MessageDefinition

Defines the characteristics of a message that can be shared between systems, including the type of event that initiates the message, the content to be transmitted and what response(s), if any, are permitted.

Schema

Elements

Name	Required	Type	Description
url		uri	Business Identifier for a given MessageDefinition Details The business identifier that is used to reference the MessageDefinition and *is* expected to be consistent from server to server. Can be a urn:uuid: or a urn:oid: but real http: addresses are preferred. Multiple instances may share the same URL if they have a distinct version. The determination of when to create a new version of a resource (same url, new version) vs. defining a new artifact is up to the author. Considerations for making this decision are found in [Technical and Business Versions](resource.html#versions). In some cases, the resource can no longer be found at the stated url, but the url itself cannot change. Implementations can use the [meta.source](resource.html#meta) element to indicate where the current master source of the resource can be found.
identifier		Identifier[]	Primary key for the message definition on a given server Details A formal identifier that is used to identify this message definition when it is represented in other formats, or referenced in a specification, model, design or an instance. Typically, this is used for identifiers that can go in an HL7 V3 II (instance identifier) data type, and can then identify this message definition outside of FHIR, where it is not possible to use the logical URI.
version		string	Business version of the message definition Details The identifier that is used to identify this version of the message definition when it is referenced in a specification, model, design or instance. This is an arbitrary value managed by the message definition author and is not expected to be globally unique. For example, it might be a timestamp (e.g. yyyymmdd) if a managed version is not available. There is also no expectation that versions can be placed in a lexicographical sequence. There may be different message definition instances that have the same identifier but different versions. The version can be appended to the url in a reference to allow a reference to a particular business version of the message definition with the format [url]|[version].
name		string	Name for this message definition (computer friendly) Details A natural language name identifying the message definition. This name should be usable as an identifier for the module by machine processing applications such as code generation. The name is not expected to be globally unique. The name should be a simple alphanumeric type name to ensure that it is machine-processing friendly.
title		string	Name for this message definition (human friendly) Details A short, descriptive, user-friendly title for the message definition. This name does not need to be machine-processing friendly and may contain punctuation, white-space, etc.
replaces		canonical[]	Takes the place of Details A MessageDefinition that is superseded by this definition.
status	✓	code	draft | active | retired | unknown Details The status of this message definition. Enables tracking the life-cycle of the content. Allows filtering of message definitions that are appropriate for use versus not.
experimental		boolean	For testing purposes, not real usage Details A Boolean value to indicate that this message definition is authored for testing purposes (or education/evaluation/marketing) and is not intended to be used for genuine usage. Allows filtering of message definitions that are appropriate for use versus not.
date	✓	dateTime	Date last changed Details The date (and optionally time) when the message definition was published. The date must change when the business version changes and it must change if the status code changes. In addition, it should change when the substantive content of the message definition changes. Note that this is not the same as the resource last-modified-date, since the resource may be a secondary representation of the message definition. Additional specific dates may be added as extensions or be found by consulting Provenances associated with past versions of the resource.
publisher		string	Name of the publisher (organization or individual) Details The name of the organization or individual that published the message definition. Usually an organization but may be an individual. The publisher (or steward) of the message definition is the organization or individual primarily responsible for the maintenance and upkeep of the message definition. This is not necessarily the same individual or organization that developed and initially authored the content. The publisher is the primary point of contact for questions or issues with the message definition. This item SHOULD be populated unless the information is available from context.
contact		ContactDetail[]	Contact details for the publisher Details Contact details to assist a user in finding and communicating with the publisher. May be a web site, an email address, a telephone number, etc.
description		markdown	Natural language description of the message definition Details A free text natural language description of the message definition from a consumer's perspective. This description can be used to capture details such as why the message definition was built, comments about misuse, instructions for clinical use and interpretation, literature references, examples from the paper world, etc. It is not a rendering of the message definition as conveyed in the 'text' field of the resource itself. This item SHOULD be populated unless the information is available from context (e.g. the language of the message definition is presumed to be the predominant language in the place the message definition was created).
useContext		UsageContext[]	The context that the content is intended to support Details The content was developed with a focus and intent of supporting the contexts that are listed. These contexts may be general categories (gender, age, ...) or may be references to specific programs (insurance plans, studies, ...) and may be used to assist with indexing and searching for appropriate message definition instances. When multiple useContexts are specified, there is no expectation that all or any of the contexts apply.
