Health+eDecisions+Consensus+Statement

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This wiki page serves as an overview of the consensus positions discussed by the S&I Framework Health eDecisions (HeD) Initiative. Specific areas of analysis were looked at as part of standards harmonization, and a consensus statement has been drafted to guide the discussion on next steps for the Health eDecisions Initiative. The consensus statements represent the views of the Health eDecisions Initiative Workgroup, to-date. **Please review the content, and provide feedback here.**

Standards Harmonization is defined as applying standards to meet the specific requirements of a constrained use case. **The process of harmonization ensures the applicability of various standards for the requirements defined in the HeD Artifact Sharing Use Case 1**, and ultimately the use of applications that generate and integrate the CDS Knowledge Artifact.

There is a subtle difference in the harmonization of a standard versus the development of a standard. The approach adopted for the CDS Knowledge Artifact is to harmonize a number of different standards. This approach is constrained to the CDS Knowledge Artifact and DOES NOT imply that the HeD Initiative is creating new standards to replace existing CDS standards. Harmonization in the context of this initiative is limited to developing a new harmonized standard for use in knowledge artifacts in a CDS environment. This differs from standard development, where a new standard is developed for a much larger purpose that may cover multiple use cases and requirements (an example might be HL7 messaging, IHE XD* profiles, or DICOM).

A real-world analogy would be a lightbulb as the CDS Knowledge Artifact, whereby standards for bulbs exist that are not 100% aligned to the requirements defined in the HeD initiative. The HeD initiative is defining a new harmonized method for developing a lightbulb that will still work in all lamps, but the schema is not constraining that standard in a way that would prevent implementers from changing the energy use of the bulb, the shape of the bulb, or the total brightness of the bulb. This approach ensures a common structure for the CDS Knowledge Artifact, while allowing for a certain degree of flexibility at the system level for implementers.

The reason for placing this definition of standards harmonization in this consensus statement is to make distinct and clear that the schema is focused on reuse to create a new schema for specifically constrained requirements, with the intent to ballot that schema and supporting documentation, including an implementation guide.

The scope of this consensus statement is meant to cover the overall scope of HeD Use Case 1. Consensus is NOT offered in any areas that are outside the scope of HeD Use Case 1 and no analysis of standards outside the scope of Use Case 1 is offered within this consensus statement.

Consensus for the schema(s) that will be used to define the representation of the data elements from the HeD Use Case 1 data elements is also included in scope for this Consensus Statement.

Because the initiative is adopting an accelerated approach for implementation of a CDS solution to pilot and test, the process and pace of standards analysis is significantly quickened from other S&I initiatives, which typically include a more detailed analysis of standards, including formal ratings based on standards criteria. In this accelerated HeD approach, an initial set of standards are laid out for harmonization to be carried over into piloting and testing, with the assumption that changes to this initial set of standards may be needed following testing. Note that there will be continuity across all S&I Framework phases for data elements identified in HeD Use Case 1.

The consensus statement will be updated with additional information as further CDS use cases are developed. Included in the scope for consensus is the approach and standards needed to create a harmonized HeD schema that can be used by CDS and EHR vendors to generate and import knowledge artifacts. Please note that per the definitions established in HeD Use Case 1, “obtain” means to acquire a CDS Knowledge Artifact, while “import” means to incorporate a CDS Knowledge Artifact into a CDS system.

//The summary table below highlights key areas of decision reached by the S&I Framework Health eDecisions workgroup on major issues encountered in standards harmonization. The table of contents shown on the right also allows the reader the opportunity to jump to specific sections of interest:// =Introduction= //The standards harmonization effort for Health eDecisions Use Case 1 (CDS Artifact Sharing) focused on the following key steps in completing its work://
 * **Implementation Area of Analysis** || **Description of this Area** || **General Consensus Statement** ||
 * Performing standards analysis based on the Candidate Standards List, in order to determine the most relevant and appropriate standard(s) for representing the Use Case 1 (CDS Artifact Sharing) requirements and data elements
 * Developing implementation guide(s) for the three CDS artifact types (Event Condition Action (ECA) Rules, Order Sets, and Documentation Templates) and supporting standards
 * Developing a harmonized schema and supporting documentation
 * Providing a final standards recommendation in the form of an Initiative Consensus Statement, and identifying any gaps/enhancements to be communicated to the respective SDOs and/or owners of the specifications. A complete list of candidate standards can be found here

The structure of this Consensus Statement is as follows:
 * Description of the context
 * Summaries of workgroup analysis and decisions to date
 * Use of supporting visuals and guidance (where appropriate)

The consensus statements for review by the workgroup are outlined in **BOLD. These statements will appear in the document and represent preliminary consensus, drawn from the activities of the workgroup, to-date.**

The S&I Framework Consensus Process can be reviewed here.

