Quantity Types

Namespace: OpenEHR.RM.DataTypes.Quantity

Ordered hierarchy

DvOrdered<T>
├── DvOrdinal            — ranked items (e.g. pain scale 0–10)
└── DvQuantifiable<T>
    ├── DvAmount<T>
    │   ├── DvQuantity   — physical measurement with UCUM units
    │   ├── DvCount      — dimensionless integer count
    │   ├── DvDuration   — ISO 8601 duration (P1Y2M3DT4H…)
    │   └── DvProportion — ratio / fraction / percentage
    └── DvTemporal<T>    — (see Date & Time guide)

DvQuantity

The workhorse type for physical measurements. Units are expressed using UCUM notation.

// Heart rate
var hr = new DvQuantity { Magnitude = 72,   Units = "/min" };

// Temperature (Fahrenheit)
var temp = new DvQuantity { Magnitude = 98.6, Units = "[degF]", Precision = 1 };

// Blood pressure systolic
var bp = new DvQuantity { Magnitude = 120, Units = "mm[Hg]" };

Key properties:

Property	Type	Description
Magnitude	double	The numeric value
Units	string	UCUM unit code
Precision	int?	Decimal places; -1 = unconstrained
MagnitudeStatus	string?	"=" exact, "<" less than, ">" greater than, "~" approx
NormalStatus	CodePhrase?	"N" normal, "H" high, "L" low, …
NormalRange	DvInterval<DvQuantity>?	Reference range

DvCount

A dimensionless integer quantity (e.g. number of episodes, parity).

var parity = new DvCount { Magnitude = 2 };

DvProportion

Represents ratios, percentages, fractions, and unitary values.

// 75 %
var saturation = new DvProportion
{
    Numerator   = 75,
    Denominator = 100,
    Type        = ProportionKind.Percent    // 2 = percent
};

// Ratio 1:4
var ratio = new DvProportion
{
    Numerator   = 1,
    Denominator = 4,
    Type        = ProportionKind.Ratio      // 0 = ratio
};

ProportionKind values: Ratio(0), Unitary(1), Percent(2), Fraction(3), IntegerFraction(4).

DvOrdinal

A ranked item from a discrete ordered set. Stores both a numeric value and a symbol.

var painScore = new DvOrdinal
{
    Value  = 7,
    Symbol = new DvCodedText { Value = "Severe", DefiningCode = … }
};

Ordering — DvOrdinal implements IComparable using the numeric Value.