Demographics and other administrative information about an individual or animal receiving care or other health-related services.

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 its narrative along with other profiles, value sets, etc.

These resources do not have an independent existence apart from the resource that contains them - they cannot be identified independently, nor can they have their own independent transaction scope. This is allowed to be a Parameters resource if and only if it is referenced by a resource that provides context/meaning.

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.

The registered place of birth of the patient. A sytem may use the address.text if they don't store the birthPlace address in discrete elements.

An Extension

Source of the definition for the extension code - a logical name or a URL.

The definition may point directly to a computable or human-readable definition of the extensibility codes, or it may be a logical URI as declared in some other specification. The definition SHALL be a URI for the Structure Definition defining the extension.

Value of extension - must be one of a constrained set of the data types (see Extensibility for a list).

A parameter that provides guidance on how a recipient should apply settings or reference ranges that are derived from observable information such as an organ inventory, recent hormone lab tests, genetic testing, menstrual status, obstetric history, etc..

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 managable, 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.

An Extension

An Extension

Source of the definition for the extension code - a logical name or a URL.

The definition may point directly to a computable or human-readable definition of the extensibility codes, or it may be a logical URI as declared in some other specification. The definition SHALL be a URI for the Structure Definition defining the extension.

Value of extension - must be one of a constrained set of the data types (see Extensibility for a list).

An Extension

An Extension

Source of the definition for the extension code - a logical name or a URL.

The definition may point directly to a computable or human-readable definition of the extensibility codes, or it may be a logical URI as declared in some other specification. The definition SHALL be a URI for the Structure Definition defining the extension.

Value of extension - must be one of a constrained set of the data types (see Extensibility for a list).

Further explanation about the choice, intention, or context of use for the sex parameter for clinical use

An Extension

Source of the definition for the extension code - a logical name or a URL.

The definition may point directly to a computable or human-readable definition of the extensibility codes, or it may be a logical URI as declared in some other specification. The definition SHALL be a URI for the Structure Definition defining the extension.

Value of extension - must be one of a constrained set of the data types (see Extensibility for a list).

Other clinical evidence or documentation that was used to determine the sex parameter for clincal use

For example, a patient with an initial diagnosis of an intersex condition could have supporting clinical observations specific to the diagnosis. Additional information may be provided in the comment attribute.

An Extension

Source of the definition for the extension code - a logical name or a URL.

The definition may point directly to a computable or human-readable definition of the extensibility codes, or it may be a logical URI as declared in some other specification. The definition SHALL be a URI for the Structure Definition defining the extension.

Value of extension - must be one of a constrained set of the data types (see Extensibility for a list).

The clinical context of uses which the provided SPCU value is intended for.

When present, this attribute clarifies which clinical uses the provided sex parameter value is appropriate or intended for.

An Extension

Source of the definition for the extension code - a logical name or a URL.

The definition may point directly to a computable or human-readable definition of the extensibility codes, or it may be a logical URI as declared in some other specification. The definition SHALL be a URI for the Structure Definition defining the extension.

Value of extension - must be one of a constrained set of the data types (see Extensibility for a list).

Source of the definition for the extension code - a logical name or a URL.

The definition may point directly to a computable or human-readable definition of the extensibility codes, or it may be a logical URI as declared in some other specification. The definition SHALL be a URI for the Structure Definition defining the extension.

Value of extension - must be one of a constrained set of the data types (see Extensibility for a list).

The patient's legal status as citizen of a country.

The nationality of the patient.

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 managable, 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.

Modifier extensions allow for extensions that cannot be safely ignored to be clearly distinguished from the vast majority of extensions which can be safely ignored. This promotes interoperability by eliminating the need for implementers to prohibit the presence of extensions. For further information, see the definition of modifier extensions.

Whether this patient record is in active use. Many systems use this property to mark as non-current patients, such as those that have not been seen for a period of time based on an organization's business rules.

It is often used to filter patient lists to exclude inactive patients

Deceased patients may also be marked as inactive for the same reasons, but may be active for some time after death.

If a record is inactive, and linked to an active record, then future patient/record updates should occur on the other patient.

Need to be able to mark a patient record as not to be used because it was created in error.

Indicates if the individual is deceased or not.

If there's no value in the instance, it means there is no statement on whether or not the individual is deceased. Most systems will interpret the absence of a value as a sign of the person being alive.