The Health eDecisions Roadmap, below, outlines the specific milestones and activities to be completed once consensus has been achieved.



Assumptions
A number of assumptions were developed in support of harmonization activities.
 * Standards in the CDS area are relatively immature in implementation
 * Implementation experience is somewhat limited with CDS
 * The CDS knowledge artifacts are transport agnostic

Issues and Challenges
Data models used in developing the schema may or may not map to underlying terminologies and standards, so gaps in both data models and terminologies need to be identified as a necessary part of the HeD initiative. Furthermore, closure of identified gaps will be required in order for the use case to be fully implementable.

Additional issues identified related specifically to policy and technology, and reviewed in the context of the S&I Framework Health eDecisions Use Case 1 (CDS Artifact Sharing), will be listed as they are identified. =Overview of Implementation Approach for Use Case 1= The overview of the HeD initiative approach to implementation of HeD Use Case 1 requirements is shown in the figure below:



Initial Standards Analysis for HeD Specification
The standards analysis phase of the initiative has been conducted by support staff of the S&I Framework in parallel with the development of the Hed Use Case. As part of this activity, initial work included:
 * Reviewing existing CDS implementations from both the proprietary and open source communities, including openCDS
 * Review of relevant roadmaps and reports on CDS (e.g. ACDS reports and recommendations)
 * Reviewing existing organizations and their work in CDS (e.g. CDS Consortium, CDS PI Collaborative, SHARP C Project 2b, etc.)

Because standards associated with HeD Use Case 1 are limited to the representation of a CDS knowledge artifact, the standards reviewed were those that focused on content representation and structure. A list of candidate standards, along with a brief description, can be found. Specific references will be included in the appendix of the implementation guide to be developed by the HeD initiative.

Harmonized HeD Schema Implementation Guide
The implementation guide will define the CDS knowledge artifact schema. The implementation guide will provide information about how to use the schema as well as the mapping/harmonization path back to the original schemas.

The standards analysis conducted to date leads to the proposal of an initial implementation approach centered on the following building blocks:
 * **Specific Actions for CDS Knowledge Artifact** || **Notes on Analysis** ||
 * Transport of the Knowledge Artifact || As per the HeD use case, out of scope.

Assumption is the artifact is transport agnostic. ||
 * Generate the content for the artifact || The artifact will be generated using the Harmonized HeD Schema. ||
 * Collect the knowledge artifact || The artifacts that are collected will use the Harmonized HeD Schema but MAY also exist as a base schema in HL7 vMR, CDSC L3, and/or CREF/ArdenML. ||
 * Import the knowledge artifact || The artifact will be based on the Harmonized HeD Schema, and implementers MAY use the Harmonized HeD Schema Implementation Guide to define how to import the knowledge artifact into their systems.

The artifact will also be mappable to other standards representations which are currently available for use, including the HL7 Order Sets DSTU and the HL7 Arden Syntax. ||

Harmonized HeD Schema
The completed schema MUST address the following 3 CDS interventions: ECA Rules, Order Sets, and Documentation Templates. To meet the goal of defining these interventions, the approach adopted will focus on harmonizing the following schemas currently used for clinical decision support purposes:
 * HL7 Virtual Medical Record (vMR)
 * CDSC L3
 * Allscripts CREF
 * Arden Syntax
 * Yale Guideline Elements Model (GEM)
 * AHRQ eRecs

The harmonized schema would use these standards to represent the structure of the knowledge artifact. In the following figure, the approach for developing the Harmonized HeD Schema is outlined, and further discussion below the figure highlights the key pieces that will go into the schema, and the key decisions made to date:



HL7 vMR
The Harmonized HeD schema will use the existing balloted HL7 vMR Domain Analysis Model (DAM) as a starting point for harmonization. As part of developing the harmonized schema, a list of extensions to the underlying vMR Domain Analysis Model (DAM) will be proposed and documented. The vMR DAM will be the primary model for representing clinical elements.

CDSC L3
As part of promoting greater CDS adoption with a wider community of CDS vendors, the Harmonized HeD schema also maps to the CDSC L3 schema. While this schema is not considered a formally balloted standard through a Standards Development Organization (SDO), it nevertheless contains valuable best practices and implementation experience from the field. L3 will serve as the "container" for the harmonized schema.

CREF and ArdenML
CREF and ArdenML have also been identified as two key schema to map the Harmonized HeD schema to. Although these two standards have not been formally balloted through a SDO, similar to L3, leveraging their widespread use and appeal across the community will help foster continued CDS adoption and implementation. CREF and ArdenML will be applied in the construction of the Harmonized HeD schema as the primary expression language.

