Rationale for Correction:Some occurrences of units for ratio in Templates and Context Groups are incorrect.[Ed.Note: Only selected examples of correct usage are provided for reference.]
Correction Wording:
Amend PS3.16 as follows (changes to existing text are bold and underlined for additions and struckthrough for removals):
Abstract Multi-dimensional Image Model Component Semantics
Abstract Multi-dimensional Image Model Component Semantics
Coding Scheme Designator
Code Value
Code Meaning
SNOMED-RT ID
UMLS Concept Unique ID
Units
DCM
113098
Magnetization Transfer Ratio
DT ({ratio}, UCUM, "ratio")
DCM
126396
Magnetic Susceptibility
DT ({ratio}, UCUM, "ratio")
DCM
130086
Relative Linear Stopping Power
DT ({ratio}, UCUM, "ratio")
RT Segment Characteristics
RT Segment Characteristics
NL
VT
Concept Name
VM
Req Type
Condition
Value Set Constraint
1
NUMERIC
EV (130082, DCM, "Relative Mass Density")
1
U
Units = EV ({ratio}, UCUM, "ratio")
2
NUMERIC
EV (130083, DCM, "Relative Electron Density")
1
U
Units = EV ({ratio}, UCUM, "ratio")
3
NUMERIC
EV (130084, DCM, "Effective Z")
1
U
Units = EV (1, UCUM, "no units")
5
NUMERIC
EV (130086, DCM, "Relative Linear Stopping Power")
1
U
Units = EV ({ratio}, UCUM, "ratio")
7
NUMERIC
EV (130088, DCM, "Linear Cell Kill Factor")
1
U
Units = EV ({ratio}, UCUM, "ratio")
8
NUMERIC
EV (130089, DCM, "Quadratic Cell Kill Factor")
1
U
Units = EV ({ratio}, UCUM, "ratio")
9
NUMERIC
EV (130090, DCM, "High Dose Fraction Linear Cell Kill Factor")
1
U
Units = EV ({ratio}, UCUM, "ratio")
12
NUMERIC
EV (130093, DCM, "Atomic Number")
1-n
U
Units = EV (1, UCUM, "no units")
13
>
NUMERIC
EV (130094, DCM, "Elemental Composition Atomic Mass Fraction")
1
M
Units = EV ({ratio}, UCUM, "ratio")
14
NUMERIC
EV (130095, DCM, "alpha gEUD value")
1
U
Units = EV ({ratio}, UCUM, "ratio")
Rows 12, 13
The value of (130094, DCM, "Elemental Composition Atomic Mass Fraction") annotates the fractional weight of the elements identified by the (130093, DCM, "Atomic Number") with respect to the total mass of the segment. The allowed value is in the range of [0, 1].
For reference unchanged in PS3.16 :
Context Group Table Field Definition...An optional column may provide a normative baseline or defined set of units to use for numeric measurements using the concept,
either as a single term (e.g., DT ({ratio}, UCUM, "ratio")), a list of such terms,
or a reference to a Context Group (e.g., DCID 7277 "Units of Diffusion Rate Area Over Time")....Units of Measurement...The specialization of the UCUM standard as it is used in DICOM involves the following rules:...In the case of UCUM unity ("1", or curly braces expression) it is forbidden to use "1" as a Code Meaning. provides Code Meanings for a Code Value (0008,0100) of 1. A Template or Context Group may constrain the Code Meaning according to the following rules:UCUM default unit 1 shall use one of the Code Meaning synonyms specified in ratios of identically dimensioned values may use ({ratio}, UCUM, "ratio")unitless numeric scores may use ({M:N}, UCUM, "range: M:N") to specify the minimum and maximum value, for example, ({0:10}, UCUM, "range: 0:10")counts using UCUM annotation shall always use the text within the curly braces as the Code Meaning, for example, ({masses}, UCUM, "masses")compositions of a curly braces expression with other UCUM values may use a conventional clinical representation, for example, ({H.B.}/min, UCUM, "BPM")...VA Main Results
VA Main Results
NL
Rel with Parent
VT
Concept Name
VM
Req Type
Condition
Value Set Constraint
4
>
CONTAINS
NUM
EV (122435, DCM, "Regression Volume Exponent")
1
U
Unit = DT (1, UCUM, "no units")
5
>
CONTAINS
NUM
EV (122431, DCM, "Regression Slope ED")
1
U
Unit = DT ({ratio}, UCUM, "ratio")
7
>
CONTAINS
NUM
EV (122433, DCM, "Regression Slope ES")
1
U
Unit = DT ({ratio}, UCUM, "ratio")
Tracer Kinetic Model Parameters
Tracer Kinetic Model Parameters
Coding Scheme Designator
Code Value
Code Meaning
Units
DCM
126314
ve
DT ({ratio}, UCUM, "ratio")
DCM
126331
vp
DT ({ratio}, UCUM, "ratio")
Abstract Multi-dimensional Image Model Component Units
Abstract Multi-dimensional Image Model Component Units
Coding Scheme Designator
Code Value
Code Meaning
UCUM
1
no units
UCUM
{ratio}
ratio
...
English Code Meanings of Selected Codes (Normative)