Evidence

The Evidence resource describes the conditional state (population and any exposures being compared within the population) and outcome (if specified) that the knowledge (evidence, assertion, recommendation) is about.

Schema

Elements

Name	Required	Type	Description
url		uri	Canonical identifier for this evidence, represented as a URI (globally unique) Details An absolute URI that is used to identify this evidence when it is referenced in a specification, model, design or an instance; also called its canonical identifier. This SHOULD be globally unique and SHOULD be a literal address at which at which an authoritative instance of this evidence is (or will be) published. This URL can be the target of a canonical reference. It SHALL remain the same when the evidence is stored on different servers. 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[]	Additional identifier for the evidence Details A formal identifier that is used to identify this evidence 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 evidence outside of FHIR, where it is not possible to use the logical URI.
version		string	Business version of the evidence Details The identifier that is used to identify this version of the evidence when it is referenced in a specification, model, design or instance. This is an arbitrary value managed by the evidence 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. To provide a version consistent with the Decision Support Service specification, use the format Major.Minor.Revision (e.g. 1.0.0). For more information on versioning knowledge assets, refer to the Decision Support Service specification. Note that a version is required for non-experimental active artifacts. There may be different evidence 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 evidence with the format [url]|[version].
name		string	Name for this evidence (computer friendly) Details A natural language name identifying the evidence. 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 evidence (human friendly) Details A short, descriptive, user-friendly title for the evidence. This name does not need to be machine-processing friendly and may contain punctuation, white-space, etc.
shortTitle		string	Title for use in informal contexts Details The short title provides an alternate title for use in informal descriptive contexts where the full, formal title is not necessary.
subtitle		string	Subordinate title of the Evidence Details An explanatory or alternate title for the Evidence giving additional information about its content.
status	✓	code	draft | active | retired | unknown Details The status of this evidence. Enables tracking the life-cycle of the content. Allows filtering of evidences that are appropriate for use versus not.
date		dateTime	Date last changed Details The date (and optionally time) when the evidence 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 evidence changes. Note that this is not the same as the resource last-modified-date, since the resource may be a secondary representation of the evidence. 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 evidence. Usually an organization but may be an individual. The publisher (or steward) of the evidence is the organization or individual primarily responsible for the maintenance and upkeep of the evidence. 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 evidence. 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 evidence Details A free text natural language description of the evidence from a consumer's perspective. This description can be used to capture details such as why the evidence 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 evidence 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 evidence is presumed to be the predominant language in the place the evidence was created).
note		Annotation[]	Used for footnotes or explanatory notes Details A human-readable string to clarify or explain concepts about the resource.
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 evidence instances. When multiple useContexts are specified, there is no expectation that all or any of the contexts apply.
jurisdiction		CodeableConcept[]	Intended jurisdiction for evidence (if applicable) Details A legal or geographic region in which the evidence is intended to be used. It may be possible for the evidence to be used in jurisdictions other than those for which it was originally designed or intended.
copyright		markdown	Use and/or publishing restrictions Details A copyright statement relating to the evidence and/or its contents. Copyright statements are generally legal restrictions on the use and publishing of the evidence.
approvalDate		date	When the evidence was approved by publisher Details The date on which the resource content was approved by the publisher. Approval happens once when the content is officially approved for usage. The 'date' element may be more recent than the approval date because of minor changes or editorial corrections.
lastReviewDate		date	When the evidence was last reviewed Details The date on which the resource content was last reviewed. Review happens periodically after approval but does not change the original approval date. If specified, this date follows the original approval date.
effectivePeriod		Period	When the evidence is expected to be used Details The period during which the evidence content was or is planned to be in active use. The effective period for a evidence determines when the content is applicable for usage and is independent of publication and review dates. For example, a measure intended to be used for the year 2016 might be published in 2015.
topic		CodeableConcept[]	The category of the Evidence, such as Education, Treatment, Assessment, etc. Details Descriptive topics related to the content of the Evidence. Topics provide a high-level categorization grouping types of Evidences that can be useful for filtering and searching.
author		ContactDetail[]	Who authored the content Details An individiual or organization primarily involved in the creation and maintenance of the content.
editor		ContactDetail[]	Who edited the content Details An individual or organization primarily responsible for internal coherence of the content.
reviewer		ContactDetail[]	Who reviewed the content Details An individual or organization primarily responsible for review of some aspect of the content.
endorser		ContactDetail[]	Who endorsed the content Details An individual or organization responsible for officially endorsing the content for use in some setting.
relatedArtifact		RelatedArtifact[]	Additional documentation, citations, etc. Details Related artifacts such as additional documentation, justification, or bibliographic references. Each related artifact is either an attachment, or a reference to another resource, but not both.
exposureBackground	✓	Reference<EvidenceVariable>	What population? Details A reference to a EvidenceVariable resource that defines the population for the research.
exposureVariant		Reference<EvidenceVariable>[]	What exposure? Details A reference to a EvidenceVariable resource that defines the exposure for the research.
outcome		Reference<EvidenceVariable>[]	What outcome? Details A reference to a EvidenceVariable resomece that defines the outcome for the research.