Yale GEM
The Yale Guideline Elements Model (GEM) will be incorporated for harmonization. In particular, it will be considered for the design of the metadata model. Specific considerations for the inclusion of GEM include its status as an ANSI standard, extensibility across various tools, and maturity of the standard.

AHRQ eRecs
The AHRQ eRecs specification will be harmonized to facilitate representation of data elements and logical expressions in a structured, codified format, enabling further local processing into CDS rules.

Current consensus around standards to use for the CDS Knowledge Artifact is as follows:
 * L3 schema as the candidate for the container for the knowledge artifact
 * CREF and ArdenML as the candidates for the expression language used within the knowledge artifact
 * HL7 vMR as the candidate standard for the reference model for clinical statements and actions
 * Actions and events are unresolved at this time (the preliminary candidate standard under analysis is Arden Syntax)

Use of Modularity
One of the key areas of consensus for the workgroup is the development of sub-schemas for each module of the HeD schema. Each module will be used together to represent the final knowledge artifact.

GELLO
GELLO is commonly viewed as the query and logical expression language for the CDS knowledge artifact, but with limited implementation experience to date. Further analysis of GELLO will be done as the harmonization process for the CDS Knowledge Artifact progresses. =Position and Strategy for Implementation Guide Policies= In this section, specific policy discussions of the S&I Framework Health eDecisions Workgroup are summarized, with formal recommendations outlined in BOLD. Several policy issues were considered in the process of implementation guide development, including:
 * Exclusion of Transport of the Knowledge Artifact
 * Use of Value Sets and Terminologies
 * Base Mappings and Transformations
 * //Naming Conventions and Styles//
 * //Inheritance//
 * //Conformance//

Exclusion of Transport of the Knowledge Artifact
As noted in the HealtheDecisions Use Case, no specific guidance is provided on transport as part of implementation and the specific assumption is that transport is out of scope. General transport assumptions that are part of implementation include:
 * Metadata associated with the CDS knowledge artifact MAY be transport-dependent. The transport is NOT specifically defined with harmonization of CDS standards.
 * Data types used in the Harmonized HeD Schema will be defined outside the main schema and will be used to define harmonized data types

Use of Value Sets and Terminologies
The Harmonized HeD Schema will use underlying terminologies and value sets already defined within existing standards that are required for Meaningful Use Stage 1 and Stage 2. Given potential gaps in existing terminologies and clinical models, enhancements may be recommended through subsequent analysis conducted by the initiative that falls outside of the scope of the current, initial harmonization effort, in order to ensure alignment within EHR systems. A preliminary list of vocabularies is proposed below; this list will be further expanded on as additional relevant value sets are identified: SNOMED-CT || NDF-RT CVX || CPT ||
 * || Vocabulary ||
 * Allergy* || RxNORM
 * Family History || SNOMED-CT ||
 * Medication || RxNORM
 * Problem || SNOMED-CT ||
 * Procedure || SNOMED-CT
 * Result || LOINC ||
 * Social History || SNOMED-CT ||
 * Vital Signs || LOINC ||
 * Includes foods and environmental allergies, as well as severity

The initial assumption as part of developing the Harmonized HeD schema is that model classes used in developing the schema map to underlying terminologies and standards, and that these mappings can be maintained using ID’s. As part of developing the Harmonized HeD implementation guide, the initiative will further pilot and explore this assumption to ensure this level of alignment.

Base Mappings and Transformations
To be developed with further workgroup discussion – the intent is to provide a base level of mappings back to the underlying schemas used in harmonization, so that existing products can transition to this new CDS schema.

These mappings will include transforms to allow for the underlying schemas to remain intact and to support changes made by users of those schemas, while also allowing these changes to be piloted and tested prior to bringing these changes back to the original owners of the schema.

An example of mappings would be aligning the Harmonized HeD Schema to OpenCDS. OpenCDA uses "Concepts" that have to be managed for all coded elements, which allows rule-writers to refer to broad or narrow categories of disease. Those concepts are then mapped to specific codes using a terminology service. CDSC L3 also takes a similar approach when referencing classes where CDSC has modeled the concepts.

Note that it was decided by HeD participants that inclusion of a patient information model and a provider information model is not in scope for this effort, as this is something that would be addressed by the EHR. =Rationale for Workgroup Decisions= In the interest of producing a working harmonized CDS schema, the belief is that a limited number of initial standards to harmonize will accelerate initial piloting and adoption of a standardized CDS knowledge artifact. It is recognized that pilots will need both a schema with working XML code (and supporting models and documentation) along with a formal implementation guide that explains how to use the schema. As such, the high-level approach proposed in this consensus statement has been drafted by ONC and the S&I Framework as a step forward.

It is assumed that further review of standards will needed once work on the HeD Use Case 2 is finalized, as the scope of standards analyzed to date is limited by the scope of the HeD Use Case 1.