jurisdiction		CodeableConcept[]	Intended jurisdiction for message definition (if applicable) Details A legal or geographic region in which the message definition is intended to be used. It may be possible for the message definition to be used in jurisdictions other than those for which it was originally designed or intended.
purpose		markdown	Why this message definition is defined Details Explanation of why this message definition is needed and why it has been designed as it has. This element does not describe the usage of the message definition. Instead, it provides traceability of ''why'' the resource is either needed or ''why'' it is defined as it is. This may be used to point to source materials or specifications that drove the structure of this message definition.
copyright		markdown	Use and/or publishing restrictions Details A copyright statement relating to the message definition and/or its contents. Copyright statements are generally legal restrictions on the use and publishing of the message definition.
base		canonical	Definition this one is based on Details The MessageDefinition that is the basis for the contents of this resource.
parent		canonical[]	Protocol/workflow this is part of Details Identifies a protocol or workflow that this MessageDefinition represents a step in. It should be possible to use MessageDefinition to describe a message to be used by certain steps in a particular protocol as part of a PlanDefinition or ActivityDefinition.
event[x]	✓	Coding, uri	Event code or link to the EventDefinition Details Event code or link to the EventDefinition.
category		code	consequence | currency | notification Details The impact of the content of the message.
focus		MessageDefinitionFocus[]	Resource(s) that are the subject of the event Details Identifies the resource (or resources) that are being addressed by the event. For example, the Encounter for an admit message or two Account records for a merge.
id		string	Unique id for inter-element referencing Details Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces.
extension		Extension[]	Additional content defined by implementations Details May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone.
modifierExtension		Extension[]	Extensions that cannot be ignored even if unrecognized Details May be used to represent additional information that is not part of the basic definition of the element and that modifies the understanding of the element in which it is contained and/or the understanding of the containing element's descendants. Usually modifier elements provide negation or qualification. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. Applications processing a resource are required to check for modifier extensions. Modifier extensions SHALL NOT change the meaning of any elements on Resource or DomainResource (including cannot change the meaning of modifierExtension itself). There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone.
code	✓	code	Type of resource Details The kind of resource that must be the focus for this message. Multiple focuses addressing different resources may occasionally occur. E.g. to link or unlink a resource from a particular account or encounter, etc.
profile		canonical	Profile that must be adhered to by focus Details A profile that reflects constraints for the focal resource (and potentially for related resources). This should be present for most message definitions. However, if the message focus is only a single resource and there is no need to include referenced resources or otherwise enforce the presence of particular elements, it can be omitted.
min	✓	unsignedInt	Minimum number of focuses of this type Details Identifies the minimum number of resources of this type that must be pointed to by a message in order for it to be valid against this MessageDefinition.
max		string	Maximum number of focuses of this type Details Identifies the maximum number of resources of this type that must be pointed to by a message in order for it to be valid against this MessageDefinition.
responseRequired		code	always | on-error | never | on-success Details Declare at a message definition level whether a response is required or only upon error or success, or never. This enables the capability currently available through MSH-16 (Application Level acknowledgement) in HL7 Version 2 to declare at a message instance level whether a response is required or only upon error or success, or never.
allowedResponse		MessageDefinitionAllowedResponse[]	Responses to this message Details Indicates what types of messages may be sent as an application-level response to this message. This indicates an application level response to "close" a transaction implicit in a particular request message. To define a complete workflow scenario, look to the [[PlanDefinition]] resource which allows the definition of complex orchestrations, conditionality, etc.
id		string	Unique id for inter-element referencing Details Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces.
extension		Extension[]	Additional content defined by implementations Details May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone.
modifierExtension		Extension[]	Extensions that cannot be ignored even if unrecognized Details May be used to represent additional information that is not part of the basic definition of the element and that modifies the understanding of the element in which it is contained and/or the understanding of the containing element's descendants. Usually modifier elements provide negation or qualification. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. Applications processing a resource are required to check for modifier extensions. Modifier extensions SHALL NOT change the meaning of any elements on Resource or DomainResource (including cannot change the meaning of modifierExtension itself). There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone.
message	✓	canonical	Reference to allowed message definition response Details A reference to the message definition that must be adhered to by this supported response.
situation		markdown	When should this response be used Details Provides a description of the circumstances in which this response should be used (as opposed to one of the alternative responses).
graph		canonical[]	Canonical reference to a GraphDefinition Details Canonical reference to a GraphDefinition. If a URL is provided, it is the canonical reference to a [GraphDefinition](graphdefinition.html) that it controls what resources are to be added to the bundle when building the document. The GraphDefinition can also specify profiles that apply to the various resources.

