medicaid and Medicare support the use of digital and interoperable health records that are privacy-protected and secure.”2 Private sector leaders convened health information experts and long-term care providers, vendors, and researchers in the first Long-Term Care Health Information Technology Summit. The Summit recommended priority action items to be undertaken by the private and public sectors including adoption of “data, content, and messaging standards that support a unified language and promote interoperability” and specifically recommended that “federally-mandated, standard assessments/data sets…must incorporate HIT content and messaging standards.”3

To support implementation of the Executive Order for an interoperable HIT infrastructure, and the Secretary’s vision of modernized Medicare and Medicaid programs, the Office of the Assistant Secretary for Planning and Evaluation, in collaboration with the Centers for Medicare and Medicaid Services (CMS), sponsored a study to standardize the nursing home Minimum Data Set (MDS). The MDS is one of several patient assessment tools, the use of which is required by the Federal Government as part of reimbursement and regulation. The nursing home MDS, along with other required assessment instruments, is comprised of human-readable question and answer pairs, the responses to which are computer-readable. That is, the MDS is a “form” that can be completed in a way that produces computer-processible data. This data is submitted to regulatory and reimbursement authorities. Linking MDS with HIT content and messaging standards is one step towards interoperability with other care processes. Federal policy makers could implement this linkage as part of larger efforts to modernize the Medicare and Medicaid programs and transform America’s healthcare systems.

This project undertook three major activities. The first activity involved examining standard vocabularies, including those endorsed through the Consolidated Health Informatics (CHI) Initiative,4 and identifying possible content matches between concepts (elements) in these vocabularies and the items (including both questions and answers) in MDS Version 2 (MDSv2) as well as a sample of MDS Version 3 (MDSv3). MDS experts were asked to review and comment on the identified vocabulary matches. The second major activity explored representing MDSv2 using the Logical Observation Identifiers Names and Codes (LOINC) standard. Clinical LOINC is a database in the public domain maintained by the Regenstrief Institute.5 It contains almost 40,000 records, including items from survey and assessment instruments. The third activity was the construction of sample Health Level Seven Version 2 (HL7v2) messages using MDSv2 content that had been linked with standardized vocabularies. HL7v2 is a messaging standard endorsed by CHI that promotes interoperability between computer systems. HL7v2 messages can use LOINC codes and concepts from standard vocabularies, thus combining the project’s activities. These messages permit the electronic exchange of single and multiple standard question-answer pairs, up to and including an entire completed assessment instrument, as well as MDS-derived quality measures.

Results in Brief Standard Content Coverage

We examined the approximately 600 MDSv2 items* (multiple-choice questions and answers) and identified a total of 537 phrases, such as “Acute pain” and “Unpleasant mood in morning” for standard vocabulary matching. These phrases were culled from all sections of the MDS, with some items contributing multiple phrases (e.g., a list of patient diseases from item I1) and others contributing none (e.g., social security number and date of birth from Section AA) when standard terminologies were not applicable. Our automated search and initial expert review of CHI-endorsed terminologies yielded a total of 2,064 standard vocabulary concepts that appeared to match MDSv2 items. After initial expert review, 743 of the 2,064 candidate matches (36%) were classified as “exact” matches of an MDSv2 phrase. These matches covered 250 of 537 phrases (47%). The remaining 1,321 of 2,064 candidate matches (53%) were classified as “related”, meaning that they were judged to be broader, narrower, or overlapping in meaning compared to the MDS phrase. There were no acceptable standard terminology matches found for 43 of the 537 MDS phrases (8%). Over a three-month period, a panel of MDS experts provided 880 written comments on a total of 245 of the 494 (50%) matched MDS phrases. While expert opinion varied on the degree to which the matched standard terms would support successful interoperation, the matches illustrate how a significant portion of the “items” in MDSv2 can be represented using terms from standard vocabularies. Table 1, below, summarizes the standard content coverage findings for the MDSv2. Preliminary matching and review of a sample of MDSv3 phrases suggested that the yield for MDSv3 would be similar to that for MDSv2.

Additional matches and improved precision will be achievable as the vocabulary and standards communities develop rules for combining vocabulary concepts into complex statements (e.g., the activities of HL7’s TermInfo initiative show great promise in achieving this goal).

