ElementDefinition Type: Captures constraints on each element within the resource, profile, or extension.

ElementDefinition
path
Path of the element in the hierarchy of elements
representation
xmlAttr | xmlText | typeAttr | cdaText | xhtml
sliceName
Name for this particular element (in a set of slices)
sliceIsConstraining
If this slice definition constrains an inherited slice definition (or not)
label
Name for element to display with or prompt for element
code
Corresponding codes in terminologies
slicing
This element is sliced - slices follow
discriminator
Element values that are used to distinguish the slices
type
value | exists | type | profile | position
path
Path to element value
description
Text description of how slicing works (or not)
ordered
If elements must be in same order as slices
rules
closed | open | openAtEnd
short
Concise definition for space-constrained presentation
definition
Full formal definition as narrative text
comment
Comments about the use of this element
requirements
Why this resource has been created
alias
Other names
min
Minimum Cardinality
max
Maximum Cardinality (a number or *)
base
Base definition information for tools
path
Path that identifies the base element
min
Min cardinality of the base element
max
Max cardinality of the base element
contentReference
Reference to definition of content for the element
type
Data type and Profile for this element
code
Data type or Resource (reference to definition)
profile
Profiles (StructureDefinition or IG) - one must apply
targetProfile
Profile (StructureDefinition or IG) on the Reference/canonical target - one must apply
aggregation
contained | referenced | bundled - how aggregated
versioning
either | independent | specific
defaultValue[x]
Specified value if missing from instance
meaningWhenMissing
Implicit meaning when this element is missing
orderMeaning
What the order of the elements means
fixed[x]
Value must be exactly this
pattern[x]
Value must have at least these property values
example
Example value (as defined for type)
label
Describes the purpose of this example
value[x]
Value of Example (one of allowed types)
minValue[x]
Minimum Allowed Value (for some types)
maxValue[x]
Maximum Allowed Value (for some types)
maxLength
Max length for string type data
condition
Reference to invariant about presence
constraint
Condition that must evaluate to true
key
Target of 'condition' reference above
requirements
Why this constraint is necessary or appropriate
severity
error | warning
suppress
Suppress warning or hint in profile
human
Human description of constraint
expression
FHIRPath expression of constraint
source
Reference to original source of constraint
mustHaveValue
For primitives, that a value must be present - not replaced by an extension
valueAlternatives
Extensions that are allowed to replace a primitive value
mustSupport
If the element must be supported (discouraged - see obligations)
isModifier
If this modifies the meaning of other elements
isModifierReason
Reason that this element is marked as a modifier
isSummary
Include when _summary = true?
binding
ValueSet details if this is coded
strength
required | extensible | preferred | example
description
Intended use of codes in the bound value set
valueSet
Source of value set
additional
Additional Bindings - more rules about the binding
purpose
maximum | minimum | required | extensible | candidate | current | preferred | ui | starter | component
valueSet
The value set for the additional binding
documentation
Documentation of the purpose of use of the binding
shortDoco
Concise documentation - for summary tables
usage
Qualifies the usage - jurisdiction, gender, workflow status etc.
any
Whether binding can applies to all repeats, or just one
mapping
Map element to another set of definitions
identity
Reference to mapping declaration
map
Details of the mapping
comment
Comments about the mapping or its use