Basic Data Types

Namespace: OpenEHR.RM.DataTypes.Basic

The Basic package contains the root abstract class and three concrete leaf types that represent fundamental non-specialist values.

DataValue (abstract)

All openEHR data-type classes inherit from DataValue. It carries no mandatory properties of its own but establishes the type hierarchy that allows any leaf value to be stored in an Element.Value.

DvBoolean

A simple true/false value. Maps to DV_BOOLEAN in the spec.

var flag = new DvBoolean { Value = true };

Invariant — Value must be set; the type has no meaningful null state.

DvState

Represents a state machine state. Contains a DvCodedText (the state name) and an optional boolean indicating whether the state is a terminal state.

var state = new DvState
{
    Value      = new DvCodedText { Value = "active", DefiningCode = … },
    IsTerminal = false
};

Note — DvState is rarely used in modern openEHR clinical archetypes; prefer DvCodedText for status values.

DvIdentifier

An identifier from an external system (e.g. a hospital MRN, an NHS number).

var mrn = new DvIdentifier
{
    Issuer   = "NHS Digital",
    Assigner = "NHS Digital",
    Id       = "943-476-0165",
    Type     = "NHS number"
};

Property	Mandatory	Description
Issuer	✅	Name of the organisation that issued the ID
Assigner	✅	Name of the organisation that assigned it
Id	✅	The identifier string
Type	❌	Optional classification (e.g. "MRN", "NHSNumber")