TABLE 1: Representing a Sample of MDSv2 Using CHI-Recommended Vocabularies
  Exact Match No Match Broader, Narrower, or Partial Match
MDS Question and Answer Phrases
N = 537

Clinical LOINC Representation

In parallel with the terminology matching, this project worked directly with the LOINC Committee to develop an enhanced LOINC format designed to support the computer-based exchange and re-use of interoperable survey instruments, such as the MDS. Since each MDS item is translated verbatim into the LOINC format, it is possible to reconstruct “paper” MDS from the LOINC representation. By unambiguously dividing MDS into “items” -- units -- LOINC provides a useful, near-term way of standardizing MDS. The entire text of the MDSv2 form was encoded in this format.

Construction of HL7 Messages

Together, the standard terminology matching and the MDS representation in Clinical LOINC enable the creation and transmission of useful HL7v2 messages with re-usable content. The HL7v2 standard serves as a “wrapper” for computer-based data sharing. The information “wrapped” includes MDS text segments placed in the LOINC representation and any codes identifying CHI-recommended vocabulary. HL7v2 messaging connects a wide range of computer systems in a variety of healthcare settings.

We demonstrated how three different types of HL7 messages could be constructed using a sample of MDS question and answer pairs that had been linked with codeable vocabularies and placed in an HL7 message format. We used the HL7v2 Observation/ Result (OBX) segment, in particular the OBX-3 and OBX-5 message fields, to represent the assessment results. The HL7 message types that were constructed would support the automatic generation and electronic exchange and re-use of:

  • A single MDS question and answer pair.
  • Multiple MDS question and answer pairs.
  • Algorithmic/computer-generated computation of Quality Measures using existing and future formulas from a set of standard MDS items.

Following a similar process, the entire MDS form could be exchanged using HL7 messaging.


This project has revealed both the potential benefits and the challenges of leveraging HIT standards in the preparation and exchange of complex survey forms such as the MDSv2. On the one hand, most MDS items are easily related to standard vocabulary concepts. On the other hand, experts consulted in this project disagreed on the current ability of these vocabulary standards to provide true interoperation by meaning, such as might be required to auto-populate the MDS from an electronic medical record or to easily compare MDS and MDS results with other surveys and survey results. Important vocabulary challenges identified include:

  • accommodating the complexity and idiosyncrasies of patient assessment instruments;
  • bridging coverage gaps in standard vocabularies; and
  • resolving uncertainty regarding the reproducible combining of standardized vocabulary terms into compound terms intended to match certain MDS items.

Similarly, Clinical LOINC and HL7v2 provide a straightforward and proven path for standardizing question and answer pairs as found in the MDS that will permit the standards-based exchange and re-use of this content. The computing infrastructure required to exploit this path would become available to nursing homes if the government embeds this approach in future modifications of the MDS. HL7v2 messages using questions and answers coded in Clinical LOINC can be stored in publicly accessible repositories, further enabling their re-use. Increased re-use of these items supports the objective of data comparability across settings.

However, if HHS wished to standardize the exchange of the MDS using CHI-endorsed standards, HHS would need to consider modifying the software CMS makes freely available to providers to transmit the MDS using Clinical LOINC and HL7 messaging. Using HL7v2 messages and Clinical LOINC to transmit MDS content would:

  • enable the secure, standards-based transmission of all or parts of the MDS form to payers, regulators, providers, and other entities;
  • promote comparability and re-use of question and answer pairs across instruments;
  • leverage existing software tools and support the development of new software tools, including those that could:
    • identify relationships between data elements, and thus accelerate the re-use of these data elements; and
    • provide clinical decision support.
Concurrently linking MDS content with standard vocabularies, when possible, and using Clinical LOINC and HL7 to support messaging: (a) are actionable means of integrating MDS into a nationwide interoperable health information infrastructure, and (b) provide a near-term method to apply the processes developed during this project to other federally-required patient data collection efforts thus accelerating the realization of associated quality and cost-saving benefits.

Conclusion and Recommendations

The goals of this study were to make the MDS conformant with CHI-endorsed content and messaging standards, and to produce a policy relevant report that describes the issues with integrating these HIT standards into federally-required patient assessment applications. We now summarize our complete findings and recommendations, noting that some are explained more fully in the body of this report.