The fact that a patient is deceased influences the clinical process. Also, in human communication and relation management it is necessary to know whether the person is alive.

Link to a Patient or RelatedPerson resource that concerns the same actual individual.

There is no assumption that linked patient records have mutual links.

There are multiple use cases:

• Duplicate patient records due to the clerical errors associated with the difficulties of identifying humans consistently, and
• Distribution of patient information across multiple servers.

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 managable, 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.

Modifier extensions allow for extensions that cannot be safely ignored to be clearly distinguished from the vast majority of extensions which can be safely ignored. This promotes interoperability by eliminating the need for implementers to prohibit the presence of extensions. For further information, see the definition of modifier extensions.

Link to a Patient or RelatedPerson resource that concerns the same actual individual.

Referencing a RelatedPerson here removes the need to use a Person record to associate a Patient and RelatedPerson as the same individual.

The type of link between this patient resource and another patient resource.

The type of link between this patient resource and another Patient resource, or Patient/RelatedPerson when using the seealso code

Demographics and other administrative information about an individual or animal receiving care or other health-related services.

The logical id of the resource, as used in the URL for the resource. Once assigned, this value never changes.

Within the context of the FHIR RESTful interactions, the resource has an id except for cases like the create and conditional update. Otherwise, the use of the resouce id depends on the given use case.

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.

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 its narrative along with other profiles, value sets, etc.

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).

IETF language tag for a human language

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 a 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.

These resources do not have an independent existence apart from the resource that contains them - they cannot be identified independently, nor can they have their own independent transaction scope. This is allowed to be a Parameters resource if and only if it is referenced by a resource that provides context/meaning.

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.

An Extension

The registered place of birth of the patient. A sytem may use the address.text if they don't store the birthPlace address in discrete elements.

Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces.

An Extension

Source of the definition for the extension code - a logical name or a URL.

The definition may point directly to a computable or human-readable definition of the extensibility codes, or it may be a logical URI as declared in some other specification. The definition SHALL be a URI for the Structure Definition defining the extension.

Value of extension - must be one of a constrained set of the data types (see Extensibility for a list).

A parameter that provides guidance on how a recipient should apply settings or reference ranges that are derived from observable information such as an organ inventory, recent hormone lab tests, genetic testing, menstrual status, obstetric history, etc..

Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces.

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 managable, 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.

An Extension

Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces.

An Extension

Source of the definition for the extension code - a logical name or a URL.

The definition may point directly to a computable or human-readable definition of the extensibility codes, or it may be a logical URI as declared in some other specification. The definition SHALL be a URI for the Structure Definition defining the extension.

Value of extension - must be one of a constrained set of the data types (see Extensibility for a list).

An Extension

Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces.

An Extension

Source of the definition for the extension code - a logical name or a URL.

The definition may point directly to a computable or human-readable definition of the extensibility codes, or it may be a logical URI as declared in some other specification. The definition SHALL be a URI for the Structure Definition defining the extension.

Value of extension - must be one of a constrained set of the data types (see Extensibility for a list).

Further explanation about the choice, intention, or context of use for the sex parameter for clinical use

Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces.

An Extension

Source of the definition for the extension code - a logical name or a URL.

The definition may point directly to a computable or human-readable definition of the extensibility codes, or it may be a logical URI as declared in some other specification. The definition SHALL be a URI for the Structure Definition defining the extension.

Value of extension - must be one of a constrained set of the data types (see Extensibility for a list).

Other clinical evidence or documentation that was used to determine the sex parameter for clincal use

For example, a patient with an initial diagnosis of an intersex condition could have supporting clinical observations specific to the diagnosis. Additional information may be provided in the comment attribute.

Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces.

An Extension

Source of the definition for the extension code - a logical name or a URL.

The definition may point directly to a computable or human-readable definition of the extensibility codes, or it may be a logical URI as declared in some other specification. The definition SHALL be a URI for the Structure Definition defining the extension.

Value of extension - must be one of a constrained set of the data types (see Extensibility for a list).

The clinical context of uses which the provided SPCU value is intended for.

When present, this attribute clarifies which clinical uses the provided sex parameter value is appropriate or intended for.

Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces.

An Extension

Source of the definition for the extension code - a logical name or a URL.

The definition may point directly to a computable or human-readable definition of the extensibility codes, or it may be a logical URI as declared in some other specification. The definition SHALL be a URI for the Structure Definition defining the extension.

