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The definitions, including rules and constraints for valid values for all Data Elements are defined using the following metamodel:
Name: the the name of the data element
Description: a description of the data class
Data type: the constraint on the data element e.g. integer, string
Cardinality: the number of times an lement element can occur within a group
Level: Could, Should, Must
Metadata: any additional metadata associated with the data element
Relationships: related data classes or elements (which may reside in another standard), including child/parent relationships
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