While this project has shown that CHI-endorsed standard vocabularies such as SNOMED CT, HL7 and ICD-9-CM nominally contain most (up to 97%) of the concepts needed to standardize the intent of MDSv2 and presumably MDSv3, it is equally clear that standardization leading to semantic interoperability will require significant work and an ongoing collaboration between HHS, the developers of patient assessment forms (in this case CMS, the owner of the MDS), and the standards development community. To promote the integration of HIT standards into federally-required patient assessment tools such as the MDS, we advance the following recommendations pertaining to: (i) standardization (using content and messaging standards) of assessment instruments; and (ii) technical and policy infrastructure issues needed to support widespread deployment and re-use of standardized assessment instruments, in conjunction with existing and emerging HIT standards.

Standardization of Assessment Instruments

The Federal Government could apply current and emergent HIT content and messaging standards to federally-required patient assessment tools. The work undertaken in this project on the MDS gives rise to many recommendations that could be considered in the pursuit of this goal. Specifically, the Federal Government could:

  • Create standard, computer-processible versions of patient assessment tools (e.g., the MDS) based on the Clinical LOINC format developed in this project.
  • Create and freely distribute software that supports use of LOINC-formatted, federally-required patient assessment tools (such as the MDS) to enable the electronic transmission of needed patient assessment data in standard form by standard means (i.e., in the case of the MDS such software would be a successor to the Resident Assessment Validation and Entry application.
  • Include in the freely-available software described above, a link to the “usefully related” CHI terminology mappings (e.g., identified through this project) so that the developer of the patient assessment forms (in this case CMS) communicates to the public and private sectors the matching standardized terms that it believes are “usefully related” as such terms are identified.
  • Distribute this linked software (i.e., software supporting LOINC-formatting, linked with related standardized terms) as a “test set” to foster development of standards-based tools and processes within the applicable provider (e.g., nursing home) and software-development communities.
  • Equip developers of assessment/survey forms (e.g. refined versions of the OASIS, IRF-PAI, and other assessments required in the Deficit Reduction Act) with: (i) tools to place needed patient assessment data into a LOINC format; and (ii) convenient (e.g., Web-based) access to standard vocabularies to promote harmonization whenever possible.
  • Support initial testing of such applications to validate, for example, required exchange of:
    • the entire assessment forms and results, as well as
    • multiple question-answer pairs needed to support
      • payment, and
      • quality measure/outcome reporting.
  • Support pilot projects to evaluate and iteratively deploy increasingly standards-enabled assessment applications. For example, the public and private sectors could support the development of initial coding assistant applications that:
    • accept standard terms that describe the patient conditions, demographics, etc.,
    • suggest potential assessment results based on these descriptions,
    • calculate quality/outcome measures based on responses, and/or
    • collect feedback regarding utility of “assistant” functions.
  • Engage the CHI-recommended vocabulary developers to identify and fill gaps in the content and utilization of standard vocabularies.
  • Replicate the process of integrating content and messaging standards for other federally-required assessment tools and government survey instruments.
  • Create and execute a multi-stakeholder governance process, based on continuous improvement principles, for the standards-enabled patient assessment tools, that will:
    • Oversee and align interoperable assessment instrument construction, maintenance and deployment;
    • Collaborate with standards development organizations;
    • Promote public-private partnerships to leverage the cost-reduction and quality-improvement potential of assessment instruments; and
    • Measure and report progress toward assessment instrument compliance with Presidential, HHS and Congressional mandates.

In the near term, we recommend the Federal Government consider deploying a process for integrating HIT content and messaging standards with the emerging MDSv3 and the assessments required in Section 5008 of the Deficit Reduction Act (DRA) as follows:

  • Represent MDSv3/DRA content in LOINC using lessons learned from the LOINC representation of MDSv2; and
  • Re-use the applicable MDSv2 content matches in the emerging MDSv3/DRA content, and conduct additional content matching, including needed subject matter expert review, for the MDSv3/DRA items.

Regarding item re-use across patient assessment instruments (e.g., OASIS and IRF-PAI), and best practices as new health and functional data collection tools are developed, we believe the following activities will facilitate standardization:

  • Consider the development of standard “information models” (e.g., for “pain” scales, used to enhance utility of standard terminologies). Focus, initially, on items that may be re-used in other patient assessment instruments.
  • Search question-answer repositories for any re-usable items.
  • Consider the appropriate distribution of content between the question and answer when specifying needed content, and publish any “lessons learned.”
  • Place needed questions and answers into a LOINC format and submit to Clinical LOINC for coding.
  • Search HIT vocabularies to identify coded content (e.g., a SNOMED-CT concept) that is usefully related to the items being measured and have possible matches reviewed, as needed, by subject matter experts.
  • Work with standard development organizations to address identified gaps in HIT standards.
  • Create a freely and publicly available database that supports the standardized exchange of needed content using HLv2+ messaging, Clinical LOINC, and coded content (when available).

