A reference to a document of any kind for any purpose. Provides metadata about the document so that the document can be discovered and managed. The scope of a document is any seralized object with a mime-type, so includes formal patient centric documents (CDA), cliical notes, scanned paper, and non-patient specific documents like policy text.

DocumentReference
masterIdentifier
Master Version Specific Identifier
identifier
Other identifiers for the document
status
current | superseded | entered-in-error
docStatus
preliminary | final | amended | entered-in-error
type
Kind of document (LOINC if possible)
category
Categorization of document
subject
Who/what is the subject of the document
date
When this document reference was created
author
Who and/or what authored the document
authenticator
Who/what authenticated the document
custodian
Organization which maintains the document
relatesTo
Relationships to other documents
code
replaces | transforms | signs | appends
target
Target of the relationship
description
Human-readable description
securityLabel
Document security-tags
content
Document referenced
attachment
Where to access the document
format
Format/content rules for the document
context
Clinical context of document
encounter
Context of the document content
event
Main clinical acts documented
period
Time of service that is being documented
facilityType
Kind of facility where patient was seen
practiceSetting
Additional details about where the content was created (e.g. clinical specialty)
sourcePatientInfo
Patient demographics from source