Search Parameters

Name	Type	Description	Expression
context	token	A use context assigned to the message definition	MessageDefinition.useContext.value as CodeableConcept
context-quantity	quantity	A quantity- or range-valued use context assigned to the message definition	MessageDefinition.useContext.value as Quantity | MessageDefinition.useContext.value as Range
context-type	token	A type of use context assigned to the message definition	MessageDefinition.useContext.code
date	date	The message definition publication date	MessageDefinition.date
description	string	The description of the message definition	MessageDefinition.description
jurisdiction	token	Intended jurisdiction for the message definition	MessageDefinition.jurisdiction
name	string	Computationally friendly name of the message definition	MessageDefinition.name
publisher	string	Name of the publisher of the message definition	MessageDefinition.publisher
status	token	The current status of the message definition	MessageDefinition.status
title	string	The human-friendly name of the message definition	MessageDefinition.title
url	uri	The uri that identifies the message definition	MessageDefinition.url
version	token	The business version of the message definition	MessageDefinition.version
context-type-quantity	composite	A use context type and quantity- or range-based value assigned to the message definition	MessageDefinition.useContext
context-type-value	composite	A use context type and value assigned to the message definition	MessageDefinition.useContext
identifier	token	External identifier for the message definition	MessageDefinition.identifier
category	token	The behavior associated with the message	MessageDefinition.category
event	token	The event that triggers the message or link to the event definition.	MessageDefinition.event
focus	token	A resource that is a permitted focus of the message	MessageDefinition.focus.code
parent	reference	A resource that is the parent of the definition	MessageDefinition.parent

Inherited Elements

Name	Required	Type	Description
id		string	Logical id of this artifact Details The logical id of the resource, as used in the URL for the resource. Once assigned, this value never changes. The only time that a resource does not have an id is when it is being submitted to the server using a create operation.
meta		Meta	Metadata about the resource Details The metadata about the resource. This is content that is maintained by the infrastructure. Changes to the content might not always be associated with version changes to the resource.
implicitRules		uri	A set of rules under which this content was created Details A reference to a set of rules that were followed when the resource was constructed, and which must be understood when processing the content. Often, this is a reference to an implementation guide that defines the special rules along with other profiles etc. Asserting this rule set restricts the content to be only understood by a limited set of trading partners. This inherently limits the usefulness of the data in the long term. However, the existing health eco-system is highly fractured, and not yet ready to define, collect, and exchange data in a generally computable sense. Wherever possible, implementers and/or specification writers should avoid using this element. Often, when used, the URL is a reference to an implementation guide that defines these special rules as part of it's narrative along with other profiles, value sets, etc.
language		code	Language of the resource content Details The base language in which the resource is written. Language is provided to support indexing and accessibility (typically, services such as text to speech use the language tag). The html language tag in the narrative applies to the narrative. The language tag on the resource may be used to specify the language of other presentations generated from the data in the resource. Not all the content has to be in the base language. The Resource.language should not be assumed to apply to the narrative automatically. If a language is specified, it should it also be specified on the div element in the html (see rules in HTML5 for information about the relationship between xml:lang and the html lang attribute).
text		Narrative	Text summary of the resource, for human interpretation Details A human-readable narrative that contains a summary of the resource and can be used to represent the content of the resource to a human. The narrative need not encode all the structured data, but is required to contain sufficient detail to make it "clinically safe" for a human to just read the narrative. Resource definitions may define what content should be represented in the narrative to ensure clinical safety. Contained resources do not have narrative. Resources that are not contained SHOULD have a narrative. In some cases, a resource may only have text with little or no additional discrete data (as long as all minOccurs=1 elements are satisfied). This may be necessary for data from legacy systems where information is captured as a "text blob" or where text is additionally entered raw or narrated and encoded information is added later.
contained		Resource[]	Contained, inline Resources Details These resources do not have an independent existence apart from the resource that contains them - they cannot be identified independently, and nor can they have their own independent transaction scope. This should never be done when the content can be identified properly, as once identification is lost, it is extremely difficult (and context dependent) to restore it again. Contained resources may have profiles and tags In their meta elements, but SHALL NOT have security labels.
extension		Extension[]	Additional content defined by implementations Details May be used to represent additional information that is not part of the basic definition of the resource. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone.
modifierExtension		Extension[]	Extensions that cannot be ignored Details May be used to represent additional information that is not part of the basic definition of the resource and that modifies the understanding of the element that contains it and/or the understanding of the containing element's descendants. Usually modifier elements provide negation or qualification. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer is allowed to define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. Applications processing a resource are required to check for modifier extensions. Modifier extensions SHALL NOT change the meaning of any elements on Resource or DomainResource (including cannot change the meaning of modifierExtension itself). There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone.

Usage

Implementers should be familiar with the messaging concepts and descriptions found in Messaging using FHIR Resources before working with this resource.

Referenced By

• CapabilityStatement
• MessageHeader