Related Technical and Policy Infrastructure Issues

More generally, given the increasing departmental and government focus on the Federal Health Architecture (FHA), the FHA could examine existing and emerging federal mechanisms to implement and maintain HIT content and messaging standards within the federal healthcare enterprise (e.g., at HHS/National Cancer Institute (NCI), Department of Veterans Affairs (VA), etc.). Such analyses could identify commonalities and differences in these processes and encourage the use of processes that maximally support interoperable health information exchange. For example, an issue identified in this study was the need to maintain links between codeable content and LOINC coded questions and answers to support interoperable exchange and re-use of information. Alternative approaches for maintaining these needed linkages that merit further consideration include the feasibility of using the National Library of Medicine’s (NLM) Unified Medical Language System (UMLS) to maintain and make available links between codeable content and Clinical LOINC. Other FHA partners have also been leaders on several wide-ranging HIT standardization projects has been demonstrated by some FHA partners, including the NCI Center for Bioinformatics in its caBIO, caDSR and caBIG initiatives. The FHA could consider these and other initiatives to identify mechanisms that could be re-used to support implementation of interoperable health information exchange.

This project has also highlighted several additional technical and policy issues that would benefit from review by the FHA partners (e.g., HHS, VA, and Department of Defense). For example the FHA could consider alternative methods of deploying and maintaining HIT standards and identify the methods that could be re-used by Federal Partners to maximize efficient interoperable health information exchange. Issues that the FHA could consider include:

  • How will the FHA evaluate the presence of gaps and redundancies in CHI-approved HIT standards (based on this experience with standardizing the MDS and the experiences of other FHA partners)? Will the recently awarded Health Information Technology Standards Panel (HITSP) contract be used to address these issues across the Federal healthcare enterprise?
  • Should links between federally-required patient assessment content (such as the MDS) and standard content in the NLM UMLS be maintained? If so, what process(es) will be used and who will maintain these links?
  • How do FHA partners combine codeable content (i.e., using post-coordination (combined usage) of multiple standard vocabulary elements)? How are standard development organizations (e.g., the HL7 TermInfo effort) addressing issues related to post-coordination?
  • What mechanisms support re-use of codeable content by and across FHA partners (e.g., how are definitions of codeable content maintained, and made transparent and re-usable)?
  • How do FHA partners exchange and re-use codeable content using standardized messages?
  • How do FHA partners integrate HIT content and messaging standards into various patient assessment and survey instruments?
  • What role(s) could the NLM’s UMLS serve in addressing these and related issues?

In summary, this study has identified:

  • a feasible method to integrate HIT content and messaging standards into federally-required patient assessment tools such as the MDS;
  • steps that the Federal Government could use to integrate HIT content and messaging standards into patient assessment tools; and
  • cross-cutting technical and policy issues that would enhance the infrastructure needed to exchange and re-use information.

Implementation of these recommendations would promote the use of interoperable HIT applications that could improve caregiving and increase administrative efficiencies, (e.g., improving quality monitoring, supporting data re-use, etc.). In addition, this study highlights several issues that the FHA could considered as a part of a larger Continuous Quality Improvement that, if implemented, would efficiently promote data standardization, exchange, and re-use.


  1. "Executive Order -- Incentives for the Use of Health Information Technology and Establishing the Position of the National Health Information Technology Coordinator," April 27, 2004.

  2. "Secretary Leavitt Takes New Steps to Advance Health IT." National Collaboration and RFPs Will Pave the Way for Interoperability. HHS Press Release, June 6, 2005.

  3. LTC HIT Summit: DRAFT Report of Consensus, Action and Strategy. Prepared by Michelle L. Dougherty, RHIA, CHP, American Health Information Management Association.

  4. URL:

  5. URL:


* MDS is organized primarily as a multiple choice questionnaire, and certain questions are only asked in some MDS situations, therefore the exact number of questions actually completed depends on the individual patient circumstances. The MDS form also includes a variety of headings, explanations, examples and other material that lends context to the question being asked. As appropriate, our vocabulary analysis also included these supplements.

The Full Report is also available from the DALTCP website ( or directly at