Value of extension - must be one of a constrained set of the data types (see Extensibility for a list).

Source of the definition for the extension code - a logical name or a URL.

The definition may point directly to a computable or human-readable definition of the extensibility codes, or it may be a logical URI as declared in some other specification. The definition SHALL be a URI for the Structure Definition defining the extension.

Value of extension - must be one of a constrained set of the data types (see Extensibility for a list).

The patient's legal status as citizen of a country.

The nationality of the patient.

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 managable, 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.

Modifier extensions allow for extensions that cannot be safely ignored to be clearly distinguished from the vast majority of extensions which can be safely ignored. This promotes interoperability by eliminating the need for implementers to prohibit the presence of extensions. For further information, see the definition of modifier extensions.

An identifier for this patient.

Patients are almost always assigned specific numerical identifiers.

Whether this patient record is in active use. Many systems use this property to mark as non-current patients, such as those that have not been seen for a period of time based on an organization's business rules.

It is often used to filter patient lists to exclude inactive patients

Deceased patients may also be marked as inactive for the same reasons, but may be active for some time after death.

If a record is inactive, and linked to an active record, then future patient/record updates should occur on the other patient.

Need to be able to mark a patient record as not to be used because it was created in error.

A name associated with the individual.

A patient may have multiple names with different uses or applicable periods. For animals, the name is a "HumanName" in the sense that is assigned and used by humans and has the same patterns. Animal names may be communicated as given names, and optionally may include a family name.

Need to be able to track the patient by multiple names. Examples are your official name and a partner name. The Alphabetic representation of the name SHALL be always provided

Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces.

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 managable, 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.

Reason for not providing the name.

Identifies the purpose for this name.

Applications can assume that a name is current unless it explicitly says that it is temporary or old.

The use of a human name.

Allows the appropriate name for a particular context of use to be selected from among a set of names.

Text representation of the full name. Due to the cultural variance around the world a consuming system may not know how to present the name correctly; moreover not all the parts of the name go in given or family. Creators are therefore strongly encouraged to provide through this element a presented version of the name. Future versions of this guide may require this element.

Can provide both a text representation and parts. Applications updating a name SHALL ensure that when both text and parts are present, no content is included in the text that isn't found in a part.

A renderable, unencoded form.

Family name. When more the family is composed by more than one names, this element documents the full composed family name with the proper * name.familyrder. The parts are recorded in the fhater and mother family names extensions.

Family Name may be decomposed into specific parts using extensions (de, nl, es related cultures).

Given name.

If only initials are recorded, they may be used in place of the full name parts. Initials may be separated into multiple given names but often aren't due to paractical limitations. This element is not called "first name" since given names do not always come first.

Part of the name that is acquired as a title due to academic, legal, employment or nobility status, etc. and that appears at the start of the name.

Part of the name that is acquired as a title due to academic, legal, employment or nobility status, etc. and that appears at the end of the name.

Indicates the period of time when this name was valid for the named person.

Allows names to be placed in historical context.

A contact detail (e.g. a telephone number or an email address) by which the individual may be contacted.

A Patient may have multiple ways to be contacted with different uses or applicable periods. May need to have options for contacting the person urgently and also to help with identification. The address might not go directly to the individual, but may reach another party that is able to proxy for the patient (i.e. home phone, or pet owner's phone).

People have (primary) ways to contact them in some way such as phone, email.

Administrative Gender - the gender that the patient is considered to have for administration and record keeping purposes.

The gender might not match the biological sex as determined by genetics or the individual's preferred identification. Note that for both humans and particularly animals, there are other legitimate possibilities than male and female, though the vast majority of systems and contexts only support male and female. Systems providing decision support or enforcing business rules should ideally do this on the basis of Observations dealing with the specific sex or gender aspect of interest (anatomical, chromosomal, social, etc.) However, because these observations are infrequently recorded, defaulting to the administrative gender is common practice. Where such defaulting occurs, rule enforcement should allow for the variation between administrative and biological, chromosomal and other gender aspects. For example, an alert about a hysterectomy on a male should be handled as a warning or overridable error, not a "hard" error. See the Patient Gender and Sex section for additional information about communicating patient gender and sex.

The gender of a person used for administrative purposes.

Needed for identification of the individual, in combination with (at least) name and birth date.

The date of birth for the individual.