Search Parameters

Name	Type	Description	Expression
composed-of	reference	What resource is being referenced	Evidence.relatedArtifact.where(type = 'composed-of').resource
context	token	A use context assigned to the evidence	Evidence.useContext.value as CodeableConcept
context-quantity	quantity	A quantity- or range-valued use context assigned to the evidence	Evidence.useContext.value as Quantity | Evidence.useContext.value as Range
context-type	token	A type of use context assigned to the evidence	Evidence.useContext.code
date	date	The evidence publication date	Evidence.date
depends-on	reference	What resource is being referenced	Evidence.relatedArtifact.where(type = 'depends-on').resource
derived-from	reference	What resource is being referenced	Evidence.relatedArtifact.where(type = 'derived-from').resource
description	string	The description of the evidence	Evidence.description
effective	date	The time during which the evidence is intended to be in use	Evidence.effectivePeriod
identifier	token	External identifier for the evidence	Evidence.identifier
jurisdiction	token	Intended jurisdiction for the evidence	Evidence.jurisdiction
name	string	Computationally friendly name of the evidence	Evidence.name
predecessor	reference	What resource is being referenced	Evidence.relatedArtifact.where(type = 'predecessor').resource
publisher	string	Name of the publisher of the evidence	Evidence.publisher
status	token	The current status of the evidence	Evidence.status
successor	reference	What resource is being referenced	Evidence.relatedArtifact.where(type = 'successor').resource
title	string	The human-friendly name of the evidence	Evidence.title
topic	token	Topics associated with the Evidence	Evidence.topic
url	uri	The uri that identifies the evidence	Evidence.url
version	token	The business version of the evidence	Evidence.version
context-type-quantity	composite	A use context type and quantity- or range-based value assigned to the evidence	Evidence.useContext
context-type-value	composite	A use context type and value assigned to the evidence	Evidence.useContext

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

The scope of the Evidence resource is to describe the conditional state (population and exposures being considered or compared within a population) with or without the outcomes that knowledge (evidence, assertion, recommendation) is about. The Evidence resource is a commonly bundled series of evidence variables from the "PICO" specification of medical knowledge: Population - the population within which exposures and outcomes are being considered Intervention - the conditional state or exposure state being described for which one is expressing the risk of or effect on an outcome Comparison - the alternative conditional state or alternative exposure state when one is comparing states for the effect on an outcome Outcome - the result or effect of an intervention or exposure in a population PICO (and its variants like PECO or PICOT) is a universal acronym used in evidence-based medicine communities to clearly express research questions and evidence findings. The Evidence resource allows expression of the higher-order concept for recommendations in healthcare where multiple outcomes are considered, and the higher-order concept/combination for framing research questions.

Relationships

The Evidence resource references the EvidenceVariable resource two or more times to clearly specify the relationship among evidence variable concepts in framing a research question, evidence assertion, or recommendation.