Shared Health Specification and Guide Version 5.0

For referring to data content defined in other formats.

When providing a summary view (for example with Observation.value[x]) Attachment should be represented with a brief display text such as "Attachment".

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

May be used to represent additional information that is not part of the basic definition of the element. In order 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.

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.

Identifies the type of the data in the attachment and allows a method to be chosen to interpret or render the data. Includes mime type parameters such as charset where appropriate.

Processors of the data need to be able to know how to interpret the data.

Identifies the mime type the binary content is expressed in.

Conformance Rule: The charset will be UTF-8 only.

The human language of the content. The value can be any valid value according to BCP 47.

Users need to be able to choose between the languages in a set of attachments.

The actual data of the attachment - a sequence of bytes. In XML, represented using base64.

The data needs to able to be transmitted inline.

The base64-encoded data SHALL be expressed in the same character set as the base resource XML or JSON.

Location where the attachment is uploaded too or downloaded from, using the unique identifier of the attachment.

The data needs to be transmitted by reference.

Conformance Rule: This will be expressed as a URL on the server - https://EnvironmentSpecificHost/EnvironmentSpecificPathInbox/Binary/[guid or uuid or unique identifier]. The attachment content SHALL be PUT to the same URL immediately after posting the 305 message containing this attachment. It cannot be PUT prior to the 305 message otherwise an error will be returned.

The number of bytes of data that make up this attachment.

Representing the size allows applications to determine whether they should fetch the content automatically in advance, or refuse to fetch it at all.

Conformance Rule: The combined size of all attachments cannot exceed 50 MB.

The calculated hash of the data using SHA-1. Represented using base64.

Included so that applications can verify that the contents of a location have not changed and so that a signature of the content can implicitly sign the content of an image without having to include the data in the instance or reference the url in the signature.

A label or set of text to display in place of the data.

Applications need a label to display to a human user in place of the actual data if the data cannot be rendered or perceived by the viewer.

The date that the attachment was first created.

This is often tracked as an integrity issue for use of the attachment.