Partial dates are allowed if the specific date of birth is unknown. There is a standard extension "patient-birthTime" available that should be used where Time is required (such as in maternity/infant care systems).

Age of the individual drives many clinical processes.

unique id for the element within a resource (for internal references)

An Extension

The time of day that the Patient/Person/RelatedPerson/Practitioner was born. This includes the date to ensure that the timezone information can be communicated effectively.

The patient prefix on the extension was retained to ensure backward compatibility with existing data (the content itself is provided to assist in sharing data across patient resources effectively)

The actual value

Indicates if the individual is deceased or not.

If there's no value in the instance, it means there is no statement on whether or not the individual is deceased. Most systems will interpret the absence of a value as a sign of the person being alive.

The fact that a patient is deceased influences the clinical process. Also, in human communication and relation management it is necessary to know whether the person is alive.

An address for the individual.

Patient may have multiple addresses with different uses or applicable periods.

May need to keep track of patient addresses for contacting, billing or reporting requirements and also to help with identification.

This field contains a patient's most recent marital (civil) status.

The domestic partnership status of a person.

Most, if not all systems capture it.

Indicates whether the patient is part of a multiple (boolean) or indicates the actual birth order (integer).

Where the valueInteger is provided, the number is the birth number in the sequence. E.g. The middle birth in triplets would be valueInteger=2 and the third born would have valueInteger=3 If a boolean value was provided for this triplets example, then all 3 patient records would have valueBoolean=true (the ordering is not indicated).

For disambiguation of multiple-birth children, especially relevant where the care provider doesn't meet the patient, such as labs.

Image of the patient.

Guidelines:

• Use id photos, not clinical photos.
• Limit dimensions to thumbnail.
• Keep byte count low to ease resource updates.

Many EHR systems have the capability to capture an image of the patient. Fits with newer social media usage too.

A contact party (e.g. guardian, partner, friend) for the patient.

Contact covers all kinds of contact parties: family members, business contacts, guardians, caregivers. Not applicable to register pedigree and family ties beyond use of having contact.

Need to track people you can contact about the patient.

Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces.

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 managable, 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.

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 managable, 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.

Modifier extensions allow for extensions that cannot be safely ignored to be clearly distinguished from the vast majority of extensions which can be safely ignored. This promotes interoperability by eliminating the need for implementers to prohibit the presence of extensions. For further information, see the definition of modifier extensions.

The nature of the relationship between the patient and the contact person.

The nature of the relationship between a patient and a contact person for that patient.

Used to determine which contact person is the most relevant to approach, depending on circumstances.

A name associated with the contact person.

Contact persons need to be identified by name, but it is uncommon to need details about multiple other names for that contact person.

A contact detail for the person, e.g. a telephone number or an email address.

Contact may have multiple ways to be contacted with different uses or applicable periods. May need to have options for contacting the person urgently, and also to help with identification.

People have (primary) ways to contact them in some way such as phone, email.

Address for the contact person.

Need to keep track where the contact person can be contacted per postal mail or visited.

Administrative Gender - the gender that the contact person is considered to have for administration and record keeping purposes.

The gender of a person used for administrative purposes.

Needed to address the person correctly.

Organization on behalf of which the contact is acting or for which the contact is working.

For guardians or business related contacts, the organization is relevant.

The period during which this contact person or organization is valid to be contacted relating to this patient.

A language which may be used to communicate with the patient about his or her health.

If no language is specified, this implies that the default local language is spoken. If you need to convey proficiency for multiple modes, then you need multiple Patient.Communication associations. For animals, language is not a relevant field, and should be absent from the instance. If the Patient does not speak the default local language, then the Interpreter Required Standard can be used to explicitly declare that an interpreter is required.

If a patient does not speak the local language, interpreters may be required, so languages spoken and proficiency are important things to keep track of both for patient and other persons of interest.

Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces.

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 managable, 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.

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 managable, 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.

Modifier extensions allow for extensions that cannot be safely ignored to be clearly distinguished from the vast majority of extensions which can be safely ignored. This promotes interoperability by eliminating the need for implementers to prohibit the presence of extensions. For further information, see the definition of modifier extensions.

The ISO-639-1 alpha 2 code in lower case for the language, optionally followed by a hyphen and the ISO-3166-1 alpha 2 code for the region in upper case; e.g. "en" for English, or "en-US" for American English versus "en-AU" for Australian English.